[Tobacco- and alcohol-associated cancer risk of the upper respiratory and digestive tract].

A case-control study of squamous cell carcinoma of the upper aerodigestive tract conducted in the ENT Departments of the University hospitals of Heidelberg and Giessen (FRG) provided information on the role of chronic tobacco and alcohol consumption as risk factors in 200 patients and 800 control subjects (4:1 matched design).--Only 4.5% of the tumour patients were non-smokers in contrast to 29.5% in the control group. The average tobacco and alcohol consumption in the patients was more than twice that high than in the control subjects. The highest alcohol and tobacco consumption was observed in patients suffering from oropharyngeal cancer.--It could be demonstrated that tobacco as well as alcohol increased the risk for head and neck cancer, in a dose-dependent fashion, as separate risk factors. In heavy smokers (greater than 60 pack years) a relative risk of 23.4 (alcohol-adjusted) was calculated. For heavy drinkers (greater than 100 g ethanol/day) a relative risk of 21.4 (tobacco-adjusted) was documented. Combined alcohol and tobacco consumption showed a synergistic effect and increased the cancer risk more in an multiplicative than in an additive manner: A daily ethanol consumption of more than 75 g/day combined with more than 50 pack years caused a risk value of 146.2.