ИСТИНА

Keywords: glioblastoma, radiosurgery, hypofractionation, CyberKnife, brain, malignant glioma Study objective: retrospective analysis of results of CyberKnife radiosurgery and hypofractionated irradiation for small to medium-size progression of supratentorial malignant glioma in 61 selected patients treated in Burdenko Neurosurgical Institute in 2009-2016. Patients and methods: 32 men and 29 women was included, mean age was 47,2 years. 39 patients had primary glioblastoma, 5 - secondary glioblastoma, 6 - anaplastic astrocytoma, 7 - anaplastic oligoastrocytoma and 4 had anaplastic oligodendroglioma. 60 patient underwent tumor removal and 1 stereotactic biopsy. 57 patients received postoperative radiotherapy with 58-60 Gy in 29-33 fractions and other 4 had shorter courses (33-45 Gy in 12-18 fractions). Patients with glioblastoma and anaplastic astrocytoma received temozolomide 75 mg/m2 during radiotherapy. After completion of radiotherapy 54 patients received adjuvant chemotherapy (35 had temozolomide-based regimen and 19 - other regimens). Mean time from completion of radiotherapy to first progression was 8,2 months in glioblastoma group (44 patients) and 16,3 months in anaplastic glioma group (17 patients). First progression as single growing lesion in primary tumor region (local type of "monofocal" progression) was observed 31 of 44 (70%) glioblastoma and 14 of 17 (82%) anaplastic glioma patients. 6 glioblastoma and non of anaplastic glioma patients had distant type of monofocal progression (single distant new lesion with absence of progression in primary tumor region ). Other 12 patients had "multifocal" progression (2 had several local growing foci, 2 had several distant foci and 8 had at least 1 growing local lesion and 1 new distant lesion). Lesions with volume less than 11 cm3 was treated with single median dose of 20 Gy, bigger lesions (up to 58 cm3, median volume - 12,7 cm3) were irradiated with 3 to 7 fractions up to total dose of 21-39,5 Gy (every day or every other day). Mean follow-up was 13,3 months after CyberKnife salvage irradiation. Results: mean time from salvage irradiation to second progression was 8,2 months in glioblastoma group and 17,2 months in anaplastic glioma group; overall survival after salvage irradiation was 16,5 and 31 month respectively. In 6 of 92 irradiated lesions (6,5%) clinically significant adverse radiation effect developed, all were treated successfully with bevacizumab. In primary glioblastoma group (39 patients) addition of more than 3 infusions of 400 mg bevacizumab to CyberKnife treatment was statistically significant associated with better overall survival (p=0.01). Conclusion: CyberKnife irradiation with bevacizumab is an effective option for monofocal and multifocal forms of supratentorial glioblastoma progression.