Population-based evaluation of disparities in stomach cancer by nativity among Asian and Hispanic populations in California, 2011-2015

BackgroundStomach cancer incidence presents significant racial/ethnic disparities among racial/ethnic minority groups in the United States, particularly among Asian and Hispanic immigrant populations. However, population-based evaluation of disparities by nativity has been scarce because of the lack of nativity-specific population denominators, especially for disaggregated Asian subgroups. Population-based stomach cancer incidence and tumor characteristics by detailed race/ethnicity and nativity were examined.MethodsAnnual age-adjusted incidence rates were calculated by race/ethnicity, sex, and nativity and tumor characteristics, such as stage and anatomic subsite, were evaluated using the 2011-2015 California Cancer Registry data. For Hispanic and Asian populations, nativity-specific population counts were estimated using the US Census and the American Community Survey Public Use Microdata Sample data.ResultsDuring 2011-2015 in California, 14,198 patients were diagnosed with stomach cancer. Annual age-adjusted incidence rates were higher among foreign-born individuals than their US-born counterparts. The difference was modest among Hispanics (similar to 1.3-fold) but larger (similar to 2- to 3-fold) among Chinese, Japanese, and Korean Americans. The highest incidence was observed for foreign-born Korean and Japanese Americans (33 and 33 per 100,000 for men; 15 and 12 per 100,000 for women, respectively). The proportion of localized stage disease was highest among foreign-born Korean Americans (44%); a similar proportion was observed among US-born Korean Americans, although numbers were limited. For other Asians and Hispanics, the localized stage proportion was generally lower among foreign-born than US-born individuals and lowest among foreign-born Japanese Americans (23%).ConclusionsNativity-specific investigation with disaggregated racial/ethnic groups identified substantial stomach cancer disparities among foreign-born immigrant populations. Substantial racial/ethnic disparities in stomach cancer exist in the United States, with the largest disparities found for foreign-born Korean and Japanese Americans. Comparisons of incidence rates and stage distribution underscore the importance of implementing targeted prevention and screening strategies for high-risk racial/ethnic subgroups and immigrant populations in the United States.