[Brown bone tumor as the first manifestation of primary hyperparathyroidism]

We report a clinical case of a 26 years old female who had a 2 years evolution chin tumour with hypercalcemia (11.8 mg/dl) and PTH (paratohormone) of 761 pg/ml. She underwent a CT scan and MRI of the mandible, as well as a biopsy followed by excision of the tumour by the maxilofacial surgeons. Our ENT Department asked for a Scintigraphy (Tc99s-mibi) and thoracic-cervical CT, which showed a lesion that turned out to be an adenoma of the lower right parathyroid gland after surgery and pathological examination. The patient suffered a Primary hyperparathyroidism that was the main stimulus for the Brown Tumour made up by macrophagos and multinuclear giant cells, being this the first manifestation of the metabolic disorder. This form of hyperparathyroidism is very rare in the clinic. We do a literature review to establish the differential diagnosis for such pathology.