Parathyroid cysts. Report of four cases and review of the literature.

Though a rare lesion, a parathyroid cyst is of clinical significance because it mimics a thyroid cyst and can be associated with hyperparathyroidism. The cyst can be ectopic in location and therefore constitutes a differential diagnosis to a bronchial or thymic cyst. Four cases of parathyroid cyst are presented. Fine needle aspiration with parathyroid hormone assay is diagnostic. Surgical removal of the cyst is recommended.