Undescended superior parathyroid: A case report

Aberrant migration of parathyroid glands from their embryologic origin may result in undescended parathyroid glands. We present a case of an ectopic parathyroid adenoma at the level of the pyriform sinus. A 41‐year‐old female was evaluated for primary hyperparathyroidism. Following non‐localizing ultrasound and planar sestamibi imaging, the patient underwent SPECT/CT and 4‐D computed tomography demonstrating evidence of an ectopic parathyroid adenoma. The surgical approach was modified based on the location. Following extirpation, PTH fell from 80 to 16 pg/mL, and the 15‐min post‐excision level remained stable at 14pg/mL, indicating a biochemical cure. While rare, undescended parathyroid adenoma should be considered when preoperative imaging fails to identify a target adenoma or after unsuccessful surgery. The combined use of 99m Tc‐MBI or 4D CT and other anatomical scans may improve diagnostic accuracy. Due to the potential need to perform a second incision to conduct a four‐gland exploration, preoperative patient discussion regarding surgical risks may differ from that of a standard parathyroidectomy.