Diagnostic Pitfall: Parathyroid Carcinoma Expands the Spectrum of Calcitonin and Calcitonin Gene-Related Peptide Expressing Neuroendocrine Neoplasms

Abstract

A 59-year-old man with primary hyperparathyroidism (PTH 76 pmol/L, normal range 2–9 pmol/L) and associated hypercalcemia (3.4 mmol/L, normal range 2.15–2.55 mmol/L) was found to have a CT and Sestamibi scan-localized left thyroid component neckmass. Intraoperatively, the mass was noted to be adherent to the left side of the thyroid and required en bloc resection of the mass with the left lobe. In addition, the patient underwent right hemithyroidectomy for nodular goiter. Postoperatively, the serum PTH level was noted to have significantly dropped (5.6 pmol/L, within normal range), supporting the uniglandular source of hyperparathyroidism.