Application of Immunohistochemistry to Gynecologic Pathology

Application of Immunohistochemistry to Gynecologic Pathology Khush Mittal, MD; Robert Soslow, MD; W. G. McCluggage, FRCPath

● Context.—A large variety of tumors and lesions arise in the female genital tract. Although the majority of these can be correctly recognized on routine hematoxylin-eosin– stained slides, occasional cases present a diagnostic challenge. Immunohistochemical stains are extremely useful in resolving many of these problematic cases. As the knowledge in this area is constantly expanding, it is useful to have this updated information in a review form for easy access. Objective.—To present our current knowledge of im-

munohistochemistry of the lesions of the female genital tract in a readily accessible form. Data Sources.—The review is based on previously published articles on this topic. Conclusions.—Immunohistochemical stains help in reaching a conclusive diagnosis in a variety of problematic lesions seen in gynecologic pathology. As in any other system, immunohistochemical findings need to be interpreted in light of the clinical history and morphologic findings. (Arch Pathol Lab Med. 2008;132:402–423)

I

monly metastasize to the ovary include those from the endometrium, colon, and breast. Diffuse expression of cytokeratin (CK) 7 is seen in primary ovarian carcinoma, but such expression is not seen in colon carcinoma.4 WT1 and CA 125 are associated with ovarian carcinoma, but their expression varies with different histologic subtypes. WT15,6 and CA 1254,7–9 are expressed in most primary ovarian serous adenocarcinomas but are negative in a majority of ovarian clear cell and mucinous carcinomas.6 Endometrioid ovarian carcinoma is positive for CA 125 but usually negative for WT1.6 WT1 is usually negative in breast, gastrointestinal, and pancreatobiliary primaries. CA 125 is expressed in a minority of carcinomas other than those from ovary, including carcinomas from breast, endometrium, cervix, and lung. Approximately 40% of primary ovarian carcinomas are estrogen receptor (ER) and/or progesterone receptor (PR) positive.4,10 Carcinomas arising in breast and other sites in the female genital tract are also ER and PR positive, whereas carcinomas from other locations are ER and PR negative. CDX2 and ␤-catenin are useful markers for colon carcinoma, and gross cystic disease fluid protein 15 (GCDFP-15) is a useful marker for breast carcinoma. Immunohistochemical markers useful in differentiating primary ovarian carcinoma from metastatic carcinoma from a particular site are further discussed later. Suggested panel: CK7, CK20, WT1, ER, PR, GCDFP-15, CDX2, DPC4, p16, ␤-catenin.

mmunohistochemical findings play a crucial role in the differential diagnosis of gynecologic lesions.1–3 Because of the limitations of space, this article is almost exclusively focused on the application of immunohistochemical findings in gynecologic pathology. Nevertheless, the significance of clinical and morphologic findings in arriving at a diagnosis or differential diagnosis in any branch of surgical pathology, including gynecologic pathology, cannot be overstated. Tumors often show aberrant expression of proteins, and none of the markers discussed in this study, with the possible exception of thyroglobulin, are specific for a particular tumor type. Therefore, the use of a panel of antibodies is generally recommended. The article is organized by organ sites and further subcategorized by the differential diagnoses encountered in these locations. A panel of antibodies is suggested for each differential diagnosis based on our experience and published literature. These panels may be modified based on personal experience of the user and local availability of the antibodies. OVARY Primary Ovarian Adenocarcinoma Versus Adenocarcinomas Metastatic to the Ovary This is the most common reason for immunohistochemical studies of ovarian lesions. Carcinomas that most comAccepted for publication April 16, 2007. From the Department of Pathology, NYU School of Medicine and Surgical and Ob-Gyn Pathology, Bellevue Hospital, New York (Dr Mittal); the Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY (Dr Soslow); and the Department of Pathology, Royal Group of Hospitals Trust, Belfast, United Kingdom (Dr McCluggage). The authors have no relevant financial interest in the products or companies described in this article. Reprints: Khush Mittal, MD, Bellevue Hospital, Room 4 west 1, 462 First Ave, New York, NY 10016 (e-mail: [email protected]). 402 Arch Pathol Lab Med—Vol 132, March 2008

Primary Endometrioid Carcinoma Versus Metastatic Colon Carcinoma Because the expression of mucin may be low in colonic carcinoma, it is most often confused with an endometrioid carcinoma when metastatic to the ovary. Endometrioid carcinoma is positive for CK7, ER, PR, and CA 125 and negative for CK20.4,9–12 Colon carcinoma shows a reverse pattern (Figure 1, A and B). Other adenocarcinomas, inImmunohistochemistry in Gynecologic Pathology—Mittal et al

Figure 1. Colon adenocarcinoma, metastatic to the ovary, showing positive staining for cytokeratin (CK) 20 (A) and negative staining for CK7 (B) (original magnifications ⫻100). Figure 2. Decidualized endometriosis in ovary. A, The arrow points to atrophic glandular epithelium that may be mistaken for endothelial lining (hematoxylin-eosin, original magnification ⫻100). B, Cytokeratin AE1/AE3 highlights the glandular structures (original magnification ⫻100). Figure 3. Dysgerminoma and lymphoma may be distinguished from each other by staining for placental alkaline phosphatase (PLAP) and CD45. A, Dysgerminoma positive for PLAP (origianl magnification ⫻100). B, Lymphoma positive for CD45 (original magnification ⫻100).

Arch Pathol Lab Med—Vol 132, March 2008

Immunohistochemistry in Gynecologic Pathology—Mittal et al 403

cluding endometrial, endocervical, breast, and lung, are also positive for CK7 and negative for CK20; hence, these primary sites cannot be excluded based on this immunophenotype alone. Suggested panel: CK7, CK20, ER, PR, CA 125.

of primary ovarian carcinomas, except for serous ovarian carcinomas,38 which frequently show the same immunophenotype as cervical adenocarcinoma. However, primary papillary serous carcinomas are rare in the cervix. Suggested panel: ER, PR, p16.

Primary Mucinous Carcinoma Versus Metastatic Colon Carcinoma Primary mucinous carcinomas are frequently positive for CK204,9–14; hence, CK20 cannot be used to distinguish these tumors from metastatic colon carcinoma. Cytokeratin 7 is more useful in this situation, as it is diffusely positive in ovarian carcinoma and negative or focally positive in colon carcinoma. Ovarian mucinous carcinoma is negative for ␤-catenin and positive for MUC5AC, whereas colon carcinoma shows a reverse pattern.4,9–15 CDX2 is a sensitive but nonspecific marker for colon carcinoma.13,16,17 A negative staining would favor ovarian primary. Mucinous tumors with intestinal type histology and immunostaining pattern may arise from ovarian teratomas.18 Suggested panel: CK7, CA 125, ER, PR, CDX2, MUC5AC.

Ovarian Adenocarcinoma Versus Epithelioid Mesothelioma

Primary Clear Cell Carcinoma Versus Metastatic Renal Clear Cell Carcinoma Renal cell carcinoma is negative for CK7 in contrast to ovarian clear cell carcinoma.13,16,17,19,20 Renal cell carcinoma is positive for CD10,19,21 whereas ovarian clear cell carcinoma is negative. Suggested panel: CK7, CA 125, CD10, ER, PR. Primary Adenocarcinoma Versus Metastatic Gastric Carcinoma Occasional primary ovarian mucinous carcinomas may have signet ring cells. Usually this is a minor component of the tumor. Cytokeratin 7 and CK20 are not very helpful in this differential diagnosis as both these tumor types can be CK7 and CK20 positive.11,22,23 Nevertheless, positive staining for CK7, ER, and PR and lack of diffuse positive staining for CK20 would favor an ovarian origin. Suggested panel: CK7, CK20, CA 125, ER, PR. Ovarian Adenocarcinoma Versus Metastatic Breast Carcinoma Breast carcinoma is usually positive for GCDFP-15 and negative for vimentin.4 Ovarian carcinomas are negative for GCDFP-15 and often positive for vimentin. If ER and PR data are available on a prior breast carcinoma, these data may be compared with the findings in the current tumor in the ovary. Suggested panel: GCDFP-15, vimentin, ER, PR.

Calretinin, thrombomodulin, and keratin 5/6 are the best positive markers for mesotheliomas.39–46 The best negative markers for mesothelioma are MOC-31, B72.3, BerEP4, CA 19-9, and Leu-M1.7,39,40,42,46–53 Suggested panel: calretinin, keratin 5/6, B72.3, CA 19.9, Leu-M1. Reactive Mesothelium Versus Implants or Serous Carcinoma Ber-EP4 and epithelial membrane antigen (EMA) are positive in implants and carcinoma but negative in reactive mesothelium. Calretinin shows a reverse pattern, with positive nuclear staining in mesothelium and usually lack of such staining in carcinomas. Suggested panel: calretinin, Ber-EP4, EMA. Ovarian Adenocarcinoma Versus Sex Cord Stromal Tumor Ber-EP4 and EMA are positive in carcinoma and negative in sex cord stromal tumors, with the exception of juvenile granulosa cell tumors, which may show positivity for EMA in up to 50% of the tumors.54 Epithelial membrane antigen is also negative in female adnexal tumors of wolffian origin. In contrast, sex cord stromal tumors are positive for inhibin55,56 and calretinin,57,58 whereas ovarian carcinomas are usually negative. Cytokeratin AE1/AE3 staining is present in all carcinomas and in Sertoli cell tumors59 and may be present in granulosa cell tumors, often in a dotlike paranuclear pattern. A negative staining for AE1/AE3 supports a diagnosis of sex cord stromal tumor. Suggested panel: inhibin, Ber-EP4, EMA, AE1/AE3. Ovarian Adenocarcinoma Versus Adenocarcinoid Chromogranin, CD56, and synaptophysin are useful markers for carcinoids. Chromogranin is highly specific. CD56 and synaptophysin are less specific but more sensitive.12 The possibility of a metastasis from an appendiceal primary must be considered when diagnosing a case of ovarian adenocarcinoid. Suggested panel: chromogranin, CD56. Ovarian Endometrioid Adenocarcinoma Versus Sertoli Cell Tumor

Ovarian Adenocarcinoma Versus Metastatic Pancreatic and Bile Duct Carcinoma Pancreatic carcinomas often show loss of DPC4.24–27 Ovarian adenocarcinomas are usually negative for CA 199, which is expressed in both pancreatic and bile duct carcinomas. Suggested panel: CA 19-9, DPC4, ER, PR.

Endometrioid adenocarcinoma and Sertoli cell tumors can look similar on morphology. Ovarian adenocarcinoma is positive for EMA and CK7, whereas Sertoli cell tumors are positive for ␣-inhibin and vice versa.60–63 Suggested panel: EMA, CK7, ␣-inhibin.

Ovarian Adenocarcinoma Versus Metastatic Cervical Adenocarcinoma Cervical adenocarcinoma is usually negative for ER and PR28–31 and positive for p16,32–37 whereas the reverse is true

Embryonal carcinomas are positive for human chorionic gonadotropin (hCG) and ␣-fetoprotein. OCT4 is positive in nuclei in embryonal carcinoma and dysgerminoma but is negative in most adenocarcinomas.63–66

404 Arch Pathol Lab Med—Vol 132, March 2008

Ovarian Adenocarcinomas Versus Embryonal Carcinoma

Immunohistochemistry in Gynecologic Pathology—Mittal et al

Origins of a Diffuse Peritoneal Adenocarcinoma in a Female Expression of WT1 and to a lesser extent CA 125 favors an ovarian or mu¨llerian primary peritoneal carcinoma. Most gastrointestinal, lung, and breast primaries are negative for WT1. Lung and thyroid adenocarcinomas are thyroid transcription factor 1 (TTF-1) positive as are neuroendocrine carcinomas in other locations.67–70 Malignant mesothelioma is also WT1 positive. Suggested panel: CK7, CK20, WT1, CA 125, ER, PR, TTF-1, calretinin, DPC4, GCDFP-15, ␤-catenin. Distinction of Endometriosis From Cystic Struma Ovarii Struma ovarii can be cystic and resemble an endometriotic cyst. Thyroglobulin is very useful in supporting a diagnosis of struma ovarii.71 Ovarian Adenocarcinomas Versus Endodermal Sinus Tumor ␣-Fetoprotein is positive in endodermal sinus tumor. Ovarian Clear Cell Carcinoma Versus Dysgerminoma or Endodermal Sinus Tumor Clear cell carcinoma is positive for AE1/AE3 and negative for placental alkaline phosphatase (PLAP). Dysgerminoma shows a reverse pattern, except that rarely focal AE1/AE3 staining may be seen.72 Endodermal sinus tumor is positive for ␣-fetoprotein and AE1/AE3. Ovarian Lesions With Abundant Cytoplasm and Small Uniform Nuclei These lesions include Leydig cell tumor, corpus luteum, decidual change, and decidualized endometriosis (Figure 2, A). A cytokeratin stain is helpful in identifying glandular components in decidualized endometriosis, as the glandular epithelium may be flattened and confused with endothelial lining (Figure 2, B). An immunostain for testosterone may confirm the diagnosis of Leydig cell tumor. Ovarian Tumors With Small Blue Cells A variety of tumors in the ovary may have a pattern of small blue cells.73 These include granulosa cell tumor (positive for inhibin), primary small cell carcinoma (variably positive for AE1/AE3, EMA, CD10, calretinin, WT1, and p53), metastatic small cell carcinoma (positive for TTF-1), dysgerminoma (positive for PLAP [Figure 3, A] and OCT474), lymphoma (positive for CD45; Figure 3, B), and immature teratoma (positive for neurofilament protein,75 synaptophysin, neuron-specific enolase). Recommended panel: AE1/3, EMA, CD10, calretinin, WT1, TTF-1, CD45, inhibin, synaptophysin, neurofibrillary protein, PLAP. Distinction Between Lymphangioma and Benign Cystic Mesothelioma These lesions have similar morphology, but mesothelioma reacts with cytokeratin AE1/AE3,76 whereas lymphangioma would be positive for D2-40.77 FALLOPIAN TUBE Adenocarcinoma In Situ Versus Normal Atypia Normal tubal epithelium often appears atypical (Figure 4, A). This atypical epithelium may lead to a misdiagnosis of adenocarcinoma in situ (AIS) or the missed diagnosis Arch Pathol Lab Med—Vol 132, March 2008

of AIS in the fallopian tube. MIB-1 and p53 are very useful in this differential diagnosis, as these are negative in normal epithelium (Figure 4, B) and show increased expression in the in situ carcinoma of the fallopian tube78 (Figure 4, C and D). UTERINE CORPUS Endocervical Adenocarcinoma Versus Uterine Endometrioid Carcinoma Distinguishing between an endocervical adenocarcinoma of the usual type (ECA) and a uterine endometrioid carcinoma (UEC) can often be accomplished by routine histologic examination, but a significant degree of morphologic overlap between the entities prompts many pathologists to use immunohistochemistry for this differential diagnosis. Carcinoembryonic antigen (CEA) expression is more common in ECAs (up to 100%) than in UECs (up to 50% in some series), but this lack of discrimination should discourage its use as a single marker on an individual case basis.79–81 Carcinoembryonic antigen expression in UECs, which is usually weak and luminal, contrasts with that in ECAs, in which expression is cytoplasmic, luminal, and of strong intensity. Vimentin staining is a useful diagnostic adjunct because coexpression of vimentin and cytokeratin is seen in most UECs but not ECAs.82 The use of ER, PR, and p16 for the distinction of endocervical and endometrial adenocarcinoma has recently become popular.83–85 Using these markers as part of a panel makes use of frequent ER and PR expression in differentiated UECs and the association between high-risk human papillomavirus (HPV) infection, implicated in ECAs, and overexpression of p16. In summary, most International Federation of Gynecology and Obstetrics (FIGO) grades 1 and 2 UECs would express ER, PR, and vimentin, whereas most ECAs are ER and PR negative but express CEA and p16 diffusely (Table 1). Many UECs are negative with p16 immunostaining or show patchy positivity. Making generalizations about the typical staining pattern of endocervical and endometrial carcinomas can be misleading. For example, there are reports suggesting that mesonephric, clear cell, and minimal-deviation endocervical adenocarcinomas may not be HPV-related,86 which calls into question the validity of the idea that ‘‘endocervical adenocarcinomas are p16 positive.’’ Data that are even better established suggest that endometrial adenocarcinomas, including types much more frequently encountered than these unusual cervical tumors, are heterogeneous and do not conform to the profiles discussed in the preceding paragraph.87 Specifically, serous carcinomas are consistently strongly and diffusely positive for p16, whereas FIGO grade 3 and clear cell carcinomas may show considerable staining as well.87 Serous carcinomas are well known to lack ER and PR expression; most clear cell carcinomas, in fact, are entirely negative for these markers. Therefore, the CEA, vimentin, ER, PR, and p16 panel should be used with a great deal of caution when the tumor in question could be of mesonephric, minimal deviation, serous, clear cell, FIGO grade 3 endometrioid or undifferentiated type. We strongly advocate close clinical correlation when there is uncertainty about a tumor’s origin. Clinical and radiologic findings should outweigh immunohistochemiImmunohistochemistry in Gynecologic Pathology—Mittal et al 405

Figure 4. Fallopian tube epithelium can appear atypical (A; hematoxylin-eosin, original magnification ⫻100), but negative immunostains for p53 (B; original magnification ⫻100) and MIB-1 would exclude that diagnosis. In other cases, morphologic suspicion of intraepithelial serous carcinoma (C; MIB-1, original magnification ⫻100) would be confirmed by positive staining for p53 (D; original magnification ⫻100). The arrow in C points to the normal epithelium.

