Pathogenesis and Radiotherapy in Carcinoma of the Thyroid

Abstract

THE pathogenesis of carcinoma of the thyroid differs radically from that of carcinoma in other organs. The progressive pathologic changes in the thyroid gland pass imperceptibly from hyperplasia into simple benign or functional benign neoplasia, and further into malignant neoplasia. Even in a normal thyroid there is a tendency for wide dissemination of thyroid acini, as noted in certain fish, and a general enlargement of the whole organ may take place in the course of normal pregnancy or may be induced by changes in diet or by drugs. At least the endemic prevalence of goiters in certain localities is ascribed to lack of assimilation of iodine. Once such a hyperplasia has taken place it frequently changes in the whole organ or in some parts of it into a true benign neoplasia. Thus, the enlargement of the thyroid in colloid goiter, the most common type, is due to the distention of normal alveoli with colloid, and there is no evidence of any neoplasia. Very frequently, however, in many regions of the goiter,...