A Case of Recurrent Ectopic Parathyroid Adenoma Developed 22 Years after the Initial Parathyroidectomy

Persistent or recurrent primary hyperparathyroidism after initi al parathyroid surgery occurs at rates of 1.5~10%. A single missed parathyroid adenoma accounts for the majority of persistent hyperparathyroidism, whereas metachronous parathyroid adenoma is a rare cause of recurrent hypercalcemia. We report a case of a 39-year-old female who presented with recurrent pancreatitis. She had symptoms of hyperparathyroidism such as hypercalcemia, hypophosphatemia, hypercalciuria, nephrocalcinosis, and osteoporosis. She had a 2-cm firm neck mass under the right sub mandibular area. She was diagnosed with primary hyperparathyroidism 22 years ago. At that time, the right upper and lower parathyroid glands were removed after exploration of all parathyroid glands, and a right upper parathyroid adenoma was diagnosed. Now, she had a second surgery to remove the right submandibular mass with intraoperative PTH monitoring, which was diagnosed as a parathyroid adenoma in an ectopic supernumerary parathyroid gland. Because of hungry bone syndrome, she received calcium carbonate replacement therapy and has no evidence of recurrence. Here, we report a recurrent parathyroid adenoma in the undescended, supernumerary parathyroid gland after a long interval from the initial surgery. (J Korean Endocr Soc 24:260~264, 2009)