Mediastinal parathyroid adenomas. A cause of persistent hyperparathyroidism.

Unrecognized mediastinal parathyroid adenomas that are inaccessible via a standard cervical exploration are an important cause of persistent primary hyperparathyroidism. Of 26 patients evaluated at UCLA Medical Center for persistent primary hyperparathyroidism, six required sternotomy (5) or thoracotomy (1) for cure of their disease. Analysis of these six patients suggests that aberrant embryologic development is the most logical explanation for the ectopic location of these mediastinal adenomas. In most instances, preoperative localization of the adenoma is possible. Permanent hypoparathyroidism occurs in a significant percentage of patients undergoing reoperative parathyroid surgery. Efforts to minimize postoperative morbidity should include a careful and systematic approach to the preoperative and intraoperative management of patients with mediastinal adenomas, as well as consideration of autotransplantation or cryopreservation of parathyroid tissue.