DeLong W, Grignon D J, Eberwein P, Shum D T, Wyatt J K
Department of Pathology, Victoria Hospital, London.
Arch Pathol Lab Med. 1993 Jun;117(6):636-40.
Malignant spindle cell neoplasms are a diagnostic challenge regardless of their location. In the retroperitoneum a major consideration in the differential diagnosis is sarcomatoid renal cell carcinoma; if an epithelial component cannot be recognized histologically, special studies may be required to reach the correct diagnosis. In an attempt to better characterize this entity, 23 cases of sarcomatoid renal cell carcinoma (6.3%) were identified from a review of 363 renal cell carcinomas. Blocks were available for immunohistochemical analysis in 18 cases. The epithelial and sarcomatoid portions were studied with a panel of antibodies directed against cytokeratin (AE1/AE3, CAM 5.2, and 34 beta E12), epithelial membrane antigen, Leu-M1, muscle-specific actin, S100 protein, desmin, and vimentin. The epithelial nature of the spindle cell component was best demonstrated by positive reactivity with the anti-cytokeratin AE1/AE3 (in 17 [94%] of the 18 cases). The other epithelial markers stained the spindle cell component less frequently: cytokeratin CAM 5.2 in seven cases (39%); epithelial membrane antigen in nine cases (50%); and high-molecular-weight cytokeratin 34 beta E12 in no cases (0%). In 10 cases (56%) vimentin positivity and in six cases (33%) actin positivity was seen in the spindled areas. The spindle cell component stained for Leu-M1 in four cases (22%) and for S100 protein in one case (6%) and did not react for desmin in any case. From this study we conclude that in the majority of sarcomatoid renal cell carcinomas the epithelial nature of the spindle cells, as indicated by cytokeratin expression, can be documented using immunohistochemical methods.
恶性梭形细胞瘤无论位于何处，在诊断上都具有挑战性。在腹膜后，鉴别诊断的一个主要考虑因素是肉瘤样肾细胞癌；如果在组织学上无法识别上皮成分，则可能需要进行特殊检查才能做出正确诊断。为了更好地描述这一实体，我们在回顾363例肾细胞癌时，识别出了23例肉瘤样肾细胞癌（占6.3%）。其中18例有组织块可用于免疫组化分析。我们用一组针对细胞角蛋白（AE1/AE3、CAM 5.2和34βE12）、上皮膜抗原、Leu-M1、肌肉特异性肌动蛋白、S100蛋白、结蛋白和波形蛋白的抗体，对上皮和肉瘤样部分进行了研究。梭形细胞成分的上皮性质通过与抗细胞角蛋白AE1/AE3呈阳性反应得到了最佳证明（18例中有17例[94%]）。其他上皮标记物对梭形细胞成分的染色频率较低：细胞角蛋白CAM 5.2在7例（39%）中呈阳性；上皮膜抗原在9例（50%）中呈阳性；高分子量细胞角蛋白34βE12在任何病例中均未呈阳性（0%）。在10例（56%）的梭形区域中可见波形蛋白呈阳性，在6例（33%）中可见肌动蛋白呈阳性。梭形细胞成分在4例（22%）中对Leu-M1呈阳性染色，在1例（6%）中对S100蛋白呈阳性染色，在任何病例中对结蛋白均无反应。从这项研究中我们得出结论，在大多数肉瘤样肾细胞癌中，通过细胞角蛋白表达所表明的梭形细胞的上皮性质，可以用免疫组化方法记录下来。
