肾源性腺瘤临床病理和免疫组化分析

Nephrogenic adenoma:clinicopathological and immunohistochemical analyses

目的探讨肾源性腺瘤(nephrogenic adenoma,NA)的临床病理表现和免疫组化特征。方法收集5例膀胱和输尿管NA,分析其临床病理和免疫表型特征。结果 3例NA位于膀胱,2例位于输尿管。眼观NA呈乳头状或息肉状,镜下见病变主要由增生上皮细胞形成的小管状、囊状和乳头状结构组成;增生上皮为单层立方状或扁平状,部分呈"鞋钉"样;间质慢性炎。免疫组化染色示增生上皮细胞呈PAX2、CK7、EMA、AMACR/P504S(+),p63、CD10、CD31、PSA(-),Ki-67增殖指数<2%。结论 NA是较少见的瘤样病变,可误诊为其他肿瘤(甚至腺癌)。熟悉其病理学和免疫表型特征是正确诊断的关键。

Purpose To analyze the clinicopathological and immunohistochemical features of nephrogenic adenoma （NA） in the urinary tract. Methods Five cases of nephrogenic adenoma in the urinary bladder and ureter were evaluated by histopathology and immunohistochemistry with review of the literature on its etiology, pathogenesis, and clinieopathological features. Results Three of the cases were from the urinary bladder and two from the ureter. The lesions appeared as a mucosal papillary or polypoid mass macroscopically, and were consisted of tubules, cysts or papillary structures lined by cuboidal, flat, or hobnail-like epithelial cells microscopically. Immunohistochemical staining showed that the epithelial ceils were positive for PAX2, CK7, EMA, and AMACR/P504S, but negative for PSA, CD10, p63 and CD31. The Ki-67 labeling index was less than 2%. Conclusions Nephrogenic adenoma is a rare tumor-like lesion that may be misdiagnosed as epithelial tumors such as adcnocarcinoma. Awareness of the entity and familiarity with its clinicopathological and immunohistochemical features are the keys to the correct diagnosis.