CTNI-66. THE PREOPERATIVE BRAIN IRRADIATION IN GLIOBLASTOMA (POBIG) STUDY: A NOVEL TREATMENT PARADIGM TO IMPROVE OUTCOMES?

Abstract OBJECTIVE The Preoperative Brain Irradiation in Glioblastoma (POBIG) study evaluates for the first time safety, feasibility, and impact of single fraction preoperative radiotherapy newly diagnosed glioblastoma patients. METHODS Operable patients with a radiological diagnosis glioblastoma, by consensus multidisciplinary tumor board including two dedicated neuro-radiologists, are screened study. Anatomical functional MRI sequences acquired further characterization planning. Radiotherapy is delivered approximately weeks after initial screening. Radiation targets macroscopic microscopic region at risk being left behind during surgery spares least 2cc volume debulked to safeguard unperturbed clinically relevant tissue examination molecular profiling. dose-escalates (from 8Gy 14Gy) based on time-to-event Continual Reassessment Methodology. Subsequently, undergo surgical debulking followed postoperative fractionated 60Gy/30fr concurrent temozolomide. RESULTS POBIG patient underwent subtotal resection posterior fronto-opercular completed chemoradiotherapy. Screening, consent, imaging analysis, planning delivery until can be achieved within three from screening while maintaining adequate personalized communication. There were no or delays complications. During surgery, we successfully sampled unirradiated irradiated regions. field covered whole remnant tumor, image-guided obtained samples analysis showed clear evidence differential radiation-induced changes. CONCLUSION We initiated new treatment strategy treatment, now open recruitment. Paired sampling advanced promising results. offers unique opportunity paradigm shift towards regimens, hopefully leading better outcomes.