Evaluation of risk factors associated with denosumab induced hypocalcemia.

144 Background: Denosumab is a monoclonal antibody that neutralizes RANKL preventing osteoclast activation. It has been shown to be superior to zoledronic acid in preventing skeletal-related events in breast cancer with bone metastases. Hypocalcemia has been reported as a common side effect. The aim is to evaluate the risk factors associated with denosumab induce hypocalcemia. Methods: Retrospective study in which 144 charts were reviewed. Baseline characteristics: age, gender, race, type of cancer, calcium, phosphate, vitamin D, PTH, creatinine levels, GFR and corrected calcium were obtained. Tumors were classified in hormone sensitive versus non-sensitive. Charts were reviewed to evaluate for the development and severity of hypocalcemia as defined by the international review criteria. A multivariant analysis to evaluate the relationship between hypocalcemia and the variables of interest was done. Results: Hypocalcemia was observed in 71 of 144 patients. Grade 2 hypocalcemia was the most common. Signific...