Objective: To investigate the clinicopathological features of primary pulmonary epithelioid hemangioendothelioma (PEHE). Method: Forty cases of PEHE were diagnosed from October 2010 to June 2024 at the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China. A retrospective analysis was conducted on their histological features, imaging findings, immunohistochemical characteristics and molecular phenotypes. Subsequently, the clinicopathological features were summarized. The patients were followed up. Result: Of the 40 cases, there were 19 males and 21 females, age 52.5 (43.0, 62.0) years old. Most patients were admitted for respiratory symptoms, mainly cough (25/40) and expectoration (14/40). Computed tomography findings mainly showed multiple intrapulmonary nodules (33/40) and solitary nodules in 7 cases (7/40). Tumor maximum diameters ranged from 3 to 70 mm, with a median of 19 (12, 35) mm. Grossly, all lesions appeared as grayish-white nodules with ill-defined margins and mucoid cut surfaces. Microscopically, tumor cells showed centrifugal distribution around blood vessels, arranged in irregular nests; local mucoid degeneration and chondroid matrix were noted. Intracytoplasmic vacuoles with red blood cells were noted in some tumor cells, indicating primitive vascular lumen differentiation. At the molecular level, WWTR1-CAMTA1 gene fusion was identified in 36 cases and YAP1-TFE3 fusion in 4 cases. Immunohistochemical results showed diffuse positivity for CD31 (38/38), CD34 (36/40), ERG (40/40) and Fli-1 (40/40), and focal positivity for TFE-3 (4/34). Therapeutic responses of 40 patients were assessed using the Response Evaluation Criteria in Solid Tumors criteria: complete response in 4 cases (10.0%), partial response in 5 (12.5%), stable disease in 7 (17.5%), and progressive disease in 24 (60.0%). Conclusions: PEHE is a rare vascular-derived tumor, radiologically characterized by multiple bilateral pulmonary nodules. It has non-specific clinical manifestations; combined use of highly sensitive and specific endothelial markers and genetic testing helps reach the definitive diagnosis. PEHE has an overall indolent course, with long-term survival in some patients. However, multiple lesions, pleural invasion, and distant metastasis may be linked to worse prognoses.
目的： 探讨原发肺上皮样血管内皮瘤（pulmonary epithelioid hemangioendothelioma，PEHE）的临床病理学特征及预后。 方法： 收集郑州大学第一附属医院2010年10月至2024年6月诊断为PEHE的病例40例，回顾性分析组织形态学特征、影像学、免疫组织化学及分子表型，总结临床病理特征，并随访患者生存情况。 结果： 40例PEHE患者中，男性19例，女性21例，年龄52.5（43.0，62.0）岁。40例患者中多数以咳嗽（25/40）、咳痰（14/40）等呼吸道症状为主要病因入院。CT主要表现为肺内的多发结节（33/40），也可表现为单发结节（7/40），肿瘤最大径19（12，35）mm。大体均表现为灰白色结节，界限不清，切面有黏液感。镜下见肿瘤细胞以血管为中心呈离心性分布，排列成大小不一的巢团状结构，局部区域可见黏液变性及软骨样基质。部分肿瘤细胞内可见含红细胞的空泡，提示原始血管腔分化。36例存在WWTR1-CAMTA1基因融合，4例为YAP1-TFE3基因融合的分子学特征。免疫组织化学结果显示CD31（38/38）、CD34（36/40）、ERG（40/40）及Fli-1（40/40）弥漫阳性，TFE-3（4/34）局灶阳性。40例PEHE患者依实体瘤疗效评价标准RECIST1.1标准评估，其中完全缓解4例（10.0%）、部分缓解5例（12.5%）、疾病稳定7例（17.5%）、疾病进展24例（60.0%）。 结论： PEHE是一种较为罕见的血管源性肿瘤，影像学以双肺多发结节为主要特征，临床表现缺乏特异性，联合应用灵敏度和特异度高的内皮标志物及基因检测有助于诊断。PEHE病程进展相对缓慢，部分患者可长期存活，但肿瘤多发、胸膜侵犯及远处转移可能影响预后。.