Unnoticed Giant Cell Tumor of the Left Distal Tibia in a 52-Year-Old Male: A Rare Case Report.

INTRODUCTION: Giant cell tumor (GCT) is a locally aggressive, benign primary bone tumor commonly affecting the epiphysis of long bones in young adults between 20 and 40 years. Occurrence in patients above 50 years is uncommon, and involvement of the distal tibia is relatively rare. Delayed or unnoticed presentation may lead to cortical breach and joint compromise. CASE REPORT: We report a 52-year-old male who presented with progressive pain and swelling over the left ankle for 5 months, initially treated as an ankle sprain elsewhere. Radiographs revealed an eccentric, expansile lytic lesion involving the distal tibial epiphysis extending to the metaphysis with cortical thinning. Magnetic resonance imaging showed subarticular extension without significant soft-tissue mass. Biopsy confirmed GCT. The patient underwent extended curettage, high-speed burring, chemical cauterization, and cavity filling with bone cement and stabilisation with a locking compression plate. At 12-month follow-up, there was no evidence of recurrence, and the patient had a good functional outcome. CONCLUSION: Distal tibial GCT in older patients can be easily missed due to atypical age presentation and atypical symptoms. Early imaging and biopsy are very important for diagnosis. Extended curettage with cement-augmented prophylactic plating provides satisfactory functional and oncological outcomes.