title: Calcitonin concentrations in patients with chronic kidney disease and medullary thyroid carcinoma or c-cell hyperplasia.
abstract: It is currently not known which level of pentagastrin-stimulated calcitonin serum concentration indicates medullary thyroid carcinoma in patients with chronic kidney disease (CKD). We examined CKD stage 3-5 patients who had total thyroidectomy because of a pentagastrin-stimulated calcitonin concentration greater than 100 pg/ml, and tested the diagnostic performance of basal and pentagastrin-stimulated calcitonin levels for differentiating medullary thyroid carcinoma and C-cell hyperplasia in this patient population. A total of 180 CKD patients presented with an elevated calcitonin level and had a pentagastrin stimulation test. Forty patients showed a maximum pentagastrin-stimulated calcitonin concentration greater than 100 pg/ml, and 22 patients had a total thyroidectomy. Seven of these 22 patients presented with a medullary thyroid carcinoma, all other patients showed C-cell hyperplasia. Patients with medullary thyroid carcinoma showed higher unstimulated (212 pg/ml (36-577) vs 42 pg/ml (17-150); P < 0.001) and higher maximum pentagastrin-stimulated calcitonin concentrations (862 pg/ml (431-2423) vs 141 pg/ml (102-471); P < 0.001) as compared to patients with C-cell hyperplasia. The sensitivity (100%) and specificity (93%) estimates suggested that a maximum pentagastrin-stimulated calcitonin concentration greater than 400 pg/ml indicates the presence of medullary thyroid carcinoma in patients with CKD. Receiver-operating characteristic (ROC) analysis revealed an area under the ROC plot of 0.99 for maximum pentagastrin-stimulated calcitonin concentrations. A maximum pentagastrin-stimulated calcitonin concentration greater than 400 pg/ml appears to be a clinically meaningful threshold for thyroidectomy.
authors.affiliation: Department of Medicine III, Division of Nephrology and Dialysis, Medical University Vienna, Vienna, Austria. kyra.borchhardt@meduniwien.ac.at
authors.forename: K A
authors.initials: KA
authors.lastname: Borchhardt
authors.forename: H
authors.initials: H
authors.lastname: Heinzl
authors.forename: A
authors.initials: A
authors.lastname: Gessl
authors.forename: W H
authors.initials: WH
authors.lastname: Hörl
authors.forename: K
authors.initials: K
authors.lastname: Kaserer
authors.forename: G
authors.initials: G
authors.lastname: Sunder-Plassmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002116:Calcitonin / Q000097:blood*; D018276:Carcinoma, Medullary / Q000175:diagnosis*; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D010418:Pentagastrin; D012372:ROC Curve; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000378:metabolism*; D013961:Thyroid Gland / Q000473:pathology* / Q000601:surgery; D013964:Thyroid Neoplasms / Q000175:diagnosis*; D013965:Thyroidectomy
chemical_list: D002116:Calcitonin; D010418:Pentagastrin