A Rare Case of Giant Cell Tumor of the First Metatarsal: En Bloc Resection and Fibular Autograft Reconstruction.

Introduction: Giant cell tumors (GCTs) of bone are benign but locally aggressive neoplasms that predominantly involve the epiphyseal regions of long bones, with the first metatarsal being an exceptionally rare site of involvement. This case report describes the clinical presentation, diagnostic evaluation, surgical management, and functional outcomes of a rare GCT involving the first metatarsal bone. Case Report: A 54-year-old female presented with a 5-month history of progressive pain and swelling of the right foot localized over the first metatarsal region. Clinical examination revealed a firm, tender, bony expansion measuring approximately 3 × 5 × 3 cm. Radiological investigations, including plain radiography, multiplanar MRI and CT imaging confirmed an osteolytic, expansile lesion suggestive of GCT. En bloc resection of the tumor-bearing segment was performed with reconstruction using non-vascularized fibular autograft fixation with K-wires. Histopathological examination confirmed the diagnosis of GCT of bone. Results: The patient achieved complete surgical resection with excellent functional recovery at 12-month follow-up. The fibular autograft demonstrated satisfactory integration without evidence of recurrence or significant complications. Functional outcome scores improved significantly, and the patient resumed normal weight-bearing activities. Conclusion: Although rare, GCT of the first metatarsal should be considered in the differential diagnosis of expansile osteolytic lesions in the foot. En bloc resection with non-vascularized fibular autograft reconstruction provides oncologically sound treatment with acceptable functional outcomes and minimal recurrence rates. This case underscores the importance of multimodal imaging, histopathological confirmation, and meticulous surgical planning in managing this challenging presentation.