Histologic review of breast cancer cases in survivors of atomic bombs in hiroshima and nagasaki, Japan

Abstract

A panel of Japanese and American pathologists reviewed existing histologic material used to study breast cancer risk among the A‐bomb survivors in Hiroshima and Nagasaki, a population in which incidence studies have found a strong relationship between breast cancer risk and radiation dose. The primary charge to the panel was to define a body of confirmed cases in the Life Span Study sample of the Radiation Effects Research Foundation that would require little or no reveiw for inclusion in future studies of breast cancer incidence. Broad agreement on histologic type was reached for 298 of 300 confirmed cases. The distribution of histologic types was, overall, similar to that seen in other studies of breast cancer in Japanese women, and did not appear to depend on dose; thus radiation‐induced breast cancer appeared to be no different histologically from other breast cancer. Also, no evidence was found of variation in histologic type by city, age at exposure, age at diagnosis, or calendar time.