Hypocalcaemia following denosumab in prostate cancer: A clinical review

Objectives Denosumab is often used in men with advanced prostate cancer to prevent skeletal‐related events, but can be associated with severe hypocalcaemia. Our objective was to review the pathophysiology, identify risk factors and provide recommendations for prevention and management of denosumab‐associated hypocalcaemia. Design We reviewed the literature regarding denosumab‐associated severe hypocalcaemia, defined as necessitating hospitalization for intravenous calcium treatment, in the context of prostate cancer. Patients Men with prostate cancer with severe denosumab‐associated hypocalcemia. Results We identified 20 men with prostate cancer with severe denosumab‐associated hypocalcemia, including the present case. Median age (range) was 70 years (45‐86). All had skeletal metastases and presented with symptomatic hypocalcemia 16 days (4‐35) after the initial (n = 18) or second (n = 2) denosumab treatment, with a serum total calcium of 1.36 mmol/L (1.13‐1.91). The key risk factor was presence of active osteoblastic metastases, evidenced by elevated serum alkaline phosphatase, 838 U/L (58‐2620) and supportive imaging. Other risk factors reported in some men included vitamin D deficiency (