Nagashima Y, Okudela K, Osawa A, Nakamura N, Kawasaki C, Moriyama M, Nakamura N, Nakatani Y, Kitamura H, Aoki I
Department of Pathology, Yokohama City University School of Medicine, Yokohama, Japan.
Pathol Res Pract. 2000;196(9):647-51; discussion 652. doi: 10.1016/s0344-0338(00)80008-4.
Chromophobe renal cell carcinoma (RCC) is a newly established entity of renal neoplasm with histological and molecular biological features different from those of common RCCs. Chromophobe RCC shows characteristically cloudy and reticular cytoplasm and cellular features resembling distal nephron. Its prognosis has been reported to be more favorable than that of common RCCs. Recently, however, several cases have been reported which showed sarcomatoid change to present poor prognosis. Here we present a case of chromophobe RCC with sarcomatoid change which was once resected surgically. The surgically resected tumor was histologically composed of chromophobe epithelial cell sheets and sarcomatoid elements. The former showed positivity for colloid iron staining, and was immunohistochemically positive for E-cadherin and epithelial membrane antigen (EMA), whereas the latter was positive for vimentin instead of colloid iron and E-cadherin. EMA was focally positive in the sarcomatoid element. The patient died with systemic metastases 14 months after the operation. Histologically, the metastatic tumors were composed only of sarcomatoid element lacking epithelial element. Based on these findings and previous reports, this case supports the existence of a tumor progression pathway from chromophobe to sarcomatoid RCC. It is necessary to perform careful postoperative investigation of chromophobe RCC due to its possible histological progression to the sarcomatoid subtype.
嫌色性肾细胞癌（RCC）是一种新确定的肾肿瘤实体，其组织学和分子生物学特征不同于常见的肾细胞癌。嫌色性肾细胞癌的特征是细胞质呈云雾状和网状，细胞特征类似于远端肾单位。据报道，其预后比常见的肾细胞癌更有利。然而，最近有几例报告显示发生了肉瘤样改变，预后较差。在此，我们报告一例曾接受手术切除的伴有肉瘤样改变的嫌色性肾细胞癌病例。手术切除的肿瘤在组织学上由嫌色上皮细胞片和肉瘤样成分组成。前者胶体铁染色呈阳性，免疫组化E-钙黏蛋白和上皮膜抗原（EMA）呈阳性，而后者波形蛋白呈阳性，胶体铁和E-钙黏蛋白呈阴性。EMA在肉瘤样成分中呈局灶性阳性。患者术后14个月死于全身转移。组织学上，转移瘤仅由缺乏上皮成分的肉瘤样成分组成。基于这些发现和先前的报告，该病例支持存在从嫌色性到肉瘤样肾细胞癌的肿瘤进展途径。由于嫌色性肾细胞癌可能在组织学上进展为肉瘤样亚型，因此有必要对其进行仔细的术后检查。
