Denosumab (XGEVA®, Amgen, Thousand Oaks, CA, USA), is a fully human monoclonal antibody against receptor activator of nuclear factor-kappa B (RANK) ligand, a key protein secreted by stromal cells and osteoblast in response to growth factors released by tumor cells, which promotes osteoclast activation by binding the RANK-receptor on their surface. The gene discussed is TNFRSF11A; the disease is neoplasm.