后肾间质肿瘤的病理观察

目的观察后肾间质肿瘤的临床病理表现,探讨其有病理诊断价值的组织学特征。方法对2例后肾间质肿瘤进行HE染色及免疫组织化学染色（EnVision法）,并进行观察。结果后肾间质肿瘤为单侧性肾占位,肿瘤位于肾髓质,边界清,呈“扇贝形”与相邻肾组织连接。镜下主要表现为：肿瘤内可见单个的肾小球和肾小管,梭形或星形肿瘤细胞呈“葱皮样”围绕肾小管和肾血管排列,细胞分布不均匀,在低倍镜下形成“结节样”图像;大部分肿瘤中内陷的小血管壁发育不良。肿瘤细胞CD34阳性表达。结论近肾小管区细胞和血管组成的“结节样”图像和CD34阳性是具有诊断和鉴别诊断价值的组织学特征。

Metanephric stromal tumor: a pathologic study of two cases

OBJECTIVE: To study the clinicopathologic features of metanephric stromal tumor (MST), with emphasis on diagnostic criteria. METHODS: The clinicopathologic findings in 2 cases of MST were analyzed and the literature of this entity was reviewed. RESULTS: Cases of MST were unilateral and mostly centered in renal medulla. The tumor was separated from adjacent renal tissue by sharp and scalloped borders. Entrapped tubules and glomeruli were commonly seen within the lesion. The tumor cells were spindle to stellate in shape and arranged in a nodular pattern. On low power examination, alternating areas of high and low tumor cellularity were noted. Characteristically, there were onion skin-like concentric cuffs of tumor cells around entrapped tubules. The small intratumoral vasculatures showed irregular thickening ("angiodysplasia"). Immunohistochemical study demonstrated that the tumor cells diffusely expressed CD34. CONCLUSIONS: Which the tumor cells around the entrapped renal tubules and blood vessels imparts a nodular appearance, as well as the tumor cells labbed for CD34 are the highly characteristic pathologic findings of MST.