Abstract 1735: Fruit and vegetable consumption and risk of gastric cancer: a prospective nested case-control study in China, Japan and Korea
Authors: Wang Tianyi , Cai Hui , Sasazuki Shizuka , Tsugane Shoichiro , Zheng Wei , Cho Eo Rin , Jee Sun Ha , Michel Angelika , Pawlita Michael , Xiang Yong-Bing , Gao Yu-Tang , Shu Xiao-Ou , You Weicheng , Epplein Meira 
Published: July 2016

Abstract
Introduction: Epidemiological findings on the association between fruit and vegetable consumption and gastric cancer risk remain inconsistent, resulting in the designation of fruits and vegetables as “probable” and “possible” respectively, but not “convincing”, protective factors. However, intervention studies provide support for the effect of micronutrient supplementation in the prevention of gastric cancer and its precursor lesions, though the effects remain less substantial than for Helicobacter pylori (H. pylori) eradication. Objective: To ascertain the association between fruit and vegetable intake and non-cardia gastric cancer incidence with adjustment for H. pylori within East Asian cohort studies. Methods: The present analysis includes 1970 participants (810 prospectively ascertained non-cardia gastric cancer cases with 1160 matched controls) from 5 cohort studies in the Helicobacter pylori Biomarker Cohort Consortium. These cohorts collected blood samples as well as demographic, lifestyle, and dietary data at baseline. Pre-diagnostic antibody levels to 15 H. pylori proteins were assessed using multiplex serology. Conditional logistic regression, adjusting for total energy intake, smoking, and H. pylori status, was applied to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for gastric cancer risk across cohort- and sex-specific quartiles of fruit and vegetable intake. Results: Increasing fruit intake was significantly associated with decreasing risk of non-cardia gastric cancer, so that individuals in the highest quartile of fruit consumption had a 29% reduced odds of gastric cancer, compared to individuals in the lowest quartile (OR = 0.71, 95% CI, 0.52-0.95, P for trend = 0.02). Compared to CagA-positive H. pylori low fruit consumers, the strongest inverse association of gastric cancer risk was amongst those high fruit consumers without evidence of H. pylori antibodies (OR = 0.12, 95% CI: 0.06-0.25), whereby the inverse association by increasing fruit consumption was attenuated among individuals infected with CagA-positive H. pylori (OR = 0.82, 95% CI: 0.66-1.03). We observed a weaker, non-dose-response suggestion of an inverse association of vegetable intake with non-cardia gastric cancer risk. Conclusions: To our knowledge, this is the largest prospective study in the high-risk region of East Asia to examine the association of fruit and vegetable consumption with non-cardia gastric cancer risk adjusted for H. pylori. We have found that high fruit intake may play a role in decreasing risk of non-cardia gastric cancer, even after adjustment for H. pylori subtype-specific infection. Funding: R01 CA174853
Citation Format: Tianyi Wang, Hui Cai, Shizuka Sasazuki, Shoichiro Tsugane, Wei Zheng, Eo Rin Cho, Sun Ha Jee, Angelika Michel, Michael Pawlita, Yong-Bing Xiang, Yu-Tang Gao, Xiao-Ou Shu, Weicheng You, Meira Epplein. Fruit and vegetable consumption and risk of gastric cancer: a prospective nested case-control study in China, Japan and Korea. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1735.