Fractionated stereotactic radiotherapy (FSRT) for optic glioma

Purpose: To determine efficacy and toxicity of fractionated stereotactic ra diotherapy (FSRT) in patients with optic glioma, Methods and Materials: Ten patients suffering from optic glioma were treate d by FSRT between December 1990 and December 1995 at the German Cancer Rese arch Center (DKFZ) in Heidelberg, Eight patients were treated for progressi ve recurrent tumor following partial tumor resection and 2 patients were tr eated postoperatively. Dose distributions were calculated by a 3D treatment planning system (Voxelplan, Heidelberg), Patients were treated with a noni nvasive repeatable stereotactic fixation system using a manually driven mid size multileaf collimator attached to a linear accelerator. We applied a me dian prescribed total dose to the isocenter of 52.4 Gy with a median daily fraction size of 1.8 Gy. Results: All patients treated by definitive radiotherapy remained free from local tumor progression during the follow-up period (range 12-72 months) e xcept the 1 patient treated for recurrence after previous radiotherapy. A c omplete remission was achieved in 3 patients with subsequent improvement of visual acuity, None of the patients with locally controlled tumor experien ced any further impairment of vision. One patient developed new ACTH defici ency. No other clinically significant late effects attributable to radiothe rapy were observed. Conclusion: FSRT permits treatment of optic glioma with excellent tumor con trol and without clinically relevant morbidity, Compared to conventional te chniques there is the potential of sparing the pituitary gland in chiasmati c lesions, (C) 1999 Elsevier Science Inc.