Contrast-Enhanced Photon-Counting Detector CT (PCD-CT) for the Local Staging of Rectal Cancer

This study is testing a new type of CT scan (using photon-counting detector technology) to see how accurately it can stage rectal cancer — meaning how well it can tell doctors how far the cancer has spread locally — compared to standard MRI. **You may be eligible if...** - You are between 18 and 99 years old - You have a confirmed diagnosis of rectal cancer and are scheduled for standard staging scans (MRI and CT) - Your tumor is at least 2 cm in size - You are willing and able to sign a consent form - If you could be pregnant, you have had a negative pregnancy test **You may NOT be eligible if...** - You cannot receive intravenous contrast dye (e.g., due to severe allergy or kidney problems) - You are pregnant Talk to your doctor to see if this trial is right for you.