It is caused by bone osteolysis due to metastases (20% of cases), paraneoplastic secretion of parathyroid hormone-related protein (PTHrP) (80%), configuring a humoral hypercalcaemia of malignancy (HHM), and rarely by ectopic parathyroid hormone (PTH) (<1%) or 1,25-dihydroxyvitamin D secretion (<1%) (1). This evidence concerns the gene PTH and Hypercalcemia.