Descriptive epidemiology of thyroid cancer in Osaka

Epidemiological aspects of thyroid cancer in cases registered at the Osaka Cancer Registry during 1966-77 were analyzed. Average incidence rate age-adjusted to the world population was 0.6 for males and 1.8 for females. The ratio of incidence to mortality was low in both sex groups over 55 years old. Histologically, papillary adenocarcinoma was most predominant (59%), followed by follicular adenocarcinoma (18%), adenocarcinoma not otherwise specified (12%), and anaplastic carcinoma (7.4%). In the older age groups, the percentage of anaplastic carcinoma was relatively higher than that in the younger groups. Age-specific incidence rates were estimated and 5-year survival rates were calculated for each major histological type.