title: Multiple endocrine cell types in thyroid medullary carcinoma. Evidence for calcitonin, somatostatin, ACTH, 5HT and small granule cells.
abstract: 10 cases of thyroid medullary carcinoma (TMC) have been studied ultrastructurally and histochemically. Well differentiated calcitonin-producing C cells were present in all tumours, being prevalent in 9 cases. 5-Hydroxytryptamine (5HT) storing cells were found in two cases, somatostatin immunoreactive cells in at least 5 cases and ACTH-immunoreactive cells in 4 cases. Ultrastructurally, at least 3 types of apparently non-C cells were observed. Type 1 cells with large, poorly osmiophilic granules resembling those of gastroenteropancreatic D cells, were present in 6 cases; they appeared to correlate well with somatostatin immunoreactive cells. Type 2 cells with large osmiophilic granules were found in 5 cases; they resembled ACTH-MSH cells of the human pituitary and may correspond to the ACTH-immunoreactive cells of light microscopy. Type 3 cells with small granules and an unknown function were found in 6 cases, always in scarce number. It is concluded that TMC, although mainly made up of C cells, usually contains large proportions of other endocrine cell types.
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000032:analysis*; D000328:Adult; D002116:Calcitonin / Q000032:analysis*; D002277:Carcinoma / Q000032:analysis / Q000473:pathology* / Q000648:ultrastructure; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012701:Serotonin / Q000032:analysis*; D013004:Somatostatin / Q000032:analysis*; D013964:Thyroid Neoplasms / Q000032:analysis / Q000473:pathology* / Q000648:ultrastructure
chemical_list: D012701:Serotonin; D013004:Somatostatin; D000324:Adrenocorticotropic Hormone; D002116:Calcitonin