Primary hyperparathyroidism presenting as a brown tumor in the mandible: a case report

BACKGROUND: Primary hyperparathyroidism is characterized by hypercalcemia and elevated or inappropriately normal serum levels of parathyroid hormone. Brown tumor of bone is a rare non-neoplastic lesion resulted from abnormal bone metabolism in hyperparathyroidism. However, nowadays, skeletal disease caused by primary hyperparathyroidism is uncommon. We report a case of brown tumor in the mandible as the initial exhibition of primary hyperparathyroidism associated with an atypical parathyroid adenoma. CASE PRESENTATION: The patient was a 49-year-old female, she had a pain mass on the right mandible a year ago and was treated with root canal therapy and marginal resection. After seven months, the mass recurred and enlarged. Enhanced CT scan, laboratory examination, Ultrasonography, (99m)Tc-MIBI SPECT-CT scintiscan and pathological examination were used to confirm the diagnosis of brown tumor. The patient’s symptom improved after parathyroidectomy. CONCLUSIONS: (99m)Tc-MIBI SPECT/CT scintigraphy is a highly sensitive examination of the localization diagnosis of hyperparathyroidism. Brown tumors should be considered in the differential diagnosis of osteolytic lesions to avoid unnecessary and harmful interventions.