目的 探讨原发性肺动脉肉瘤（primary pulmonary artery sarcoma， PPAS）与慢性肺血栓栓塞症（chronic pulmonary thromboembolism， CPTE）的临床表现及CT肺动脉成像（CTPA）特征差异，提高二者的鉴别诊断水平。 方法 回顾性分析经病理确诊的28例PPAS患者及28例CPTE患者的临床资料及CTPA征象，比较两组患者临床症状、实验室指标、CTPA影像特征的差异。 结果 PPAS组男12例，女16例，年龄（50.7 ± 13.6）岁。CPTE组男18例，女10例，年龄（48.7 ± 15.0）岁，两组患者性别、年龄差异无统计学意义（P = 0.108，P = 0.602）。PPAS患者胸痛、咳嗽咳痰发生率及神经元特异性烯醇化酶阳性率显著高于CPTE组（均P 0.05）；CPTE组胸闷、气短、下肢深静脉血栓（deep venous thrombosis， DVT）发生率及N-末端利钠肽前体（N-terminal brain natriuretic peptide precursor， NT-proBNP）阳性率显著高于PPAS组（均P 0.05）；PPAS组病程短于CPTE组［5.5（3.5，9.6）个月 vs. 24.0（9.0，66.0）个月，P 0.001］。PPAS组病变累及主肺动脉、双侧肺动脉干、肺动脉瓣及右室流出道比例明显高于CPTE组，PPAS患者更多表现为完全充盈缺损、病变近心端膨隆、远端动脉瘤样扩张；CPTE组附壁部分充盈缺损为主、病变近心端扁平更常见，其右心室横径/左心室横径比值［（1.06 ± 0.19） vs. （0.93 ± 0.18）］、主肺动脉直径/升主动脉直径比值［（1.20 ± 0.22） vs. （0.85 ± 0.12）］显著高于PPAS组（均P 0.05）。 结论 患者病程短、胸痛咳嗽突出、中央肺动脉内完全充盈缺损、病变近心端膨隆，提示PPAS的可能；而病程长、胸闷气短为主、合并DVT、NT-proBNP升高、附壁部分充盈缺损及右心扩大、主肺动脉增宽，则符合CPTE。充分认识这些差异有助于提高PPAS的早期诊断率，避免误诊误治，为临床鉴别诊断提供初步线索。

Objective To investigate the differences in clinical manifestations and computed tomography pulmonary angiography （CTPA） features between primary pulmonary artery sarcoma （PPAS） and chronic pulmonary thromboembolism （CPTE）， aiming to improve the differential diagnosis of these two conditions. Methods Clinical data and CTPA signs of 28 patients with pathologically confirmed PPAS and 28 patients with CPTE were retrospectively analyzed. The differences in clinical symptoms， laboratory findings， and CTPA features were compared between the two groups. Results In the PPAS group， there were 12 males and 16 females， with a mean age of （50.7 ± 13.6） years. In the CPTE group， there were 18 males and 10 females， with a mean age of （48.7 ± 15.0） years. There were no statistically significant differences in gender and age between the two groups （P = 0.108 for gender， P = 0.602 for age）. The incidences of chest pain and cough with expectoration， along with the positive rate of neuron-specific enolase， were significantly higher in PPAS patients compared to those in the CPTE group （all P 0.05）. The incidences of chest tightness， shortness of breath， lower extremity deep venous thrombosis （DVT）， and the positive rate of N-terminal brain natriuretic peptide precursor （NT-proBNP） in the CPTE group were significantly higher than those in the PPAS group （all P 0.05）. The disease course in the PPAS group was shorter than that in the CPTE group ［5.5 （3.5， 9.6） months vs. 24.0 （9.0， 66.0） months， P 0.001］. The proportions of lesions involving the main pulmonary artery， bilateral pulmonary trunks， pulmonary valve， and right ventricular outflow tract in the PPAS group were significantly higher than those in the CPTE group. PPAS patients more frequently presented with complete filling defects， convex proximal margins， and distal pulmonary artery aneurysmal dilatation. In contrast， the CPTE group predominantly showed mural partial filling defects and flat proximal margins. The ratios of right ventricular diameter to left ventricular diameter and main pulmonary artery diameter to ascending aorta diameter in the CPTE group were significantly higher than those in the PPAS group ［（1.06 ± 0.19） vs. （0.93 ± 0.18） for the right-to-left ventricular diameter ratio， （1.20 ± 0.22） vs. （0.85 ± 0.12） for the main pulmonary artery to ascending aorta diameter ratio； all P 0.05）］. Conclusions The presence of a short disease course， prominent chest pain and cough， and filling defects that occupy the entire lumen of the central pulmonary arteries and exhibit a proximal bulging shape is highly suggestive of PPAS. In contrast， the presence of a long disease course， predominant chest tightness and shortness of breath， complicated DVT， elevated NT-proBNP， mural partial filling defect， and right heart enlargement along with main pulmonary artery dilation may strongly indicate CPTE. Fully recognizing these differences is beneficial for improving the early diagnosis of PPAS， avoiding misdiagnosis and mistreatment， and providing preliminary clues for clinical differential diagnosis.