Table 1. Endocervical Adenocarcinoma* Versus Endometrioid Adenocarcinoma (FIGO Grades 1 and 2)† CEA

Vimentin

ER/PR

p16

Endocervical ⫹ N N ⫹ Endometrioid N ⫹ ⫹ ⫺/⫹ * Human papillomavirus associated. † CEA indicates carcinoembryonic antigen; ER/PR, estrogen receptor/ progesterone receptor; ⫹, positive; N, negative; and ⫺/⫹, mostly negative. CEA staining is cytoplasmic.

cal data in this context, although the approach to each case should be individualized. Suggested panel: vimentin, ER, PR, monoclonal CEA, p16. Microglandular Hyperplasia Versus Mucinous Endometrial Adenocarcinoma These can appear strikingly similar.88,89 Older age, luminal squamous metaplasia, at least moderate cytologic atypia, easily found mitotic activity, and stromal foam cells favor mucinous endometrial adenocarcinoma, whereas younger age, recent history of hormone use, and sub406 Arch Pathol Lab Med—Vol 132, March 2008

nuclear vacuoles favor microglandular hyperplasia. Unlike endocervical adenocarcinoma, microglandular hyperplasia is usually CEA negative and shows variable expression of ER and PR, which means that these markers are not useful when mucinous endometrial adenocarcinoma is under consideration. A more useful immunohistochemical panel would include vimentin and MIB-1.88 Microglandular hyperplasia lacks anti-vimentin immunoreactivity and usually shows only occasional nuclei (less than 1%) positive with MIB-1. In contrast, most endometrioid adenocarcinomas and mucinous endometrial adenocarcinomas express vimentin and demonstrate a proliferation index of at least approximately 10%. Suggested panel: vimentin, MIB-1. Arias-Stella Reaction Versus Clear Cell Carcinoma The Arias-Stella reaction is a well known mimic of clear cell carcinoma. A recent study90 reported only 3 of 27 Arias-Stella cases showing greater than 5% nuclear labeling with MIB-1; this contrasted with clear cell carcinomas, in which 9 of 11 cases showed at least 5% labeling. Therefore, although clear cell carcinomas are generally much more proliferative than Arias-Stella reactions, there is some overlap. p53 immunohistochemical results were similar. Immunohistochemistry in Gynecologic Pathology—Mittal et al

Most Arias-Stella reactions were negative, and only occasional cases showed p53 expression greater than 25%. Clear cell carcinomas tended to demonstrate larger percentages of p53-positive nuclei, but only 7 of 11 contained greater than 25% positive nuclei. Suggested panel: MIB-1, p53. Invasive Endometrial Cancer Versus Noninvasive Endometrial Cancer Involving Adenomyosis CD10 expression is characteristic of endometrial stroma, whereas it is significantly less frequently observed in myometrial smooth muscle. Several authors have used this observation to study whether CD10 is useful for distinguishing invasive endometrial cancer from adenocarcinomas involving adenomyosis.91,92 They hypothesized that CD10 expression surrounding adenocarcinoma in the myometrium would support a diagnosis of adenomyosis over invasive carcinoma.91,92 Instead, their articles report that a rim of CD10-positive tissue frequently envelops many myoinvasive adenocarcinomas, leading to the mistaken impression of a carcinoma that colonizes adenomyosis.91,92 There are also occasional problems involving endometrial stroma that fails to express CD10. In these cases, the endometrial stroma surrounding an endometrial cancer involving adenomyosis demonstrates smooth muscle or fibroblastic phenotype, reminiscent of the stroma of some endometrial polyps. Stroma demonstrating fibroblastic differentiation frequently only expresses CD10 weakly or focally. Therefore, lacking or weak CD10 expression does not entirely exclude the presence of endometrial stroma and adenomyosis. Suggested panel: none. Uterine Serous Carcinoma Versus UEC Immunohistochemistry, useful diagnostically, has also been used to highlight these tumors’ divergent pathogenetic pathways. Strong p53 immunoreactivity (overexpression) is seen in more than 80% of uterine serous carcinomas (USCs) (Figure 5, A through F; Figure 6, A); in contrast, p53 is overexpressed in less than 20% of UECs93,94 (Figure 5, G; Table 2). p53 expression in UECs is negative or weak in grade 1 to grade 2 tumors, whereas it is not seen in complex atypical hyperplasia. These results are supported by the presence of p53 gene mutations in 90% of USCs and in only 10% to 20% of UECs.93–96 Nearly all UECs demonstrating p53 gene mutations are FIGO grade 3 (Figure 5, H). p53 immunohistochemistry is therefore not recommended when the differential diagnosis includes FIGO grade 3 UEC. p53 immunostaining is most likely to be of help when the differential diagnosis includes architecturally well-differentiated endometrioid adenocarcinomas, including those with papillary features,97 and glandular tumors with high nuclear grade. p53 immunostaining, along with MIB-1, p16, and ER and PR (see following), are also particularly useful for the distinction of intraepithelial serous carcinoma (endometrial intraepithelial carcinoma) and cytologically nonneoplastic proliferations, including metaplasias94 and radiation atypia. Immunohistochemical evaluation for p53 antibodies is generally straightforward, but there are several complexities to keep in mind. Patchy and/or focal and/or weak p53 labeling does not constitute overexpression and does not correlate with either p53 gene mutation or serous differentiation. The primary consideration should be whether Arch Pathol Lab Med—Vol 132, March 2008

there is p53 overexpression, which many pathologists define as expression in greater than 75% of tumor cell nuclei. Next, as many as 10% of USCs do not overexpress p53,93 they still differ from most FIGO grade 1 and 2 UECs in this respect because USCs, when p53 negative, are often entirely devoid of staining. UECs, in contrast, frequently show patchy, weak staining. Additional markers of interest include MIB-1, p16, ER, and PR (Figure 6, B). MIB-1 is especially useful when a serous diagnosis is considered and none of the tumor cells expresses p53. Diffuse, strong (⬎75% of cells) MIB-1 staining in this context would still support USC, especially if the expression profile for p16 and ER and PR were consistent with this diagnosis.95 p53 overexpression along with diffuse MIB-1 staining is much more commonly encountered in USC.95 Although p16 is well known as a surrogate marker for HPV in the lower genital tract, it is also characteristically diffusely and strongly expressed in USC,84,88 in which HPV infection is not considered to play an important role in pathogenesis. The pathways leading to p16 expression in USC have not been elucidated. More than 90% of USCs are strongly p16 positive, as compared with less than 10% of UECs and 50% of clear cell carcinomas.88 In contrast to that typically seen in USCs, p16 expression in UECs and clear cell carcinomas is almost always patchy and weak. Considerably greater degrees of p16 staining are seen in FIGO grade 3 UECs as compared with well-differentiated tumors. Estrogen receptor and PR expression is prevalent in FIGO grades 1 and 2 UECs, but it is generally weaker in serous and FIGO grade 3 UECs and negative in clear cell carcinomas.98–103 Presence of ␤catenin and loss of expression of phosphatase and tensin homolog (PTEN) are also features of endometrioid carcinoma (Figure 6, C and D). Suggested panel: p53, MIB-1, p16, ER, PR. Immunohistochemistry for DNA Mismatch Repair Proteins in Endometrial Carcinoma (Markers of Microsatellite Instability) Up to one quarter of UECs demonstrate high levels of microsatellite instability (MSI-H), which has been implicated in the pathogenesis of UECs but not USCs.104–106 We are now able to detect the expression status of 4 DNA mismatch repair proteins, the loss of which gives rise to MSI-H.107–111 The most common cause of abnormal DNA mismatch repair protein expression (involving as many as 80% of all MSI-H endometrial carcinomas) is hypermethylation of the hMLH1 promoter, which results in loss of MLH1 and PMS expression. Tumors that arise from this pathway occur sporadically. Most are well- or moderately differentiated UECs.110,112–115 Rare undifferentiated endometrial carcinomas have also been described.115 There may be a good clinical reason to identify MSI-H tumors—most affected patients (presumably those with hMLH1 promoter hypermethylation) have a superior prognosis when compared with patients with endometrial carcinomas that are not MSI-H.110 This situation stands in contrast to the remaining 10% of MSI-H endometrial cancers. These result from a mutation, usually of hMLH1 or hMSH2 and occur in the setting of hereditary nonpolyposis colorectal cancer. Mutation of hMLH1 usually gives rise to loss of MLH1 and PMS2 expression, whereas mutation in hMSH2 usually leads to loss of MSH2 and MSH6 expression. Identifying abnormal expression of these proteins may therefore help clinicians and geneticists determine whether a Immunohistochemistry in Gynecologic Pathology—Mittal et al 407

Figure 5. Uterine serous carcinoma (USC) versus uterine endometrioid carcinoma (UEC). USC shows diffuse and intense nuclear immunoreactivity for p53 (hematoxylin-eosin, original magnification ⫻100 [A]; p53, original magnification ⫻100 [B]), as does intraepithelial serous carcinoma (endometrial intraepithelial carcinoma) (hematoxylin-eosin, original magnifications ⫻100 and ⫻400 [inset] [C]; p53, original magnifications ⫻100 and ⫻400 [inset] [D]). USC can demonstrate a glandular architectural pattern (E; hematoxylin-eosin, original magnification ⫻100). Diffuse and intense p53 immunoreactivity in glandular USC (F; original magnification ⫻100) can provide support for this entity when atypical endometrial hyperplasia and endometrioid adenocarcinoma are considerations. Although low-grade endometrioid adenocarcinomas rarely overexpress p53, high-grade examples (G; hematoxylin-eosin, original magnification ⫻100) can show p53 overexpression (H; original magnification 408 Arch Pathol Lab Med—Vol 132, March 2008


Figure 6. Markers of emerging importance in distinguishing uterine endometrioid carcinoma (UEC) and uterine serous carcinoma (USC). Although USCs characteristically overexpress p53 (A; original magnification ⫻100)*, endometrioid adenocarcinomas, especially when gland-forming, frequently express estrogen receptors (B; original magnification ⫻100) and commonly show at least focal nuclear and cytoplasmic staining with anti– ␤-catenin (C; original magnification ⫻100) and loss of expression of phosphatase and tensin homolog (D; original magnification ⫻100). *A illustrates a mixed serous and endometrioid carcinoma in which the serous component overexpresses p53. D is reprinted with permission from the American Journal of Surgical Pathology.281

Table 2. p53†

Uterine Serous Versus Uterine Endometrioid Carcinoma* ER/PR

MIB-1

p16

Serous ⫹/⫺ ⫺/⫹ High ⫹ Endometrioid ⫺/⫹ ⫹/⫺ Low ⫺‡ * ER/PR indicates estrogen receptor/progesterone receptor; ⫹/⫺, mostly positive; and ⫺/⫹, mostly negative. † Only staining greater than 75% of cells is scored as positive. ‡ Patchy and weak staining is common. § Only nuclear staining is considered abnormal.

patient belongs to an hereditary nonpolyposis colorectal cancer kindred. There is now also mounting evidence that suggests that hereditary nonpolyposis colorectal cancer– associated endometrial cancers are more frequently poorly differentiated and of nonendometrioid type as compared with sporadic cancers.115,116 Interpreting immunostains111 for expression of MLH1, MSH2, MSH6, and PMS2 requires some practice because the goal is detection of expression loss. To score a protein as abnormally expressed, one should find strong and diffusely positive internal controls, such as the nuclei of endometrial stroma and nonneoplastic endometrium and verify complete absence of expression in tumor cell nuclei. A common pitfall is scoring protein expression loss when the internal controls are not optimal. Another common pitfall is scoring protein expression as retained when expression is encountered in hyperplasia but not in carcinoma. If no expression is found in a carcinoma, but DNA mismatch repair proteins appear retained in the accompanying hyperplasia, the case should be interpreted as DNA mismatch repair protein loss. Loss of MLH1 almost

␤-Catenin

Normal Normal or abnormal§

always accompanies loss of PMS2, and loss of MSH2 almost always accompanies loss of MSH6, with only occasional exceptions. The appearance of loss of MLH1 with MSH2 or loss of MLH1 with MSH6 should be questioned and the case reassessed. Occasional cases show loss of MSH6 alone or only PMS2. Suggested panel: MLH1, MSH2, MSH6, PMS2. Endometrial Stromal Versus Smooth Muscle Neoplasms CD10 and h-caldesmon are useful markers in this differential diagnosis (Figure 7, A through C; Figure 8, A and B). CD10 is expressed in endometrial stroma and endometrial stromal neoplasms, including low-grade endometrial stromal sarcoma (ESS) and endometrial stromal nodule117–119 (Table 3). Diffuse and strong membranous expression is found in only approximately 50% of classical-appearing ESSs. The remainder show patchy staining, with a cytoplasmic and membranous pattern. CD10 is also occasionally expressed in uterine smooth muscle neoplasms118 and UECs. Smooth muscle actin (SMA) can be expressed in both stromal and

←

⫻100). p53 expression in International Federation of Gynecology and Obstetrics (FIGO) grade 3 endometrioid adenocarcinoma is usually less diffuse and less intense when compared with USC. A through D reprinted with permission from the American Society for Investigative Pathology.95 E through H reprinted with permission from Churchill Livingstone.280 Arch Pathol Lab Med—Vol 132, March 2008


Figure 7. Endometrial stromal neoplasms. An endometrial stromal sarcoma (ESS) (A; hematoxylin-eosin, original magnification ⫻100) is negative for h-caldesmon (B; original magnification ⫻100). Endometrial stromal sarcomas nearly always express CD10 (C; original magnification ⫻100) and estrogen receptor (D; original magnification ⫻100) and progesterone receptors. Several histologic mimics of metastatic ESS, including solitary fibrous tumor, can express progesterone receptors (E; original magnification ⫻400) and CD10 as well. Although many ESSs express CD10 strongly and diffusely, some express CD10 in a patchy pattern, which overlaps with that seen in solitary fibrous tumor and hemangiopericytoma, both tumors with a staghorn vascular pattern. A and B reprinted with permission from Churchill Livingstone.280 C through E reprinted with permission from Modern Pathology.131

smooth muscle cells, but a lack of desmin expression is consistent with endometrial stromal differentiation in the right context. h-Caldesmon, an actin and tropomyosinbinding protein, has also been reported to support smooth muscle differentiation.120,121 h-Caldesmon, more specific for

smooth muscle differentiation when compared with desmin, distinguishes uterine smooth muscle tumors from conventional endometrial stromal tumors, which uniformly lack h-caldesmon reactivity (Figure 7, A and B). Endometrial stromal tumors almost always express ER and

Figure 8. Endometrial stromal neoplasms with smooth muscle differentiation. A, Areas resembling endometrial stroma (left) contrast with areas resembling smooth muscle (right) (hematoxylin-eosin, original magnification ⫻100). B, CD10 marks endometrial stromal cells, whereas muscle markers, such as h-caldesmon, mark zones showing smooth muscle differentiation (CD10, original magnification ⫻100). Endometrial stromal neoplasms are in general diagnosed when conventional-appearing endometrial stroma is present; the diagnosis should not be abandoned solely because of divergent differentiation, such as smooth muscle differentiation, illustrated here. Reprinted with permission from Churchill Livingstone.280 410 Arch Pathol Lab Med—Vol 132, March 2008


Table 3.

Endometrial Stromal Versus Smooth Muscle Tumor*

Disease Type

SMA

Desmin h-Caldesmon

CD10

Endometrial stromal ⫹/⫺ R N ⫹/⫺ Smooth muscle ⫹ ⫹ ⫹ ⫺/⫹ * SMA indicates smooth muscle actin; ⫹/⫺, mostly positive; R, rare; N, negative; ⫹, positive; and ⫺/⫹, mostly negative.

