['We examined the potential impact of alcohol drinking on the incidence of synchronous colorectal cancer.', 'This study comprised 191 men with colorectal cancer who had undergone surgical resection. Synchronous colorectal cancer was found in 16 patients (8.4%). The relationship between synchronous colorectal cancer and alcohol intake was analyzed by multivariate methods. Cumulative alcohol intake was assessed by the drinking index (weekly average multiplied by years of drinking).', 'There was higher incidence of associated adenoma in the synchronous cancer group. Heavy cumulative intake (drinking index 9800 or higher) was associated with significantly higher risk synchronous colorectal cancer than in nondrinkers (odds ratio 6.8). The association of alcohol intake with the risk of synchronous colorectal cancer was not affected by the type of alcohol beverages.'] Does excessive alcohol intake enhance the development of synchronous cancerous lesion in colorectal cancer patients?