A Comprehensive Assessment of the Racial and Ethnic Disparities in the Incidence of Gastric Cancer in the United States, 1992-2014

Purpose This study aimed to evaluate the racial and ethnic disparities in the incidence of gastric cancer and their temporal trends in the United States. Materials and Methods Using data from 13 cancer registries in the Surveillance, Epidemiology, and End Results database, we assessed such disparities during 1992-2014 in the United States using a variety of disparity metrics. Results The age-standardized incidence rate of non-cardia gastric cancer was highest in Asian and Pacific Islanders, while the incidence of cardia gastric was highest in non-Hispanic whites in men and was similarly low in all groups in women. The incidence of non-cardia gastric cancer decreased in all groups over time, particularly in Asian and Pacific Islanders (on average by 3% per year). The incidence of cardia gastric remained relatively stable in virtually all racial/ethnic groups. The racial and ethnic disparities in gastric cancer incidence steadily decreased over time as measured on the absolute scale, which was mainly driven by the reduced disparities in non-cardia gastric cancer. The range difference in the incidence of gastric cancer decreased on average by 4.1% per year in men and by 2.6% per year in women from 1992 to 2014. The between group variance decreased by 5.6% per year in men and by 3.4% per year in women. The relative-scale disparity measures generally remained stable over time. Conclusion This study demonstrates decreased racial and ethnic disparities in the incidence of gastric cancer over time in the United States, particularly as measured on the absolute scale.