Late resolution of brown tumor two years after parathyroidectomy: Case report with eight years follow-up

Abstract

Brown tumors are a type of non-neoplastic lesion characterized by the presence of osteolytic bone lesions in patients with hyperparathyroidism. These lesions are more commonly seen in females, older patients, and can also occur in other bones such as the femur, clavicle, ribs, and pelvis. This case report aims to highlight a rare case of a male patient who was diagnosed with a brown tumor two years after undergoing parathyroidectomy for parathyroid carcinoma. PTH, calcium, and phosphate levels were within normal ranges. Histopathological analysis revealed features indistinguishable from a giant cell–rich lesion; however, normal PTH, calcium, and phosphate levels excluded active hyperparathyroidism, supporting the diagnosis of a residual brown tumor. The lesion was considered an old brown tumor caused by hyperparathyroidism secondary to parathyroid carcinoma. Clinical and radiological follow-ups were conducted over an 8-year period, demonstrating bone neoformation with no signs of recurrence. Prosthetic rehabilitation was completed. Comprehensive evaluation of brown tumors is essential to ensure accurate diagnosis and appropriate treatment. Parathyroid carcinoma can also be a cause of hyperparathyroidism and can be related to a poor outcome if not treated adequately. These bone lesions should be a sign for a judicious systemic evaluation to be performed to exclude malignancies and also discover if there is an underlying cause. Late detection of a jaw brown tumor after parathyroidectomy with normal biochemical parameters is exceedingly rare, particularly in male patients.