Abstract
High-grade gliomas (HGGs) are the most aggressive of brain tumors and are one of the most common primary intracranial malignancies. The poor prognosis after aggressive treatment of HGGs makes these gliomas a challenge to treat with curative intent. Proton radiation therapy is a recent radiation modality that is being explored for the treatment of HGGs. Proton radiation therapy provides improved sparing of critical normal structures while giving an ablative dose of radiation to the tumor, which can be performed more accurately than photon beam radiation therapy. We report a case of a diffuse HGG treated with proton radiotherapy and chemotherapy after previously being treated with photon irradiation. A complete radiographic response was seen on MRI imaging after proton irradiation.