AIMS: The aim of this study was to compare the cancer morbidity in a large cohort of patients with alcohol use disorders in the general Danish population. METHODS: We included 15,258 men and 3552 women free of cancer when attending the Copenhagen Outpatient Clinic for Alcoholics in the period from 1954 to 1992. The cancer incidence until 1999 of the patients and the general Danish population was obtained through linkage with the Danish Cancer Registry. The incidence rates were standardized (SIR) according to sex, age and calendar time. RESULTS: A total of 2145 men developed cancer compared to 1140.8 expected cases (SIR = 1.9; 95% confidence interval (CI) 1.8-2.0), while 601 women developed cancer compared to 239.1 expected cases (SIR = 2.5; 95% CI 2.3-2.7). Highly significant and strongly elevated incidence rates were found for cancer of the tongue, mouth, pharynx, oesophagus, liver, larynx and lung. A higher incidence rate was seen for renal cancer for both men (1.4; 1.1-1.8) and women (2.1; 1.0-3.8). The incidence of breast cancer in women was non-significantly elevated, but significantly elevated incidence rate was found for cervical cancer (1.8; 1.2-2.6). We did not observe increased incidence of colon, rectal or urinary bladder cancer. CONCLUSIONS: In conclusion, this study confirms the well-established association between high alcohol intake and cancer of the upper digestive tract and liver. In addition, the results indicate a significantly elevated occurrence of renal cancer, but not of breast cancer and colorectal cancer, in patients with alcohol use disorders.