Changing trends in the incidence of laryngeal cancer.

The incidence of laryngeal cancer during the period 1962-1991 in the Tampere University Hospital area, with a population of 400000, was evaluated. There were 302 (95%) male and 16 (5%) female patients. The mean annual age-adjusted incidence rate was 4.4 per 100000 inhabitants for males and 0.2 for females. The incidence among males decreased significantly from 6.7 to 2.6 over the study period, the most prominent decline being in the age group 40-49 years. No distinct trend was detected in females. The frequency of the disease increased along with age in both sexes. One of the prominent phenomenons was a distinct increase of the glottic to supraglottic incidence ratio from 0.5:1 to 1.9:1 in males.