FDG PET-CT in Advanced Breast Cancer

This study is evaluating the use of FDG PET-CT scans (a special type of imaging that shows cancer activity) to track treatment responses in people with advanced or metastatic breast cancer. It aims to see whether PET-CT gives better or earlier information about whether treatments are working compared to standard CT scans. **You may be eligible if...** - You are 19 or older with metastatic or locally advanced breast cancer - You are about to start a new systemic treatment (hormone therapy, chemotherapy, targeted therapy, or immunotherapy) - You are willing and able to attend repeated imaging appointments - You are in reasonable physical condition (ECOG 0–2) **You may NOT be eligible if...** - You have already started or previously received treatment for advanced breast cancer - You are unwilling or unable to complete follow-up imaging visits Talk to your doctor to see if this trial is right for you.