PR, as can uterine smooth muscle tumors. WT1 expression has been described in endometrial stromal and smooth muscle tumors as well.122 Several endometrial stromal tumor variants exist: smooth muscle variant (also referred to as mixed endometrial stromal and smooth muscle tumor and stromomyoma),123,124 fibromyxoid variant,123,125 sex cord variant, including the ‘‘uterine tumor resembling ovarian sex cord tumor,’’ 125,126 and variants including endometrioid glands or epithelioid cells.127 Understanding the immunophenotype of these tumors is based on the acknowledgment that the variant elements often lose the phenotype of endometrial stroma and acquire the phenotype of the corresponding variant or metaplastic element.123 For example, the smooth muscle in a smooth muscle variant of endometrial stromal nodule expresses muscle markers and may be negative for CD10.118,124 The endometrioid glands in an ESS, epithelioid variant, would express epithelial markers, such as EMA but not necessarily CD10. Similarly, the sex cord component of an endometrial stromal nodule, sex cord variant, might express inhibin and lose CD10 expression.128 Hybrid forms also exist, further complicating interpretation; some stromal neoplasms with sex cord features contain elements that coexpress muscle markers and cytokeratins.118 Suggested panel: CD10, desmin, h-caldesmon. ESS Versus Soft Tissue Neoplasms With a Hemangiopericytomatous Vasculature Endometrial stromal sarcomas can metastasize decades after initial presentation (particularly to the lungs) and can arise as primary tumors in extrauterine locations (especially in the ovaries and retroperitoneum). Given this and the observation that many endometrial stromal neoplasms have a pericytomatous vasculature, numerous tumors enter into the differential diagnosis. These include monophasic synovial sarcoma, solitary fibrous tumor, and hemangiopericytoma, among others. Nearly all ESSs, including variants and extrauterine tumors, express ER (Figure 7, D), PR, and CD10, at least focally. Of interest, more than 50% express SMA,118,128–131 and nearly a quarter express AE1/AE3 cytokeratin.131,132 Epithelial membrane antigen is negative,129,131 except in the endometrioid tubules of endometrial stromal tumors containing these structures. The patchy, cytoplasmic and membranous CD10 expression pattern seen in about half of ESSs is also encounTable 4.

tered in stromal sarcoma mimics, including substantial numbers of hemangiopericytomas and solitary fibrous tumors.131 CD34 expression, however, is nearly universal in hemangiopericytomas and solitary fibrous tumors but is not seen in ESS.118,131 Therefore, one should test for CD10 expression along with ER and CD34 (Table 4). Even if only focally CD10⫹, essentially all stromal sarcomas express ER, and almost none express CD34. Solitary fibrous tumors and hemangiopericytomas, in contrast, express CD34 but not ER. Progesterone receptor can be expressed in both stromal sarcomas and in nearly 50% of solitary fibrous tumors (Figure 7, E) and hemangiopericytomas.131 Suggested panel: CD10, ER, CD34. Uterine Smooth Muscle Neoplasms Leiomyoma and Leiomyosarcoma. One of the most difficult differential diagnoses in gynecologic pathology concerns the distinction of atypical leiomyomas from leiomyosarcomas. Morphologic criteria are useful and remain the standard, but the relative deficiencies of this approach are well known. Expression of ER, PR, p53, Bcl-2, and MIB-1 in uterine smooth muscle tumors has been studied.133–136 Leiomyosarcomas express more p53 and MIB-1 than leiomyomas but less Bcl-2 and ER and PR. In the presence of nuclear atypia, MIB-1 and/or p53 expression of more than 15% favors a diagnosis of leiomyosarcoma over smooth muscle tumors of uncertain malignant potential or cellular leiomyoma.137 MIB-1 expression may be useful in confirming the impression of mitotic activity, especially in poorly preserved specimens in which the distinction of mitotic figures from apoptotic bodies is not straightforward. Expression of ER, PR, p53, and MIB-1 have prognostic significance in leiomyosarcoma,136 but these lose significance in multivariate models in which stage remains the most important prognostic factor. Epithelioid Smooth Muscle Tumors. Epithelioid smooth muscle tumors possess some characteristics that separate them from the more common smooth muscle tumors composed of spindle-shaped cells. Their appearance can simulate a number of neoplasms with epithelioid features, including primary and metastatic carcinomas, melanomas, trophoblastic tumors, endometrial stromal tumors, and tumors with sex cord differentiation. Although using immunohistochemistry can narrow the differential diagnosis, its use is complicated in this group of tumors. The limited immunohistochemistry data for uterine epithelioid smooth muscle tumors indicate that they can demonstrate cytokeratin expression, at least focally.118,138 Carcinomas, on the other hand, often demonstrate stronger and more diffuse anticytokeratin immunoreactivity. Using desmin alone without a panel of markers is also subject to problems because many uterine epithelioid smooth muscle tumors lose diffuse desmin and h-caldesmon expression.118 A reasonable panel for this differential diagnosis would include CAM 5.2 cytokeratin, AE1/AE3 cy-

Endometrial Stromal Sarcoma Versus Pericytomatous Tumor* CD10

ER

Endometrial stromal sarcoma ⫹ Solitary fibrous tumor/hemangiopericytoma ⫺/⫹ Monophasic synovial sarcoma N * ER indicates estrogen receptor; PR, progesterone receptor; ⫹, positive; N, Arch Pathol Lab Med—Vol 132, March 2008

PR

CD34

AE1/AE3

⫹ ⫹ N ⫺/⫹ N ⫺/⫹ ⫹ N N N N ⫹/⫺ negative; ⫺/⫹, mostly negative; and ⫹/⫺, mostly positive.


tokeratin, desmin, h-caldesmon, and SMA. S100 and CD10 could be added if melanoma and ESS were considered. Perivascular Epithelioid Cell Tumor. The morphology of perivascular epithelioid cell tumors (PEComas)139 often overlaps with that of epithelioid smooth muscle tumors, especially those with clear cytoplasm. PEComas, related to angiomyolipoma and lymphangioleiomyomatosis, are composed of specialized or hybrid muscle cells that coexpress muscle markers and some of those associated with melanocytic differentiation, namely HMB-45 and Melan-A.139–141 Uterine smooth muscle neoplasms can occasionally express HMB-45 and/or Melan-A142,143 but only in a very restricted distribution. PEComas, frequently desmin negative, tend to show much stronger expression of these markers. Furthermore, it is not known whether there are important clinical differences between uterine PEComas and conventional uterine epithelioid smooth muscle tumors. Suggested panel: desmin, HMB-45, Melan-A. c-Kit (CD117). Some studies have reported negative results for c-Kit in uterine mesenchymal tumors,118,144,145 but other describe c-Kit positivity in leiomyosarcomas and carcinosarcomas.145–147 Importantly, activating mutations of the c-kit gene were not found in immunohistochemically positive tumors.147 c-Kit immunostaining should therefore not be performed for determining candidacy for treatment with imatinib mesylate (Gleevec, Novartis, East Hanover, NJ). We do recommend c-Kit analysis, however, along with CD34 and desmin, when the differential diagnosis includes both a gynecologic smooth muscle neoplasm and a gastrointestinal stromal tumor.118,148 Suggested panel: desmin, CD34, CD117. Undifferentiated Endometrial Carcinoma Versus Undifferentiated Uterine Sarcoma Versus Carcinosarcoma If clearly defined and separable carcinomatous and sarcomatous components are not seen on examination of routinely stained slides, it is often difficult or impossible to substantiate a diagnosis of carcinosarcoma (malignant mixed mu¨llerian tumor). In some monophasic tumors showing pleomorphism, using an antibody panel that includes cytokeratins and a variety of mesenchymal-associated markers often reveals a confusing immunophenotype—coexpression of epithelial and mesenchymal markers or complementary expression of both. CD10 antibodies are not recommended in this setting because CD10 immunoreactivity is not indicative of endometrial stromal differentiation when the tumor in question is cytologically high grade. If one encounters distinct, geographic zones that express cytokeratins exclusively and separate, distinct zones that express mesenchymal markers exclusively, it is reasonable to consider a diagnosis of carcinosarcoma. The very rare undifferentiated endometrial carcinoma expresses cytokeratins and/or EMA only focally and lacks ER and PR expression; they have also been reported to lose expression of MLH.115,149 Otherwise, diffuse, strong keratin expression supports carcinoma and diffuse muscle marker expression without keratin immunoreactivity supports a sarcoma with a myogenous phenotype. Other patterns of immunoreactivity are probably not informative. Emerging data support the previously discredited idea that heterologous differentiation in carcinosarcoma is a poor prognostic indicator.150 In this regard, immunohistochemistry is a powerful method of confirming an impression of rhabdomyoblastic differentiation. Myogenin or 412 Arch Pathol Lab Med—Vol 132, March 2008

myoD1, sensitive and specific markers for skeletal muscle differentiation, can be used for this purpose.151–153 Considerations about a tumor whose morphology is undifferentiated include undifferentiated primary or metastatic carcinomas, melanoma, lymphoma/leukemia, and undifferentiated uterine sarcoma. If there is concern about these tumors, it is reasonable to evaluate with antibodies against cytokeratin, S100, leukocyte common antigen, CD43, and a muscle marker. Suggested panel: cytokeratin, desmin, S100; consider myogenin or myoD1 to confirm rhabdomyoblastic differentiation; consider leukocyte common antigen and CD43 to exclude lymphoma and leukemia when appropriate. Early Complete Hydatidiform Mole Versus Partial Mole and Hydropic Abortus The morphologic criteria for distinguishing complete hydatidiform moles from mimickers are robust, particularly when the tissue is derived from a second trimester conceptus. Detection of abnormal gestations in the first trimester has led to diagnostic difficulties, however, because increased villous size and trophoblastic proliferation are less pronounced than in tissue derived from more advanced gestations. Immunohistochemical evaluation with antibodies against the p57 protein, a maternally transcribed gene product, has emerged as a useful adjunct to morphologic, flow cytometric, and cytogenetic study of molar tissue. Whereas p57 protein is expressed in intermediate trophoblasts of complete moles, partial moles, and nonmolar abortuses, only complete hydatidiform moles lack p57 expression in cytotrophoblasts and villous stromal cells.154–158 Suggested antibody: p57. Placental Site Nodule Versus Squamous Cell Carcinoma Placental site nodules are composed of intermediate trophoblast cells within a nodular, hyalinized stroma. In curettage specimens, these lesions can be confused with keratinizing squamous carcinoma. An immunohistochemical panel with inhibin, Ki-67, CK18, and p16 is suggested. CK18 and inhibin, although expressed in trophoblastic lesions, are generally not expressed diffusely in squamous neoplasms. p16 is reportedly negative in trophoblastic lesions.159 The Ki-67 index of cervical squamous carcinomas, which characteristically express p16, is greater than 60%,160 whereas the Ki-67 index in a placental site nodule is not more than 10% to 15%.161 Suggested panel: inhibin, CK18, p16, MIB-1. Placental Site Trophoblastic Tumor Versus Placental Site Nodule Both placental site trophoblastic tumor cells and intermediate cells in a placental site nodule stain with cytokeratin and frequently with human placental lactogen (hPL) (Figure 9). The Ki-67 index (percentage of positively staining cells) is close to zero in placental site nodules; placental site trophoblastic tumors have an index of 14% (⫾7%).162 Exaggerated implantation sites also have a low Ki-67 index. A new strategy for distinguishing placental site nodule and placental site trophoblastic tumor is to use p63 immunohistochemistry; p63 is expressed in the intermediate trophoblasts of placental site nodule but not in placental site trophoblastic tumor.163 One should be aware that the epithelioid trophoblastic tumor, a cousin to placental site trophoblastic tumor, typically expresses p63. If Immunohistochemistry in Gynecologic Pathology—Mittal et al

Figure 9. Immunostaining algorithm using a panel of markers in the differential diagnosis of trophoblastic lesions. The algorithm begins with immunostaining with cytokeratin (CK) 18, p16, and HLA-G antibodies. If CK18 and HLA-G are both diffusely positive and p16 is negative, the lesion is trophoblastic. If p63 is selectively stained in mononucleate trophoblast corresponding to cytotrophoblast and human chorionic gonadotropin (hCG) is selectively stained in syncytiotrophoblast, the lesion is choriocarcinoma. If p63 is negative and human placental lactogen (hPL) is diffusely positive, the lesion is either an exaggerated placental site (EPS) or a placental site trophoblastic tumor (PSTT). These lesions can be distinguished based on the Ki-67 labeling index. If p63 is diffusely positive and only focally positive for hPL, the lesion is either a placental site nodule (PSN) or an epithelioid trophoblastic tumor (ETT). These lesions can be distinguished based on the Ki-67 labeling index. ⫹⫹⫹ indicates diffusely positive; ⫹⫹, patchy staining; ⫹, focally positive;; and ⫺, negative. Courtesy of Dr Ie-Ming Shih.

the lesion in question expresses p63 and has a low proliferative rate, a diagnosis of placental site nodule should be considered, but if the proliferative rate exceeds approximately 10%, a diagnosis of epithelioid trophoblastic tumor should be entertained. Suggested antibodies: MIB-1; consider p63. Choriocarcinoma Versus Placental Site Trophoblastic Tumor Versus Poorly Differentiated Neoplasm Choriocarcinoma is a biphasic tumor consisting of syncytiotrophoblast cells and mononuclear cells including both intermediate trophoblasts and cytotrophoblasts. A placental site trophoblastic tumor may enter the differential diagnosis when multinucleated giant cells are present and serum hCG levels are elevated. Choriocarcinomas contain numerous syncytiotrophoblasts, intimately associated with mononuclear trophoblasts. In contrast, some placental site trophoblastic tumors contain randomly distributed syncytiotrophoblasts amongst sheets of intermediate trophoblasts. Because the extent and distribution of hCG immunoreactivity is a rather good indication of the number and location of syncytiotrophoblasts, it can be used to distinguish choriocarcinoma and placental site trophoblastic tumor. An immunohistochemical panel of hCG, CK18, hPL, and inhibin is recommended for distinguishing a trophoblastic neoplasm from a poorly differentiated carcinoma (Figure 9). Trophoblastic tumors express CK18 diffusely, but squamous lesions do not. Inhibin is a generally good all-purpose trophoblastic marker that is not expressed in carcinomas that mimic trophoblastic tumors, and hPL marks a large number of trophoblastic tumors as well. Evaluation of the Ki-67 index is helpful as placental site trophoblastic tumors have a low index of 14% (⫾7%), whereas choriocarcinoma and carcinomas frequently have an index greater than 60%.159,162 Immunohistochemical evaluation cannot distinguish between gestational choriocarcinoma and a germinal choriocarcinoma. Study with immunohistochemistry is also not useful for the separation of gestational choriocarcinoma from a somatic carcinoma that contains trophoblastic eleArch Pathol Lab Med—Vol 132, March 2008

ments, which can be seen in cervical squamous carcinoma and transitional cell carcinoma of the bladder in addition to others.164,165 It should not be surprising that the syncytiotrophoblasts encountered in occasional carcinomas express hCG as well. Suggested panel: hCG, CK18, MIB-1, inhibin; consider hPL. VULVA AND VAGINA Vulvovaginal Mesenchymal Lesions A wide variety of mesenchymal lesions can arise in the vulvovaginal region.166–168 Lesions specific to, relatively specific to, or characteristic of this site include aggressive angiomyxoma, angiomyofibroblastoma, cellular angiofibroma, superficial myofibroblastoma of the lower female genital tract, fibroepithelial stromal polyp, and smooth muscle tumors.169–190 In addition, any soft tissue tumor can potentially arise in the vulvovaginal region. Most of the mesenchymal lesions that are encountered here are morphologically bland, and distinction between the various entities may be problematic. Immunohistochemistry plays a limited role, but there are occasions when markers may be useful. Almost all of the aforementioned lesions are positive with ER, PR, and vimentin. Most exhibit desmin positivity and ␣-smooth muscle actin (␣-SMA), and CD34 may be positive or negative. Therefore, with regards to the immunophenotype, there is considerable overlap between the various entities. Cellular angiofibroma differs from the others in that, although vimentin, ER, and PR positive, it is typically desmin and ␣-SMA negative because this lesion exhibits fibroblastic rather than myofibroblastic differentiation.181–183 As a result, negative staining with desmin may be a useful diagnostic pointer, although a minority of cases of the other lesions mentioned are also negative. Positivity of aggressive angiomyxoma with ER and PR191 has resulted in the use of gonadotropinreleasing hormone agonists in the management of lesions that are not amenable to surgical resection. Administration of these agents may result in marked shrinkage of aggressive angiomyxomas.192,193 Immunohistochemistry in Gynecologic Pathology—Mittal et al 413

