Endocrine Abstracts

Introduction: Hypercalcitoninemia has frequently been reported as a marker for medullary thyroid carcinoma (MCT). Still, several physiologic and pathologic conditions other than MCT have been associated with increased levels of calcitonin, including neuroendocrine tumors that can ectopically secrete calcitonin.

Case report: We present the case of a 78-year old female patient, incidentally diagnosed with multinodular goiter when performing Doppler ultrasound for the evaluation of severe dizziness. In the last 6 months she was admitted in the emergency room several times with paroxysmal symptoms including fronto-occipital headache, severe hypertension, diaphoresis and anxiety. She had normal thyroid function, but high serum calcitonin, carcinoembryonic antigen (CEA) and chromogranin A levels (210.5 pg/ml, 7.36 ng/ml and 159.1 ng/ml, respectively). The thyroid ultrasound revealed a micronodular goiterwith infracentimetric inflammatory lymph nodes (the largest nodule 0.78/0.83/0.9 cm having a spongiform appearance). The abdominal ultrasound showed left adrenal hyperplasia (20/25/25 mm) and an adrenaladenoma (10/10 mm). The plasmatic metanephrines and normetanephrines were in the normal range, but thedexamethasone suppression test was abnormal (6.01 microg/dl). She underwent unilateral adrenalectomy with a favourable outcome in terms of hypertension control. The histopathology report confirmed adrenocortical nodular hyperplasia. Postoperatively, hypercalcitonemia persisted (196.7 pg/ml) and she had total thyroidectomy with central neck lymph node dissection performed with a significant decrease of serum calcitonin level (46.4 ng/ml) accompanied by CEA normalisation (1.99 ng/ml).

Conclusion: Several types of neuroendocrine tumors, including paragangliomas and pheochromocytomas might be associated with increased levels of calcitonin, but the basal calcitonin values in this conditionsusually varies between 10 and 100 pg/ml. Patients with calcitonin levels > 100 pg/ml have a high risk for MCT (90%–100%) and they should be carrefully evaluated although the symptomatology may point out to a different disorder.