Endocrine Abstracts

A palpable neck lump secondary to cystic parathyroid lesions is an exceptionally uncommon occurrence, accounting for only 0.01% of all neck masses. Cystic parathyroid adenomas can be asymptomatic, can cause compression to the nearby structures, or can rarely lead to hypercalcemia due to primary hyperparathyroidism (PHPT), which accounts for less than 2% of PHPT cases in the literature. Our case was a 75-year-old woman who presented with an acutely enlarging anterior neck swelling causing dysphagia, odynophagia, and hoarseness. Due to the acute onset of compressive symptoms, she was taken for surgical drainage on the suspicion of the swelling being an abscess or infected cyst. A biopsy was taken, and it was later confirmed that the swelling was a parathyroid cystadenoma. Her admission serum biochemistry showed hypercalcemia, hypophosphatemia, and hyperparathyroidism which were consistent with the biopsy results. Fatigue and polydipsia secondary to hypercalcemia showed up later, at which point she underwent surgery for the removal of the parathyroid cystadenoma with hemithyroidectomy. Intraoperative parathyroid monitoring showed a drop in parathyroid hormone levels, confirming a successful surgery. This case alerts clinicians about the rare presentation of parathyroid cystadenoma as an acutely enlarging neck swelling and it being a causative source of PHPT and hypercalcemia to prevent its accidental rupture during surgery leading to a potentially life-threatening hypercalcemic crisis.