Alcohol consumption is associated with an increased risk of distal colon and rectal cancer in Japanese men: The Miyagi Cohort Study

The association between alcohol consumption and the risk of cancer of the proximal or distal colon or rectum remains controversial. We examined this association in a large population-based cohort of Japanese men. In 1990, a self-administered questionnaire on alcohol drinking and other health habits was delivered to 25,279 Japanese men aged 40 to 64 years of age. After exclusion of subjects who gave incomplete responses on alcohol drinking or prevalent cancer cases at the baseline, a total of 21,199 men remained. Of these, 307 men were diagnosed as having colorectal cancer after 11 years of follow-up. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), with adjustments made for potential confounders. Compared with never drinkers, past and current drinkers had multivariate HRs of 1.1 (95% CI, 0.6–1.9) and 1.6 (95% CI, 1.1–2.2) for colorectal cancer, respectively. A dose-response relationship with current volume of alcohol drinkers was observed for cancer of the distal colon and rectum, but not for proximal colon. The multivariate HRs for distal colon and rectal cancer among current heavy drinkers (45.6 g or more ethanol per day) as compared with never drinkers were 4.2 (1.6–10.7; p for trend =  0.0002) and 1.8 (1.1–3.2; p for trend =  0.04), respectively. In contrast, no significant linear association was found for proximal colon cancer (p for trend =  0.2). These data indicate that alcohol consumption in Japanese men is associated with a statistically significant increased risk of cancer of the distal colon and rectum, but not cancer of the proximal colon.