Abstract
BACKGROUND: Gastric cancer disproportionately affects Latinos, but little is known about regional effects and risk factors. We compared primary incidence, late-stage diagnosis, and risk factors for gastric adenocarcinoma (GCA) from 2004 to 2016 in Latinos and non-Latinos in the United States, Texas (TX), and South Texas (STX). METHODS: We collected case data from Surveillance, Epidemiology, and End Results (SEER) and the Texas Cancer Registry. We generated average annual age-adjusted incidence rates, rate ratios (RRs), and 95% confidence intervals (CIs) using SEER*Stat software and analyzed the cases by anatomic site, demographics, and county-level risk factors using SAS 9.4. We constructed multilevel logistic regression models for late-stage GCA, adjusting for patient- and county-level characteristics. RESULTS: Latinos had higher overall GCA incidence rates in all regions, with the greatest disparities in overlap GCA in STX males (RR 4.39; 95% CI: 2.85, 6.93). There were no differences in cardia GCA rates for non-Hispanic Whites (NHWs) and Latino women in all regions. Younger patients, patients with overlapping or not otherwise specified (NOS) lesions, and patients diagnosed during 2012-2016 had higher odds of late-stage GCA. The stratification by location showed no differences in late-stage disease between NHWs and Latinos. The stratification by anatomic site showed Latinos with cardia GCA were more likely to have late-stage GCA than NHWs (OR: 1.13, p = 0.008). At the county level, higher odds of late-stage GCA were associated with medium and high social deprivation levels in TX without STX (OR: 1.25 and 1.20, p = 0.007 and 0.028, respectively), and medium social deprivation index (SDI) in patients with NOS GCA (OR: 1.21, p = 0.01). CONCLUSIONS: STX Latinos experience greater GCA disparities than those in TX and the United States. Younger age and social deprivation increase the risk for late-stage GCA, while Latinos and women are at higher risk specifically for late-stage cardia GCA. There is a need for population-specific, culturally responsive intervention and prevention measures, and additional research to elucidate contributing risk factors.