Multicentric Giant Cell Tumor of Bone and Paraganglioma: A Case Report.

Abstract

Giant cell tumor (GCT) of bone accounts for 4% to 5% of primary bone tumors1. Distant metastasis occurs most commonly in the lung, reported at a rate of 2% to 5%2,3, although the overall outcome of metastatic GCT is favorable2. Recently, it was reported that the receptor activator of nuclear factor kappa-B ligand (RANKL) might play a pivotal role in osteoclast differentiation in the genesis of GCT4. However, the precise mechanism of GCT development remains obscure. Multicentric giant cell tumor (MGCT) of bone is exceedingly rare, affecting approximately 1% of all patients with GCT5. There is no substantial difference between solitary GCT and MGCT regarding the clinicopathological features6,7. We report the case of a twenty-year-old man with both MGCT and paraganglioma, who developed multiple distant metastases from each lesion. The patient’s parents were informed that data concerning the case would be submitted for publication, and they provided consent. A twenty-year-old man was referred to us because of a six-month history of pain in the left knee. The pain was recurrent, but remission of the pain was present at times, although the pain gradually increased in severity. There was no history of trauma. The medical history was otherwise unremarkable. Physical examination revealed no inflammation, swelling, local heat, or tenderness. The patient’s temperature, pulse rate, and blood pressure were normal. Radiographs of the affected knee showed expansile lytic lesions with trabeculation and cortical thinning in the epiphysis and metaphysis of the distal part of the femur, the proximal part of the tibia, and the proximal part of the fibula. These lesions showed no periosteal reaction or mineralized matrix. A lytic bone lesion with trabeculation was also observed in the distal part of the ipsilateral tibia (Figs. …