Immunohistochemical staining with HMGA2 may be of value in the diagnosis of aggressive angiomyxoma.194 Aggressive angiomyxoma usually exhibits nuclear positivity, whereas most of the other vulvovaginal mesenchymal lesions are negative. Staining with HMGA2 may also be of value in the assessment of margins in resection specimens and in the determination of the presence or absence of residual disease in wider excisions. It is stressed that any mesenchymal lesion, benign or malignant, may potentially occur in the vulvovaginal region. The immunophenotype of these does not differ from when they occur at more usual sites. Recently, extragastrointestinal stromal tumors have been described arising in the vulvovaginal region.195 Similar to their gastrointestinal counterparts, they are typically c-Kit and CD34 positive but negative with desmin and hormone receptors. They contain activating c-kit mutations.195 Suggested panel: ER, PR, desmin, ␣-SMA, HMGA2. Vulvar Intraepithelial Neoplasia The value of markers in the distinction between dysplastic squamous lesions and nondysplastic mimics is covered more fully in the section on the cervix. In the vulva, the morphologic features of koilocytosis, the hallmark of HPV infection, may not be as obvious as in the cervix. Consequently it may be difficult to diagnose a viral-induced lesion. Immunohistochemical staining with the proliferation marker MIB-1 may be of value. In true HPV infection of the vulva, MIB-1 positive clusters are present in the middle and upper thirds of the epithelium.196,197 The cells of high-grade vulvar intraepithelial neoplasia (VIN 2 to 3) express MIB-1 throughout much of the full epithelial thickness. This may be of value in the distinction between high-grade VIN and atrophic squamous epithelium. p16 may also be of use. The most common type of VIN (undifferentiated or bowenoid VIN) is associated, in most cases, with high-risk HPV. As discussed in the ‘‘Cervix’’ section, p16 may be regarded as a surrogate marker of the presence of high-risk HPV. Therefore, most cases of undifferentiated VIN are p16 positive.198,199 In contrast, differentiated VIN is not typically associated with HPV and is usually p16 negative.198,199 It has been claimed that p53 may assist in the diagnosis of differentiated VIN.200 This may be a difficult diagnosis morphologically because the features are subtle. Intense positive nuclear staining for p53 in the basal and suprabasal cells, usually secondary to p53 mutation, is characteristic of differentiated VIN.200 However, it is clear that p53 positivity may also occur in the basal cell layers of nonneoplastic lesions such as lichen sclerosis and inflammatory conditions because of mechanisms other than p53 mutation.201 p16 may be of value in the distinction between HPVrelated invasive vulvar squamous carcinomas (diffuse p16 positivity) and the more common non–HPV-related squamous carcinomas (p16 negative or focally positive, especially at the advancing edge of the tumor).198 Suggested panel: MIB-1, p16, p53. Vulvar Paget Disease Immunohistochemistry may be useful both in the diagnosis of vulvar Paget disease and in the distinction of primary from secondary Paget disease. The neoplastic cells of Paget disease are positive with CAM 5.2 (Figure 10, A) and CEA,202 helping to exclude mimics such as pagetoid Bowen disease, melanocytic lesions, and mycoses 414 Arch Pathol Lab Med—Vol 132, March 2008

fungoides. The cells of primary vulvar Paget disease are typically positive for CK7 (Figure 10, B) and GCDFP-15 and commonly also react with HER-2/neu (Figure 10, C) and androgen receptor.203–205 They are typically ER and PR negative. As well as being of use in diagnosis, these markers may assist in the assessment of margins and in the identification of small foci of dermal invasion. Most cases of pagetoid Bowen disease are CK7 negative, although CK7 positivity has been described in a small number of cases.206 Cytokeratin 20 is typically negative or focally positive in primary vulvar Paget disease (Figure 10, D). Diffuse strong CK20 positivity in vulvar Paget disease raises the possibility of spread from an internal organ such as the colorectum or urinary bladder because carcinomas arising at these sites are commonly CK20 positive. Normal Merkel cells are also CK20 positive. Vulvar Paget disease secondary to an underlying urinary bladder carcinoma is typically uroplakin-III positive, and Paget disease secondary to a colorectal adenocarcinoma is usually MUC2 and CDX-2 positive.207–209 It has been suggested that p53 positivity of the intraepithelial cells of primary vulvar Paget disease may be associated with an increased likelihood of an underlying invasive malignancy.210 On the basis of positivity of Paget cells with CK19 and of the associated compressed keratinocytes with CK15, it has recently been suggested that extramammary Paget disease is a proliferation of adnexal stem cells residing in the infundibulo-sebaceous unit of hair follicles.211 Suggested panel: CAM 5.2, CEA, CK7, CK20, GCDFP15, HER-2/neu, androgen receptor. CERVIX Preinvasive Cervical Squamous Lesions The value of proliferation markers, such as MIB-1 (which reacts against the Ki-67 antigen), in the assessment of preinvasive cervical squamous lesions has been widely investigated.212–216 MIB-1 is of no value in the distinction between koilocytosis and cervical intraepithelial neoplasia (CIN) 1 and in the separation of adjacent lesions in the CIN spectrum. Its main value is in the distinction between high-grade CIN (CIN 2 and 3) and mimics such as atrophic squamous epithelium, transitional metaplasia, and immature squamous metaplasia. In normal cervical squamous epithelium, nuclear MIB-1 staining is confined to the parabasal cells, whereas in CIN 3 it is full thickness (Figure 11, A; Figure 12, A). There is also a high proliferation index in CIN 2. Atrophic squamous epithelium exhibits minimal proliferative activity, with only focal staining of the basal and parabasal cells (Figure 11, B), and the proliferation index is low in transitional metaplasia and immature squamous metaplasia. MIB-1 may be of value in the interpretation of cauterized squamous epithelium at resection margins because the normal patterns of immunoreactivity are typically retained, even with marked cautery artefact.212 Tangential sectioning of normal squamous epithelium or partial denudation of the surface epithelium may result in a false impression of MIB-1–positive cells in the upper aspects of the epithelium. p16 may be of value in the diagnosis of high-grade CIN. p16 is a cyclin dependent kinase-4 inhibitor217–219 and specifically binds to cyclin D–cyclin dependent kinase 4/6 complexes to control the cell cycle at the G1-S interphase. p16 is integral to p-retinoblastoma (p-Rb)–mediated control of the G1-S phase transition of the cell cycle; it puts a Immunohistochemistry in Gynecologic Pathology—Mittal et al

Figure 10. Primary vulvar Paget disease exhibiting strong positive staining with CAM 5.2 (A; original magnification ⫻100), cytokeratin (CK) 7 (B; original magnification ⫻100), and HER-2/neu (C; original magnification ⫻100). There is focal weak CK20 immunoreactivity (D; original magnification ⫻100).

brake on the cell cycle by inactivating the cyclin dependent kinases that phosphorylate Rb protein. In cervical lesions associated with high-risk HPV infection, there is functional inactivation of Rb by HPV E7 protein with a resultant accumulation of p16 protein, because normally Rb inhibits transcription of p16.217–219 In most cases, diffuse p16 positivity in the cervix can be regarded as a surrogate marker of the presence of high-risk HPV (Figure 12, B). However, it is clear that focal or even diffuse p16 expression in the cervix and other tissues may occur as a result of non– HPV-related mechanisms.220 The role of p16 as a diagnostic aid in gynecologic pathology has recently been reviewed.221 There is diffuse p16 staining, nuclear, cytoplasmic, or a combination, involving the full thickness of the epithelium in most cases of CIN 2 and 3 because of the presence of high-risk HPV.222–224 However, although diffuse p16 staining involving the full thickness of the epithelium is a relatively specific indicator of high-grade CIN, a negative reaction does not exclude this because some cases of high-grade CIN are negative.223–225 It has been suggested that p16 may assist in identifying low-grade CIN lesions that are associated with high-risk HPV and that have an increased risk of progression. In one study, almost all cases of CIN 1 associated with high-risk HPV were p16 positive, whereas a large majority of cases not associated with high-risk HPV were negative.225 In most CIN 1 cases that are p16 positive (the percentage of positive cases has varied widely between studies222–225), immunoreactivity has been confined to the lower third to half of the epithelium. There is minimal or negative p16 staining in normal, atroArch Pathol Lab Med—Vol 132, March 2008

phic, and inflamed cervical squamous epithelium. It can be appreciated that, in the evaluation of cervical squamous lesions, MIB-1 and p16 have broadly similar uses and in practice the 2 markers are often best used together because they are complementary to each other. Suggested panel: MIB-1, p16. Distinction of Cervical AIS From Benign Mimics In the World Health Organization classification, the terms adenocarcinoma in situ and glandular dysplasia are used to encompass the spectrum of premalignant endocervical glandular lesions.226 In the United Kingdom, cervical glandular intraepithelial neoplasia is the most commonly used term; high-grade cervical glandular intraepithelial neoplasia equates to AIS and low-grade cervical glandular intraepithelial neoplasia to glandular dysplasia. The distinction between AIS and benign mimics, especially tuboendometrial metaplasia (TEM) and endometriosis, although usually straightforward, may on occasions be problematic. The combination of MIB-1, Bcl-2, and p16 may be of value.227–234 The MIB-1 proliferation index is typically less than 10% in TEM and endometriosis, whereas in AIS it is generally greater than 30%; in the majority of cases it is much greater with most nuclei exhibiting positivity (Figure 12). It is usually not necessary to undertake a formal count as there are typically only scattered positive nuclei in TEM and endometriosis, whereas in AIS most nuclei are positive. However, in some instances there is overlap with occasional cases of AIS having a low proliferation index and some benign lesions, especially enImmunohistochemistry in Gynecologic Pathology—Mittal et al 415

Figure 11. Cervical intraepithelial neoplasia 3 exhibits full-thickness immunoreactivity with MIB-1 (A), whereas atrophic squamous epithelium is negative (B) (original magnifications ⫻100). Figure 12. Cervical adenocarcinoma in situ exhibiting a high MIB-1 proliferation index (A) and diffuse p16 positivity (B) (original magnifications ⫻100). Figure 13. Prostatic metaplasia in cervix exhibiting positivity with prostatic acid phosphatase (A; original magnification ⫻100). Staining with 34␤E12 highlights the basal layer of the glandular epithelium (B; original magnification ⫻100).



dometriosis, exhibiting a proliferation index in excess of 30%, meaning that, in an individual case, MIB-1 may not be of value. Bcl-2 may be useful as TEM and endometriosis typically exhibit diffuse cytoplasmic positivity, whereas AIS is generally negative.230,231 Adenocarcinoma in situ usually, although not always, exhibits p16 positivity because of the presence of high-risk HPV.230,232–235 Some cases of TEM and endometriosis are p16 positive but usually focally so, in contrast to the diffuse staining seen in AIS. Vimentin may be of value as TEM and endometriosis typically exhibit cytoplasmic positivity, whereas AIS is negative.235 Similarly TEM and endometriosis usually exhibit nuclear ER positivity, whereas AIS is generally negative or focally positive. Monoclonal CEA may be of value in that cytoplasmic positivity is characteristic of a premalignant or malignant glandular lesion.235,236 However, some cases of AIS are CEA negative, and conversely there may be luminal positivity in benign glandular lesions and even normal endocervical glands. The markers discussed may be useful in distinguishing between cauterized normal endocervical glands or cauterized TEM and the cauterized glands of AIS at loop resection margins. Glandular dysplasia (which is rarely diagnosed in pure form without coexistent AIS) has not been extensively investigated using the aforementioned markers and would be expected to exhibit a relatively low MIB-1 proliferation index. However, p16 may be of use in that most cases of glandular dysplasia studied have been positive because of their association with high-risk HPV.230 A variety of other markers have been investigated in an attempt to distinguish between AIS and benign mimics, including antibodies against p53, CD44, mucus-related antigens, and blood group antigens.236–241 However, these markers have not gained a foothold in routine pathology practice. Suggested panel: MIB-1, Bcl-2, p16, monoclonal CEA. Markers of Cervical Mesonephric Lesions CD10 has recently been described as a marker of mesonephric glands within the cervix and elsewhere in the female genital tract.242–244 Cervical mesonephric remnants, in most cases, exhibit luminal CD10 positivity. It is relatively rare for other benign cervical glandular lesions to be CD10 positive. However, cervical and endometrial adenocarcinomas may be positive,244 although not typically with a luminal pattern. Therefore, CD10 immunoreactivity in a cervical adenocarcinoma cannot be taken as proof of a mesonephric origin. CD10 is a widely used marker of normal and neoplastic endometrial stroma.245 However, the cervical stroma immediately surrounding endocervical glands is CD10 positive, illustrating that in the cervix CD10 is of limited value in helping to confirm a diagnosis of endometriosis.242 Other markers that are positive in benign mesonephric remnants and mesonephric adenocarcinomas, in a variable percentage of cases, include androgen receptor, vimentin, calretinin, and inhibin.246 Estrogen receptor, PR, and monoclonal CEA are typically negative. Diffuse p16 positivity has been described in cervical mesonephric glands,247 presumably because of non–HPV-related mechanisms. Suggested panel: CD10, vimentin, calretinin, ER. Arch Pathol Lab Med—Vol 132, March 2008

Cervical Minimal Deviation Adenocarcinoma (Adenoma Malignum) Minimal deviation adenocarcinoma is an extremely well-differentiated adenocarcinoma that may be confused with normal endocervical glands or a variety of benign cervical glandular lesions, especially in small biopsy specimens. The most common morphologic subtype is the mucinous variant, known as adenoma malignum. Gastric mucins are present in many cases of adenoma malignum. HIK1083, a monoclonal antibody against gastric gland mucins, is positive in a proportion of cases and, as a consequence, may be useful in diagnosis.248,249 Normal endocervical glands are almost always negative, although focal areas of positivity may be present in usual cervical adenocarcinomas.250 Cytoplasmic monoclonal CEA positivity may be of value in distinguishing adenoma malignum from normal or hyperplastic endocervical glands, which are usually CEA negative.84,85 However, some cases of adenoma malignum are negative,251,252 and conversely there may be luminal positivity in hyperplastic or normal endocervical glands. In contrast to most usual cervical adenocarcinomas, adenoma malignum is often p16 negative because many cases are not associated with high-risk HPV.253 The benign endocervical glandular lesion ‘‘lobular endocervical glandular hyperplasia, not otherwise specified’’ also, in some cases, exhibits a pyloric gland immunophenotype and is positive with HIK1083.254 It has been suggested that this may represent a precursor of adenoma malignum, although this is unproven.255,256 p16 positivity, unassociated with the presence of HPV, has been demonstrated in cases of lobular endocervical glandular hyperplasia, not otherwise specified.256 It has been suggested that a combination of ER and ␣SMA immunohistochemistry may be useful in the distinction between adenoma malignum and normal or hyperplastic endocervical glands.257 With normal and hyperplastic glands, the stroma is ER positive and largely ␣SMA negative. Because of the desmoplastic stromal response in adenoma malignum, the stromal cells are largely ER negative and there are increased numbers of ␣-SMA–positive myofibroblasts. Suggested panel: HIK1083, monoclonal CEA, ER, ␣SMA. Prostatic Tissue in the Cervix Ectopic prostatic tissue has been described in the cervix in the last few years.258,259 This is possibly more common than is realized because cases may go unrecognized if the diagnosis is not considered and appropriate immunohistochemistry performed. The prostatic tissue is usually located deep within the cervical stroma, either at the transformation zone or on the ectocervix, and there is almost always a combination of glandular and squamous elements. Typically, a double cell layer of glandular epithelium is present, similar to the eutopic prostate. Confirmation is easy, once the diagnosis is considered, using antibodies against prostate-specific antigen (PSA) and prostatic acid phosphatase (PrAP; Figure 13, A). However, PSA may be negative and PrAP staining may be focal. 34␤E12 highlights the basal cell layer of glandular epithelium (Figure 13, B), and ER is positive in the squamous elements.259 The basal cell layer of the glandular epithelium is usually CD10 positive and the glandular elements are Immunohistochemistry in Gynecologic Pathology—Mittal et al 417

androgen receptor positive.259 ␣-Methylacyl-CoA racemase has been positive in most cases tested.259 Suggested panel: PSA, PrAP, 34␤E12. Distinction Between Endometrial and Cervical Adenocarcinoma Adenocarcinoma may be present in preoperative endometrial and cervical biopsies and ascertaining the site of origin may be difficult. Problems may also occur in a hysterectomy specimen when tumor involves both the uterine corpus and the cervix. In general, the morphology differs between a usual cervical adenocarcinoma and an endometrial adenocarcinoma of endometrioid type, but there may be considerable overlap. A panel of markers comprising ER, vimentin, p16, and monoclonal CEA is of value.260–266 Endometrial adenocarcinomas of endometrioid type typically exhibit diffuse nuclear ER and cytoplasmic vimentin positivity. Carcinoembryonic antigen and p16 are usually negative or focally positive, although the squamous elements that are common in these neoplasms may stain. In contrast, cervical adenocarcinomas are usually, but not always, diffusely positive with CEA and p16, the latter because of the association with high-risk HPV. Vimentin is usually negative, and ER is typically negative or there is focal weak positivity. In occasional endometrioid adenocarcinomas of the uterine corpus, there is diffuse p16 positivity, and uterine serous carcinoma (similar to ovarian serous carcinoma) is often diffusely positive,266–268 presumably because of non–HPV-related mechanisms. It is stressed that the panel of markers discussed is only of value in distinguishing a usual cervical adenocarcinoma from an endometrial adenocarcinoma of endometrioid type. The panel of markers also assists in the recently highlighted cases of subtle cervical stromal invasion by endometrioid adenocarcinoma of the uterine corpus.269 In such cases, the tumor within the cervix may be morphologically bland without a stromal reaction and can mimic cervical AIS, a primary cervical adenocarcinoma, or even cervical mesonephric remnants. In those rare cases in which an endometrioid adenocarcinoma of the uterine corpus and a premalignant or malignant endocervical glandular lesion coexist, the panel of markers discussed helps to clarify the relationship between the 2 neoplasms. The question also arises as to the immunophenotype of a mucinous adenocarcinoma of the endometrium and an endometrioid adenocarcinoma of the cervix. One study that addressed this issue found that if a tumor exhibited diffuse ER and vimentin positivity, then it was almost certainly of endometrial origin.270 We stress that in any individual tumor, unexpected staining reactions may occur with one or more of the markers discussed. This can result in potential diagnostic problems and illustrates that the immunophenotype is always to be interpreted in light of the clinical, radiologic, gross pathologic, and microscopic findings. Suggested panel: ER, vimentin, monoclonal CEA, p16. Cervical Neuroendocrine Neoplasms Establishing a diagnosis of a small cell or large cell neuroendocrine carcinoma is important because these are highly aggressive neoplasms that may be managed differently from the more common types of cervical cancer. It may be difficult to distinguish between a small cell neuroendocrine carcinoma and a small cell nonkeratinizing squamous carcinoma, especially on a small biopsy speci418 Arch Pathol Lab Med—Vol 132, March 2008

