Improvement in Overall Survival from Extremity Soft Tissue Sarcoma over Twenty Years

Abstract

Several patient demographic factors, including marital status, have been demonstrated to have prognostic significance for survival in extremity soft tissue sarcoma (ESTS). A study population of 12,546 adult patients diagnosed with ESTS from 1991 to 2010 was identified from the SEER database, a large population-based registry, in order to determine whether overall survival had changed over this recent 20-year period. The study population was divided into three groups by year of diagnosis: 1991-1996, 1997-2003, and 2004-2010. We used the Kaplan-Meier method and Cox proportional hazards regression to assess survival differences between different demographic groups and prognostic clinical characteristics. Over the course of time, the 5-year overall survival rates have increased from 28% in the earliest time period to 62% in the latest (P < 0.0001). On multivariate analysis, the mortality rate progressively declined from the 1991-1996 group (HR: 3.02, CI: 2.78-3.29) to the 1997-2003 group (HR: 2.21, CI: 2.06-2.37), with the 2004-2010 group having the best overall survival, despite increases in the proportion of patients with tumors greater than 5 cm in size (P < 0.0001), and those presenting with metastasis (P < 0.0001).

Figure 1

Kaplan-Meier product-limit curve of overall survival of ESTS from 1991–2010.

Figure 2

Incidence of ESTS in the United States, age-adjusted to the 2000 US Standard Population.