Oral Chemotherapy, Targeted Therapy and Immunotherapy With/Without Radiotherapy as 3rd- or Later-line Therapy for Advanced MSS/pMMR Colorectal Cancer

This trial is testing a combination of oral therapies — chemotherapy, targeted therapy, and immunotherapy — with or without radiation for people with advanced colorectal cancer that is MSS/pMMR (a subtype that typically does not respond to standard immunotherapy) who have progressed after at least two prior lines of treatment. **You may be eligible if...** - You are 18 or older - You have advanced colorectal adenocarcinoma confirmed as MSS/pMMR by testing - You have already received and progressed on standard treatments including oxaliplatin, irinotecan, and fluorouracil - You are in good health (ECOG 0–1) - You can take oral medications - You are expected to live at least 3 more months - You have measurable disease with ≤2 affected organs, maximum lesion size ≤5 cm, and ≤10 total lesions **You may NOT be eligible if...** - Your cancer has not been confirmed as MSS/pMMR - You have not tried at least two prior lines of standard therapy - You have too many or too large tumor lesions to meet study criteria Talk to your doctor to see if this trial is right for you.