Abstract
Giant cell tumor of the bone (GCTB) is a benign bone tumor that can occasionally progress to malignancy, usually in chronic cases. It is a common benign and aggressive bone tumor that affects patients aged between 20 and 45 years. The most common location is the knee joint. It manifests as a painless or occasionally painful swelling over the affected area. A case of giant cell tumor (GCT) of the proximal tibia in a 72-year-old male is reported here, which was difficult to diagnose as it is rarely found in the geriatric age group. The patient came with a chief complaint of pain and swelling over his left knee for two months with a history of trauma to the knee a couple of times. On clinical examination, the patient had grade 3 tenderness and swelling on the anterolateral aspect of the knee extending toward the proximal tibia. The swelling was well-defined, smooth, firm, and uniform in consistency with dimensions of 15 cm × 12 cm. The swelling was moveable sideways, and the movement of the knee suggested that it was not attached to the underlying bone. As per the age and history of the rapid-growing lesion, we suspected malignancy, but clinical findings were pointing toward benign tumor. X-ray of the affected knee was done, which revealed a soft tissue mass with the involvement of the bone. Magnetic resonance imaging (MRI) of the knee revealed a soft tissue mass with the cortical breach. An open biopsy was done for the confirmation of the diagnosis, which was later reported and confirmed as a giant cell tumor of the proximal tibia. As bone tumor is associated with a cortical breach and pathological fracture, it was classified under Campanacci grade 3, for which an en bloc resection and open reduction and internal fixation with plate osteosynthesis with bone cementing and bone grafting were done followed by knee bending physiotherapy and gradual weight-bearing. Finally, the knee function was improved with pain relief.