成人肾恶性横纹肌样瘤临床与病理学特点分析

Malignant rhabdoid tumor of the kidney in adults: a clinical and pathologic study

目的探讨成人肾恶性横纹肌样瘤(MRTK)的临床及病理学特点。方法结合文献回顾性分析5例成人MRTK患者的临床和病理资料。男4例,女1例。年龄21～67岁,平均50岁。其中左侧3例,右侧2例。3例有肉眼血尿、腰痛不适和腹部包块等症状,体检发现右肾肿物1例,查体仅1例表现低热,未见其他阳性发现。结果5例均行根治性肾切除。肿瘤平均直径6．5 cm。NWTS分期Ⅱ期4例,Ⅲ期1例。病理特点：MRTK细胞有丰富的嗜酸性胞质,部分胞质内有大圆形嗜酸性包涵体,核分裂多。免疫组织化学染色波形蛋白、上皮膜抗原阳性。电镜观察：胞质内见中间丝及圆形、不规则形纤维状或轮状小体。4例获随访3～24个月,2例术后1年死于转移或并发症,2例无瘤存活6个月。结论MRTK是一种具有特殊形态的少见肾癌类型,与同期、同级其他类型肾癌比较预后较差,成人预后好于青少年。

Objective To study the pathologic and cliuical features of malignant rhabdoid tumor of the kidney （MRTK） ,and to improve the diagnosis and treatment of the disease. Methods The clinical and pathologic data of 5 patients （4 men and 1 woman; mean age ,50 years ; age range,21 - 67 years） with MRTK （3 tumors on the left and 2 on the right） were retrospectively analyzed in combination with review of the relevant literature. Of the 5 cases, 1 was incidentally diagnosed with renal tumor during physical examination;and 3 had gross hematuria,low back pain and discomfort, and abdominal masses. Results Radical nephreetomy was performed in all 5 cases, The tumors averaged 6.5 cm in diameter. By NWTS staging,4 cases had stage Ⅱ tumors and 1 case had stage Ⅲ tumor. Pathological features were as follows. Rhabdoid ceils were characterized by eccentric nuclei, prominent nucleoli, and abundant cytoplasm containing eosinophilic inclusions that were strongly positive for vimentin and epithelial membrane antigen （EMA）. Electron microscopy showed intermediate filaments and round, irregular fibroid or whorl-like corpuscles in the cytoplasm. Follow-up was available in 4 patients （ mean,6.8 months;range ,3 - 24 months）. Of them ,2 died of metastasis or complications 12 months after operation; avd 2 were alive without recurrence and metastasis for 6 months. Conclusions MRTK is a rare and morphologically distinctive neoplasm with specific findings of pathological features, The tumor has a poorer prognosis ,but comparatively it is better in adults than in adolescents.