Stereotactic Radiosurgery with the CyberKnife for Pituitary Adenomas

Objective : In recent years, CyberKnife has emerged as an important treatment modality in the management of pituitary adenomas. Treatment results after performing CyberKnife and the complications of this procedure are reviewed, Methods : Twenty-six patients with pituitary adenomas received stereotactic radiosurgery with the CyberKnife (CKRS). The follow-up periods ranged from 7 months to 47 months (mean +/- SD : 30 +/- 12.7 months). The patients consisted of 17 with non-functioning adenomas, 3 with prolactinomas and 6 with acromegaly. The change in the tumor volume, visual acuity, hormonal function, and complications by this therapy were analyzed in each case. Results : The tumor control rate was 92.3%. Hormonal function was improved in all of the 9 (100%) functioning adenomas. Hormonal normalization was observed in 4 of the 9 (44%) patients with a mean duration of 16 months. In two patients (7.6%), visual acuity worsened due to cystic enlargement of the tumor after CKRS. No other complications were observed. Conclusion : CyberKnife is considered safe and effective in selected patients with pituitary adenomas. However, longer follow-up is required for a more complete assessment of late toxicity and treatment efficacy.