Trends of Incidence and Survival of Gastrointestinal Neuroendocrine Tumors in the United States: A Seer Analysis

OBJECTIVES To examine trends in detection and survival of hollow viscus gastrointestinal neuroendocrine tumors (NETs) across time and geographic regions of the U.S. METHODS We used the Surveillance, Epidemiology and End Results (SEER) database to investigate 19,669 individuals with newly diagnosed gastrointestinal NETs. Trends in incidence were tested using Poisson regression. Cox proportional hazards regression was used to examine survival. RESULTS Incidence increased over time for NETs of all gastrointestinal sites (all P < 0.001), except appendix. Rates have risen faster for NETs of the small intestine and rectum than stomach and colon. Rectal NETs were detected at a faster pace among blacks than whites (P < 0.001) and slower in the East than other regions (P < 0.001). We observed that appendiceal and rectal NETs carry the best prognosis and survival of small intestinal and colon NETs has improved for both men and women. Colon NETs showed different temporal trends in survival according to geographic region (P(interaction) = 0.028). Improved prognosis was more consistent across the country for small intestinal NETs. CONCLUSIONS Incidence of gastrointestinal NETs has increased, accompanied by inconsistently improved survival for different anatomic sites among certain groups defined by race and geographic region.