SURGICAL TREATMENT OF GIANT PITUITARY ADENOMAS

Giant pituitary adenomas, defined as those measuring at least 4 cm in maximum diameter, are a therapeutic challenge. We report our experience in a large, consecutive series of patients with giant adenomas.Between 1990 and 2004, 95 patients with a giant pituitary adenomas underwent surgery at our department. Nonfunctioning pituitary adenoma was the most frequent type (n = 70; 73.7%), whereas hormone-secreting adenomas numbered only 25 (26.3%). The mean age at the time of surgery (+/-standard error of the mean) was 48.4 +/- 1.5 years; there were 66 men (69.5%) and 29 women (20.5%).In total, 111 surgical procedures were performed. Of these, 85 approaches (76.6%) were transsphenoidal and 26 (23.4%) were transcranial. Visual improvement occurred in 59 of the 79 patients with preoperative defect who could be evaluated after surgery (74.7%). Radical tumor excision was obtained in 14 patients (14.7%). Adjuvant medical and radiation therapies led to 74.5% (95% confidence interval, 62.7-86.4%) control of tumor growth at 5 years. This was not different in patients with nonfunctioning pituitary adenomas compared with patients with hormone-secreting tumors. In the subgroup of patients with nonfunctioning pituitary adenomas, radiation therapy had a protective role against tumor growth (P < 0.01).Maximal surgical removal of giant adenomas through the transsphenoidal or transcranial approach, or both, aimed to relieve compression of the optic pathway and reduce tumor volume as much as possible, offers the best chances to control the tumor when followed with adjuvant medical and radiation therapies.