title: C-cell hyperplasia developing in residual thyroid following resection for sporadic medullary carcinoma.
abstract: Four days following resection of a medullary carcinoma of the thyroid, a 49-year-old man experienced elevated serum calcitonin levels. There was no evidence of metastasis. A re-exploration of the patient's neck demonstrated a histologically normal thyroid remnant that demonstrated C-cell hyperplasia by immunoperoxidase staining. The lack of a familial history, a normal parathyroid, and the absence of C-cell hyperplasia in non-tumorous thyroid of the original resection support the concept that the patient had a sporadic tumor. Patients who had undergone incomplete thyroidectomies for non-familial disease are at risk for developing C-cell proliferation and possibly medullary carcinoma. We conclude that the C-cell hyperplasia in this thyroid remnant is the source of the elevated calcitonin level; this mechanism may also explain postoperatively elevated calcitonin levels in some patients with medullary carcinoma treated by partial thyroidectomy and high calcitonin levels for a variable period after complete thyroidectomy.
mesh_terms: D000328:Adult; D002116:Calcitonin / Q000494:pharmacology*; D002277:Carcinoma / Q000150:complications* / Q000601:surgery; D006801:Humans; D006965:Hyperplasia / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D008297:Male; D012306:Risk; D013959:Thyroid Diseases / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D013964:Thyroid Neoplasms / Q000150:complications* / Q000601:surgery; D013965:Thyroidectomy
chemical_list: D002116:Calcitonin