Efficacy and safety of denosumab treatment in a prepubertal patient with cherubism.

Background: Denosumab is an inhibitor of receptor activator of nuclear factor kappa-B ligand, which strongly suppresses osteoclasts. Cherubism is a rare autosomal dominant disorder characterized by symmetrical swelling of the jaws, in which the bone is replaced by a fibrous granuloma containing osteoclast-like giant cells. Case presentation: We report the efficacy and safety of denosumab treatment in a prepubertal boy with progressive cherubism. The treatment consisting of eight subcutaneous denosumab injections (120 mg/dose) in 6 months not only suppressed the expansion of the osteolytic lesions but also dramatically ossified them. However, a transiently decreased growth rate and rebounded asymptomatic hypercalcemia were associated with the treatment. Conclusions: The present case demonstrated the therapeutic potential of denosumab for treatment of cherubism, although adverse effects, especially those on childhood growth, remain obscure. Further studies are needed to establish a safe and effective protocol for denosumab treatment of children.