Nonfunctioning pituitary tumors and pituitary incidentalomas.

Clinically nonfunctioning adenomas (CNFAs) range from being completely asymptomatic, and therefore detected at autopsy or as incidental findings on head MRI or CT scans performed for other reasons, to causing significant hypothalamic/pituitary dysfunction and visual field compromise because of their large size. Patients with incidental adenomas should be screened for hypersecretion and hyposecretion. In the absence of hypersecretion, hypopituitarism, or visual field defects, patients may be followed by periodic screening by MRI for enlargement. Symptomatic patients with CNFAs are generally treated by transsphenoidal resection. Postoperative MRI scans are done at 3 to 4 months after surgery to assess for completeness of resection and then repeated yearly for 3 to 5 years and subsequently less frequently to assess for regrowth. The regrowth rate may be substantially reduced with the use of dopamine agonists and radiotherapy.