Laryngeal keratosis and carcinoma in the Rochester, MN, population 1935-1984.

An attempt was made to identify all laryngeal carcinomas (LSCC), carcinomas in situ (LCIS), and clinical keratoses (LK) in a defined community and to observe them retrospectively via medical records from 1935 to 1984. In Rochester, MN, 108, 7, and 52 cases of LK, LCIS, and LSCC, respectively, were diagnosed, providing mean annual incidence rates of 5.8, 0.4, and 3.3/100,000 person-years. LSCC and LK incidence rates increased more than threefold between 1935 and 1984, while LCIS incidence remained constant. A strong male predilection was noted for all three diseases. The peak age-specific incidence for LK (45 to 54 years of age) occurred a decade earlier than for LSCC. Although 16.2% of LKs had LSCC or LCIS at initial diagnosis over half of LK patients were followed without initial biopsy and only one cancer developed in that group. Clinicopathologic characterization is provided for all three diseases.