Intrathyroidal Parathyroid Adenoma.

Intrathyroidal parathyroid adenoma is a rare anomaly with an incidence of 1.4-6%. A cause of failure in the therapeutic management of hyperparathyroidism is the ectopic localization of the adenoma, particularly intrathyroidal. This is the case of a 51-year-old patient with no particular pathological history who presented with neck pain and whose clinical examination revealed a goiter. Parathyroid myocardial perfusion imaging (MIBI) scintigraphy revealed an elective MIBI-fixing focus with an upper left polar projection compatible with a parathyroid origin. A left loboishmectomy was performed. Anatomopathological study showed a parathyroid adenoma associated with dystrophic thyroid parenchyma, with no obvious histological signs of malignancy. Post-therapeutic laboratory work-up was normalized. Parathyroid adenoma, intrathyroidal, is an uncommon lesion but may be responsible for therapeutic failure in hyperparathyroidism. MIBI parathyroid gland scintigraphy is the gold standard for the diagnosis of parathyroid ectopy.