Clinicopathologic and molecular features of denosumab-treated giant cell tumour of bone (GCTB): Analysis of 21 cases

GCTB is an osteolytic, locally-aggressive, rarely-metastasizing tumour, characterized by abundance of osteoclast-like giant cells, induced by neoplastic mononuclear cells expressing high-levels of the receptor activator of nuclear factor Kappa-B ligand (RANKL), a mediator of osteoclast activation. Although the mainstay of treatment is complete tumour removal with preservation of bone, therapy with denosumab, an inhibitor of RANKL, has been introduced for selected cases.