title: C-cell hyperplasia in thyroid tissue adjacent to follicular cell tumors.
abstract: An immunohistochemical study was conducted on the number and distribution of C-cells in the nonneoplastic thyroid tissue adjacent to tumors of follicular cell origin. It consisted of 49 cases, of which 25 were papillary carcinomas, 22 were follicular adenomas, and 2 were follicular carcinomas. Twenty normal adult thyroids from the Broward's Medical Examiner's morgue served as controls. In 17 of the 49 cases (34.6%), there was a statistically significant increase in the number of C-cells in the normal-appearing thyroid tissue adjacent to follicular cell tumors, with at least 50 C-cells in one low power field, while only one of 20 normal thyroids had a similar number of cells. (P = .02; chi 2 = 5.05). In two tumor cases there were more than 100 C-cells in several low power fields with formation of small C-cell nodules similar to those described in the type II Multiple Endocrine Neoplasia Syndrome (MEN). It was concluded that the nonneoplastic thyroid tissue adjacent to 34.6% of tumors with follicular cell phenotypes contains significantly more C-cells than those present in normal adult thyroids. The possible pathogenesis and clinical significance of these findings are discussed.
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009377:Multiple Endocrine Neoplasia / Q000473:pathology; D013961:Thyroid Gland / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000473:pathology*