men. Similarly, the distinction between a large cell neuroendocrine carcinoma and an undifferentiated carcinoma or a poorly differentiated squamous or adenocarcinoma may be problematic.271 Neuroendocrine markers, such as chromogranin (a specific but relatively insensitive neuroendocrine marker), synaptophysin, PGP9.5, and CD56 assist.271 CD56 is rather nonspecific, with carcinomas of nonneuroendocrine type not uncommonly being positive.272 Cervical small cell neuroendocrine carcinomas, like their pulmonary counterparts, are commonly only focally positive with neuroendocrine markers and some cases are negative, especially on small biopsies.272 A diagnosis of small cell neuroendocrine carcinoma may be made when neuroendocrine markers are negative, if the morphology is typical. p63 may be of value in the distinction between a small cell neuroendocrine and a small cell squamous carcinoma in that most squamous carcinomas exhibit nuclear positivity, whereas neuroendocrine carcinomas are typically negative.273 Cervical adenocarcinomas are usually p63 negative, and this marker may be of use in confirming a poorly differentiated cervical carcinoma to be squamous in type (p63 positive).273 Positive staining with neuroendocrine markers is probably a prerequisite to diagnose a cervical large cell neuroendocrine carcinoma. A high index of suspicion is required to diagnose these neoplasms because some do not have an overt neuroendocrine growth pattern and, as a result, are often misdiagnosed as an undifferentiated carcinoma or a poorly differentiated squamous or glandular carcinoma. Neuroendocrine carcinomas of the cervix are usually p16 positive because of the presence of high-risk HPV.274–276 Recently, TTF-1 nuclear positivity has been described in cases of primary cervical large cell neuroendocrine carcinoma,277 and cervical small cell neuroendocrine carcinomas may also be positive278 TTF-1 positivity is, in fact, not uncommon in extrapulmonary neuroendocrine tumours.278,279 Typical and atypical carcinoids, although extremely rare, are also part of the spectrum of neuroendocrine neoplasms of the cervix and are positive with neuroendocrine markers. Suggested panel: chromogranin, PGP9.5, synaptophysin, CD56, p63. Distinction Between Cervical Microglandular Hyperplasia and Mucinous Adenocarcinoma of the Endometrium This is discussed in the ‘‘Uterine Corpus’’ section. References 1. McCluggage WG. Immunohistochemical and functional biomarkers of value in female genital tract lesions. Int J Gynecol Pathol. 2006;25:101–120. 2. McCluggage WG, Wilkinson N. Metastatic neoplasms involving the ovary: a review with an emphasis on morphological and immunohistochemical features. Histopathology. 2005;47:231–247. 3. McCluggage WG, Young RH. Immunohistochemistry as a diagnostic aid in the evaluation of ovarian tumors. Semin Diagn Pathol. 2005;22:3–32. 4. Lagendijk JH, Mullink H, van Diest PJ, Meijer GA, Meijer CJ. Immunohistochemical differentiation between primary adenocarcinomas of the ovary and ovarian metastases of colonic and breast origin: comparison between a statistical and an intuitive approach. J Clin Pathol. 1999;52:283–290. 5. Netinatsunthorn W, Hanprasertpong J, Dechsukhum C, Leetanaporn R, Geater A. WT1 gene expression as a prognostic marker in advanced serous epithelial ovarian carcinoma: an immunohistochemical study. BMC Cancer. 2006;6:90. 6. Acs G, Pasha T, Zhang PJ. WT1 is differentially expressed in serous, endometrioid, clear cell, and mucinous carcinomas of the peritoneum, fallopian tube, ovary, and endometrium. Int J Gynecol Pathol. 2004;23:110–118. 7. Koutselini HA, Lazaris AC, Thomopoulou G, Papayannopoulou A, Kairi-Vasilatou E. Papillary serous carcinoma of peritoneum: case study and review of the literature on the differential diagnosis of malignant peritoneal tumors. Adv Clin Pathol. 2001;5:99–104. 8. Oishi T, Maruo T, Iwasaki M, Mochizuki M. [Relationship between serum levels and immunohistological tissue levels of CA 125 and CEA in epithelial


ovarian cancers: its implications for tumor cell type specificity]. Nippon Sanka Fujinka Gakkai Zasshi. 1986;38:1595–1604. 9. Lagendijk JH, Mullink H, Van Diest PJ, Meijer GA, Meijer CJ. Tracing the origin of adenocarcinomas with unknown primary using immunohistochemistry: differential diagnosis between colonic and ovarian carcinomas as primary sites. Hum Pathol. 1998;29:491–497. 10. Villena-Heinsen C, Meyberg R, Axt-Fliedner R, Reitnauer K, Reichrath J, Friedrich M. Immunohistochemical analysis of 1,25-dihydroxyvitamin-D3-receptors, estrogen and progesterone receptors and Ki-67 in ovarian carcinoma. Anticancer Res. 2002;22:2261–2267. 11. Dai L, Song Q, Li L, Zhong D, Hui Y. [Expression of cytokeratin 7 and 20 in ovarian metastatic carcinomas]. Zhonghua Bing Li Xue Za Zhi. 2001;30:114– 117. 12. Albarracin CT, Jafri J, Montag AG, Hart J, Kuan SF. Differential expression of MUC2 and MUC5AC mucin genes in primary ovarian and metastatic colonic carcinoma. Hum Pathol. 2000;31:672–677. 13. Groisman GM, Meir A, Sabo E. The value of Cdx2 immunostaining in differentiating primary ovarian carcinomas from colonic carcinomas metastatic to the ovaries. Int J Gynecol Pathol. 2004;23:52–57. 14. Chou YY, Jeng YM, Kao HL, Chen T, Mao TL, Lin MC. Differentiation of ovarian mucinous carcinoma and metastatic colorectal adenocarcinoma by immunostaining with beta-catenin. Histopathology. 2003;43:151–156. 15. Takayama T, Shiozaki H, Shibamoto S, et al. Beta-catenin expression in human cancers. Am J Pathol. 1996;148:39–46. 16. Raspollini MR, Baroni G, Taddei A, Taddei GL. Primary cervical adenocarcinoma with intestinal differentiation and colonic carcinoma metastatic to cervix: an investigation using Cdx-2 and a limited immunohistochemical panel. Arch Pathol Lab Med. 2003;127:1586–1590. 17. Tornillo L, Moch H, Diener PA, Lugli A, Singer G. CDX-2 immunostaining in primary and secondary ovarian carcinomas. J Clin Pathol. 2004;57:641–643. 18. Marquette S, Amant F, Vergote I, Moerman P. Pseudomyxoma peritonei associated with a mucinous ovarian tumor arising from a mature cystic teratoma: a case report. Int J Gynecol Pathol. 2006;25:340–343. 19. Cameron RI, Ashe P, O’Rourke DM, Foster H, McCluggage WG. A panel of immunohistochemical stains assists in the distinction between ovarian and renal clear cell carcinoma. Int J Gynecol Pathol. 2003;22:272–276. 20. Stopyra GA, Warhol MJ, Multhaupt HA. Cytokeratin 20 immunoreactivity in renal oncocytomas. J Histochem Cytochem. 2001;49:919–920. 21. Yang B, Ali SZ, Rosenthal DL. CD10 facilitates the diagnosis of metastatic renal cell carcinoma from primary adrenal cortical neoplasm in adrenal fineneedle aspiration. Diagn Cytopathol. 2002;27:149–152. 22. Mohammed IA, Streutker CJ, Riddell RH. Utilization of cytokeratins 7 and 20 does not differentiate between Barrett’s esophagus and gastric cardiac intestinal metaplasia. Mod Pathol. 2002;15:611–616. 23. Ormsby AH, Goldblum JR, Rice TW, Richter JE, Gramlich TL. The utility of cytokeratin subsets in distinguishing Barrett’s-related oesophageal adenocarcinoma from gastric adenocarcinoma. Histopathology. 2001;38:307–311. 24. Nanashima A, Yamaguchi H, Nakagoe T, et al. High serum concentrations of sialyl Tn antigen in carcinomas of the biliary tract and pancreas. J Hepatobiliary Pancreat Surg. 1999;6:391–395. 25. Nakao A, Ichihara T, Nonami T, et al. Clinicohistopathologic and immunohistochemical studies of intrapancreatic development of carcinoma of the head of the pancreas. Ann Surg. 1989;209:181–187. 26. Nakao A, Ichihara T, Nonami T, et al. [Clinicohistopathological and immunohistochemical studies on intrapancreatic spread of pancreatic carcinoma]. Nippon Geka Gakkai Zasshi. 1987;88:735–742. 27. Takahashi H, Oda T, Hasebe T, et al. Biologically different subgroups of invasive ductal carcinoma of the pancreas: Dpc4 status according to the ratio of intraductal carcinoma components. Clin Cancer Res. 2004;10:3772–3779. 28. Alkushi A, Irving J, Hsu F, et al. Immunoprofile of cervical and endometrial adenocarcinomas using a tissue microarray. Virchows Arch. 2003;442:271–277. 29. Kamoi S, AlJuboury MI, Akin MR, Silverberg SG. Immunohistochemical staining in the distinction between primary endometrial and endocervical adenocarcinomas: another viewpoint. Int J Gynecol Pathol. 2002;21:217–223. 30. Ghandour FA, Attanoos R, Nahar K, Gee JW, Bigrigg A, Ismail SM. Immunocytochemical localization of oestrogen and progesterone receptors in primary adenocarcinoma of the cervix. Histopathology. 1994;24:49–55. 31. Masood S, Rhatigan RM, Wilkinson EW, Barwick KW, Wilson WJ. Expression and prognostic significance of estrogen and progesterone receptors in adenocarcinoma of the uterine cervix: an immunocytochemical study. Cancer. 1993; 72:511–518. 32. Pavlakis K, Messini I, Athanassiadou S, et al. Endocervical glandular lesions: a diagnostic approach combining a semi-quantitative scoring method to the expression of CEA, MIB-1 and p16. Gynecol Oncol. 2006;103:971–976. 33. Horn LC, Lindner K, Szepankiewicz G, et al. p16, p14, p53, and cyclin D1 expression and HPV analysis in small cell carcinomas of the uterine cervix. Int J Gynecol Pathol. 2006;25:182–186. 34. Ishikawa M, Fujii T, Masumoto N, et al. Correlation of p16INK4A overexpression with human papillomavirus infection in cervical adenocarcinomas. Int J Gynecol Pathol. 2003;22:378–385. 35. Negri G, Egarter-Vigl E, Kasal A, Romano F, Haitel A, Mian C. p16INK4a is a useful marker for the diagnosis of adenocarcinoma of the cervix uteri and its precursors: an immunohistochemical study with immunocytochemical correlations. Am J Surg Pathol. 2003;27:187–193. 36. Riethdorf L, Riethdorf S, Lee KR, Cviko A, Loning T, Crum CP. Human


papillomaviruses, expression of p16, and early endocervical glandular neoplasia. Hum Pathol. 2002;33:899–904. 37. Milde-Langosch K, Riethdorf S, Kraus-Poppinghaus A, Riethdorf L, Loning T. Expression of cyclin-dependent kinase inhibitors p16MTS1, p21WAF1, and p27KIP1 in HPV-positive and HPV-negative cervical adenocarcinomas. Virchows Arch. 2001;439:55–61. 38. O’Neill CJ, McBride HA, Connolly LE, Deavers MT, Malpica A, McCluggage WG. High-grade ovarian serous carcinoma exhibits significantly higher p16 expression than low-grade serous carcinoma and serous borderline tumour. Histopathology. 2007;50:773–779. 39. Politi E, Kandaraki C, Apostolopoulou C, Kyritsi T, Koutselini H. Immunocytochemical panel for distinguishing between carcinoma and reactive mesothelial cells in body cavity fluids. Diagn Cytopathol. 2005;32:151–155. 40. Lozano MD, Panizo A, Toledo GR, Sola JJ, Pardo-Mindan J. Immunocytochemistry in the differential diagnosis of serous effusions: a comparative evaluation of eight monoclonal antibodies in Papanicolaou stained smears. Cancer. 2001;93:68–72. 41. Kitazume H, Kitamura K, Mukai K, et al. Cytologic differential diagnosis among reactive mesothelial cells, malignant mesothelioma, and adenocarcinoma: utility of combined E-cadherin and calretinin immunostaining. Cancer. 2000;90: 55–60. 42. Ordonez NG. Role of immunohistochemistry in distinguishing epithelial peritoneal mesotheliomas from peritoneal and ovarian serous carcinomas. Am J Surg Pathol. 1998;22:1203–1214. 43. Doglioni C, Tos AP, Laurino L, et al. Calretinin: a novel immunocytochemical marker for mesothelioma. Am J Surg Pathol. 1996;20:1037–1046. 44. Fetsch PA, Abati A, Hijazi YM. Utility of the antibodies CA 19-9, HBME1, and thrombomodulin in the diagnosis of malignant mesothelioma and adenocarcinoma in cytology. Cancer. 1998;84:101–108. 45. Ordonez NG. Value of thrombomodulin immunostaining in the diagnosis of mesothelioma. Histopathology. 1997;31:25–30. 46. Brown RW, Clark GM, Tandon AK, Allred DC. Multiple-marker immunohistochemical phenotypes distinguishing malignant pleural mesothelioma from pulmonary adenocarcinoma. Hum Pathol. 1993;24:347–354. 47. Ordonez NG. Value of immunohistochemistry in distinguishing peritoneal mesothelioma from serous carcinoma of the ovary and peritoneum: a review and update. Adv Anat Pathol. 2006;13:16–25. 48. Ordonez NG. Value of the MOC-31 monoclonal antibody in differentiating epithelial pleural mesothelioma from lung adenocarcinoma. Hum Pathol. 1998; 29:166–169. 49. Ordonez NG. Value of the Ber-EP4 antibody in differentiating epithelial pleural mesothelioma from adenocarcinoma: the M.D. Anderson experience and a critical review of the literature. Am J Clin Pathol. 1998;109:85–89. 50. Bailey ME, Brown RW, Mody DR, Cagle P, Ramzy I. Ber-EP4 for differentiating adenocarcinoma from reactive and neoplastic mesothelial cells in serous effusions: comparison with carcinoembryonic antigen, B72.3 and Leu-M1. Acta Cytol. 1996;40:1212–1216. 51. Attanoos RL, Goddard H, Thomas ND, Jasani B, Gibbs AR. A comparative immunohistochemical study of malignant mesothelioma and renal cell carcinoma: the diagnostic utility of Leu-M1, Ber EP4, Tamm-Horsfall protein and thrombomodulin. Histopathology. 1995;27:361–366. 52. Tuttle SE, Lucas JG, Bucci DM, Schlom J, Primus J. Distinguishing malignant mesothelioma from pulmonary adenocarcinoma: an immuno-histochemical approach using a panel of monoclonal antibodies. J Surg Oncol. 1990;45:72–78. 53. Ordonez NG. The immunohistochemical diagnosis of mesothelioma: differentiation of mesothelioma and lung adenocarcinoma. Am J Surg Pathol. 1989; 13:276–291. 54. McCluggage WG. Immunoreactivity of juvenile granulosa cell tumours with epithelial membrane antigen. Histopathology. 2005;46:235–236. 55. McCluggage WG, Maxwell P, Sloan JM. Immunohistochemical staining of ovarian granulosa cell tumors with monoclonal antibody against inhibin. Hum Pathol. 1997;28:1034–1038. 56. McCluggage WG. Value of inhibin staining in gynecological pathology. Int J Gynecol Pathol. 2001;20:79–85. 57. McCluggage WG, Maxwell P. Immunohistochemical staining for calretinin is useful in the diagnosis of ovarian sex cord-stromal tumours. Histopathology. 2001;38:403–408. 58. Cathro HP, Stoler MH. The utility of calretinin, inhibin, and WT1 immunohistochemical staining in the differential diagnosis of ovarian tumors. Hum Pathol. 2005;36:195–201. 59. Oliva E, Alvarez T, Young RH. Sertoli cell tumors of the ovary: a clinicopathologic and immunohistochemical study of 54 cases. Am J Surg Pathol. 2005; 29:143–156. 60. Ordi J, Schammel DP, Rasekh L, Tavassoli FA. Sertoliform endometrioid carcinomas of the ovary: a clinicopathologic and immunohistochemical study of 13 cases. Mod Pathol. 1999;12:933–940. 61. Rishi M, Howard LN, Bratthauer GL, Tavassoli FA. Use of monoclonal antibody against human inhibin as a marker for sex cord-stromal tumors of the ovary. Am J Surg Pathol. 1997;21:583–589. 62. Aguirre P, Thor AD, Scully RE. Ovarian endometrioid carcinomas resembling sex cord-stromal tumors: an immunohistochemical study. Int J Gynecol Pathol. 1989;8:364–373. 63. Young RH, Prat J, Scully RE. Ovarian endometrioid carcinomas resembling sex cord-stromal tumors: a clinicopathological analysis of 13 cases. Am J Surg Pathol. 1982;6:513–522.


