Parathyroid cysts: a case report and review of the literature.

OBJECTIVES/HYPOTHESIS: Parathyroid cysts are rare clinical entities. They frequently present as a clinical diagnostic problem. They may mimic solitary thyroid nodules. The purpose of the study was to review the literature and present a case of a 22-year-old euthyroid woman presenting with recurrent swelling in the neck. Her complaints included choking and dysphagia. Fine-needle aspiration of the mass revealed clear, watery fluid with an extremely high level of calcium and c-terminal midmolecule parathyroid hormone assay in excess of 8000 pg/mL. Treatment consisted of neck exploration and removal of a 6 x 5-cm cystic encapsulated mass. Pathological diagnosis revealed a benign parathyroid cyst. The role of needle aspiration in diagnosing thyroid masses and the importance of parathyroid hormone assay in diagnosing parathyroid cyst are emphasized.