Here, we report a unique case of sarcomatoid chromophobe RCC in a 35âyearâ old ... KEY WORDS: Aggressive behavior, chromophobe renal cell carcinoma, ...
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E-JCRT Correspondence
Sarcomatoid chromophobe renal cell carcinoma: A rare entity with prognostic significance ABSTRACT Renal cell carcinoma (RCC) is the most common malignancy of the kidney and has multiple subtypes. The sarcomatoid variety is considered a form of dedifferentiated carcinoma. It is more commonly associated with clear cell variant but very few are associated with chromophobe RCC. When present, it is associated with a significant decrease in patient survival due to its rapid growth and intrusive behavior. Here, we report a unique case of sarcomatoid chromophobe RCC in a 35‑year‑ old woman. KEY WORDS: Aggressive behavior, chromophobe renal cell carcinoma, sarcomatoid dedifferentiation
INTRODUCTION Sarcomatoid renal cell carcinomas (RCC) of the kidney are rare neoplasms constituting about 1‑5% of all renal malignant neoplasms.[1] These are more commonly associated with conventional (clear cell) RCC but only very few cases are reported in the literature of sarcomatoid chromophobe renal cell carcinoma (CRCC) and metaplastic bone formation is extremely rare.[1] The first case of CRCC with concomitant osseous metaplasia and sarcomatoid transformation was reported in 2013 in Japan.[2] Although CRCC have been associated with a more favorable prognosis than clear cell carcinomas, sarcomatoid carcinomas signify a poor prognosis.[1] CASE REPORT A 35‑year‑old female patient presented with gross painless hematuria of three months duration. Abdominal computed tomography (CT) scan revealed large heterogeneous mass arising in the kidney with necrotic and cystic changes and areas of calcification. Nephrectomy was performed. We received a specimen of kidney measuring 14 × 9 × 8 cm. Cut section showed partly solid, partly cystic tumor replacing whole of kidney parenchyma, gray white in color with foci of hemorrhage, necrosis and calcification [Figure 1] Histopathological examination revealed two distinct morphological components of the tumor. The CRCC consisted of epithelial cells arranged in a nested pattern, and these were mixed with extensive areas of sarcomatoid spindle cells with marked nuclear pleomorphism and brisk
mitotic activity [Figure 2]. The tumor cells showed well‑defined cell borders, finely granular chromatin, raisinoid nuclei and perinuclear halo [Figure 3]. The tumor also contained multiple foci of metaplastic ossification. Histopathological diagnosis of sarcomatoid CRCC was made.
Reetika Sharma, Vijay Kaushal Department of Pathology, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India For correspondence: Dr. Reetika Sharma, Department of Pathology, Indira Gandhi Pradesh, Medical College, Shimla, Himachal Pradesh - 171 001, India. E-mail: dr_ritu85@ yahoo.com
DISCUSSION RCC accounts for 3% of adult malignancies and more than 90% of renal cancers.[3] The clear cell histologic subtype is by far the most common, comprising 70% of all cases. Other less common histologic subtypes include papillary, chromophobe and collecting duct, which represent 10%, 5% and less than 1% of all RCCs, respectively.[4] Sarcomatoid RCC is defined as any subtype containing foci of pleomorphic spindle cells and is seen in high‑grade RCC. Akhtar et al. suggested that sarcomatoid development in CRCC might be associated with its peculiar genetic profile, which makes cells prone tohyperploidization.[5] Brunelli et al. demonstrated that both the epithelial and sarcomatoid elements in a CRCC have different genetic abnormalities and that the latter show multiple gains of chromosomes 1, 2, 6, 10, and 17.[6] The coexistence of both CRCC and sarcomatoid carcinoma may be due to either the dedifferentiation of the more highly differentiated chromophobe cell tumor or the coincidental development of two synchronous tumors.
Access this article online Website: www.cancerjournal.net DOI: 10.4103/0973-1482.154059 PMID: *** Quick Response Code:
RCC can be associated with hemorrhage, necrosis, hyalinization and calcification but osseous
Journal of Cancer Research and Therapeutics - October-December 2015 - Volume 11 - Issue 4
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Sharma and Kaushal: Sarcomatoid RCC: A rare entity
mechanism of bone formation is unclear, but it could be due to metaplastic response or secondary to inflammation, ischemia or necrosis in the tumor or surrounding tissue. The significance of bone formation is unclear because only few cases are reported; however, according to some workers this phenomenon is seen in early stage and hence good prognosis, but some workers suggest that ossification in RCC is associated with high‑grade tumors and poor prognosis.[2]
Figure 1: Partly solid, partly cystic tumor replacing whole of kidney parenchyma, gray white in color with foci of hemorrhage and necrosis
Differential diagnosis of sarcomatoid RCC includes classic sarcoma and sarcomatous urothelial components if spindle cell component is predominant. Primary renal sarcomas are very rare, accounting for
