多房性囊性肾细胞癌的临床病理学特征和分子遗传学观察

目的 探讨多房性囊性肾细胞癌(MCRCC)的临床病理及分子遗传学改变特征.方法 对1990年1月至2006年12月间第二军医大学附属长海医院病理科病理诊断为肾细胞癌(706例)中的21例MCRCC进行了光镜、免疫表型观察和微卫星不稳定性(MSI)及杂合性缺失(LOH)检测.结果 21例MCRCC患者年龄34～72岁(平均年龄50岁),男19例,女2例.肉眼或镜下血尿3例,18例因体检而偶然发现.10例肿瘤位于左肾,11例位于右肾.T1期18例,T2期2例,T3期1例.其中1例侵犯肾包膜,均无淋巴结转移.随访20例,无一例死于肾癌,未发现肾癌转移或复发病例.组织学观察,肿块最大直径0.3～10.0 cm(平均3.6 cm).切面呈多房性囊性,囊腔大小不等,囊腔间隔厚薄不均(0.1～0.5 cm.平均0.2 cm),内含淡黄色液体或胶冻样或血性液体.囊腔内衬单层或多层上皮细胞,胞质透明或淡嗜酸性.囊腔间隔内也可见呈巢状或腺泡状排列的透明细胞.Fuhrman 1级16例,Fuhrman 2级5例.免疫组织化学观察,瘤细胞波形蛋白、ABC、CAM5.2、上皮细胞膜抗原(EMA)均呈阳性表达,CD10阳性表达6例.神经元特异性烯醇化酶(NSE)阳性表达16例.分子遗传学观察,21例标本中,PCR扩增成功的有11例,5例发现微卫星变异,3例有LOH,其中D3S1560基因座2例,D14S617基因座1例;2例有MSI,分别为D9S168和D14S617各1例.结论 MCRCC是一种少见的肾囊性肿瘤,具有独特的临床和病理学特征,肿瘤预后良好,可通过手术切除而治愈.

Clinicopathologic features and molecular genetic analysis of multilocular cystic renal cell carcinoma

Objective To assess the clinicopathological features and molecular genetic changes of multilocular cystic renal cell carcinoma (MCRCC). Methods All the data reviewed were from the files of pathology department of Changhai hospital collected from 1990 to 2006. In totally 706 cases of renal cell carcinoma studied, there were 21 MCRCC cases identified. The clinical and pathological features were assessed, immunohistochemical staining was performed, and loss of heterozygosity (LOH) and microsatellite instability (MSI) were assessed using four microsatellite markers on chromosomes 3, 9 and 14. Results Of the 21 patients, the age ranged from 34 to 72 years ( mean 50 years), 19 were male and two female. Tumors were found incidentally in 18 patients during physical examination, three patients had anemia or microhematuria. Among the 21 patients, 10 tumors were in the left kidney and 11 in the right. Eighteen patients were stage T1, two stage T2, and one stage T3 with perinephric tissue involvement. Follow up information was available in 20 patients, all showed no evidence of tumor recurrence or metastasis. Grossly, the tumor size ranged from 0.3 cm to 10.0 cm in the greatest dimension, consisting of muhilocular cysts with variable sizes which contained light yellow, colloid or hemorrhagic fluid. The septae varied in thickness (ranged 0.1 cm to 0.5 cm, mean 0.2 cm). Microscopically the cysts were lined by single to muhilayered epithelial cells with clear or lightly eosinophilic cytoplasm. There were clusters of clear cells seen in the septae stroma. Sixteen tumors were of Fuhrman grade 1, and five were of Fuhrman grade 2. Immunohistochemically, the clear cells were positive for vimentin, ABC, CAMS.2 and EMA. Six samples were positive for CD10, and 16 were positive for NSE. Among 21 patients, PCR amplification was successful in 11 patients. Microsatellite alterations were found in five patients. LOH was observed in 3 of 11 MCRCC (27%), two were at D3S1560 locus, and one at D14S617 locus. MSI frequency was identified in 2 of 11 MCRCC (18%), locating at D9S168 or D14S617 locus, respectively. Conclusions MCRCC is an uncommon tumor of kidney, constituting 2.9% of all RCC enrolled into the study. It has distinctive clinical and pathological characteristics with an excellent outcome. Results indicated that MCRCC is a rare entity with low malignant potential.