目的·探索上皮样血管内皮瘤（epithelioid hemangioendothelioma，EHE）患者的临床、病理及分子遗传学特征及其预后。方法·收集2016年9月至2023年12月上海交通大学医学院附属仁济医院确诊的12例EHE患者的临床及随访资料，组织样本分别行苏木精-伊红（hematoxylin-eosin，H-E）染色、免疫组织化学（immunohistochemistry，IHC）染色和荧光原位杂交（fluorescence in situ hybridization，FISH）检测。结果·12例患者中男性患者3名、女性9名，平均年龄（47.17±11.15）岁；肿瘤分布为肝脏6例、肺4例、纵隔1例、右锁骨上1例；无症状患者9例，其余3例患者因胸闷、乏力等轻微不适症状就医。CT检查显示发生在肝脏和肺部的EHE患者均为多发结节，其中2例同时累及肝脏和肺；发生在锁骨上及纵隔的EHE患者为单发结节。H-E染色显示：肿瘤组织由上皮样细胞、树突状细胞和中间细胞构成，排列呈腺泡状、条索状或簇状；上皮样细胞具有圆形泡状核及嗜酸性胞质，部分细胞呈印戒样外观伴胞质空泡；间质含黏液样基质。IHC染色显示：肿瘤组织的间叶源性血管内皮标志物波形蛋白、CD31、ETS转录因子ERG、凝血第Ⅷ因子相关抗原均为阳性，而上皮源性标志物阳性率低且仅呈弱阳性，Ki-67指数也较低。FISH检测显示：10例患者存在钙调素结合转录激活因子1（calmodulin-binding transcription activator 1，CAMTA1）基因断裂，另2例患者存在转录因子E3（transcription factor E3，TFE3）基因断裂。12例患者中11例获得随访结果，随访时间2~38个月，平均21.7个月，其中3例无瘤生存，6例带瘤生存，1例术后4个月死亡，1例术后24个月因心脏病死亡。结论·EHE临床特征不典型、易复发、预后差异较大；组织病理学结合IHC及分子检测有助于明确诊断。

Objective ·To investigate the clinical, pathological, and molecular genetic features and prognosis of epithelioid hemangioendothelioma (EHE) patients. Methods ·Clinical and follow-up data of 12 EHE patients diagnosed at Renji Hospital, Shanghai Jiao Tong University School of Medicine from September 2016 to December 2023 were collected. Tissue samples were analyzed using hematoxylin-eosin (H-E) staining, immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH). Results ·Among the 12 patients, there were 3 males and 9 females, with a mean age of (47.17±11.15) years. Tumors were located in the liver (6 cases), lung (4 cases), mediastinum (1 case), and supraclavicular region (1 case). Nine patients were asymptomatic, while 3 presented with mild symptoms such as chest tightness and fatigue. CT imaging revealed that EHE patients with involvement of livers and lungs exhibited multiple nodules, and 2 cases had tumors in both organs. Patients with tumors in the supraclavicular region and mediastinum presented with solitary nodules. H-E staining demonstrated that tumor tissues were composed of epithelioid, dendritic, and intermediate cells, arranged in acinar, cord-like, or clustered patterns. Epithelioid cells had round vesicular nuclei and eosinophilic cytoplasm, with some showing a signet-ring appearance and cytoplasmic vacuoles. The stroma contained a mucoid matrix. IHC staining revealed that mesenchymal endothelial markers, including vimentin, CD31, ETS transcription factor ERG, and factor Ⅷ-related antigen, were positive in the tumor tissues, while epithelial markers showed low positivity with weak staining. The Ki-67 indexes were also low. FISH analysis showed that 10 patients had a calmodulin-binding transcription activator 1 (CAMTA1) gene break, while 2 patients had a transcription factor E3 (TFE3) gene break. Of the 12 patients, 11 were followed up for 2 to 38 months, with a mean follow-up time of 21.7 months. Three patients achieved tumor-free survival, 6 were alive with tumors, 1 died 4 months after surgery, and 1 died of heart disease 24 months after surgery. Conclusion ·EHE has atypical clinical features, a tendency to recur, a and variable prognosis. Accurate diagnosis requires a combination of histopathology, IHC, and a molecular testing.