Giant Cell Tumor of the Cranial Vault: A Rare Frontotemporal Case With Complete Neurological Recovery and Narrative Review

Giant cell tumor of bone (GCTB) represents less than 1% of primary bone tumors, with cranial localization being exceptionally rare, accounting for 0.5-1% of all GCTB cases. Within cranial GCTB, the vast majority arise from endochondral skull-base bones (sphenoid, temporal, and clivus), while true calvarial involvement of membranous bones represents only 4% of cases. We present an 18-year-old male with a frontotemporal calvarial GCTB who underwent successful surgical resection with complete neurological recovery despite postoperative hemiparesis. The tumor demonstrated classic histopathological and immunohistochemical features, including CD68 positivity, approximately 10% Ki-67 proliferative index, and osteoclast-like multinucleated giant cells. Following gross total resection with wide margins to healthy dura and cranioplasty reconstruction, the patient experienced complete resolution of motor and speech deficits within six weeks through intensive rehabilitation. Postoperative magnetic resonance imaging confirmed complete tumor removal with no evidence of residual disease. This case is discussed within the context of a comprehensive narrative review highlighting the distinct biological behavior of calvarial GCTB compared to skull-base lesions, the critical importance of achieving gross total resection, and the emerging role of molecular diagnosis (H3F3A G34W mutation) and adjuvant therapies including denosumab. Calvarial GCTB offers superior surgical accessibility and prognosis compared to skull-base counterparts, with appropriately aggressive resection typically achieving cure without need for radiotherapy, thereby avoiding the well-documented risk of radiation-induced malignant transformation.