ORIGINAL ARTICLE BENEFIT OF MEASURING BASAL SERUM CALCITONIN TO DETECT MEDULLARY THYROID CARCINOMA IN A DANISH POPULATION WITH A HIGH PREVALENCE OF THYROID NODULES Martin Hasselgren, MD, 1 Laszlo Hegedu ¨ s, MD, DMSc, 1 Christian Godballe, MD, PhD, 2 Steen Joop Bonnema, MD, PhD 1 1 Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark. E-mail: steen.bonnema@dadlnet.dk 2 Department of Oto-Rhino-Laryngology, Odense University Hospital, Odense, Denmark Accepted 23 June 2009 Published online 18 August 2009 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/hed.21228 Abstract: Background. Routine measurement of serum cal- citonin to detect medullary thyroid carcinoma (MTC) continues to be fiercely debated, although less attention has been paid to the positive predictive value (PPV) of this method. Methods. We collected data from 959 patients with non- toxic nodular goiter; thyroidectomy was performed in 307 of these patients. Results. Thirty-nine patients had elevated serum calcitonin; 6 of these patients had MTC detected by the initial diagnostic setup. No additional patient in the cohort was registered in the Danish Thyroid Cancer Database, reflecting that all patients with MTC were classified correctly initially. The sensitivity of se- rum calcitonin for detection of MTC was 100%, the specificity was 95.3%, the positive predictive value was 15.4%, and the negative predictive value was 100%. Conclusion. Serum calcitonin has high sensitivity and spec- ificity for detection of MTC. The low PPV might lead to unnecessary thyroid surgery. Thus, the result of serum calcito- nin measurement should always be interpreted in the context of other clinical variables. V V C 2009 Wiley Periodicals, Inc. Head Neck 32: 612–618, 2010 Keywords: calcitonin; medullary thyroid carcinoma; nodular goiter; sensitivity; screening Medullary thyroid carcinoma (MTC), accounting for 5% to 10% of all thyroid malignancies, 1–3 is derived from the calcitonin secreting parafollicu- lar C-cells of the thyroid. MTC has a rather poor prognosis, which in turn is intimately related to the stage of the tumor. 4–8 Hence, early detection of MTC among patients with nodular goiter is of obvious importance for the prognosis. MTC is ei- ther sporadic (75%) or hereditary (25%). 1,6,9 The better prognosis of the latter is attributed to early genetic screening of the RET (‘‘rearranged during transfection’’) proto-oncogene involved, enabling timely detection of MTC and subse- quent early thyroidectomy. 3,5,8 Routine measurement of basal serum serum calcitonin in the investigation of nontoxic thy- roid nodular disease has been investigated and Correspondence to: S. J. Bonnema This study has been accepted for presentation at the 34th Annual Meet- ing of the European Thyroid Association, September 5–9, 2009, Lisbon, Portugal. V V C 2009 Wiley Periodicals, Inc. 612 Calcitonin and Nodular Goiter HEAD & NECK—DOI 10.1002/hed May 2010