Nigora Rasulova, Qaisar Hussain Siraj, Amir Javaid, Anwar Al Banna.
Functional ectopic cystic parathyroid adenomas: case reports and literature review.
Pak J Nuclear Med Jan ;6(1):63-8.

Parathyroid adenomas are the commonest cause of primary hyperparathyroidism. About 10 percent of the parathyroid adenomas are ectopic in location. Cystic degeneration in parathyroid adenomas is seen in 4% of the cases and represents 1-2% of the cases with primary hyperparathyroidism. Hence, the combination of parathyroid cysts, which are both ectopic and functional is extremely rare. Functional parathyroid cysts can be either "silent" or associated with a wide range of clinical symptoms. We present two cases of functional mediastinal parathyroid cysts, one with and the other without clinical manifestations.

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