64. Cheng L. Establishing a germ cell origin for metastatic tumors using OCT4 immunohistochemistry. Cancer. 2004;101:2006–2010. 65. Lau SK, Chang KL. OCT4: a sensitive and specific immunohistochemical marker for metastatic germ cell tumors. Adv Anat Pathol. 2006;13:76–79. 66. Ulbright TM. Germ cell tumors of the gonads: a selective review emphasizing problems in differential diagnosis, newly appreciated, and controversial issues. Mod Pathol. 2005;18(suppl 2):S61–S79. 67. Fabbro D, Di Loreto C, Beltrami CA, Belfiore A, Di Lauro R, Damante G. Expression of thyroid-specific transcription factors TTF-1 and PAX-8 in human thyroid neoplasms. Cancer Res. 1994;54:4744–4749. 68. Kaufmann O, Dietel M. Expression of thyroid transcription factor-1 in pulmonary and extrapulmonary small cell carcinomas and other neuroendocrine carcinomas of various primary sites. Histopathology. 2000;36:415–420. 69. Agoff SN, Lamps LW, Philip AT, et al. Thyroid transcription factor-1 is expressed in extrapulmonary small cell carcinomas but not in other extrapulmonary neuroendocrine tumors. Mod Pathol. 2000;13:238–242. 70. Folpe AL, Gown AM, Lamps LW, et al. Thyroid transcription factor-1: immunohistochemical evaluation in pulmonary neuroendocrine tumors. Mod Pathol. 1999;12:5–8. 71. Szyfelbein WM, Young RH, Scully RE. Cystic struma ovarii: a frequently unrecognized tumor: a report of 20 cases. Am J Surg Pathol. 1994;18:785–788. 72. Cossu-Rocca P, Jones TD, Roth LM, et al. Cytokeratin and CD30 expression in dysgerminoma. Hum Pathol. 2006;37:1015–1021. 73. McCluggage WG. Ovarian neoplasms composed of small round cells: a review. Adv Anat Pathol. 2004;11:288–296. 74. Cheng L, Thomas A, Roth LM, Zheng W, Michael H, Karim FW. OCT4: a novel biomarker for dysgerminoma of the ovary. Am J Surg Pathol. 2004;28:1341– 1346. 75. Wolf HK, Buslei R, Blumcke I, Wiestler OD, Pietsch T. Neural antigens in oligodendrogliomas and dysembryoplastic neuroepithelial tumors. Acta Neuropathol (Berl). 1997;94:436–443. 76. Kairi-Vassilatou E, Kondi-Paphitis A, Antoniou A, Frangou M. Benign cystic mesothelioma of the peritoneum an immunopathological study of three cases. Eur J Gynaecol Oncol. 1999;20:325–326. 77. Fukunaga M. Expression of D2-40 in lymphatic endothelium of normal tissues and in vascular tumours. Histopathology. 2005;46:396–402. 78. Medeiros F, Muto MG, Lee Y, et al. The tubal fimbria is a preferred site for early adenocarcinoma in women with familial ovarian cancer syndrome. Am J Surg Pathol. 2006;30:230–236. 79. Dabbs DJ, Geisinger KR, Norris HT. Intermediate filaments in endometrial and endocervical carcinomas: the diagnostic utility of vimentin patterns. Am J Surg Pathol. 1986;10:568–576. 80. Kudo R, Sasano H, Koizumi M, et al. Immunohistochemical comparison of new monoclonal antibody 1C5 and carcinoembryonic antigen in the differential diagnosis of adenocarcinoma of the uterine cervix. Int J Gynecol Pathol. 1990;9:325–336. 81. Maes G, Fleuren GJ, Bara J, et al. The distribution of mucins, carcinoembryonic antigen, and mucus-associated antigens in endocervical and endometrial adenocarcinomas. Int J Gynecol Pathol. 1988;7:112–122. 82. Dabbs DJ, Sturtz K, Zaino RJ. The immunohistochemical discrimination of endometrioid adenocarcinomas. Hum Pathol. 1996;27:172–177. 83. Ansari-Lari MA, Staebler A, Zaino RJ, et al. Distinction of endocervical and endometrial adenocarcinomas: immunohistochemical p16 expression correlated with human papillomavirus (HPV) DNA detection. Am J Surg Pathol. 2004;28: 160–167. 84. McCluggage WG, Jenkins D. p16 immunoreactivity may assist in the distinction between endometrial and endocervical adenocarcinoma. Int J Gynecol Pathol. 2003;22:231–235. 85. Staebler A, Sherman ME, Zaino RJ, et al. Hormone receptor immunohistochemistry and human papillomavirus in situ hybridization are useful for distinguishing endocervical and endometrial adenocarcinomas. Am J Surg Pathol. 2002;26:998–1006. 86. Pirog EC, Kleter B, Olgac S, et al. Prevalence of human papillomavirus DNA in different histological subtypes of cervical adenocarcinoma. Am J Pathol. 2000;157:1055–1062. 87. Reid-Nicholson M, Iyengar P, Hummer AJ, et al. Immunophenotypic diversity of endometrial adenocarcinomas: implications for differential diagnosis. Mod Pathol. 2006;19:1091–1100. 88. Qiu W, Mittal K. Comparison of morphologic and immunohistochemical features of cervical microglandular hyperplasia with low-grade mucinous adenocarcinoma of the endometrium. Int J Gynecol Pathol. 2003;22:261–265. 89. Zaloudek C, Hayashi GM, Ryan IP, et al. Microglandular adenocarcinoma of the endometrium: a form of mucinous adenocarcinoma that may be confused with microglandular hyperplasia of the cervix. Int J Gynecol Pathol. 1997;16:52– 59. 90. Vang R, Barner R, Wheeler DT, et al. Immunohistochemical staining for Ki-67 and p53 helps distinguish endometrial Arias-Stella reaction from high-grade carcinoma, including clear cell carcinoma. Int J Gynecol Pathol. 2004;23:223– 233. 91. Srodon M, Klein WM, Kurman RJ. CD10 immunostaining does not distinguish endometrial carcinoma invading myometrium from carcinoma involving adenomyosis. Am J Surg Pathol. 2003;27:786–789. 92. Nascimento AF, Hirsch MS, Cviko A, et al. The role of CD10 staining in distinguishing invasive endometrial adenocarcinoma from adenocarcinoma involving adenomyosis. Mod Pathol. 2003;16:22–27.


93. Lax SF, Kendall B, Tashiro H, et al. The frequency of p53, K-ras mutations, and microsatellite instability differs in uterine endometrioid and serous carcinoma: evidence of distinct molecular genetic pathways. Cancer. 2000;88:814–824. 94. Sherman ME, Bur ME, Kurman RJ. p53 in endometrial cancer and its putative precursors: evidence for diverse pathways of tumorigenesis. Hum Pathol. 1995;26:1268–1274. 95. Tashiro H, Isacson C, Levine R, et al. p53 gene mutations are common in uterine serous carcinoma and occur early in their pathogenesis. Am J Pathol. 1997;150:177–185. 96. Kovalev S, Marchenko ND, Gugliotta BG, et al. Loss of p53 function in uterine papillary serous carcinoma. Hum Pathol. 1998;29:613–619. 97. Demopoulos RI, Mesia AF, Mittal K, Vamvakas E. Immunohistochemical comparison of uterine papillary serous and papillary endometrioid carcinoma: clues to pathogenesis. Int J Gynecol Pathol. 1999;18:233–237. 98. Lax SF, Pizer ES, Ronnett BM, et al. Comparison of estrogen and progesterone receptor, Ki-67, and p53 immunoreactivity in uterine endometrioid carcinoma and endometrioid carcinoma with squamous, mucinous, secretory, and ciliated cell differentiation. Hum Pathol. 1998;29:924–931. 99. Lax SF, Pizer ES, Ronnett BM, et al. Clear cell carcinoma of the endometrium is characterized by a distinctive profile of p53, Ki-67, estrogen, and progesterone receptor expression. Hum Pathol. 1998;29:551–558. 100. Soslow RA, Shen PU, Chung MH, et al. Cyclin D1 expression in highgrade endometrial carcinomas—association with histologic subtype. Int J Gynecol Pathol. 2000;19:329–334. 101. Chambers JT, Carcangiu ML, Voynick IM, et al. Immunohistochemical evaluation of estrogen and progesterone receptor content in 183 patients with endometrial carcinoma, part II: correlation between biochemical and immunohistochemical methods and survival. Am J Clin Pathol. 1990;94:255–260. 102. Carcangiu ML, Chambers JT, Voynick IM, et al. Immunohistochemical evaluation of estrogen and progesterone receptor content in 183 patients with endometrial carcinoma, part I: clinical and histologic correlations. Am J Clin Pathol. 1990;94:247–254. 103. Darvishian F, Hummer AJ, Thaler HT, et al. Serous endometrial cancers that mimic endometrioid adenocarcinomas: a clinicopathologic and immunohistochemical study of a group of problematic cases. Am J Surg Pathol. 2004;28: 1568–1578. 104. Burks RT, Kessis TD, Cho KR, Hedrick L. Microsatellite instability in endometrial carcinoma. Oncogene. 1994;9:1163–1166. 105. Risinger JI, Maxwell GL, Chandramouli GV, et al. Gene expression profiling of microsatellite unstable and microsatellite stable endometrial cancers indicates distinct pathways of aberrant signaling. Cancer Res. 2005;65:5031–5037. 106. Black D, Soslow RA, Levine DA, et al. Clinicopathologic significance of defective DNA mismatch repair in endometrial carcinoma. J Clin Oncol. 2006; 24:1745–1753. 107. Peiro G, Diebold J, Lohse P, et al. Microsatellite instability, loss of heterozygosity, and loss of hMLH1 and hMSH2 protein expression in endometrial carcinoma. Hum Pathol. 2002;33:347–354. 108. de Leeuw WJ, Dierssen J, Vasen HF, et al. Prediction of a mismatch repair gene defect by microsatellite instability and immunohistochemical analysis in endometrial tumours from HNPCC patients. J Pathol. 2000;192:328–335. 109. Parc YR, Halling KC, Burgart LJ, et al. Microsatellite instability and hMLH1/hMSH2 expression in young endometrial carcinoma patients: associations with family history and histopathology. Int J Cancer. 2000;86:60–66. 110. Stefansson I, Akslen LA, MacDonald N, et al. Loss of hMSH2 and hMSH6 expression is frequent in sporadic endometrial carcinomas with microsatellite instability: a population-based study. Clin Cancer Res. 2002;8:138–143. 111. Modica I, Soslow RA, Black D, Tornos C, Kauff N, Shia J. Utility of immunohistochemistry in predicting microsatellite instability in endometrial carcinoma. Am J Surg Pathol. 2007;31:744–751. 112. Catasus L, Machin P, Matias-Guiu X, Prat J. Microsatellite instability in endometrial carcinomas: clinicopathologic correlations in a series of 42 cases. Hum Pathol. 1998;29:1160–1164. 113. Basil JB, Goodfellow PJ, Rader JS, et al. Clinical significance of microsatellite instability in endometrial carcinoma. Cancer. 2000;89:1758–1764. 114. Tibiletti MG, Furlan D, Taborelli M, et al. Microsatellite instability in endometrial cancer: relation to histological subtypes. Gynecol Oncol. 1999;73: 247–252. 115. Broaddus RR, Lynch HT, Chen LM, et al. Pathologic features of endometrial carcinoma associated with HNPCC: a comparison with sporadic endometrial carcinoma. Cancer. 2006;106:87–94. 116. van den Bos M, van den Hoven M, Jongejan E, et al. More differences between HNPCC-related and sporadic carcinomas from the endometrium as compared to the colon. Am J Surg Pathol. 2004;28:706–711. 117. Chu PG, Arber DA, Weiss LM, et al. Utility of CD10 in distinguishing between endometrial stromal sarcoma and uterine smooth muscle tumors: an immunohistochemical comparison of 34 cases. Mod Pathol. 2001;14:465–471. 118. Oliva E, Young RH, Amin MB, et al. An immunohistochemical analysis of endometrial stromal and smooth muscle tumors of the uterus—a study of 54 cases emphasizing the importance of using a panel because of overlap in immunoreactivity for individual antibodies. Am J Surg Pathol. 2002;26:403–412. 119. McCluggage WG, Sumathi VP, Maxwell P. CD10 is a sensitive and diagnostically useful immunohistochemical marker of normal endometrial stroma and of endometrial stromal neoplasms. Histopathology. 2001;39:273–278. 120. Nucci MR, O’Connell JT, Huettner PC, et al. h-Caldesmon expression


effectively distinguishes endometrial stromal tumors from uterine smooth muscle tumors. Am J Surg Pathol. 2001;25:455–463. 121. Rush DS, Tan JY, Baergen RN, et al. h-Caldesmon, a novel smooth muscle-specific antibody, distinguishes between cellular leiomyoma and endometrial stromal sarcoma. Am J Surg Pathol. 2001;25:253–258. 122. Sumathi VP, Al-Hussaini M, Connolly LE, et al. Endometrial stromal neoplasms are immunoreactive with WT-1 antibody. Int J Gynecol Pathol. 2004;23: 241–247. 123. Oliva E, Clement PB, Young RH, et al. Mixed endometrial stromal and smooth muscle tumors of the uterus: a clinicopathologic study of 15 cases. Am J Surg Pathol. 1998;22:997–1005. 124. Yilmaz A, Rush DS, Soslow RA. Endometrial stromal sarcomas with unusual histologic features: a report of 24 primary and metastatic tumors emphasizing fibroblastic and smooth muscle differentiation. Am J Surg Pathol. 2002;26: 1142–1150. 125. Oliva E, Young RH, Clement PB, et al. Myxoid and fibrous endometrial stromal tumors of the uterus: a report of 10 cases. Int J Gynecol Pathol. 1999;18: 310–319. 126. Clement PB, Scully RE. Uterine tumors resembling ovarian sex-cord tumors: a clinicopathologic analysis of 14 cases. Am J Clin Pathol. 1976;66:512– 525. 127. Clement PB, Scully RE. Endometrial stromal sarcomas of the uterus with extensive glandular differentiation: a report of three cases that caused problems in differential diagnosis. Int J Gynecol Pathol. 1992;11:163–173. 128. Baker RJ, Hildebrandt RH, Rouse RV, et al. Inhibin and CD99 (MIC2) expression in uterine stromal neoplasms with sex-cord-like elements. Hum Pathol. 1999;30:671–679. 129. Franquemont DW, Frierson HF Jr, Mills SE. An immunohistochemical study of normal endometrial stroma and endometrial stromal neoplasms: evidence for smooth muscle differentiation. Am J Surg Pathol. 1991;15:861–870. 130. Oliva E, Young RH, Clement PB, et al. Cellular benign mesenchymal tumors of the uterus: a comparative morphologic and immunohistochemical analysis of 33 highly cellular leiomyomas and six endometrial stromal nodules, two frequently confused tumors. Am J Surg Pathol. 1995;19:757–768. 131. Bhargava R, Shia J, Hummer AJ, et al. Distinction of endometrial stromal sarcomas from ‘hemangiopericytomatous’ tumors using a panel of immunohistochemical stains. Mod Pathol. 2005;18:40–47. 132. Farhood AI, Abrams J. Immunohistochemistry of endometrial stromal sarcoma. Hum Pathol. 1991;22:224–230. 133. Zhai YL, Kobayashi Y, Mori A, et al. Expression of steroid receptors, Ki67, and p53 in uterine leiomyosarcomas. Int J Gynecol Pathol. 1999;18:20–28. 134. Nordal RR, Kristensen GB, Stenwig AE, et al. Immunohistochemical analysis of p53 protein in uterine sarcomas. Gynecol Oncol. 1998;70:45–48. 135. Blom R, Guerrieri C, Stal O, et al. Leiomyosarcoma of the uterus: a clinicopathologic, DNA flow cytometric, p53, and mdm-2 analysis of 49 cases. Gynecol Oncol. 1998;68:54–61. 136. Leitao MM, Soslow RA, Nonaka D, et al. Tissue microarray immunohistochemical expression of estrogen, progesterone, and androgen receptors in uterine leiomyomata and leiomyosarcoma. Cancer. 2004;101:1455–1462. 137. Mittal K, Demopoulos RI. MIB-1 (Ki-67), p53, estrogen receptor, and progesterone receptor expression in uterine smooth muscle tumors. Hum Pathol. 2001;32:984–987. 138. Rizeq MN, Van de Rijn M, Hendrickson MR, et al. A comparative immunohistochemical study of uterine smooth muscle neoplasms with emphasis on the epithelioid variant. Hum Pathol. 1994;25:671–677. 139. Vang R, Kempson RL. Perivascular epithelioid cell tumor (‘PEComa’) of the uterus: a subset of HMB-45-positive epithelioid mesenchymal neoplasms with an uncertain relationship to pure smooth muscle tumors. Am J Surg Pathol. 2002; 26:1–13. 140. Silva EG, Deavers MT, Bodurka DC, et al. Uterine epithelioid leiomyosarcomas with clear cells: reactivity with HMB-45 and the concept of PEComa. Am J Surg Pathol. 2004;28:244–249. 141. Folpe AL, Mentzel T, Lehr HA, et al. Perivascular epithelioid cell neoplasms of soft tissue and gynecologic origin: a clinicopathologic study of 26 cases and review of the literature. Am J Surg Pathol. 2005;29:1558–1575. 142. Hurrell DP, McCluggage WG. Uterine leiomyosarcoma with HMB45⫹ clear cell areas: report of two cases. Histopathology. 2005;47:540–542. 143. Oliva E, Wang WL, Branton P, et al. Expression of melanocytic (‘‘PEComa’’) markers in smooth muscle tumors of the uterus: an immunohistochemical analysis of 86 cases [abstract]. Mod Pathol. 2006;19:191A. Abstract 884. 144. Klein WM, Kurman RJ. Lack of expression of c-kit protein (CD117) in mesenchymal tumors of the uterus and ovary. Int J Gynecol Pathol. 2003;22:181– 184. 145. Winter WE, III, Seidman JD, Krivak TC, et al. Clinicopathological analysis of c-kit expression in carcinosarcomas and leiomyosarcomas of the uterine corpus. Gynecol Oncol. 2003;91:3–8. 146. Wang L, Felix JC, Lee JL, et al. The proto-oncogene c-kit is expressed in leiomyosarcomas of the uterus. Gynecol Oncol. 2003;90:402–406. 147. Rushing RS, Shajahan S, Chendil D, et al. Uterine sarcomas express KIT protein but lack mutation(s) in exon 11 or 17 of c-KIT. Gynecol Oncol. 2003;91: 9–14. 148. Irving JA, Lerwill MF, Young RH. Gastrointestinal stromal tumors metastatic to the ovary: a report of five cases. Am J Surg Pathol. 2005;29:920–926. 149. Altrabulsi B, Malpica A, Deavers MT, et al. Undifferentiated carcinoma of the endometrium. Am J Surg Pathol. 2005;29:1316–1321.


