Optimizing Neurocognition With Whole Brain Radiation Therapy (WBRT) Using Upfront Pulsed Reduced Dose-Rate (PRDR) Technique

This study is testing a specialized type of whole-brain radiation therapy (called Pulsed Reduced Dose-Rate, or PRDR) to see if it is gentler on memory and thinking compared to standard whole-brain radiation. It is designed for people whose cancer has spread to the brain. **You may be eligible if...** - You are 18 or older and have cancer that has spread to the brain (brain metastases) - Your cancer was confirmed by biopsy or lab testing - You are in reasonably good physical health (able to carry out light activity) - Your life expectancy from your cancer outside the brain is more than 6 months - You can complete memory and thinking tests in English - Any prior brain treatments (like radiosurgery or surgery) were completed at least 7–14 days ago **You may NOT be eligible if...** - Your cancer started in the blood or the brain/spine itself (e.g., leukemia, brain tumor) - You have cancer spreading along the lining of the brain - You cannot have an MRI with contrast dye - You have had whole-brain radiation before - You have been previously diagnosed with dementia - You are pregnant or not using contraception - English is not your primary language Talk to your doctor to see if this trial is right for you.