Clinical characteristics of primary pulmonary hemangiosarcoma outcomes: a Surveillance, Epidemiology, and End Results database analysis.

Primary pulmonary hemangiosarcoma (PPHS) is an extraordinarily rare disorder. The objective of this study was to investigate the demographic characteristics and prognostic factors of patients with PPHS. Patients diagnosed with PPHS between 2000 and 2020 based on data from the Surveillance, Epidemiology, and End Results (SEER) database were retrospectively analyzed. Survival analysis was performed using the survival package of R (4.2.0). Univariate and multivariate Cox proportional hazards models were used to analyze independent prognostic factors. A nomogram was constructed by the R Regression Modeling Strategies (rms) package. A total of 123 patients with PPHS were included in this study; their mean survival time was 13.8 months. Further investigation revealed that the disease-specific survival rates of patients with PPHS at 1, 2, 3, and 5 years were 20.17%, 14.29%, 10.08%, and 5.88% respectively. In the regression analysis, age, tumor status, and treatment were identified as risk factors for patients with PPHS. In addition, chemotherapy was crucial for the treatment of patients with PPHS (P < 0.05). Finally, the nomogram we constructed to predict 0.5-, 1-, 2-, and 3-year disease-specific survival in patients with PPHS showed good accuracy (concordance index: 0.769). Age, tumor laterality, and tumor size were independent factors affecting the prognosis of patients with PPHS, and chemotherapy may significantly improve the long-term prognosis.