Frameless Fractionated Stereotactic Radiotherapy using Linear Accelerator in Pituitary Adenomas

ABSTRACT

OBJECTIVE: The goal of this study is to evaluate the efficacy and outcome of frameless fractionated stereotactic radiotherapy (FSRT) for pituitary adenomas. METHODS: The authors reviewed medical records of 15 patients who were treated by FSRT between January 1997 and December 2002. We used `oint Reference System' of Northwest Medical Physics Center. Three patients received radiotherapy as primary treatment and 12 patients received it postoperatively for residual mass. The mean dose of FSRT was 34.8Gy. Responses of the tumor size, serum hormone level, change of the visual field, and complication were evaluated. The follow-up duration ranged from 6 to 61 months (mean 20.3 months). RESULTS: They consisted of 4 prolactinomas, 3 growth hormone secreting tumors, 2 Cushing's diseases, and 6 nonfunctioning tumors. Overall tumor control rate and the mean tumor volume reduction rate were 86.7% (13/15 patients), 53.6% respectively. Reduction or normalization of hormone level were achieved in 5 of 9 patients, and mean duration was 17.5 months. Visual field defect improved in 3 of 10 patients. Acute complications were temporary headache, dizziness, local alopecia, nausea and vomiting. None of patients showed radionecrosis, panhypopituitarism, and visual impairment. CONCLUSION: Frameless fractionated stereotactic radiotherapy seems to be an effective and safe treatment in pituitary adenoma.