The reliability of malignant thyroid tumor diagnosis in the Swedish Cancer Registry. Review of 200 cases.

Two-age stratified periodical samples of 100 cases of malignant thyroid tumors from the Stockholm region and 100 cases other parts of Sweden reported to the Swedish Cancer Registry between 1958 and 1972 were studied. The cytologic and/or histologic slides were re-examined by two pathologists independently. In 85 per cent of the cases reported from Stockholm and in 94 per cent of the cases from other parts of Sweden, the pathologists agreed on the original diagnosis of malignant tumor. The remaining cases (weighted mean 8%) were at re-examination considered to be benign thyroid lesions.