ABSTRACT: There have been notable improvements in survival over the past 2 decades for gastrointestinal (GI) cancer. However, the degree of improvement by age, race, and sex remains unclear. We analyzed data from 9 population-based cancer registries included in the SEER program of the National Cancer Institute (SEER 9) in 1990 to 2009 (n = 288,337). The degree of survival improvement over time by age, race, and sex was longitudinally measured. From 1990 to 2009, improvements in survival were greater for younger age groups. For patients aged 20 to 49 years and diagnosed from 2005 to 2009, adjusted HRs (95% CIs) were 0.74 (95% CI, 0.66-0.83), 0.49 (95% CI, 0.37-0.64), 0.69 (95% CI, 0.65-0.76), 0.62 (95% CI, 0.54-0.69), and 0.56 (95% CI, 0.42-0.76), for cancer of the stomach, small intestine, colon, re
