Regorafenib Alone or in Combination With Hypofractionated/Low-dose Radiotherapy Plus Toripalimab for Metastatic Colorectal Cancer

This study is testing a combination of regorafenib (a targeted cancer drug), low-dose radiation therapy, and toripalimab (an immunotherapy drug that helps the immune system attack cancer) for patients with metastatic colorectal cancer (cancer that has spread) that has not responded to previous treatments. **You may be eligible if...** - You are 18 or older with confirmed colorectal cancer that has spread - Your cancer is MSS/pMMR type (a molecular classification) - You have at least one tumor site suitable for radiation - Your overall health is adequate for treatment (ECOG 0–1, life expectancy at least 3 months) - You have already received standard chemotherapy regimens **You may NOT be eligible if...** - Your cancer has not been treated with standard chemotherapy first - You have autoimmune disease or are on immune-suppressing medications - You have untreated brain metastases - Your organ function is too poor for chemotherapy or radiation Talk to your doctor to see if this trial is right for you.