Progressive Improvement in 5-Year Survival Rates for Extremity Soft Tissue Sarcomas from 1999 to 2019.

Background: Extremity soft-tissue sarcoma (ESTS) is a group of rare, heterogeneous malignancies. Previous studies have demonstrated a progressive improvement in 5-year survival rate over time, but recent trends are unknown. Therefore, this study aimed to provide an update on the clinical characteristics and 5-year survival rate of ESTS from 1999 to 2019. Methods: This retrospective cohort study used the Surveillance, Epidemiology, and End Results (SEER) database. Overall, 5,654 patients over the age of 15 years with primary ESTS diagnosed between 1999 and 2019 were included. Data on patient demographics, clinical characteristics, and survival were extracted. Patients were grouped by year of diagnosis: 1999-2005, 2006-2012, and 2013-2019. Kaplan-Meier and Cox proportional hazards regression analyses were performed. Results: ESTS occurred primarily in the lower extremity (76.1%) and was frequently grade III (58.3%), >5 cm in size (69.9%), and without metastasis (77.9%) at diagnosis. Furthermore, there was a significant increase in the proportion of patients over age 60 ( Conclusions: The 5-year overall survival rate for ESTS progressively improved over the 20-year study period, perhaps due to an increasing proportion of older patients diagnosed with local disease. These findings may also be related to earlier detection or more effective treatment over the study period.