Appreciating lifetime risk of gastric cancer through established risk factors is one simple way to promote preventive behavior. We have estimated cumulative risks (CRs) of gastric cancer by genetic and environmental risk factors, PSCA-rs2294008 polymorphism, Helicobacter Pylori (HP) infection and smoking, based on a case-control study involving 697 cases and 1372 controls at Aichi Cancer Center. We estimated odds ratio (OR) and 95% confidence interval (CI) for groups by these factors using logistic regression model after adjustment for age, sex, family history of gastric cancer and intake of fruit and vegetable. The ORs were combined with gastric cancer incidence rates in Japan to calculate CRs using the Peto's method. The CRs by age of 75 varied according to the risk groups, from 0.9% (95% CI, 0.3%-3.3%) for never smokers without both HP infection and risk allele of rs2294008 to 13.4% (95% CI, 13.3%-13.4%) for ever smokers with HP infection and 1-2 risk alleles. Among those with 1-2 risk alleles, the CRs were reduced to 2.0% (95% CI, 1.9%-2.0%) in those without both smoking history and HP infection, 3.9% (95% CI, 3.8%-3.9%) for ever smokers without HP infection, 9.4% (95% CI, 9.4%-9.5%) for never smokers with HP infection, although it was 13.4% in those with both smoking history and HP infection. In conclusion, the findings based on genetic and environmental risk factors in this study would be important information for promoting primary and secondary prevention of gastric cancer.

Citation Format: Hidemi Ito, Isao Oze, Satoyo Hosono, Miki Watanabe, Hideo Tanaka, Keitaro Matsuo. Cumulative risks of gastric cancer by PSCA polymorphism, Helicobacter Pylori infection and smoking history in Japan. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2210. doi:10.1158/1538-7445.AM2014-2210