肝脏血管平滑肌脂肪瘤临床病理特点分析

Hepatic angiomylipoma: report of 3 cases and review of literature

目的探讨肝脏血管平滑肌脂肪瘤(hepatic angiomylipoma,HAML)的临床病理特点、诊断及鉴别诊断。方法对3例HAML进行临床病理学观察及免疫组化标记并复习有关文献。结果 3例HAML,年龄分别为46岁,38岁和16岁,均无结节硬化症。术前影像诊断为肝占位。眼观:肿瘤直径7~20cm,肿瘤境界清楚,无包膜,质地脆、易碎,可见出血、坏死。镜检:瘤组织由上皮样细胞、平滑肌样细胞、脂肪组织和厚壁血管组成。上皮样细胞体积大或巨大,呈多边形,胞质丰富,嗜酸性或空泡状,核仁明显。平滑肌样细胞呈梭形,瘤细胞弥漫性或巢团状排列。免疫组化标记:3例病例标本均表达Melan-A,例二和例三表达HMB45,例一和例二表达S-100。SMA和CD34三例病例均表达。Ki-67例一约10%(+),例二和例三均<5%(+)。结论HAML是一种罕见的间叶组织源性肿瘤,组织学上由上皮样细胞、平滑肌样细胞、脂肪组织和厚壁血管组成,瘤细胞较为特异的表达Melan-A、HMB45及S-100。免疫组化标记可与其它肝脏肿瘤鉴别。

Objective To investigate the clinicopathological features and differential diagnosis of hepatic angiomyolipoma(HAML). Methods Three cases of HAML were analyzed by gross examination,light microscopy and immunohistochemistry. Moreover,the literature of this tumor were reviewed to discuss the histologic feature of HAML and its clinical behavior. Results The age at diagonosis,of three cases were 46,38 and 16 years. Three cases had no evidence of tuberous sclerosis. The diagnosis before operation by iconography was liver mass. Grossly,the greatest dimension of 3 tumors were 7-20 cm. All tumors had clear margins,had no envelope and showed fraility. Hemorrhage and necrosis could be seen in tumors. Microscopically,hepatic angiomyolipoma was composed of four tissue components including epithelioid cells,smooth myoid cells,thick-walled vessesl and adipose cells.The epithelioid cells were large and had eosinophilic or clear cytoplasm. The smooth myoid cells were spidle and the neoplastic cells were diffuse or nests in arrangement. Immunohistochemistry,the epithelioid cells of 3 cases were all positive for Melan-A,case 2 and case 3 were positive for HMB45,and case 1 and case 2 were positive for S-100. The epithelioid cells of 3 cases were all positive for SMA and CD34. The positive rate of Ki-67 in case1 was approximately 10%,however,case 2 and case 3 was not more than 5%. Conclusions HAML was a rare benign mesenchymal tumor of the liver,and was composed of four tissue components including epithelioid cells,smooth myoid cells,thick-walled vessesl and adipose cells. The epithelioid cells were positive for Melan-A,HMB45 and S-100. HAML could be distinguished from other liver tumors with auxiliary immunohistochemistry.