ABSTRACT
STUDY DESIGN: A case report. OBJECTIVE: The aim of this study was to highlight that rapid progression or recurrence of giant cell tumor of the bone (GCTB) can still occur with cessation of Denosumab in the management of unresectable GCTB even in cases with prior demonstration of excellent response to treatment and stable disease over a protracted length of surveillance despite dose reduction. The close proximity of unresectable GCTB to vital structures makes it prudent that we monitor these patients closely given its locally aggressive nature. SUMMARY OF BACKGROUND DATA: Cervical spine GCTB is extremely rare. Unresectable GCTB has historically been a challenge to treat due to the lack of prospective, randomized clinical trials to guide treatment. Radiotherapy has fallen out of favor due to the risk of malignant transformation, especially as most GCTB patients are young.In recent years, improved understanding of the receptor activator of nuclear factor-κB ligand (RANKL) in the pathophysiology of GCTB has led to the use of Denosumab in patients with recurrent/unresectable/metastatic GCTB and in patients whom surgical resection carries a high morbidity. To date, the optimal dosage and duration of therapy in the treatment of GCTB is unknown. METHODS: We report a case of cervical spine GCTB in a 53-year-old male with positive surgical margins managed with Denosumab. RESULTS: This is the first reported case of a cervical spine GCTB managed with Denosumab showing excellent response to treatment, recurrence of disease post cessation of Denosumab despite earlier satisfactory disease control and stabilization achieved even with dose reduction, and again an excellent response with recommencement of the drug. CONCLUSION: Denosumab is an excellent option in patients with unresectable GCTB or when surgery will result in excessive morbidity. However, further studies are required to determine optimal dosing, treatment duration, side effect profile, and whether Denosumab is truly able to achieve partial or complete disease remission in the long run. LEVEL OF EVIDENCE: 4.
