摘要目的 分析和总结后肾腺瘤的临床、影像学及病理学特征.方法 利用光镜观察及免疫组织化学EnVision法分析8例后肾腺瘤,并结合文献讨论其临床影像学特点、病理诊断、鉴别诊断、治疗和预后.结果 患者女性6例,男性2例,年龄12 ～ 70岁,平均年龄43.6岁.肿瘤界清,均位于肾实质的皮质区,镜下观察见水肿的间质中嗜碱性瘤细胞排列成小腺泡状,灶性区可见乳头状结构,偶可见钙化或沙砾体形成;免疫组织化学染色中,肿瘤细胞PAX2、波形蛋白均阳性表达,WT-1表达局灶或弱阳性5例、阳性2例、阴性1例,广谱CK表达阳性3例,CK7表达阴性7例、局灶阳性1例,CD10、肾细胞癌标志物(RCC)、上皮细胞膜抗原、突触素、嗜铬粒素A均阴性.7例Ki-67阳性表达＜2％、1例局灶区约5％.8例获得随访,时间7 ～ 57个月,均未出现复发或转移.结论 后肾腺瘤的诊断需依据独特的组织学特征,免疫表型表现为波形蛋白、PAX2恒定表达,部分病例WT-1有局灶或弱阳性表达,Ki-67阳性表达率低,其诊断需有临床及影像学资料的支持.

abstractsObjective To study the clinical and histopathologic features of metanephric adenoma (MA).Methods Eight cases of recently diagnosed MA were retrieved from archival file.Immunohistochemical study was carried out.The clinical characteristics,pathologic parameters,differential diagnosis,treatment options and prognosis of MA were analyzed,with literature review.Results The patients included 6 females and 2 males.The age of patients ranged from 12 to 70 years (mean =43.6 years).Eight cases were located in renal cortex and showed well-defined borders.Histologically,the tumor was composed of tubules lined by small basophilic cells and embedded in an edematous stroma.Papillary structures and psammoma bodies were focally seen.Immunohistochemical study showed that the tumor cells were positive for PAX2 and vimentin in all the 8 cases.WT-1 was positive in 2 cases,focal and weak in 5 cases,and negative in 1 case.CK-Pan was positive in 3 cases.CK7 staining was mostly negative,with focal and weak positivity only in 1 case.The proliferative index,as highlighted by Ki-67 staining,was less than 2％ in 7 cases and focally around 5％ in 1 case.The expressions of CK20,CD10,RCC,epithelial membrane antigen,CD56,synaptophysin and chromogranin A were negative.Follow-up information from 7 to 57 months was available in all patients; and none of them developed local recurrence or distant metastasis.Conclusions The diagnosis of MA relies primarily on thorough histologic examination and immunohistochemical study (vimentin and PAX2 positive,WT-1 focally and weakly positive in some cases,and low proliferative index).Correlation with clinical and radiologic findings would also be helpful.