Population-based SEER trend analysis of overall and cancer-specific survival in 5138 patients with gastrointestinal stromal tumor

Background: The objective of the present population-based analysis was to assess survival patterns in patients with resected and metastatic GIST. Methods: Patients with histologically proven GIST were extracted from the Surveillance, Epidemiology and End Results (SEER) database from 1998 through 2011. Survival was determined applying Kaplan-Meier-estimates and multivariable Cox-regression analyses. The impact of size and mitotic count on survival was assessed with a generalized receiver-operating characteristic-analysis. Results: Overall, 5138 patients were included. Median age was 62 years (range: 18-101 years), 47.3 % were female, 68.8 % Caucasians. GIST location was in the stomach in 58.7 % and small bowel in 31.2 %. Lymph node and distant metastases were found in 5.1 and 18.0 %, respectively. For non-metastatic GIST, three-year overall survival increased from 68.5 % (95 % CI: 58.8-79.8 %) in 1998 to 88.6 % (95 % CI: 85.3-92.0 %) in 2008, cancer-specific survival from 75.3 % (95 % CI: 66.1-85.9 %) in 1998 to 92.2 % (95 % CI: 89.4-95.1 %) in 2008. For metastatic GIST, three-year overall survival increased from 15.0 % (95 % CI: 5.3-42.6 %) in 1998 to 54.7 % (95 % CI: 44.4-67.3 %) in 2008, cancer-specific survival from 15.0 % (95 % CI: 5.3-42.6 %) in 1998 to 61.9 % (95 % CI: 51.4-74.5 %) in 2008 (all P-Trend < 0.05). Conclusions: This is the first SEER trend analysis assessing outcomes in a large cohort of GIST patients over a 11-year time period. The analysis provides compelling evidence of a statistically significant and clinically relevant increase in overall and cancer-specific survival from 1998 to 2008, both for resected as well as metastatic GIST.