Relation of bronchioloalveolar carcinoma to tobacco.

OBJECTIVE To determine whether bronchioalveolar carcinoma is related to tobacco use. DESIGN Case-control study. SETTING 11 teaching hospitals of Chicago, Long Island, New York, and Philadelphia, 1977-89. SUBJECTS 87 patients with histologically diagnosed bronchioloalveolar carcinoma (cases) and 286 non-cancer and 297 cancer patients matched to cases on age, sex, race, hospital, and date of admission. RESULTS 10% of male cases and 25% of female cases had never smoked. Relative risks of bronchioloalveolar carcinoma (as estimated by the relative odds) were greater for subjects who started smoking at a younger age, smoked for a longer time, or smoked more cigarettes per day. Relative risks decreased proportionally to the duration of smoking cessation. CONCLUSION Smoking plays an important part in the aetiology of bronchioloalveolar carcinoma but is not the only potential cause because of the large proportion of never smokers among patients with this disease.