The objective of the present population-based analysis was to assess survival patterns in patients with resected and metastatic GIST.
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.
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 PTrend < 0.05).
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.