Immunohistochemical and ultrastructural analysis of medullary carcinoma of the thyroid in relation to hormone production.
Eighteen cases of medullary carcinoma of the thyroid were analyzed immunohistochemically for calcitonin- and ACTH-containing cells, and tumor cells in 8 cases were examined by an electron microscope and analyzed by manual and computer procedures with particular attention paid to the size and quality of secretory granules. Calcitonin- and ACTH-containing cells were found singly or in clusters in 14 and 11 tumors, respectively. In 4 cases, calcitonin-positive cell clusters and an increase in number of singly scattered C cells were seen apart from the main tumor, suggesting a multicentric nature of certain medullary carcinomas. Some ACTH-containing cells were apparently also positive for calcitonin. In a case of familial Sipple disease, follicular lining cells were replaced in areas with ACTH-containing cells. Three to five frequency distribution curves of the size of secretory granules were obtained in all of 6 cases analyzed, and at least two different types of granule matrix were identified.
D000324:Adrenocorticotropic Hormone / Q000378:metabolism*; D000328:Adult; D002116:Calcitonin / Q000378:metabolism*; D002277:Carcinoma / Q000378:metabolism / Q000648:ultrastructure*; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D008297:Male; D008875:Middle Aged; D013964:Thyroid Neoplasms / Q000378:metabolism / Q000648:ultrastructure*
D000324:Adrenocorticotropic Hormone; D002116:Calcitonin