Giant Cell Tumor of the Atlas: Case Report and Literature Review

Introduction: Giant cell tumor (GCT) is one of the most common primary bone tumors. It rarely occurs in the spine above the sacrum. Cervical spine vertebrae presentation of GCT is rare. These tumors account for less than 2% of all vertebral tumors and less than 1% of all giant cell tumors.

Objective: Describe a very rare case of GCT in the lateral mass of C1 and discuss surgical approach and literature review. Method: Case report and literature review performed in PubMed.

Results: Female, 30Y/O, started on Aug/2017 with neck pain, evocated by lateral and upward movements of the neck. At physical examination had neck pain worsened by palpation at occipito cervical junction levels. Cervical spine CT and MRI were requested, showing an osteolytic and expansive lesion at the topography of the anterior arch and lateral mass at the right side of C1. On Dec/2017 surgery was performed with macroscopic total resection of the C1 tumor followed by an occipito cervical fixation. A peacemeal resection of the tumor and bone drilling of the vertebral foramen, anterior arch of C1 and inferior portion of right occipital condile were needed for a macroscopic total tumor removal with right vertebral artery preservation. Patient was discharged without any neurological deficits and anatomopathological revealed a GCT (CD8+ / p63− / Ki67+ 10–20% / S100+). Surgery is the treatment of choice for a resectable GCT. It is a radiosensitive tumor and radiotherapy (RT) is a reasonable option if surgery is contraindicated, or in a situation where negative surgical margins can only be achieved with unacceptable morbidity. A major concern with RT is the risk of radiation induced malignant transformation, reason for what guidelines suggest that RT be considered only after other options have been exhausted. Newer therapeutic agents hold promise for patients for whom local therapies are not suitable. The characterization of the role of the RANK/RANKL axis in mediating the recruitment and function of osteoclast-like cells has provided a strong rationale for the use of targeted therapies, such as denosumab, which affect this pathway.

Conclusion: There are few cases of GCT described in the literature, especially considering lateral mass involvement as in the case above. The tactics and surgical strategies used for surgical resection vary according to each case in order to provide the maximum possible resection without promoting additional neurological deficits to the patient.