âA Review of Cases from a Single Institution ... The levels of sacral resection were S3 in 1 patient,. ï¼. ï¼. ï¼ ... otherapy as neo-adjuvant or adjuvant therapy.
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Mucinous Adenocarcinoma Associated with a Chronic Perianal Fistula ―A Review of Cases from a Single Institution ＊1,2
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Fumikazu Koyama , Tadashi Nakagawa , Shinji Nakamura , Takeshi Ueda , ＊1 ＊1 ＊1 ＊1 Naoto Nishigori , Takashi Inoue , Keijiro Kawasaki , Shinsaku Obara , ＊1 ＊1 ＊2 ＊3 Takayuki Nakamoto , Kazuaki Uchimoto , Hisao Fujii , Akira Kido , ＊3 ＊4 ＊4 ＊5 Yasuhito Tanaka , Katsunori Yoshida , Kiyohide Fujimoto , Masamitsu Kuwahara ＊1 and Yoshiyuki Nakajima 〔 Jpn J Cancer Chemother 4112: 1866-1868, November, 2014〕
Summary Purpose: The purpose of this study was to evaluate the clinicopathological features of mucinous adenocarcinoma associated with perianal fistulas（MAF), to assess the importance of preoperative MRI analysis, and to determine the optimal surgery. Methods: We performed a retrospective analysis of the data from seven patients with MAF treated at our hospital between 2000 and 2013, and herein discuss the importance of preoperative magnetic resonance imaging（MRI）and of radical surgery. Results: The male to female ratio was 5：2, and the mean age of the patients was 63 years old（28-70). The median duration of chronic fistulation was 16 years（5-40). The tumor extension was classified as Ⅱ＋Ⅲ＋Ⅳ in five patients and as Ⅱ＋Ⅲ in 2 patients according to the Sumikoshi classification, as determned by pelvic MRI. The performed surgeries were 3 abdominoperineal resections with sacral resection and 4 pelvic exenterations with sacral resection. Two local recurrences developed in patients with R1 resection, and 1 distant metastasis occurred in 1 patient with R0 resection. Conclusion: For patients with MAF, a curative surgical resection is the only definitive treatment that can be expected to provide a good prognosis. The application of the Sumikoshi classification using MRI may provide a precise assessment of the extension of MAF, which can allow the appropriate surgery to be selected for the patients with MAF. Key words: Mucinous adenocarcinoma, Anal fistula, Sumikoshi classification 姻姻姻姻姻姻姻姻姻姻姻姻姻姻姻姻姻
Introduction
Ⅰ．Patients and methods
A chronic perianal fistula is a common clinical condition. However, the experience of managing mucinous adenocarcinoma associated with a chronic perianal fistula is limited, because such tumors are rare. Surgical resection is thought to be the most important therapeutic option, which often requires an extended tumor resection along with the resection of the fistu1 la-forming organs . Radiotherapy with or without chemotherapy can be used as adjuvant therapy, but its long-term results 1-3 are controversial . Local recurrence is more common than 4 distant metastasis . No optimal treatment for mucinous adenocarcinoma associated with a perianal fistula has been established. We herein report the case of seven patients with mucinous adenocarcinoma associated with anal fistulas（MAF）experienced at our hospital, and discuss the importance of the findings of preoperative magnetic resonance imaging（MRI）and the efficacy of radical surgery.
Seven patients with MAF underwent radical surgery at our hospital between 2000 and 2013. We reviewed the medical records retrospectively and gathered patient characteristics and surgical data, such as the age, gender, fistula duration, tumor extension, surgical method, length of operation, blood loss, morbidity and mortality, histology, TNM stage, margin status and patient outcome. We evaluated the tumor extension by MRI preoperatively and classified the tumors according to the Sumikoshi classification of anal fistulas（Ⅰ＝subcutaneous fistula, Ⅱ＝intersphincteric fistula, Ⅲ＝ischiorectal fistula, Ⅳ＝pelvirectal fistula5. We considered the optimal surgery for MAF by assessing the relationship between tumor extension and the surgical method, and the relationship between the margin status and patient outcome.
