Racial Disparity in Incidence and Survival for Gastrointestinal Stromal Tumors (GISTs): an Analysis of SEER Database

Background Gastrointestinal tumors (GISTs) represent the most common mesenchymal tumors of the gastrointestinal tract. There has been limited data on GIST incidence and survival disparities between ethnic groups. Aims Assess disparities in incidence and survival among race in the USA in the era of available GIST histologic codes and treatment. Methods We queried Surveillance, Epidemiology, and End Results (SEER) database for GIST from 2002 to 2015, with diagnostic code 8936. Results Of the 7204 patients identified, 4928 (68.4%) were White, 1308 (18.2%) African American (AA), and 968 (13.4%) were classified as Other (American Indian/Alaskan Native, Asian/Pacific Islander). The overall incidence rate (IR) was 0.75 per 100,000. IR was highest among AA at 1.37/100,000, but 0.65/100,000 for Whites, 1.10/100,000 for Asians/Pacific Islanders, and 0.28/100,000 for American Indians/Alaskan Natives. The GIST incidence was twice as high for AA as for Whites (rate ratio [RR]: 2.12; 95% CI: 1.98-2.26; p < 0.001). There was higher proportion of Whites than AA, who underwent surgical extirpation. Median overall survival (OS) and GIST specific survival (GSS) were not reached for all race, which indicates more than half of the patients were still alive at end of follow-up period. In multivariate Cox model, belonging to Other had better OS (adjusted hazard ratio [aHR]; 0.73, 95% CI: 0.55-0.95, P = 0.021) for GIST, but no difference in prognosis and OS for AA and White [(aHR for whites; 0.84, 95% CI: 0.69-1.02, P = 0.071), AA = reference]. There was no difference in GSS among races. Conclusions Significant racial disparity in incidence and overall survival for GIST exists, and efforts should be made to bridge this gap and improve outcomes for all races. The overall incidence rate for GIST was noted to be 7.5 per 1 million, and IR of GIST was twice as high for African Americans as compared to Whites. The Other racial group (American Indians/Alaskan Natives, Asians, and Pacific Islanders) had superior OS as compared to African Americans and Whites.