A Ketogenic Diet as a Complementary Treatment on Patients With High-grade Gliomas and Brain Metastases

This trial is testing whether a ketogenic diet (a high-fat, very low-carbohydrate eating plan) can complement standard treatment for people with high-grade brain tumors — specifically glioblastoma (grade 4) or brain metastases. The idea is that cancer cells are heavily reliant on sugar for energy, and severely cutting carbohydrates may slow their growth. **You may be eligible if...** - You are between 18 and 80 years old - You have been newly diagnosed with glioblastoma grade 4, OR your brain tumor has recurred after surgery, radiation, and chemotherapy - You have normal liver and kidney function - Your performance status (Karnofsky Score) is 50 or above (able to care for most of your own needs) - You can give informed consent **You may NOT be eligible if...** - You have diabetes mellitus - Your life expectancy is more than 3 months (note: this is an unusual exclusion — confirm with your doctor) - You are unable to follow a strict dietary regimen - You had your gallbladder removed within the past year - You have a genetic disorder of fat metabolism Talk to your doctor to see if this trial is right for you.