摘要目的：探讨肺上皮样血管内皮细胞瘤（ PEH ）的临床病理特点、鉴别诊断及生物学特征。方法总结6例PEH的临床症状、影像学表现，仔细观察病理形态改变以及免疫表型，对患者进行随访。结果 PEH临床症状隐匿，影像学多表现肺部多发小结节。病理镜下表现嗜酸性小结节边界尚清，结节中央区肿瘤细胞稀少、陷在变性间质中不易察觉，周边部肿瘤组织较丰富，凸向肺泡腔内呈“铸型”填充生长。瘤细胞边界不清，细胞异型性小，胞质内见空泡和红细胞，形成原始血管腔。肿瘤细胞表达血管内皮细胞标志物CD31、ERG、CD34及第八因子相关抗原。随访8个月～5年，1例诊断半年后发生骨转移，目前所有患者情况均可。结论 PEH少见，术前难以诊断，病理改变具有一定的特征，但也极易误诊为肺部良性肿瘤或其他恶性肿瘤，需要借助免疫组织化学鉴别诊断。 PEH属于低～中度恶性肿瘤，手术切除为主，可辅以放化疗。

abstractsObjective To investigate the clinicopathologic characteristics, differential diagnosis and prognosis of pulmonary epithelioid hemangioendotheliomas (PEHs).Methods The clinical symptoms and imaging findings of 6 cases of PEHs were investigated and pathologic analyses including histomorphologic and immunohistochemical studies were performed.Results Clinical symptoms of the patients were nonspecific and insidious.The typical radiological manifestation was characterized by multiple small pulmonary nodules. The pathological findings were well-demarcated hypocellular hyalinized nodules with more cellularity at the periphery of the nodule. The neoplastic cells showed mild nuclear atypia and prominent eosinophilic cytoplasm with vacuoles, attempting to form primitive vasculature.Immunohistochemically, tumor cells were positive to CD31, CD34 and ERG.Follow-up data from 8 months to 5 years showed no tumor progression, except for the development of bone metastases in one case at 6 months.Conclusions PEHs are uncommon vascular tumors with low-intermediate malignancy. Using H&E and immunohistochemistry, the final pathological diagnosis can be made and misdiagnosed as a benign fibrotic nodule or other malignant tumors can be avoided. The most effective treatment is surgical resection, if necessary, combined with chemotherapy or radiotherapy.