Giant cell tumor of the cervical spine treated by carbon ion radiotherapy: A case report.

Introduction Giant cell tumor (GCT) of the bone is a benign-malignant intermediate tumor with locally destructive growth and a relatively high local recurrence rate. Neurological symptoms may develop in patients with GCT of the spine, and surgical treatment is prioritized in cases where resection is possible. However, the local recurrence rate of GCT of the bone is higher than that of GCT at other sites owing to the associated surgical challenges, and treatment is often difficult. No study to date has reported long-term remission of recurrent tumors for more than 5 years by treatment with carbon ion beam radiotherapy after resection of GCT of the cervical spine. Patient concerns A 14-year-old boy who experienced recurrence after surgery for GCT of the cervical spine. Diagnosis The patient presented with cervical pain, and computed tomography revealed a mass of the C2 vertebral body. He underwent surgery for tumor resection and autologous bone grafting, and the final pathological diagnosis was GCT. The transplanted bone exhibited gradual progression of resorption, and recurrent tumors were observed on computed tomography and magnetic resonance imaging 1 year and 4 months after surgery. Interventions The patient was started on denosumab at 15 years of age and received carbon ion beam therapy with 70.4 Gy administered in 32 sessions over 7 weeks. Outcomes No progressive tumor growth was observed, there were no neurological symptoms such as paralysis or pain were noted, and the patient was in remission for 5 years after irradiation. Conclusion These findings suggest that carbon ion radiotherapy is a safe and effective therapeutic option for patients with recurrent GCT of the cervical spine.