目的探讨肺动脉内膜肉瘤的临床病理特征及诊断。方法分析肺动脉内膜肉瘤的临床表现及影像学特点,观察分析肺动脉内膜肉瘤的病理形态学及免疫组化染色特点,并复习相关文献。结果 2例患者主要症状为咳嗽、胸闷。CT血管显影(CTA)显示右肺动脉主干狭窄、阻塞。组织学形态,肿瘤以梭形细胞为主,部分呈上皮样细胞,不规则排列,细胞间松散,核分裂象丰富,多形性明显,伴有坏死。免疫组化:2例肿瘤细胞vimentin均(+),其中例2 SMA和ALK灶状(+)。其他分化性标记物均(-)。结论肺动脉内膜肉瘤是一种低分化或未分化的间叶性肿瘤,组织学起源不明,预后差。临床上需要与肺动脉血栓栓塞鉴别。 Objective To investigate the clinicopathological features and diagnosis of pulmonary endartear sarcoma. Methods The clinical manifestations and imaging features of pulmonary endarteosarcoma were analyzed. The pathomorphology and immunohistochemical staining of pulmonary endarteosarcoma were observed and analyzed. Results The main symptoms of 2 patients were cough, chest tightness. CT angiography (CTA) showed a narrowing and obstruction of the trunk of the right pulmonary artery. Histologically, the tumors were mainly spindle cells, some were epithelial-like cells, irregularly arranged, interstitial cells were loose, mitotic figures were abundant, pleomorphism was obvious, accompanied by necrosis. Immunohistochemistry: Two cases of tumor cells vimentin (+), of which 2 cases of SMA and ALK-like (+). Other markers of differentiation (-). Conclusions Pulmonary artery endosarcoma is a poorly differentiated or undifferentiated mesenchymal tumor with histologically unknown origin and poor prognosis. Clinic need to identify with pulmonary thromboembolism.