肾上皮样血管平滑肌脂肪瘤临床特点分析

Epithelioid angiomyolipoma of the kidney

目的 探讨肾上皮样血管平滑肌脂肪瘤的临床及病理特点.方法 肾上皮样血管平滑肌脂肪瘤患者6例.单发4例,多发2例.肿瘤直径平均9（5～14）cm.有结节硬化家族史1例.CT检查发现肿瘤内含脂肪组织（CT值-30～-120 HU）3例,诊断为肾血管平滑肌脂肪瘤;3例瘤组织CT值30～55 HU,增强扫描CT值70～110 HU.行肿瘤剜除术3例,行根治性肾切除术3例.结果 3例行肿瘤剜除术者肿瘤完整剜除,2例出现肾盂破损,行肾盂修补及留置双J管.其中1例双肾肿瘤者,2个月后手术剜除对侧肿瘤.3例根治性肾切除者完整切除肾脏、肾周脂肪组织及肿大淋巴结.病理检查：镜下肿瘤以上皮样细胞为主,并出现多形、异形核,有明显的上皮样分化,浸润破坏性生长,瘤组织广泛坏死.免疫组化染色HMB45（＋＋＋）,EMA、CK（-）.病理诊断均为肾上皮样血管平滑肌脂肪瘤.平均随访26（10～44）个月,肿瘤无复发及转移5例;1例根治术后18个月出现双肺转移,10个月后死亡.结论 肾上皮样血管平滑肌脂肪瘤多为良性,部分缺乏脂肪组织,主要由单核或多核的上皮样细胞构成,免疫组化染色HMB45强阳性为特征表现,具有潜在恶性倾向,可发生转移;CT检查易误诊为肾癌;手术为主要治疗方法.

Objective To investigate the clinicopathologic features of epithelioid angiomyolipoma of renal（REAML）. Methods Six cases of REAML were analyzed by histopathological and clinical characteristics.Of the 6 cases,4 cases were solitary tumors and 2 cases were multiple lesions.The diameter of tumors was about 9 cm in average.One case had a family history of nodular sclerosis.Three cases were found adipose tissue in CT scan and diagnosed for RAML,the other 3 cases were diagnosed for renal cancer.All cases were undergone surgical approach,3 cases were undergone resection of tumors only and the other 3 were performed nephrectomy. Results Pathological characters：tumor was mainly composed of epithelioid cells presented with invasive hyperplasia of atypical pleomorphism,hyperchromatic nuclei with frequent mitotic figures,giant neoplasic cells and extensive hemorrhagic necrosis immunohistochemcial staining showing a positive HMB45 and negative of EMA,CK in most neoplasic cells.All cases were followed up for 10 to 44 months,5 cases did not recurrence and metastases;the other had lung metastasis after operation 18 months later,without any treatment the patient died 10 months later. Conclusions Most of REAMLs are benign and often misdiagnosed for renal cancer by CT scan.HMB45 is positive in immunohistochemcial staining available for diagnose.The minority of REMAL is malignant potentially and should be followed up closely.Operation is major method.