Radiation therapy for pituitary adenomas. A retrospective study of the University of Louisville experience.

A retrospective analysis of treatment outcome was performed on patients treated with radiation for pituitary adenomas at the University of Louisville from January 1988 to December 1992. The study population included 27 patients. Twenty received radiation as a component of their initial treatment while seven received radiation as part of their treatment for recurrent disease. Nineteen patients were treated with post-operative radiation, and eight were treated with radiation alone. Follow-up interval ranged from 1 month to 109 months, with a median of 28 months. All three patients with stage I disease were controlled with radiation alone (1/3) or combined surgery and postoperative radiation (2/3), whereas six of eight stage II patients had disease control following surgery and postoperative radiation. Both patients with stage III adenomas treated with radiation alone had local control, whereas local control was achieved in six of seven with post-operative radiation. Three of five patients with recurrent disease had local control with radiation alone, whereas both patients undergoing surgery and postoperative radiation had local control. This retrospective analysis supports previous findings that radiation therapy alone or combined with transphenoidal resection is effective in long-term control of pituitary adenomas. It further suggests that immediate radiation therapy may be superior to radiation for surgical or medical failures.