Primary malignant tumors of the thyroid gland: a clinicopathologic study of 254 cases.

Of 254 primary malignant tumors of the thyroid gland diagnosed in the pathology department of the University of Cape Town, 212 (83.5%) were differentiated carcinomas. In this differentiated group, tumors composed exclusively of papillary structures exhibited the most favorable prognosis; local recurrences and/or spread were noted in tumors with a mixed papillary and follicular pattern and, more commonly association with 21 tumors (8.3%) but an associated multinodular goitre was found in only nine patients (3.5%). In addition to the well-known preponderance of thyroid carcinoma in women, a majority of lesions occurred in white patients in this series despite a higher hospital admission rate for coloreds (mulattos).