Hashimoto's thyroiditis: a possible risk factor for lung cancer among Japanese women.

To study the epidemiologic association between Hashimoto's thyroiditis and malignancies, autopsy protocols (1959--1974) were examined at the Tokyo University Hospital. The study cases were classified according to major cause of death, including breast and lung cancer. The relationship between thyroid changes and breast cancer was not significant; however, a significant association between thyroid alteration and lung cancer was identified. This finding suggested that Hashimoto's thyroiditis and related changes could be one of the risk factors for lung cancer among Japanese women.