STMO-15 OUR THERAPEUTIC STRATEGIES FOR GLIOBLASTOMA: INTRAOPERATIVE SUPPORT SYSTEMS [INTRAOPERATIVE MRI, PET, 5-AMINOLEVULINIC ACID (5-ALA)] AND NEOADJUVANT CHEMOTHERAPY

OBJECTIVE: Neuronavigation systems with MRI and multiple PET examinations (methionine [MET], fluorothymidine [FLT], and fluoromisonidazole [FMISO]) have become our standard techniques for glioma surgeries. Residual tumors are identified and removed using intraoperative MRI (IoMRI) to maximize tumor removal. This time, we performed tumor removal after Bevacizumab (Bev) therapy for glioblastoma with low KPS at admission and compared extraction rate and residual volume of MRI and PET examinations, and prognosis between with and without Bev therapy. METHODS: We selected 12 glioblastoma patients with low KPS at admission and performed multiple PET examinations and IoMRI from January 2016 to July 2019. We divided them into the pre-Bev group that performed tumor removal after neoadjuvant Bev therapy and the non-Bev group that did not use Bev. We compared the extraction rate and residual volume of MRI and PET examinations, and prognosis between the pre-Bev group and the non-Bev group. RESULTS: The pre-Bev group was 6 cases and the non-Bev group was 6 cases. The number of KPS for the pre-Bev group just before surgery was (90; 3 cases, 80; 2 cases, 70; 1 case) and (50; 2 cases, 40; 4 cases) for the non-Bev group. For comparison between the pre Bev group and the non-Bev group, the extraction rate (%) was T1-Gd (97.6, 91.5), MET (95.4, 99.9), FLT (96.2, 90.2), FMISO (97, 92), residual volume (ml) was T1-Gd (0.6, 1.7), MET (1.2, 2.9), FLT (1.0, 2.1), FMISO (0.5, 1.1), and for prognosis, median PFS (month) is (10.1, 4.9) and median OS (months) was (15.7, 13.3). CONCLUSIONS: For glioblastoma patients with low KPS at admission, the neoadjuvant Bev therapy improved KPS just before surgery. The neoadjuvant Bev therapy improved the extraction rate and reduced residual volume of MRI and PET examinations and leads to the prolonged prognosis of PFS and OS.