Giant Cell Tumor of the Cervical Axis Treated With Anterior-Posterior Surgery and Denosumab: A Ten-year Follow-up Case Report

<h3>Background/Aim:</h3> Giant cell tumor of the bone (GCTB) is a benign but locally aggressive neoplasm that rarely involves the cervical spine, accounting for approximately 1-4% of all primary bone tumors. The cervical axis (C2) is an exceptionally rare site, presenting unique surgical challenges due to its complex anatomy and proximity to vital neurovascular structures. Denosumab, a monoclonal antibody targeting RANKL, has emerged as an important adjuvant therapy for unresectable or surgically challenging GCTB. Long-term outcomes of combined surgical resection and denosumab therapy in cervical spine GCTB remain poorly documented. <h3>Case Report:</h3> We report the case of a 16-year-old Japanese male with a history of malignant lymphoma who presented with neck pain and a lytic lesion of the C2 vertebral body. Imaging revealed a 3.5×2.8×2.5 cm expansile lesion with extraosseous extension and encasement of the right vertebral artery. Biopsy confirmed GCTB. The patient received preoperative denosumab (120 mg on days 1, 8, and 15 of month 1, then monthly for 7 additional months) followed by right vertebral artery embolization. A two-stage anterior-posterior surgical resection was performed <i>via</i> mandibular osteotomy, with C1 lateral mass and C3 pedicle screw fixation and tricortical iliac crest autograft reconstruction. Postoperative denosumab (120 mg monthly) was continued for 16 months. At 10-year follow-up, the patient remains recurrence-free with solid bony fusion, no neurological deficits, and excellent functional outcomes (VAS 0/10, JOA score 17/17). <h3>Conclusion:</h3> This case demonstrates that combined anterior-posterior surgical resection with perioperative denosumab therapy can achieve excellent long-term tumor control and functional outcomes in C2 GCTB. Extended preoperative denosumab facilitated tumor ossification and surgical resection, while postoperative denosumab may reduce recurrence risk. Long-term surveillance remains essential given the variable recurrence patterns in spinal GCTB.