150. Ferguson SE, Tornos C, Barakat RR, Soslow RA. Prognostic features of surgical stage I uterine carcinosarcoma [abstract]. Mod Pathol. 2006;19:178A. Abstract 822. 151. Cessna MH, Zhou H, Perkins SL, et al. Are myogenin and myoD1 expression specific for rhabdomyosarcoma? A study of 150 cases, with emphasis on spindle cell mimics. Am J Surg Pathol. 2001;25:1150–1157. 152. Cui S, Hano H, Harada T, et al. Evaluation of new monoclonal antiMyoD1 and anti-myogenin antibodies for the diagnosis of rhabdomyosarcoma. Pathol Int. 1999;49:62–68. 153. Kumar S, Perlman E, Harris CA, et al. Myogenin is a specific marker for rhabdomyosarcoma: an immunohistochemical study in paraffin-embedded tissues. Mod Pathol. 2000;13:988–993. 154. Fukunaga M. Immunohistochemical characterization of p57(KIP2) expression in early hydatidiform moles. Hum Pathol. 2002;33:1188–1192. 155. Fisher RA, Hodges MD, Rees HC, et al. The maternally transcribed gene p57(KIP2) (CDNK1C) is abnormally expressed in both androgenetic and biparental complete hydatidiform moles. Hum Mol Genet. 2002;11:3267–3272. 156. Genest DR, Dorfman DM, Castrillon DH. Ploidy and imprinting in hydatidiform moles: complementary use of flow cytometry and immunohistochemistry of the imprinted gene product p57KIP2 to assist molar classification. J Reprod Med. 2002;47:342–346. 157. Castrillon DH, Sun DQ, Weremowicz S, et al. Discrimination of complete hydatidiform mole from its mimics by immunohistochemistry of the paternally imprinted gene product p57KIP2. Am J Surg Pathol. 2001;25:1225–1230. 158. Popiolek DA, Yee H, Mittal K, et al. Multiplex short tandem repeat DNA analysis confirms the accuracy of p57(KIP2) immunostaining in the diagnosis of complete hydatidiform mole. Hum Pathol. 2006;37:1426–1434. 159. Mao TL, Seidman JD, Kurman RJ, Shih IM. Cyclin E and p16 immunoreactivity in epithelioid trophoblastic tumor—an aid in differential diagnosis. Am J Surg Pathol. 2006;30:1105–1110. 160. Isacson C, Kessis TD, Hedrick L, et al. Both cell proliferation and apoptosis increase with lesion grade in cervical neoplasia but do not correlate with human papillomavirus type. Cancer Res. 1996;56:669–674. 161. Shih IM, Seidman JD, Kurman RJ. Placental site nodule and characterization of distinctive types of intermediate trophoblast. Hum Pathol. 1999;30:687– 694. 162. Shih IM, Kurman RJ. Ki-67 labeling index in the differential diagnosis of exaggerated placental site, placental site trophoblastic tumor, and choriocarcinoma: a double immunohistochemical staining technique using Ki-67 and MelCAM antibodies. Hum Pathol. 1998;29:27–33. 163. Shih IM, Kurman RJ. p63 expression is useful in the distinction of epithelioid trophoblastic and placental site trophoblastic tumors by profiling trophoblastic subpopulations. Am J Surg Pathol. 2004;28:1177–1183. 164. Hameed A, Miller DS, Muller CY, et al. Frequent expression of betahuman chorionic gonadotropin (beta-hCG) in squamous cell carcinoma of the cervix. Int J Gynecol Pathol. 1999;18:381–386. 165. Bacchi CE, Coelho KI, Goldberg J. Expression of beta-human chorionic gonadotropin (beta-hCG) in non-trophoblastic elements of transitional cell carcinoma of the bladder: possible relationship with the prognosis. Rev Paul Med. 1993;111:412–416. 166. McCluggage WG. A review and update of morphologically bland vulvovaginal mesenchymal lesions. Int J Gynecol Pathol. 2005;24:26–38. 167. Nucci MR, Fletcher CD. Vulvovaginal soft tissue tumours: update and review. Histopathology. 2000;36:97–108. 168. Nielsen GP, Young RH. Mesenchymal tumors and tumor-like lesions of the female genital tract: a selective review with emphasis on recently described entities. Int J Gynecol Pathol. 2001;20:105–127. 169. Steeper TA, Rosai J. Aggressive angiomyxoma of the female pelvis and perineum: report of nine cases of a distinctive type of gynecologic soft-tissue neoplasm. Am J Surg Pathol. 1983;7:463–475. 170. Begin LR, Clement PB, Kirk ME, et al. Aggressive angiomyxoma of pelvic soft parts: a clinicopathologic study of nine cases. Hum Pathol. 1985;16:621– 628. 171. Fletcher CDM, Tsang WY, Fisher C, et al. Angiomyofibroblastoma of the vulva: a benign neoplasm distinct from aggressive angiomyxoma. Am J Surg Pathol. 1992;16:373–382. 172. Fetsch JF, Laskin WB, Lefkowitz M, et al. Aggressive angiomyxoma: a clinicopathologic study of 29 female patients. Cancer. 1996;78:79–90. 173. Fukunaga M, Nomura K, Matsumoto K, et al. Vulval angiomyofibroblastoma: clinicopathologic analysis of six cases. Am J Clin Pathol. 1997;107:45–51. 174. Hisaoka M, Kouho H, Aoki T, et al. Angiomyofibroblastoma of the vulva: a clinicopathologic study of seven cases. Pathol Int. 1995;45:487–492. 175. Nielsen GP, Rosenberg AE, Young RH, et al. Angiomyofibroblastoma of the vulva and vagina. Mod Pathol. 1996;9:284–291. 176. Canales BK, Weiland D, Hoffman N, et al. Angiomyofibroblastoma-like tumors (cellular angiofibroma). Int J Urol. 2006;13:177–179. 177. Fletcher CD. Recent developments in soft tissue tumors. Verh Dtsch Ges Pathol. 1998;82:33–46. 178. McCluggage WG, White RG. Angiomyofibroblastoma of the vagina. J Clin Pathol. 2000;53:803. 179. Laskin WB, Fetsch JF, Tavassoli FA. Angiomyofibroblastoma of the female genital tract: analysis of 17 cases including a lipomatous variant. Hum Pathol. 1997;28:1046–1055. 180. Nucci MR, Granter SR, Fletcher CD. Cellular angiofibroma: a benign


neoplasm distinct from angiomyofibroblastoma and spindle cell lipoma. Am J Surg Pathol. 1997;21:636–644. 181. McCluggage WG, Ganesan R, Hirschowitz L, et al. Cellular angiofibroma and related fibromatous lesions of the vulva: report of a series with a morphological spectrum wider than previously described. Histopathology. 2005;45:360– 368. 182. Iwasa Y, Fletcher CD. Cellular angiofibroma: a clinicopathologic and immunohistochemical analysis of 51 cases. Am J Surg Pathol. 2004;28:1426–1435. 183. Miettinen M, Wahlstrom T, Vesterinen E, et al. Vaginal polyps with pseudosarcomatous features: a clinicopathologic study of seven cases. Cancer. 1983; 51:1148–1151. 184. Ostor AG, Fortune DW, Riley CB. Fibroepithelial polyps with atypical stromal cells (pseudosarcoma botryoides) of vulva and vagina: a report of 13 cases. Int J Gynecol Pathol. 1988;7:351–360. 185. Nucci MR, Young RH, Fletcher CDM. Cellular pseudosarcomatous fibroepithelial stromal polyps of the lower female genital tract: an underrecognized lesion often misdiagnosed as sarcoma. Am J Surg Pathol. 2000;24:231–240. 186. Nielsen GP, Rosenberg AE, Koerner FC, et al. Smooth-muscle tumors of the vulva: a clinicopathologic study of 25 cases and review of the literature. Am J Surg Pathol. 1996;20:779–793. 187. Tavassoli FA, Norris HJ. Smooth muscle tumors of the vulva. Obstet Gynecol. 1979;53:213–217. 188. Laskin WB, Fetsch JF, Tavassoli FA. Superficial cervicovaginal myofibroblastoma: fourteen cases of a distinctive mesenchymal tumor arising from the specialized subepithelial stroma of the lower female genital tract. Hum Pathol. 2001;32:715–725. 189. Ganesan R, McCluggage WG, Hirschowitz L, et al. Superficial myofibroblastoma of the lower female genital tract: report of a series, including tumours with a vulval location. Histopathology. 2005;46:137–143. 190. Stewart CJ, Amanuel B, Brennan BA, et al. Superficial cervicovaginal myofibroblastoma: a report of five cases. Pathology. 2005;37:144–148. 191. McCluggage WG, Patterson A, Maxwell P. Aggressive angiomyxoma of pelvic parts exhibits oestrogen and progesterone receptor positivity. J Clin Pathol. 2000;53:603–605. 192. Fine BA, Munoz AK, Litz GE, et al. Primary medical management of recurrent aggressive angiomyxoma of the vulva with a gonadotropin-releasing hormone agonist. Gynecol Oncol. 2001;81:120–122. 193. McCluggage WG, Jamieson T, Dobbs SP, et al. Aggressive angiomyxoma of the vulva: response to gonadotropin-releasing hormone agonist therapy. Gynecol Oncol. 2006;100:623–625. 194. Nucci MR, Weremowicz S, Neskey DM, et al. Chromosomal translocation t(8;12) induced aberrant HMGIC expression in aggressive angiomyxoma of the vulva. Genes Chromosomes Cancer. 2001;32:172–176. 195. Lam LA, Corless CL, Goldblum JR, et al. Extragastrointestinal stromal tumors presenting as vulvovaginal/rectovaginal septal masses: a diagnostic pitfall. Int J Gynecol Pathol. 2006;25:288–292. 196. Logani S, Cu D, Quint WGV, Ellenson LH, Pirog EC. Low-grade vulvar and vaginal intraepithelial neoplasia: correlation of histologic features with human papillomavirus DNA detection and MIB1 immunostaining. Mod Pathol. 2003;16:735–741. 197. Pirog EC, Chen YT, Isacson C. MIB1 immunostaining is a beneficial adjunct test for accurate diagnosis of vulvar condyloma accuminatum. Am J Surg Pathol. 2000;24:1393–1399. 198. Santos M, Montagut C, Mellado B, et al. Immunohistochemical staining for p16 and p53 in premalignant and malignant epithelial lesions of the vulva. Int J Gynecol Pathol. 2004;23:206–214. 199. Ruhul-Quddus M, Xu C, Steinhoff MM, et al. Simplex (differentiated) type VIN: absence of p16INK4 supports its weak association with HPV and its probable precursor role in non-HPV related vulvar squamous cancers. Histopathology. 2005;46:718–720. 200. Zang B, Hart WR. Vulvular intraepithelial neoplasia of the simplex (differentiated) type: a clinicopathologic study including analysis of HPV and p53 expression. Am J Surg Pathol. 2000;24:429–441. 201. Liegl B, Regaueur S. p53 immunostaining in lichen sclerosus is related to ischaemic stress and is not a marker of differentiated vulvar intraepithelial neoplasia (d-VIN). Histopathology. 2006;48:268–274. 202. Goldblum JR, Hart WR. Perianal Paget’s disease—a histologic and immunohistochemical study of 11 cases with and without associated rectal adenocarcinoma. Am J Surg Pathol. 1998;2:170–171. 203. Goldblum JR, Hart WR. Vulvar Paget’s diseases; a clinicopathologic and immunohistochemical study of 19 cases. Am J Surg Pathol. 1997;21:1178–1187. 204. Liegl B, Horn LC, Moinfar F. Androgen receptors are frequently expressed in mammary and extramammary Paget’s disease. Mod Pathol. 2005;18:1283– 1288. 205. Brummer O, Stegner HE, Buhmer G, et al. HER-2/neu expression in Paget disease of the vulva and the female genital tract. Gynecol Oncol. 2004;95:336– 340. 206. Raju RR, Goldblum JR, Hart WR. Pagetoid squamous cell carcinoma in situ (Pagetoid Bowen’s disease) of the external genitalia. Int J Gynecol Pathol. 2003;22:127–135. 207. Zeng HA, Cartun R, Ricci A Jr. Potential diagnostic utility of CDX-2 immunophenotyping in extramammary Paget’s disease. Appl Immunohistochem Mol Morphol. 2005;13:342–346. 208. Brown HM, Wilkinson EJ. Uroplakin-III to distinguish primary vulvar Pag-


