MANAGING HYPERCALCEMIA OF MALIGNANCY: EVALUATING CALCITONIN DOSAGE AND EFFICACY

BACKGROUND: Hypercalcemia of malignancy is an oncologic emergency that is often treated with hydration, bisphosphonates, and calcitonin. There is a lack of data guiding clinicians on which weight—ideal body weight (IBW) or actual body weight—to use for optimizing efficacy while balancing high acquisition costs.OBJECTIVE: To assess corrected calcium levels 48 hours after the administration of calcitonin using an IBW-based dosing protocol for calcitonin.METHODS: This multicenter, retrospective, pre- and post-quasiexperimental study was conducted in 2 tertiary care hospitals. The restriction criteria in the protocol implemented for calcitonin included corrected calcium ≥12 mg/dL, subcutaneous or intramuscular administration, 4 units/kg per IBW every 12 hours, and a maximum number of 4 doses. Descriptive statistics were performed, followed by the use of Fisher’s exact test, Student’s t-test, and Wilcoxon rank-sum test to compare appropriate data points. An a priori value of <.05 was used to assess statistical significance.RESULTS: A total of 200 orders were included in the analysis, which consisted of 73 preprotocol and 127 postprotocol orders. The mean baseline corrected calcium was similar between both cohorts, at approximately 14 mg/dL. At 48 hours, there was no statistical difference in corrected calcium levels between the preprotocol and postprotocol cohorts (11.4 mg/dL vs 11.3 mg/dL, respectively; P=.86) as well as no difference in the change in corrected calcium from baseline to 48 hours (–2.4 mg/dL vs –2.7 mg/dL, respectively; P=.26). On discharge, the average corrected calcium was 10.6 mg/dL in the preprotocol and postprotocol groups. There was a total cost-savings of $520,700 over 2 years with the use of the restrictive calcitonin protocol.CONCLUSION: The calcitonin dosing protocol using IBW resulted in similar hypercalcemia of malignancy resolution at 48 hours and substantial cost-savings over the 2-year postimplementation period studied.