具有低度恶性潜能的多房囊性透明细胞肾肿瘤17例临床病理学特征及分子遗传学分析

摘要

目的 探讨具有低度恶性潜能的多房囊性透明细胞肾肿瘤的临床病理学特征、免疫表型、分子遗传学改变及预后.方法 回顾性分析17例具有完整临床资料,可进行系统性评估及生存随访的低度恶性潜能的多房囊性透明细胞肾肿瘤,采用 HE及免疫组化EnVision两步法染色,观察并分析肿瘤的组织学特征及免疫表型;采用间期荧光原位杂交检测3号染色体短臂(3p)的杂合性缺失;并对所有患者进行随访.结果 17例中男性12例,女性5例,男女比为2.4 : 1.年龄28～73岁,平均54岁.多为偶然或体检发现肾脏占位.镜检:囊腔大多衬覆单层肿瘤细胞,局灶为双层或假复层,胞质透明、核小、未见明显核仁、WHO/ISUP核分级多为I级.纤维间隔内可见与囊腔衬覆细胞类似的透明细胞团.免疫表型:17例肿瘤细胞不同程度表达CK(AE1/AE3)、CK7、EMA、vimentin、CD10、碳酸酐酶 IX(CAIX)、PAX-2和 PAX-8,不表达 CD68,Ki-67增殖指数均 <17例患者中11例检测到3p染色体杂合性缺失,3P染色体杂合性缺失率为64.7％.结论 具有低度恶性潜能的多房囊性透明细胞肾肿瘤以囊性成分为主,具有低度恶性潜能,预后良好;其可能来源于肾小管中具有多向潜能分化的肿瘤干细胞;其与肾透明细胞癌在免疫表型和分子遗传学上相似,推测其可能是肾透明细胞癌的一种特殊组织学亚型.%Purpose To investigate the clinicopathological features, immunophenotype, molecular genetic alteration in multilocular cystic clear cell neoplasm of low malignant potential. Methods 17 cases of multilocular cystic clear cell neoplasm of low malignant potential with complete clinical data, systematic measurement and follow-up were retrospectively studied. Histopathological evaluation and immunophenotyping were examed by HE staining and EnVision two steps methods, chromosome 3p deletion was analyzed by interphase fluorescence in situ hybridization. Results In 17 cases, there were 12 males and 5 females, and the ratio of male and female was 2.4: 1. The prevalence age was at a range of 28-73 years, and the average age is54 years. Mostly of them were found by incidental or physical exmanination. Microscopically, most cysts were lined by a single layer of tumor cells with clear cytoplasm, small nuclear, and no obvious nucleoli. According to WHO/ISUP nuclear grade, they were level I. Clear cell groups similar to cells lined cysts were seen within the fibrous septa. Immunohistochemically, tumor cells were positive for CK(AE1/AE3), CK7, EMA, vimentin, CD10, CAIX, PAX-2, and PAX-8, but negative for CD68. Ki-67 index were less than 10％. The loss of heterozygosity of 3p chromosome was detected in 11 cases and the rate of the loss of heterozygosity was 64.7％. Conclusion Multilocular cystic clear cell neoplasm of low malignant potential is a relatively rare type of renal cell carcinoma with low malignant potential and a good prognosis. It is suggested that tumor cells may be derived from tumor stem cells with pluripotent potential in renal tubules based on the immunophenotypes. Multilocular cystic clear cell renal cell carcinoma and renal clear cell carcinoma is similar in immunophenotype and molecular genetics, which suggesting that it may be a special histologic subtype of renal clear cell carcinoma.