Dietary Factors and the Risk of Gastric Cancer Among Japanese Women: a Comparison Between the Differentiated and Non-Differentiated Subtypes

PURPOSE: Using data from the Hospital-based Epidemiologic Research Program at Aichi Cancer Center (HERPACC), a case-referent study was performed to clarify whether dietary habits differentially impact on the risk of female gastric cancers of different histological subtypes. METHODS: The study subjects comprised 508 histologically confirmed female gastric cancer cases (156 differentiated, 352 non-differentiated), identified via hospital cancer registry and surgical records between 1988 to 1998. The referents were 36,490 cancer-free first-visit female outpatients over 30 years old presenting at the center within the same period of time. The odds ratios were estimated by logistic regression analyses and adjusted for potential confounding factors. RESULTS: Frequent vegetable and fruit conferred reduced risk of both differentiated and non-differentiated female gastric cancers in similar patterns. In addition, reduced risk was observed for intake of fish and soybean products, particularly for the non-differentiated type. CONCLUSIONS: These results suggest that both differentiated and non-differentiated female gastric cancers are preventable by frequent intake of vegetable and fruit, fish and soybean products, suggested to be common protective factors, although the possibility of some variation in the impact of the diet on different histopathological entities needs to be further addressed.