S1353 Risk Factors for Gastric Cancer in a Veteran Population

INTRODUCTION: Gastric cancer is one of the most common cancers worldwide, but evidence for screening and surveillance in the US is limited by sparse clinical research. While recent immigrants from endemic regions such as East Asia are known to be at high risk, it’s unclear what are the important risk factors in a population with fewer recent immigrants. Therefore, we conducted a matched case-control study in a VA medical center. METHODS: We identified individuals with gastric cancer using both the tumor registry and electronic medical record at VA New York Harbor from 1/1/97 to 10/31/18. Diagnosis was confirmed by pathology report. Controls were identified from patients who underwent EGD during the same period. Variables of interest included age (at time of data extraction or death), sex, race/ethnicity, H. pylori status, smoking, alcohol use, pernicious anemia, and family history. Controls were matched to cases in a 2:1 ratio by age (+/- 3 years) and sex. Univariable and multivariable conditional logistic regression was performed to evaluate associations between potential risk factors and gastric cancer. RESULTS: A total of 504 patients (168 cases and 336 controls) were identified. The mean age was 76 years and 98% were men (Table 1). Among cancer patients, 40% were diagnosed with Stage IV disease and 80% had non-cardia cancer (Table 2). On univariable analysis, associations between gastric cancer and race/ethnicity, H. pylori status, alcohol use, and pernicious anemia were observed (Table 3). On multivariable analysis, Black individuals had higher risk of gastric cancer than White individuals (OR 2.73, 95% CI 1.12-6.68). Those with H. pylori eradication had lower risk than those who were H. pylori negative (OR 0.15, 95% CI 0.06-0.38). Former alcohol users also had lower risk than never users (OR 0.26, 95% CI 0.07-0.97). CONCLUSION: In a single-center VA study, we found Black race increased risk for gastric cancer, while H. pylori eradication and former alcohol use reduced risk. While prior US-based studies have found increased risk in East Asian and Hispanic populations, our findings suggest Black individuals are at higher risk in a healthcare system with fewer recent immigrants. Further research is required to explore this potential health disparity. That H. pylori eradication and former alcohol use were protective against gastric cancer may indicate greater adherence to medical advice and healthier lifestyles in these individuals.Table 1.: Demographic and Medical CharacteristicsTable 2.: Clinical Characteristics of Gastric Cancer CasesTable 3.: Predictors of Gastric Cancer by Conditional Logistic Regression