Parathyroid cyst: the forgotten diagnosis of a neck mass.

The differential diagnosis of cystic cervical masses includes cystic thyroid disease or some embryological diseases. Parathyroid cyst is one of the less common causes of the cervical masses. The Swedish anatomist Sandstrom reported the first description of parathyroid cyst in 1880. Up to date, only about 300 cases have been reported in the world literature. They may be functional or nonfunctional, depending on the presence or absence of the hyperparathyroidism and treatment options vary for both presentations. Particularly, nonfunctional cysts are often considered as thyroid cysts. Diagnosis is best made by monitoring serum calcium levels and sending cyst fluid for parathormone analysis. We herein report a patient diagnosed with a parathyroid cyst who had received the diagnosis of goitre at other institute; including a review of the literature.