DOI: https://doi.org/10.36347/sjds.2025.v12i01.001

Pages: 1-7

Brown tumors are osteolytic lesions that rarely indicate hyperparathyroidism. They usually occur in the terminal stage of primary or secondary hyperparathyroidism. Over the past three decades, the diagnosis of hyperparathyroidism has often been made during the asymptomatic phase, thanks to systematic calcium and parathyroid hormone levels. We report the case of a patient with primary hyperparathyroidism revealed by a maxillary tumor, whose CT scan revealed an aggressive osteolytic process. The anatomopathological examination revealed a benign giant cell tumor of the maxilla. The diagnosis of a brown tumor was suggested and confirmed after a phosphocalcic workup indicated hypercalcemia and hypophosphatemia. The etiological investigation revealed a right retro-thyroid nodule on cervical ultrasound, which after biopsy excision of the right inferior parathyroid gland confirmed the presence of a right inferior parathyroid adenoma, associated with homolateral lobectomy. A parathyroid hormone level of 1178 pmol/L (18 times the normal level) confirmed the diagnosis. This case study highlights the challenges in accurately diagnosing patients with osteolytic processes in the maxilla and underscores the necessity of investigating hyperparathyroidism in the presence of a giant cell lesion, given the insidious nature of this condition.