Denosumab, an alternative treatment for giant cell tumor of bone

Abstract

Introduction: giant cell tumor of bone (GCTB) is a benign tumor, although it is locally aggressive. It arises mainly in young people at the epi-metaphyseal level. It consists of stromal cells and osteoclasts-like populations, where the RANK-RANKL (receptor activator of nuclear factor kappa-B and its ligand, respectively) stands out. Denosumab, the human monoclonal antibody, acts by specifically inhibiting RANKL, what prevents the formation and activation of multinucleate cells. The existing bibliography indicates denosumab has obtained encouraging results as adjuvant treatment for some GCTB, enabling therapeutic plans that have lower morbi-mortality rates than those applied prior to administration of the antibody.
Method: the study describes the therapeutic experience of two patients younger than 40 years old, who consulted in Uruguay for long standing gonalgia. Campanacci Stage III GCTB was diagnosed, and denosumab treatment was initiated. Clinical response was assessed, as well as imaging response, adverse side effects and the modification of initial treatment.
Results: clinical and imaging response was seen in the assessed patients. No adverse side effects were reported, and the affected joint was preserved.
Conclusions: the results obtained are encouraging with regard to the therapeutic use of denosumab in the selected patients. This allows for denosumab to be regarded within the therapeutic options for certain patients with a diagnosis of GCTB.