Clinical Research Directory

Inclusion Criteria: 1. Age ≥18 years and ≤75 years 2. Histologically confirmed adenocarcinoma of the rectum 3. pMMR (proficient mismatch repair) or MSI-L (microsatellite instability-low) or MSS (microsatellite stable) 4. Tumor distance from the anal verge ≤5 cm 5. Clinical stage of cT1-3N1M0 or cT2-3N0M0 6. ECOG performance status score ≤ 1 Exclusion Criteria: 1. Patients with metastatic disease (Stage IV); recurrent colorectal cancer with active bleeding, perforation, or complex conditions requiring urgent surgery; or concurrent non-colorectal cancer malignancies. 2. Patients who have previously received systemic anticancer therapy for colorectal cancer; or have been treated with PD-1, PD-L1, or CTLA-4 antibodies. 3. Patients with any active autoimmune disease; known or tested positive for Human Immunodeficiency Virus (HIV) or Acquired Immunodeficiency Syndrome (AIDS); or a history requiring steroid or immunosuppressive drug treatment. 4. Patients with interstitial lung disease, non-infectious pneumonitis, or uncontrolled systemic diseases (such as diabetes, hypertension, pulmonary fibrosis, and acute pneumonia). 5. Patients who experienced any Grade 2 or higher toxicities due to prior treatments (as classified by the Common Terminology Criteria for Adverse Events \[CTCAE\] version 5), which have not resolved (excluding anemia, alopecia, and skin pigmentation changes); known or suspected history of hypersensitivity to any of the drugs used in the trial. 6. Pregnant or breastfeeding women.