Use of denosumab in parathyroid carcinoma with refractory hypercalcemia

### Learning Point for Physicians This case illustrates the difficulties in treating hypercalcemia caused by parathyroid carcinoma. However, there are various choices of treatment and in recalcitrant cases, denosumab should be considered as a therapeutic option. It is important to know the vitamin D status of the patient and to monitor for hypocalcemia post treatment. Parathyroid carcinoma is rare; accounting for ∼1% of all the causes of primary hyperparathyroidism.1 When the tumor is no longer amenable for surgery, medical therapy to control the hypercalcemia becomes the main focus of management. Unfortunately, parathyroid carcinoma mediated hypercalcemia is often severe and more resistant to medical therapy. We report a case of parathyroid carcinoma with refractory hypercalcemia treated with denosumab. A 26-year-old lady with recurrent parathyroid carcinoma initially presented in April 2012 with symptoms of hypercalcemia, a serum calcium of 4.0 mmol/l with …