Giant Cell Tumor of the Spine

Giant cell tumor (GCT) of the spine is a rare condition characterized by locally aggressive osteolytic tumors. While GCTs commonly occur in the epiphysiometaphysis of long bones, spinal lesions are relatively uncommon. The pathologic features of GCTs involve a vascularized stroma composed of spindle-shaped mononuclear cells and multinucleated giant cells. Although GCTs are typically considered benign, approximately 10% may exhibit malignant behavior. Spinal GCTs can present with pain, weakness, and neurological deficits due to compression of neural elements. Imaging techniques such as conventional radiography, computed tomography (CT), magnetic resonance imaging (MRI), and PET/CT can help in diagnosis and staging. The solid portions of GCTs typically demonstrate low signal intensity on T2-weighted images (WI) and intermediate signal intensity on T1-WI, due to the presence of collagen within the fibrous components and hemosiderin deposition. Treatment typically involves complete resection of the tumor, preferably with en bloc resection for better prognosis. However, surgery may be challenging due to the soft and easily ruptured nature of GCTs. In cases where complete surgical resection is not feasible or the tumor exhibits aggressive behavior, adjuvant treatments such as radiotherapy may be considered to control local disease progression, while the use of denosumab has shown promise in reducing tumor size and inhibiting osteolysis in unresectable or recurrent giant cell tumors of the spine. Histopathological verification is essential for a definitive diagnosis, and differential diagnoses include other bone tumors and cystic lesions. Various classification systems exist to assess the aggressiveness and guide treatment decisions, although their correlation with local recurrence and metastases is uncertain.