Hypercalcemia And Metastic Parathyroid Carcinoma: Diagnostic Challenge

Parathyroid carcinoma is an extremely rare neoplasm which typically is associated with hardened nodules in the parathyroid region, hypercalcemia and renal failure. A 69 year-old woman presented with knee pain at an emergency unity. On clinical examination the patient also presented a 2.0cm fibroelastic and mobile node in the left neck, level II. Serum total calcium and parathyroid hormone were increased, and the node was also detected by CT and 99mTc-sestamib scintigraphy. The patient had been surgically previously treated of parathyroid carcinoma misdiagnosed as a thyroid adenoma (eleven years ago), and a hyperplasia of parathyroid chief cells (nine years ago), that after revision was diagnosed as cervical metastasis of parathyroid carcinoma. She was surgically treated by neck dissection, confirming the second regional metastasis of parathyroid carcinoma. The diagnosis of parathyroid carcinoma is a challenge, and although rare, it should be considered in the presence of hypercalcemia and palpable neck nodule.