Fan Chuifeng, Yang Lianhe, Lin Xuyong, Wang Enhua
Department of Pathology, First Affiliated Hospital and College of Basic Medical Sciences of China Medical University, 110001, Shenyang, China.
Institute of Pathology and Pathophysiology, China Medical University, 110001, Shenyang, China.
Diagn Pathol. 2015 Aug 28;10:150. doi: 10.1186/s13000-015-0384-z.
Pseudomyogenic hemangioendothelioma is an extremely rare soft tissue tumor, also named as epithelioid sarcoma-like hemangioendothelioma, which occurs more frequently in young adult males. It was originally recognized as a variant of epitheloid sarcoma, however it is now concluded as a distinctive, rarely metastasizing endothelial neoplasm. We present a case of pseudomyogenic hemangioendothelioma in the lower limb in a 49-year-old female who has a long course of disease and suffered from twice local recurrences and lymph node affection of the tumor. The mass was subcutaneous and the margins were ill-defined. Morphologically, the tumor cells show diversity, composed of large spindle cells and round cells, both with abundant eocinophilic cytoplasm, mimicking rhybdomyoplasts and epitheloid cells respectively. The tumor cells show diffuse strong expression of Factor VIII, Fli-1, INI-1, vimentin, MDM2, and CDK4, local expression of CD31, AE1/AE3, EMA and P63, and no expression of CD34, S-100, actin-sm, desmin, MyoD1, and HMB45. Based on these information, this case is diagnosed as pseudomyogenic hemangioendothelioma after ruling out the main differential diagnosises including epithelioid sarcoma, malignant peripheral nerve sheath tumor and rhabdomyosarcoma. From this case we suggest that pseudomyogenic hemangioendothelioma may be confused with a variety of soft tissue neoplasm histologically. The clinical feature of the case of a long course of disease with twice local recurrences and final lymph node involvement 10 years after excision of the primary tumor indicates a relative indolent behavior of this tumor.
假肌源性血管内皮瘤是一种极其罕见的软组织肿瘤，也被称为上皮样肉瘤样血管内皮瘤，在年轻成年男性中更为常见。它最初被认为是上皮样肉瘤的一种变体，但现在被认定为一种独特的、很少发生转移的内皮肿瘤。我们报告一例49岁女性下肢假肌源性血管内皮瘤病例，该患者病程较长，肿瘤出现两次局部复发并伴有淋巴结受累。肿块位于皮下，边界不清。形态学上，肿瘤细胞表现多样，由大梭形细胞和圆形细胞组成，两者均具有丰富的嗜酸性细胞质，分别模仿横纹肌样细胞和上皮样细胞。肿瘤细胞显示因子VIII、Fli-1、INI-1、波形蛋白、MDM2和CDK4弥漫性强表达，CD31、AE1/AE3、EMA和P63局部表达，而CD34、S-100、肌动蛋白-sm、结蛋白、MyoD1和HMB45不表达。基于这些信息，在排除主要鉴别诊断（包括上皮样肉瘤、恶性外周神经鞘瘤和横纹肌肉瘤）后，该病例被诊断为假肌源性血管内皮瘤。从该病例我们认为，假肌源性血管内皮瘤在组织学上可能与多种软组织肿瘤混淆。该病例病程较长，局部复发两次，原发肿瘤切除10年后最终出现淋巴结受累，其临床特征表明该肿瘤具有相对惰性的行为。
