OBJECTIVE: Radiation therapy is recommended for @entity977 that are refractory to surgical and medical therapies. The efficacy of single-fraction radiosurgery is established for these lesions, but lesions within 3 mm of the optic pathway cannot be safely treated with doses higher than 8 to 10 Gy. We hypothesized that the optic nerve will tolerate 5 consecutive daily radiosurgery fractions of 500 cGy with effective @entity5 control. METHODS: We reviewed our first 20 @entity1 with recurrent or residual @entity977 within 3 mm of the optic chiasm treated with the CyberKnife radiosurgery system (Accuray, Inc., Sunnyvale, CA). @entity5 were treated with a mean coverage of 97 +/- 2.2% (range, 89.8-99.7%), a mean conformity index of 1.3 +/- 0.2 (range, 1.1-1.6), and a mean treatment isodose line of 74.5 +/- 6.6% (range, 60-86%). The primary end point was an interim analysis of visual preservation, and secondary end points were @entity5 control. RESULTS: The mean follow-up period for visual field testing was 26.6 +/- 10.5 months (range, 10.6-41 months). The vision of all 14 @entity1 with intact preoperative vision remained intact. Of the 5 @entity1 with @entity227 , 2 remained stable, and 3 improved. No @entity1 's vision deteriorated. The mean radiographic follow-up was 29.3 +/- 8.6 months (range, 10.2-40.5 months). On magnetic resonance imaging, 12 @entity5 were stable, 8 were smaller, and none enlarged. CONCLUSION: This preliminary study establishes that the optic nerve and chiasm tolerate CyberKnife hypofractionated radiosurgery of 5 x 500 cGy to perichiasmatic @entity977 . Early data suggest that this dosing paradigm may achieve satisfactory @entity5 control for these challenging lesions, but longer follow-up is necessary to confirm these results.

Hypofractionated CyberKnife radiosurgery for perichiasmatic XXXX : early results.

@entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'Tumors', 'tumors', 'radiographic and endocrinological tumor'] @entity1 :: ('9606', 'Species') :: ['patients', 'patient'] @entity227 :: ('MESH:D014786', 'Disease') :: ['impaired vision'] @entity977 :: ('MESH:D010911', 'Disease') :: ['pituitary adenomas', 'pituitary tumors']
@entity977 :: (MESH:D010911,Disease) :: ['pituitary adenomas']
