Pseudomyogenic hemangioendothelioma (PHE) is a rare angiogenic tumor. Histologically, the morphological characteristics of neoplastic vessels and endothelial differentiation are not obvious, and it is easy to be confused with epithelioid sarcoma, epithelioid hemangioendothelioma and myogenic tumor. PHE usually occurs in arms and legs in young people and has a significant male predominance. The tumor has a predilection for the distal extremities and its typical manifestation is multiple center invasion of a single limb, which can involve all layers of skin and subcutaneous tissues,and is often accompanied by abvious pain. Histologically, PHE is characterized by infiltrative growth of tumor. Most tumor lesions are composed of sheets and loose fascicles of plump spindle or epithelioid cells within a background of variably prominent inflammatory infiltration, which was commonly composed of neutrophils. Some cells may resemble rhabdomyoblasts, and nuclear atypia and mitosis were rare. The tumor cells generally expressed positive cytokeratin (CK), ETS-related gene (ERG), Friend leukemia virus integration 1 (FLI1) and integrase interactor 1(INI1). In some cases, the tumor cells expressed CD31. A case of a young woman was reported in this paper, who presented with a subcutaneous mass with severe pain and was chronologically misdiagnosed with herpes zoster, low-grade malignant fibrous histiocytoma and epithelioid hemangioendothelioma. In this study, the clinical and pathological features, differential diagnosis and the latest progress in therapy of PHE were analyzed based on relevant literature.
假肌源性血管内皮瘤(pseudomyogenic hemangioendothelioma，PHE)是一种十分罕见的血管源性肿瘤，组织学上肿瘤性血管和内皮分化的形态特征皆不明显，易与上皮样肉瘤、上皮样血管内皮细胞瘤或肌源性肿瘤相混淆。PHE好发于青年男性，多见于四肢，典型表现为单个肢体多个中心侵犯，可累及皮肤及皮下组织各层，常伴有显著的疼痛。PHE组织病理特点为肿瘤呈浸润性生长，肿瘤细胞主要由疏松的呈束状或片状分布的梭形细胞组成，形态上可出现横纹肌母细胞样或上皮样细胞，可伴有炎症细胞浸润，以中性粒细胞多见，核异型及核分裂像少见。肿瘤细胞常阳性表达细胞角蛋白(cytokeratin，CK)、ETS相关基因(ETS-related gene，ERG)、Friend白血病病毒整合基因(Friend leukemia virus integration 1，FLI1)和整合酶相互作用分子1(integrase interactor 1，INI1)，部分患者阳性表达CD31。1例青年女性因发现皮下肿块伴剧烈疼痛就诊，先后被误诊为带状疱疹、低度恶性纤维组织细胞瘤和上皮样血管内皮细胞瘤。本文结合相关文献分析PHE的临床及病理学特征、鉴别诊断及最新的治疗进展。.
Keywords: epithelioid hemangioendothelioma; epithelioid sarcoma; low-grade malignant fibrous histiocytoma; peudomyogenic hemangioendothelioma.