THE ORIGIN AND SIGNIFICANCE OF THYROID PSAMMOMA BODIES

  • 1 January 1980
    • journal article
    • research article
    • Vol. 43  (3) , 287-296
Abstract
Ultrastructural techniques were used to study the pathogenesis of calcifications and psammoma bodies in human thyroid disorders. Particular attention was paid to psammoma bodies associated with papillary thyroid carcinoma which represented, the end stages of 2 different biologic events. One event took place in the vascular stalk of the neoplastic papillae, starting with a thickening of the basal lamina followed by vascular thrombosis, calcification and tumor cell necrosis. In the other, intralymphatic tumor thrombi in the thyroid adjacent to the main tumors or in the opposite thyroid lobe became necrotic and calcified. In some instances, destruction of the lymph vessels led to fibrin exudation and perilymphatic fibrosis. The laminated bodies seen inside thyroid follicles in some nonneoplastic conditions represented inspissated colloid and were not considered true psammoma bodies. Like the amyloid calcifications seen in medullary carcinoma and the stromal calcospherites seen in several conditions, they seem to lack diagnostic importance. The biologic importance of the events leading to psammoma body is emphasized formation and how they may contribute to the indolent course of this type of cancer is explained.