et disease from Paget disease secondary to urothelial carcinoma. Hum Pathol 2002;33:545–548. 209. Kuan S-F, Montag AG, Hart J, Krausz T, Recant W. Differential expression of mucin genes in mammary and extramammary Paget’s disease. Am J Surg Pathol. 2001;25:1469–1477. 210. Zhang C, Zhang P, Sung J, Lawrence WD. Overexpression of p53 is correlated with stromal invasion in extramammary Paget’s disease of the vulva. Hum Pathol. 2003;34:880–885. 211. Regaueur S. Extramammary Paget’s disease—proliferation of adnexal origin? Histopathology. 2006;48:723–729. 212. Mittal K. Utility of MIB1 in evaluating cauterised cervical cone biopsy margins. Int J Gynecol Pathol. 1999;18:211–214. 213. McCluggage WG, Tang L, Maxwell P, Bharucha H. Monoclonal antibody MIB1 in the assessment of cervical squamous intraepithelial lesions. Int J Gynecol Pathol. 1996;15:131–136. 214. Mittal K, Mesia A, Demopoulos RL. MIB1 expression is useful in distinguishing dysplasia from atrophy in elderly women. Int J Gynecol Pathol. 1999; 18:122–124. 215. Pirog EC, Baergen RN, Soslow RA, et al. Diagnostic accuracy of cervical low-grade squamous intraepithelial lesions is improved with MIB1 immunostaining. Am J Surg Pathol. 2002;26:70–75. 216. Kruse A-J, Baak JPA, Helliesen T, et al. Evaluation of MIB-1 positive cell clusters as a diagnostic marker for cervical intraepithelial neoplasia. Am J Surg Pathol. 2002;26:1501–1507. 217. Sano T, Oyama T, Kashiwabara K, et al. Expression status of p16 protein is associated with human papillomavirus oncogenic potential in cervical and genital lesions. Am J Pathol. 1998;153:1741–1748. 218. Klaes R, Friedrich T, Spitkovsky D, et al. Overexpression of p16 INK4A as a specific marker for dysplastic and neoplastic epithelial cells of the cervix uteri. Int J Cancer. 2001;92:276–284. 219. Keating JT, Cviko A, Reithdorf S, et al. Ki-67, cyclin E and p16 are complimentary surrogate biomarkers for human papillomavirus-related cervical neoplasia. Am J Surg Pathol. 2001;25:884–891. 220. Milde-Langosch K, Reithdorf S, Kraws-Poppinghaus A. Expression of cyclin-dependent kinase inhibitors p16, p21 and p27 in HPV-positive and HPVnegative cervical adenocarcinomas. Virchows Arch. 2001;439:55–61. 221. O’Neill CJ, McCluggage WG. p16 expression in the female genital tract and its value in diagnosis. Adv Anat Pathol. 2006;13:8–15. 222. Klaes R, Friedrich T, Spitkovsky D, et al. Overexpression of p16 (INK4A) as a specific marker for dysplastic and neoplastic epithelial cells of the cervix uteri. Int J Cancer. 2002;92:276–284. 223. Klaes R, Benner A, Freidrich T, et al. p16 (INK4A) immunohistochemistry improves interobserver agreement in the diagnosis of cervical intraepithelial neoplasia. Am J Surg Pathol. 2002;26:1387–1399. 224. Agoff SN, Lin P, Morihara J, Mao C, Kiviat NB, Koutsky LA. p16 INK4A expression correlates with degree of cervical neoplasia: a comparison with Ki-67 expression and detection of high-risk HPV types. Mod Pathol. 2003;16:665–673. 225. Benevolo M, Mottolese M, Marandino F, et al. Immunohistochemical expression of p16 INK4A is predictive of HR-HPV infection in cervical low-grade lesions. Mod Pathol. 2006;19:384–391. 226. Tavassoli FA, Devilee P, eds. Pathology and Genetics of Tumours of the Breast and Female Genital Organs. Lyon, France: IARC Press; 2003. World Health Organization Classification of Tumours. 227. McCluggage WG, Maxwell P, McBride HA, Hamilton PW, Bharucha H. Monoclonal antibodies Ki-67 and MIB1 in the distinction of tuboendometrial metaplasia from endocervical adenocarcinoma and adenocarcinoma in situ in formalin fixed material. Int J Gynecol Pathol. 1995;14:209–216. 228. Lee KR, Sun D, Crum CP. Endocervical intraepithelial glandular atypia (dysplasia): a histopathologic, human papillomavirus, and MIB-1 analysis of 25 cases. Hum Pathol. 2000;31:656–664. 229. Pirog EC, Isacson C, Szabolcs MJ, et al. Proliferative activity of benign and neoplastic endocervical epithelium and correlation with HPV DNA detection. Int J Gynecol Pathol. 2002;21:22–26. 230. Cameron RI, Maxwell P, Jenkins D, McCluggage WG. Immunohistochemical staining with MIB-1, bcl2 and p16 assists in the distinction of cervical glandular intraepithelial neoplasia from tubo-endometrial metaplasia, endometriosis and microglandular hyperplasia. Histopathology. 2002;41:313–321. 231. McCluggage WG, Maxwell P. Bcl-2 and p21 staining of cervical tuboendometrial metaplasia. Histopathology. 2002;40:107. 232. Negri G, Egarter-Vigi E, Kasal A, et al. p16 (INK4a) is a useful marker for the diagnosis of adenocarcinoma of the cervix uteri and its precursors. Am J Surg Pathol. 2003;27:187–193. 233. Riethdorf L, Riethdorf S, Lee KR, Cviko A, Loning T, Crum CP. Human papillomaviruses, expression of p16 INK4A, and early endocervical glandular neoplasia. Hum Pathol. 2002;33:899–904. 234. Ishikawa M, Fujii T, Nasumoto N, et al. Correlation of p16 INK4A overexpression with human papillomavirus infection in cervical adenocarcinomas. Int J Gynecol Pathol. 2003;22:378–385. 235. Marques T, Andrade LA, Vassalo J. Endocervical tubal metaplasia and adenocarcinoma in situ: role of immunohistochemistry for carcinoembryonic antigen and vimentin in differential diagnosis. Histopathology. 1996;28:549–550. 236. Cina SJ, Richardson MS, Austin RM, Kurman RJ. Immunohistochemical staining for Ki-67 antigen, carcinoembryonic antigen, and p53 in the differential diagnosis of glandular lesions of the cervix. Mod Pathol. 1997;10:176–180.


237. Wells M, Brown LJR. Symposium part IV: investigative approaches to endocervical pathology. Int J Gynecol Pathol. 2002;21:360–367. 238. Riethdorf L, O’Connell JT, Riethdorf S, Cviko A, Crum CP. Differential expression of MUC2 and MUC5AC in benign and malignant glandular lesions of the cervix. Virchows Arch. 2000;437:365–371. 239. Griffin NR, Wells M. Semi-quantitative immunohistochemical studies of blood group antigen A, B, H, Lea, Leb structures and Ii backbone chains in the normal human cervix and in cervical adenocarcinoma. Histochem J. 1993;25: 228–241. 240. Griffen NR, Wells M. Characterization of complex carbohydrates in cervical glandular intraepithelial neoplasia and invasive adenocarcinoma. Int J Gynecol Pathol. 1994;13:319–329. 241. Ibrahim E, Blackett AD, Tidy JA, Wells M. CD44 is a marker of endocervical neoplasia. Int J Gynecol Pathol. 1999;18:101–108. 242. McCluggage WG, Oliva E, Herrington CS, McBride H, Young RH. CD10 and calretinin staining of endocervical glandular lesions, endocervical stroma and endometrioid adenocarcinoma of the uterine corpus: CD10 positivity is characteristic of, but not specific for, mesonephric lesions and is not specific for endometrioid stroma. Histopathology. 2003;43:144–150. 243. Ordi J, Nogales FF, Palacia A, et al. Mesonephric adenocarcinoma of the uterine corpus: CD10 expression as evidence of mesonephric differentiation. Am J Surg Pathol. 2001;25:1540–1545. 244. Ordi J, Romagosa C, Tavassoli FA, et al. CD10 expression in epithelial tissues and tumors of the gynecologic tract; a useful marker in the diagnosis of mesonephric, trophoblastic and clear cell tumors. Am J Surg Pathol. 2003;27: 178–186. 245. McCluggage WG, Sumathi VP, Maxwell P. CD10 is a sensitive and diagnostically useful marker of normal endometrial stroma and of endometrial stromal neoplasms. Histopathology. 2001;39:273–278. 246. Silver SA, Devouassoux-Shisheboran M, Mezetti TP, Tavassoli FA. Mesonephric adenocarcinomas of the uterine cervix: a study of 11 cases with immunohistochemical findings. Am J Surg Pathol. 2001;25:379–387. 247. Truskinovsky AM, Stelow EB, Jessurun J, et al. Staining for p16 of cervical mesonephric remnants and hyperplasia: a potential diagnostic pitfall. Mod Pathol. 2006;19:925(A). 248. Utsugi K, Hira Y, Takeshima N, Akiyama F, Sakurai S, Hasumi K. Utility of the monoclonal antibody HIK1083 in the diagnosis of adenoma malignum of the uterine cervix. Gynecol Oncol. 1999;75:345–348. 249. Mikami Y, Kiyokawa T, Hata S, et al. Gastrointestinal immunophenotype in adenocarcinomas of the uterine cervix and related glandular lesions: a possible link between lobular endocervical glandular hyperplasia/pyloric gland metaplasia and adenoma malignum. Mod Pathol. 2004;17:962–972. 250. Ichimura T, Koizumi T, Tateiwa H, et al. Immunohistochemical expression of gastric mucin and p53 in minimal deviation adenocarcinoma of the uterine cervix. Int J Gynecol Pathol. 2001;20:220–226. 251. Steeper TA, Wick ME. Minimal deviation adenocarcinoma of the uterine cervix (‘‘adenoma malignum’’): an immunohistochemical comparison with microglandular hyperplasia and conventional endocervical adenocarcinoma. Cancer. 1986;58:1131–1138. 252. Gilks CB, Young RH, Aguirre P, et al. Adenoma malignum (minimal deviation adenocarcinoma) of the uterine cervix: a clinicopathological and immunohistochemical analysis of 26 cases. Am J Surg Pathol. 1989;13:717–729. 253. Mikami Y, Kiyokawa T, Hata S, et al. Gastrointestinal immunophenotype in adenocarcinomas of the uterine cervix and related glandular lesions: a possible link between lobular endocervical glandular hyperplasia/pyloric gland metaplasia and ‘‘adenoma malignum.’’ Mod Pathol. 2004;17:967–972. 254. Mikami Y, Hata S, Melamed J, Fujiwara K, Manabe T. Lobular endocervical glandular hyperplasia is a metaplastic process with a pyloric gland phenotype. Histopathology. 2001;39:364–372. 255. Kondo T, Hashi A, Murata S, et al. Endocervical adenocarcinomas associated with lobular endocervical glandular hyperplasia: a report of four cases with histochemical and immunohistochemical analysis. Mod Pathol. 2005;15:1199– 1210. 256. Hashi A, Xu JY, Kondo T, et al. p16INK4A overexpression independent of human papillomavirus infection in lobular endocervical glandular hyperplasia. Int J Gynecol Pathol. 2006;25:187–194. 257. Mikami Y, Kiyokawa T, Moriya T, et al. Immunophenotypic alteration of the stromal component in minimal deviation adenocarcinoma (‘‘adenoma malignum’’) and endocervical glandular hyperplasia: a study using oestrogen receptor and alpha-smooth muscle actin double immunostaining. Histopathology. 2005; 46:130–136. 258. Nucci MR, Ferry JA, Young RH. Ectopic prostatic tissue in the uterine


cervix: a report of four cases and review of ectopic prostatic tissue. Am J Surg Pathol. 2000;24:1224–1230. 259. McCluggage WG, Ganesan R, Hirschowitz L, et al. Ectopic prostatic tissue in the uterine cervix and vagina: report of a series with a detailed immunohistochemical analysis. Am J Surg Pathol. 2006;30:209–215. 260. Staebler A, Sherman ME, Zaino RJ, et al. Hormone receptor immunohistochemistry and human papillomavirus in situ hybridisation are useful for distinguishing endocervical and endometrial adenocarcinomas. Am J Surg Pathol. 2002;26:998–1006. 261. Castrillon DH, Lee KR, Nucci MR. Distinction between endometrial and endocervical adenocarcinoma: an immunohistochemical study. Int J Gynecol Pathol. 2002;21:4–10. 262. McCluggage WG, Sumathi VP, McBride HA, et al. A panel of immunohistochemical stains, including carcinoembryonic antigen, vimentin and estrogen receptor aids the distinction between primary endometrial and endocervical adenocarcinomas. Int J Gynecol Pathol. 2002;21:11–15. 263. Zaino RJ. The fruits of our labours: distinguishing endometrial from endocervical adenocarcinoma. Int J Gynecol Pathol. 2002;21:1–3. 264. McCluggage WG, Jenkins D. Immunohistochemical staining with p16 may assist in the distinction between endometrial and endocervical adenocarcinoma. Int J Gynecol Pathol. 2003;22:231–235. 265. Schorge JO, Lea JS, Elias KJ, et al. P16 as a molecular biomarker of cervical adenocarcinoma. Am J Obstet Gynecol. 2004;190:668–673. 266. Ansari-Lari MA, Staebler A, Zaino RJ, Shah KV, Ronnett BM. Distinction of endocervical and endometrial adenocarcinomas: immunohistochemical p16 expression correlated with human papillomavirus (HPV) DNA detection. Am J Surg Pathol. 2004;28:160–167. 267. Armes JE, Lourie R, de Silva M, et al. Abnormalities of the RB1 pathway in ovarian serous papillary carcinoma as determined by overexpression of the p16 (INK4A) protein. Int J Gynecol Pathol. 2005;24:363–368. 268. O’Neill CJ, McBride HA, Connolly LE, Deavers MT, Malpica A, McCluggage WG. High-grade ovarian serous carcinoma exhibits significantly higher p16 expression than low-grade serous carcinoma and serous borderline tumour. Histopathology. 2007;50:773–779. 269. Tambouret R, Clement PB, Young RH. Endometrial endometrioid adenocarcinoma with a deceptive pattern of spread to the uterine cervix: a manifestation of stage IIb endometrial carcinoma liable to be misinterpreted as an independent carcinoma or a benign lesion. Am J Surg Pathol. 2003;27:1080–1088. 270. Kamoi S, Al Juboury ML, Akin MR, et al. Immunohistochemical staining in the distinction between endometrial and endocervical adenocarcinomas: another viewpoint. Int J Gynecol Pathol. 2002;21:217–223. 271. Gilks CB, Young RH, Gersell DJ, Clement PB. Large cell neuroendocrine carcinoma of the uterine cervix: a clinicopathologic study of 12 cases. Am J Surg Pathol. 1997;21:905–914. 272. Albores-Saavedra J, Latif S, Carrick KS, et al. CD56 immunoreactivity in small cell carcinoma of the uterine cervix. Int J Gynecol Pathol. 2005;24:113– 117. 273. Wang TY, Chen BF, Yang YC, et al. Histologic and immunophenotypic classification of cervical carcinomas by expression of the p53 homologue p63: a study of 250 cases. Hum Pathol. 2001;32:479–86. 274. Horn L-C, Lindner K, Szepankiewicz GTA, et al. p16, p14, p53, and cyclin D1 expression and HPV analysis in small cell carcinomas of the uterine cervix. Int J Gynecol Pathol. 2006;25:182–186. 275. Wang HL, Lu D. Detection of human papillomavirus DNA and expression of p16, Rb, and p53 proteins in small cell carcinomas of the uterine cervix. Am J Surg Pathol. 2004;28:901–908. 276. Masumoto N, Fujii T, Ishikawa M, et al. p16INK4A overexpression and human papillomavirus infection in small cell carcinoma of the uterine cervix. Hum Pathol. 2003;34:778–783. 277. McCluggage WG, Sargent A, Bailey A, Wilson GE. Large cell neuroendocrine carcinoma of the uterine cervix exhibiting TTF1 immunoreactivity. Histopathology. 2007;51:405–407. 278. Agoff SN, Lamp TW, Philip AT, et al. Thyroid transcription factor-1 is expressed in extrapulmonary small cell carcinomas but not in other extrapulmonary neuroendocrine tumors. Mod Pathol. 2000;13:238–242. 279. Jones TD, Kernek KM, Yang XJ, et al. Thyroid transcription factor 1 expression in small cell carcinoma of the urinary bladder: an immunohistochemical profile of 44 cases. Hum Pathol. 2005;36:718–723. 280. Soslow RA, Isacson C, Zaloudek C. Immunohistology of the female genital tract. In: Dabbs D, ed. Diagnostic Immunohistochemistry. 2nd ed. Philadelphia, Pa: Churchill Livingstone; 2006:637–698. 281. Darvishian F, Hummer AJ, Thaler H, et al. Serous endometrial cancers that mimic endometrioid adenocarcinomas: a clinicopathologic and immunohistochemical study of a group of problematic cases. Am J Surg Pathol. 2004;28: 1568–1578.


Application of Immunohistochemistry to Gynecologic Pathology

Application of Immunohistochemistry to Gynecologic Pathology

Suggest Documents

Gynecologic and Breast Pathology

Application of Immunohistochemistry to Cytology - Archives of ...

Application of Immunohistochemistry to Thyroid Neoplasms

Pathology and immunohistochemistry of papillomavirus-associated ...

Pathology and Immunohistochemistry of Callitrichid Hepatitis ... - NCBI

Immunohistochemistry, ultrastructure and pathology ... - Inter Research

Immunohistochemistry in diagnostic veterinary pathology: a ... - SciELO

Application of Immunohistochemistry in the Diagnosis ...

The use of immunohistochemistry in an oral pathology laboratory

Immunohistochemistry (IHC) an Application Guide

Immunohistochemistry (IHC) an Application Guide

Inability of immunohistochemistry to predict clinical

CAP Standardized Pathology Fellowship Application

Development of Immunohistochemistry Assays to Assess GALNT14 ...

Remote Detection of Crop Stress: Application to Plant Pathology

immunohistochemistry

Development of Immunohistochemistry Assays to Assess GALNT14 ...

Immunohistochemistry of Melanocytic Proliferations

TECHNICAL IMMUNOHISTOCHEMISTRY

TECHNICAL IMMUNOHISTOCHEMISTRY

Immunohistochemistry Analysis of Proteins

Immunohistochemistry - WormBook

immunohistochemistry

Handbook of Practical Immunohistochemistry