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Dept. of Surgery, Dept. of Endoscopy and Ultrasound, Division of Plastic Surgery, Nara Medical University
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Ⅱ．Results The patient characteristics are shown in Table 1. The me-
Dept. of Orthopedics,
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Dept. of Urology, and
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Dept. of Dermatology,
Corresponding author: Fumikazu Koyama, Department of Surgery, Department of Endoscopy and Ultrasound, Nara Medical University, 840 Shijo-cho, Kashihara City, Nara 634-8522, Japan
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Table 1 Case A B C D E F G
2014 年 11 月
The clinicopathological features of mucinous adenocarcinomas associated with perianal fistulas in 7 patients
Age（y)／ ／ Tumor gender extension 70／M ／ 64／M ／ 63／M ／ 62／M ／ 28／F ／ 65／M ／ 43／F ／
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Ⅱ＋Ⅲ＋Ⅳ Ⅱ＋Ⅲ Ⅱ＋Ⅲ Ⅱ＋Ⅲ＋Ⅳ Ⅱ＋Ⅲ＋Ⅳ Ⅱ＋Ⅲ＋Ⅳ Ⅱ＋Ⅲ＋Ⅳ
Perineal Radical Resection reconstursurgery of muscle uction APRS APRS APRS PPES PPES TPES TPES
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Obt Obt Obt＋Coc Obt＋Coc
VRAM VRAM Gracilis Gluteus
Histology
Stage
Tub1＞Muc Muc Muc Muc Muc Muc Tub2＞Muc
Ⅱc Ⅱc Ⅱc Ⅲc Ⅱc Ⅱc Ⅱc
Post-op. Margin survival Recurrence status （months) R1 R0 R0 R1 R0 R0 R0
31 89 114 48 32 30 18
Local ― ―
Local Brain／lung ／ ― ―
Outcome Died Alive Alive Died Died Alive Alive
The tumor extension was classified according to the Sumikoshi classification of anal fistulas. APRS: abdomino-perineal resection with sacral resection, PPES: partial pelvic exenteration with sacral resection, TPES: total pelvic exenteration with sacral resection, Obt: obturator muscle, Coc: coccygeal muscle, VRAM: vertical rectus abdominis myocutaneous flap, Gracilis: gracilis myocutaneous flap, Gluteus: gluteal myocutaneous flap, Tub1: well differentiated tubular adenocarcinoma, Tub2: moderately differentiated tubular adenocarcinoma, Muc: mucinous adenocarcinoma
a
Fig. 1
Case B a: The horizontal view obtained by T2-weighted pelvic MRI revealed a honeycomb-like invasion of mucinous adenocarcinoma with malignant mucinous pools in the intersphincteric space and ishiorectal fossa（Sumikoshi classification Ⅱ＋Ⅲ). b: The resected specimen at the same level showed the honeycomb structure of the mucinous adenocarcinoma.
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Fig. 2
b
b
c
Case C a: A horizontal view obtained by T2-weighted MRI revealed a large malignant mucinous pool that had formed in the retrorectal space. The white dotted lines indicate the resection line. b: As sagittal view obtained by MRI revealed that the malignant mucinous pool extended to the ischiorectal fossa（Sumikoshi classification Ⅲ）and to the lower sacrum. c: The resected specimen.
dian age at the time of diagnosis was 63（range 28-70）years. Five patients were male and 2 patients were female. The median duration of chronic perianal fistulation was 16（range 540）years. Fig. 1 and Fig. 2 show the pelvic MRI findings and the resected specimens from representative cases. The tumor extension was classified as Ⅱ＋Ⅲ＋Ⅳ in 5 patients and as Ⅱ＋Ⅲ in 2 patients by pelvic MRI.
