Introduction: Literature concerning primary pulmonary sarcomas (PPS) is limited to small case series. This study examines, in a large cohort, the clinical characteristics and therapeutic strategies of PPS and their impact on overall survival (OS).
Methods: This was a retrospective analysis from the Surveillance, Epidemiology, and End Results database (1988-2008). Eligible patients had primary PPS and underwent local therapy. Survival estimates were obtained using the Kaplan-Meier method and the Cox regression model. OS of PPS patients were compared with a cohort of 10,909 patients with extremity soft-tissue sarcomas.
Results: The cohort included 365 PPS patients with a median follow-up of 21 months. Fifty-five percent of the patients had large tumors (>5 cm), 76% were high-grade, and 16% had node-positive disease. Seventy-five percent of the cohort underwent surgery alone, 14% underwent surgery and radiation therapy, and 11% underwent radiation therapy alone. Multivariate analysis showed reduced OS for patients with tumors more than 5 cm (hazard ratio [HR] 1.6, 95% confidence interval [CI] 1.25-2.19), high tumor grade (HR 3.1, 95% CI 1.26-3.62), and unresectable disease (HR 2.6, 95% CI 1.76-3.88. The 5-year OS for the cohort of pulmonary sarcomas versus sarcomas of the extremities was 35% versus 71% (p < 0.0001).
Conclusion: This large study examining PPS patients reveals a high rate of nodal involvement and a markedly worse OS than patients with extremity soft-tissue sarcomas. Thus, given the poor overall prognosis, it is recommended that PPS patients undergo a thorough mediastinal nodal evaluation to rule out locoregional metastasis and proceed with aggressive treatment.