Occult thyroid carcinoma in olmsted county, minnesota: Prevalence at autopsy compared with that in hiroshima and nagasaki. Japan

Abstract

Nine occult carcinomas of the thyroid were found in 157 autopsies of deceased residents of Olmsted County, Minnesota, a prevalence of 5.7%. This rate is significantly lower than that reported from a previous autopsy series from Hiroshima-Nagasaki, Japan, in which similar pathologic methods and diagnostic criteria were used. Sex ratio, age distribution, and radiation exposure are considered not to explain this difference. A true difference between the Japanese and American populations with respect to the prevalence of occult thyroid carcinoma is the most likely explanation of these findings.