Dietary Fish and n-3 Polyunsaturated Fatty Acid Consumption, and Renal Cell Carcinoma Risk in Japan: The Japan Public Health Center-Based Prospective Study

Previous epidemiologic studies found inconsistent associations between fish consumption and renal cell carcinoma (RCC). Although the consumption of n-3 polyunsaturated fatty acids (PUFA) was reported to protect against the development of some types of cancer, little is known regarding its association with RCC.

We investigated the association between fish and n-3 PUFA consumption and RCC risk using the Japan Public Health Center-based Prospective Study. We examined data from 84,063 eligible Japanese participants aged 45 to 74 years who responded to a validated food frequency questionnaire for Cohort I in 1995 and Cohort II in 1998. The participants were followed-up until 2013. HRs and 95% confidence intervals (CI) were estimated using a multivariable-adjusted Cox proportional hazard model, and the exposure level was categorized into quartiles.

Among the 1,272,298 person-years of follow-up, 262 cases of newly diagnosed RCC were identified. The multivariate-adjusted HRs for the highest vs. lowest quartile of fish, including shellfish, were (HR = 1.43; 95% CI, 0.98–2.07) and the individual marine n-3 PUFAs were (HR = 1.56; 95% CI, 1.07–2.28; P_trend = 0.09) for eicosapentenoic acid, (HR = 1.81; 95% CI, 1.27–2.59; P_trend = 0.01) for docosapentaenoic acid, and (HR = 1.56; 95% CI, 1.07–2.27; P_trend = 0.09) for docosahexaenoic acid. RCC were further categorized on the basis of diagnosis methods and cancer stage, and the positive correlation did not change substantially.

We demonstrated that high consumption of n-3 PUFA is associated with RCC risk.

The positive association between n-3 PUFA and RCC risk was observed in Japanese who consume higher amounts of fish than Western populations.