A Study of the Boron Neutron Capture Therapy (BNCT) Using B10 L-BPA in Malignant Brain Tumors

This study is testing boron neutron capture therapy (BNCT) — a specialized type of radiation treatment that uses a boron compound and neutron beams to selectively destroy cancer cells — for people with malignant brain tumors (grade 3 or 4) that have already been treated before. **You may be eligible if...** - You are 18 or older with a confirmed grade 3 or 4 malignant brain tumor (excluding certain specific subtypes) - You have a measurable tumor on MRI/CT and at least one lesion that can be tracked per standard criteria - It has been at least 3 months since your last radiation therapy and at least 1 month since chemotherapy - Your tumor volume is small enough (under 250 cm³, longest dimension under 7 cm) - Your general health and organ function meet the study requirements **You may NOT be eligible if...** - You have a primary CNS lymphoma, medulloblastoma, or grade 3 ependymoma - Your tumor is too large for safe treatment - Your overall health or organ function is too poor for the treatment - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.