The Role of Surgery for Primary Pulmonary Synovial Sarcoma: A Population-Based Study

Abstract

IntroductionThe rarity of primary pulmonary synovial sarcoma (PPSS) and the lack of prospective clinical trials resulted in poorly understood treatment modality and clinical outcomes. This study aimed to better understand PPSS based on patients from the Surveillance, Epidemiology, and End Results database. Materials and methodsClinical and survival data of PPSS patients who were diagnosed during 1989 through 2016 and retrieved from the Surveillance, Epidemiology, and End Results database were studied. Kaplan–Meier analyses and Cox proportional hazards model were applied to evaluate the overall survival (OS) and disease-specific survival (DSS) of PPSS patients. ResultsA total of 122 patients with PPSS were included (median age: 50 y). PPSS accounted for 4.5% (122/2741) of total primary synovial sarcoma. Most of the patients were diagnosed as poor or undifferentiated grade (52.0% and 34.0%). Cancer-directed surgery was performed for 74.4% of PPSS patients and 28.2% of patients received radiotherapy. The 1-year, 3-year, 5-year, and 10-year OS rates of PPSS patients were 75.4%, 50.8%, 41.8%, and 39.3%, respectively. Cancer-directed surgery was shown to improve the survival of PPSS patients with localized or regional stage (P < 0.05), yet surgical resection did not prolong the OS and DSS of patients with distant stage (P > 0.1). Postoperational radiotherapy was associated with shortened survival time (P < 0.05). PPSS patients who received lobectomy had statistically prolonged OS and DSS than those with pneumonectomy (P < 0.001). ConclusionsPPSS is a rare and special subtype of synovial sarcoma. Treatment with lobectomy or sublobar resection alone may contribute to a superior prognosis compared with other managements.