The performed surgeries were 3 abdomino-perineal resections with sacral resection, 2 partial pelvic exenterations with sacral resection, and 2 total pelvic exenterations with sacral resection. The levels of sacral resection were S3 in 1 patient, S3／4 ／ in 1 patients, S4／5 ／ in 3 patients, and S5／Coccyx ／ in 2 patients. The combined circumferential muscular structures resected were the unilateral obturator and coccygeal muscles in
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2 patients, and the unilateral obturator muscle in 2 patients. Perineal reconstruction was required in 4 patients, including 2 vertical rectus abdominis myocutaneous flaps, 1 gracilis myocutaneous flap, and one gluteal myocutaneous flap. These extensive surgeries required 910 minutes as the median length of the operation（range 655-1, 082）and the median blood loss was 5, 250（2, 100-8, 000）mL. Postoperative complications occurred in all patients, including 5 cases of pelvic sepsis and three cases of wound dehiscence. The median duration of the postoperative hospital stay was 66（range 51-162）days. Fortunately, there were no postoperative hospital death in these patients. In terms of histology, mucinous adenocarcinoma was diagnosed in 5 patients and tubular adenocarcinoma with mucinous adenocarcinoma was diagnosed in 2 patients. The TNM stage were Ⅱc in 6 patients and Ⅲc only in one patient. No patients received radiotherapy as neo-adjuvant or adjuvant therapy. One patient （Case G）received seven cycles of chemotherapy（XELOX） as adjuvant therapy. After a median postoperative follow-up of 32（range 18114）months, 2 local recurrences developed in patients with R1 resection, and 1 distant metastasis was found in 1 patient with R0 resection. Four patients were alive without recurrence, and the 3 patients died from recurrent disease. Ⅲ．Discussion In our study, all patients had locally advanced tumors in the pelvic space without distant metastasis at the time of the operation. Only 1 case had left obturator lymph node metastasis （Case D). Local recurrence was seen in 2 patients with a positive circumferential resection margin（R1 resection). Four of the 5 patients with R0 resection have had no recurrence for 18 to 114 months after surgery. Yamada also previously reported that there was no nodal involvement in 7 patients with adenocarcinoma associated with an anal fistula, while local recurrence developed in 2 patients with R1 resection 4). These findings indicate the importance of a precise preoperative assessment of the extension of the tumor and of the importance of R0 resection on the treatment of the MAF. Recently, MRI has emerged as an important imaging mo6) dality in the management of perianal fistulas . T1-weighted （W）images are ideal for anatomically delineating the sphincter complex, pelvic floor and ischiorectal fossa. T2W images demonstrate hyperintense fluid within the tract in constrast to 6,7) the hypointense fibrous wall of the fistula . In this study, we
evaluated the extension of MAF by MRI. T2W images showed hyperintense large tumors（malignant mucinous pools）in the retrorectal space, with extension to the ischiorectal fossa, perineum and lower sacrum in all patients, which made it easy to classify the MAF using the Sumikoshi classification（Fig. 1 and Fig. 2). Type Ⅱ＋Ⅲ tumors required abdomino-perineal resection with sacral resection（APRS）for curative resection. In the type Ⅱ＋Ⅲ＋Ⅳ tumors, an APRS resulted in R1 resection, while 3 of the 4 pelvic exenterations with sacral resection（PES）succeeded in a R0 resection. Our findings suggest that the application of the Sumikoshi classification using MRI provided a precise assessment of the extension of MAF, which accelerated the selection of the appropriate surgery for the patients with MAF. Conclusion For patients with MAF, a curative surgical resection is the only definitive treatment which is expected to provide a good prognosis. The application of the Sumikoshi classification using MRI may provide a precise assessment of the extension of the MAF. Surgeons should not hesitate to perform pelvic exenteration combined with lower sacrectomy and resection of the circumferential muscular structures in order to ensure a tumor free margin status. References 1) Gaertner WB, Hagerman GF, Finne CO, et al: Fistula-associated anal adenocarcinoma: good results with aggressive therapy. Dis Colon Rectum 51(7): 1061-1067, 2008. 2) Jensen SL, Shokouh-Amiri MH, Hagen K, et al: Adenocarcimona of the anal ducts. A series of 21 cases. Dis Colon Rectum 31(4): 268-272, 1988. 3) Yang BL, Shao WJ, Sun GD, et al: Perianal mucinous adenocarcinoma arising from chronic anorectal fistulae: a review from single institution. Int J Colorectal Dis 24(9): 10011006, 2009. 4) Yamada K, Miyakura Y, Koinuma K, et al: Primary and secondary adenocarcinomas associated with anal fistulae. Surg Today 44(5): 888-896, 2014. 5) Iwadare J: Sphincter-preserving techniques for anal fistulas in Japan. Dis Colon Rectum 43(10 Suppl): S69-S77, 2000. 6) Gage KL, Deshmukh S, Macura KJ, et al: MRI of perianal fistulas: bridging the radiological-surgical divide. Abdom Imaging 38(5): 1033-1042, 2013. 7) Hama Y, Makita K, Yamana T, et al: Mucinous adenocarcinoma arising from fistula in ano: MRI findings. AJR Am J Roentgenol 187(2): 517-521, 2006. 本論文の要旨は第 36 回日本癌局所療法研究会において発 表した。
