prevalence of hypercalcemia of malignancy among pediatric cancer patients in the uk clinical practice research datalink database

Susan Jick,1 Lin Li,1 Victor M Gastanaga,2 Alexander Liede,2 Rohini K Hernandez2 1Boston Collaborative Drug Surveillance Program, Boston University School of Public Health, Lexington, MA, USA; 2Center for Observational Research, Amgen Inc., Thousand Oaks and South San Francisco, CA, USA Background: The reported proportion of cancer patients who experience hypercalcemia of malignancy (HCM) is low, particularly in the pediatric population, ranging between <1% and 5%. HCM can be observed with any type of tumor in children and occurs most commonly with leukemia. While HCM is a potentially fatal condition, the prevalence of HCM is not well understood in pediatric cancer patients. Methods: Using the UK Clinical Practice Research Datalink, we identified pediatric cancer patients with recorded corrected serum calcium (CSC) from 2003 through 2014. Hypercalcemic patients (CSC ≥10.8 mg/dL) were classified into 4 CSC levels. We estimated the annual prevalence of HCM using Byar’s method. Results: Among 517 pediatric cancer patients, leukemia, lymphoma, and brain tumors were the most frequent cancer types. The prevalence of HCM overall (grade 1 or higher) ranged from 0.24% to 0.81% between 2003 and 2014. There were too few cases to compare prevalence by type of cancer. Conclusion: We provide the first systematic analysis using a UK population-based data source to estimate the number of pediatric cancer patients affected with HCM by grade. Our findings showed that the prevalence of pediatric HCM was very low (0.24%–0.81%) over the 12-year study period, which is consistent with previous study of adult cancer patients in the UK (0.20%–0.67%). Keywords: hypercalcemia, pediatric, cancer, prevalence, Clinical Practice Research Datalink