Thymic carcinoid and parathyroid hyperplasia detection with Tc-99m-MIBI men type 1

We report a case of a 35-year-old male, with a history of diarrhea, renal l ithiasis with frequent expulsions of calculus and hypercalcemia during the last 2 years. The patient was studied and diagnosed with a multiple endocri ne neoplasia type I (MEN I), familiar (mother with MEN I). A scintigraphic study with Tc-99m-MIBI was performed in order to localize hyperfunctioning parathyroid glands because of biochemical diagnosis of primary hyperparathy roidism. Double phase Tc-99m-MIBI scan detected one hyperfunctioning parath yroid gland and a large anterior mediastinal mass. Subsequent, plain radiog raph and CT of the chest showed a soft-tissue mass in that localization. Pu nch biopsy of the lesion guided by CT revealed malignant cells of neuroendo crine tumor. The tumor was removed and histologically confirmed as a carcin oid within a thymus in a MEN type I syndrome. MEN I patients can benefit fr om the examination with this agent which can potentially localize not only parathyroid endocrine pathology but also unknown associated tumors. (J. End ocrinol. Invest. 22: 803-807, 1999) (C)1999, Editrice Kurtis.