1 in 5
Almost 20% may have pituitary tumors but most will remain undetected as they do not cause any symptoms.
Those that grow large enough to cause symptoms due to size or secrete enough of one of many hormones that the pituitary normally secretes may need to be treated with medicines or surgery. Prognosis is generally good. Visit: http://www.Ncbi.Nlm.Nih.Gov/pubmedhealth/pmh0001723/.