[Clinicopathologic analysis of 487 thyroid tumors].

In this paper, 487 cases of thyroid tumor, 387 (79.5%) benign and 100 (20.5%) malignant, were analysed clinicopathologically. Benign thyroid tumor was divided into three types: papillary, follicular and atypical adenomas; malignant thyroid tumor into five types: papillary, follicular, undifferentiated, medullary and squamous cancers. In the benign variety, follicular adenoma had the highest incidence (98.2%) and in the malignant tumors, papillary cancer ranked first (62%). In this series, there were two cases of carcino-sarcoma. The sex ratio of male and female was 1:1.62 for the whole series, 1:1.70 for benign and 1:1.38 for malignant tumors. The peak age was 21 to 40 years with a median of 35 for benign and 31 to 50 years with a median of 43 for malignant tumors. For papillary carcinoma, the patients over 40 years of age comprised 50%. The typing of benign and malignant tumors is discussed. It is proposed that the occult cancer be classified according to histomorphology. Calcitonin by immunohistochemical technic or neural secretory granules by electron microscopy gives the most reliable evidence to diagnosis of the medullary carcinoma.