Giant and Multicompartmental Pituitary Adenomas
Last Updated: March 13, 2020
Giant pituitary adenomas are usually described as tumors larger than 4 cm that generally extend within 6 mm of the foramen of Monro. They are reported in 5% to 14% of surgical pituitary tumor series. The histologic characteristics of giant pituitary adenomas do not correlate with their size or invasive nature; most of these tumors contain benign cells.
Most giant pituitary adenomas require surgical excision. An exception to this rule is the rare giant prolactinoma, which has a high rate of response and regression with dopamine agonist therapy.
Over the last century, surgery for giant pituitary adenomas has evolved from transcranial macrosurgical techniques associated with significant morbidity to transcranial microsurgical techniques, and ultimately to endonasal endoscopic transsphenoidal approaches with improved patient outcomes.
However, in inexperienced hands, the transnasal approaches can potentially result in subtotal resection of pituitary tumors and especially the giant ones. The residual tumor can induce a postoperative apoplectic event, leading to irreversible neurologic dete...