Metastatic parathyroid cancer: a rare cause of hypercalcaemia.

A 45-year-old man presenting with abdominal pain was found to have severe hypercalcaemia with elevated parathyroid hormone. Investigations revealed a parathyroid mass and bone metastases consistent with metastatic parathyroid carcinoma. The patient underwent parathyroidectomy, with histology confirming a right inferior parathyroid carcinoma. His postoperative management was complicated by severe hypercalcaemia refractory to medical therapy, owing to the metastases continuing to produce parathyroid hormone. Despite palliative radiotherapy to the metastases, the patient died within 3 months from end-organ failure related to hypercalcaemia.