Abstract: Objective: To analyze the etiology and clinical features of occupying lesions of the pulmonary artery trunk. Methods: A retrospective study was conducted in 17 patients with pathologically diagnosed occupying lesions of the pulmonary artery trunk hospitalized at the First Hospital of Guangzhou Medical University from January 2012 to August 2021. Of the 17 patients, 8 were male and 9 were female; their ages ranged from 26 to 70 years, with a mean of (52.1±15.8) years. The etiology was divided into thrombosis (n=5), cancer embolism (n=10), and bacterial embolism (n=2). Of the patients with cancer embolism, 8 were pulmonary artery sarcoma, 1 was pulmonary artery metastasis from choriocarcinoma, and 1 was leukemia with intrapulmonary artery myeloid sarcoma. One case of bacterial embolism and one case of fungal embolism were included in the patients with bacterial embolism. The clinical symptoms, laboratory findings, imaging features, and therapeutic prognosis of the patients were analyzed. Results: Of the 17 patients, the median time interval from first diagnosis to diagnosis was 10.0 (4.0, 12.0) months, and the median time to diagnosis in patients with carcinoma emboli was 11.5 (8.0, 12.0) months. The main symptoms were shortness of breath (94.1%, 16/17), chest pain (82.4%, 14/17), cough (88.2%, 15/17), expectoration (47.1%, 8/17), and hemoptysis (29.4%, 5/17). In patients with cancer thrombosis, platelet count was 274.00 (217.25, 405.00)×10⁹/L, D-dimer was 0.71 (0.51, 0.97) ng/L, and fibrinogen was 6.30 (4.95, 7.72) g/L; in patients with thrombosis, those were 156.00 (126.50, 274.00)×10⁹/L, 1.96 (1.11, 5.02) ng/L and 4.31 (2.43, 6.09) g/L. Abnormal ECG was found in 15 cases, the abnormalities were sinus tachycardia (35.3%, 6/17), T-wave hypoplasia (64.7%, 11/17), and right bundle branch block (35.3%, 6/17). Increased right ventricular load was present on cardiac ultrasound in 11 cases. The estimated PASP was 60.50 (44.00, 98.00) mmHg in patients with cancer embolism and was 49.50 (32.25, 63.75) mmHg in patients with thrombus. The prognosis of 2 patients with bacterial embolism and 3 patients with thrombus were good. Conclusion: Clinicians should pay attention to the etiologic screening of occupying lesions of the pulmonary artery trunk. Elevated platelet counts may be of some value in differentiating carcinoma emboli.

Key words: Pulmonary artery, Pulmonary embolism, Therapies, investigational