S356
Clinical - CNS
ESTRO 2026
Technology, Kurashiki Central Hospital, Okayama, Japan
highlighting the urgent need for alternative or combinatorial strategies to durably disrupt post- radiogenic tumor revascularization. The multicentric phase 1/2 GLORIA trial (NCT04121455) investigates CXCL12-targeted anti-vascular therapy as a novel approach for newly-diagnosed GBM. Material/Methods: The initial trial cohort combined RT and escalating doses of the CXCL12-neutralizing L-RNA-aptamer olaptesed pegol (NOX-A12) in patients with incompletely resected, newly-diagnosed IDH-wildtype GBM (CNS WHO grade 4) lacking MGMT promoter methylation. Concurrently with trial conduct, we performed spatial expression analyses, providing a rationale for dual inhibition of VEGF and CXCL12, two non-redundant, spatially distinct acting factors in tumor revascularization. Subsequently, we expanded the ongoing trial and six additional patients were included that additionally received the VEGF-targeting antibody bevacizumab (BEV) to RT and NOX-A12.The primary endpoint was safety. Secondary endpoints included radiographic response according to modified RANO criteria (mRANO) as well as perfusion imaging and clinical outcome. Results: In total, 16 patients were enrolled into the dose escalation arm and the BEV expansion arm. Treatment was well-tolerated and safe with no treatment-related deaths, resulting in abrogated tumor perfusion (rCBV, FTBhigh) and delayed tumor regrowth as per mRANO. Patients with RT+BEV+NOX-A12 showed deeper and longer lasting responses. Of these, one patient achieved complete remission, four partial response and one stable disease. Median PFS and OS after RT+BEV+NOX-A12 were 9.1 and 19.9 months, respectively, significantly outperforming RT+NOX-A12 (p=0.009; p=0.021) with two patients exceeding 2-year OS. Conclusion: Our findings establish proof-of-principle that dual inhibition of angio- and vasculogenesis following RTvia blockade of VEGF and CXCL12 is a safe and promising targeted strategy for patients with newly-diagnosed GBM. Keywords: glioblastoma, clinical trial, translational Digital Poster 608 Clinical outcomes of moderately hypofractionated stereotactic radiotherapy for meningiomas DAICHI TORIZUKA 1 , Keisuke Sakai 1 , Kota Fujii 1 , Hideki Hanazawa 1 , Mami Sakai 2 , Satoshi Itasaka 1 1 Department of Radiation Oncology, Kurashiki Central Hospital, Okayama, Japan. 2 Department of Medical
Purpose/Objective: Meningiomas are common benign tumors that can be managed through various approaches, including observation, surgical resection, and radiotherapy, with different dose-fractionation schedules.This study aimed to evaluate clinical outcomes and treatment- related adverse events in patients with meningioma treated with moderately hypofractionated stereotactic
radiotherapy (SRT). Material/Methods:
We retrospectively analyzed patients treated with moderately hypofractionated SRT for meningioma at our institution between April 2017 and December 2024. All patients underwent intensity-modulated radiation therapy at a prescribed dose of 39 Gy in 13 fractions to the planning target volume (PTV).The PTV was covered by the 80% isodose, corresponding to 48.75 Gy prescribed to the isocenter. Treatment efficacy was assessed using progression-free survival (PFS), and toxicity was evaluated according to the Common Terminology Criteria for Adverse Events version 5.0. PFS was calculated using the Kaplan–Meier method. Results: The study included 21 patients (22 lesions) with a median age of 66 years (range: 36–84 years). The cohort comprised seven males and 14 females, with histological grades I, II, and undetermined in 15, 4, and 2 patients, respectively.Tumor sites included the cerebral convexity (six lesions), falx cerebri (three), parasagittal venous sinus (three), sphenoid ridge (three) and others (seven).SRT was performed as initial treatment, postoperative radiotherapy, and postoperative recurrence in 2, 5, and 14 patients, respectively. The median PTV was 16.5 cm ³ (range: 1.3–133.6 cm ³ ). At a median follow-up of 26.5 months, the 3-year PFS rate was 90.9%. Two patients (PTV: 133.6 cm ³ and 19.4 cm ³ ) developed in-field recurrences and subsequently underwent surgical resection. No grade ≥ 3 acute or late radiotherapy- related adverse events were observed. Conclusion: Moderately hypofractionated SRT for meningioma is a safe and effective treatment with minimal adverse events. Further studies and long-term follow-ups are necessary to validate these findings. Keywords: meningioma, stereotactic radiotherapy
Digital Poster 749 Evaluating Optimal Dose and Field of Radiation Therapy in Pineal Parenchymal Tumors of
Made with FlippingBook - Share PDF online