Lung cancer type in relation to cigarette dosage.

In a retrospective study of 1,228 white males with histologically confirmed bronchogenic carcinoma, the proportion of squamous cell carcinoma increased with increasing age at diagnosis. Since the distribution of cell types was much the same in the 73% of cases aged 50-69, the relationship of cancer type to daily cigarette dosage was studied in this group. Squamous cell carcinoma increased from 48% of those men who smoked less than 20 cigarettes per day to 61% of those who smoked 40 or more cigarettes per day. Comparison with other studies showed conflicting results.