We were unable to definitively elucidate the mechanism of hypercalcemia in our case due to the unavailability of PTHrP/CYP27B1 (1-alpha-hydroxylase) immunohistochemical staining and serum assays for PTHrP and 1,25-dihydroxyvitamin D at our institution. This evidence concerns the gene PTHLH and hypercalcemia disease.