转移性恶性肾血管平滑肌脂肪瘤三例报告

Malignant renal angiomyolipoma with metastases （report of 3 cases）

目的探讨转移性恶性肾血管平滑肌脂肪瘤（AML）的诊断和治疗。方法转移性恶性AML患者3例。男1例，女2例。年龄分别为36、55和37岁。主诉为持续性患侧腰痛1～6个月。2例B超、CT检查发现患肾实性占位。1例B超见肾肿块内不均匀高回声光团，CT测得脂肪负值信号。2例行根治性肾切除术，1例行肾切除术。3例均未放化疗。结果肿块切面灰红、灰黄，质软。病理镜下观察：2例瘤细胞呈上皮样，核有异型，伴坏死；1例大多区域为梭形平滑肌，脂肪细胞和血管混杂生长，部分区域细胞呈上皮样。免疫组化结果均为VM（＋），HMB45（＋），Melan—A（＋），S-100（-），CK（-）。3例病理诊断均为恶性肾AML，2例为上皮样型，1例为经典型、部分上皮样型。1例术后7年出现肺转移，行肺叶切除加清扫，随访12年无瘤生存。1例术后6年复发，行肿块切除术；术后10年发现肝、后腹膜转移，再行肿块部分切除，随访12年带瘤生存。1例术后4个月出现肝、后腹膜转移，行肿块部分切除，3个月后失访。结论恶性肾AML罕见，诊断依靠病理和免疫组化检查。治疗方法无特殊。

Objective To study the diagnosis and treatment of malignant renal angiomyolipoma with metastases. Methods Three cases of advanced malignant renal angiomyolipoma with metastases were retrospectively reviewed. Case 1 was a 55-year-old woman presenting with recurrent lowgrade fever and aching pain in left flank. Ultrasound showed solid mass in the left kidney. Left radical nephrectomy was then performed. The right pulmonary lohectomy of the inferior lobe and wedge exsection of superior lobe was performed 7 years later because of multiple pulmonary metastases. Case 2 was a 37 year-old woman. Left nephreetomy was performed because Ultrasound and CT showed left kidney solid mass. Six years later, multi-site metastases were found in liver and retroperitoneum and mestastasis tumors were resected. At 10 years after the primary diagnosis, CT showed multi-metastases in liver and retroperitoneum. The retroperitoneal masses were resected and liver lesions were treated by radiofrequency ablation. Case 3 was a 34-year-old man presenting with swelling pain in right flank. CT scan showed a lesion in the right kidney and right radical nephrectomy was performed. Four months after the surgery, MRI revealed multiple liver and retroperitoneal nodules. All the 3 cases had not been diagnosed with tuberous sclerosis and did not accept chemotherapy. Results The cut surface of the lesions was red-brown and yellow and the texture was tender. Under microscopic examination, the tumors of case 1 and case 3 were composed of sheets or nests of large polygonal epithelioid cells. It revealed that occasionally clear cytoplasm with abundant eosinophilic, prominent nucleoli, and multinucleated and markedly pleomorphic form. Necrosis was presented as well. Large areas of case 2 tumor were made up of spindle smooth-muscle cells, adipose tissue, thick-wall blood vessels and some areas merged with a proliferation of epithelioid which was consistent with typical angiomyolipoma. Ira-munohistochemical study showed that the epithelioid cells and spindle smooth-muscle cells were positive for VM, HMB45, Melan-A and negative for S100, CK. Case 1 and case 3 were diagnosed with malignant epithelioid angiomyolipoma, while case 2 was diagnosed with malignant classic angiomyolipoma and epithelioid in part of the tumor. Case 1 was well alive. Case 2 was alive with tumor 12 years after the diagnosis. And case 3 was missed in the follow-up 3 months after metastasis resectin. Conclusions Malignant renal angiomyolipoma is a rare disease. The diagnosis depends on histopathologic, immunohistochemical study and clinical follow-up. Radical resection of the primary, recurrent and metastatic tumors is the main therapy. It needs more research to clarify if metastasis has any effect on prognosis.