Clinical Research Directory

Inclusion Criteria: * 1\. Participants aged 18 years or older, regardless of gender. * 2\. Tumor located in the rectum, ≤10 cm from the anal verge. * 3\. Histologically confirmed adenocarcinoma, with pMMR by immunohistochemistry or MSS by genetic testing. * 4\. Clinical stage cT3-4N0/+M0. * 5\. ECOG PS 0-1. * 6\. Adequate function of major organs and bone marrow. * 7\. No contraindications to surgery. * 8\. Good compliance and willingness to complete subsequent follow-up. * 9\. Voluntary participation in this study and signed informed consent form. Exclusion Criteria: * 1\. Prior use of PD-1, PD-L1 or other immune checkpoint inhibitors. * 2\. Prior receipt of any anti-tumor therapy for colorectal cancer, including radiotherapy, chemotherapy, or tumor resection. * 3\. Microsatellite instability-high (MSI-H) or deficient mismatch repair (dMMR). * 4\. Presence of peritoneal metastasis or metastasis to other distant organs. * 5\. Participation in another anti-tumor investigational drug clinical trial within 4 weeks prior to enrollment. * 6\. History of hypersensitivity to any components of monoclonal antibodies, tislelizumab, capecitabine, or oxaliplatin. * 7\. Confirmed immunodeficiency disease or active autoimmune disease, including but not limited to systemic lupus erythematosus, inflammatory bowel disease, myasthenia gravis, autoimmune hepatitis, rheumatoid arthritis, multiple sclerosis, glomerulonephritis, vasculitis, etc.; use of other immunosuppressants or systemic corticosteroids for immunosuppressive purposes within 4 weeks prior to enrollment. * 8\. Known human immunodeficiency virus (HIV) infection; known clinically significant liver disease, including viral hepatitis \[active HBV infection (HBV DNA ≥2000 IU/mL or 10⁴ copies/mL), hepatitis C (positive anti-HCV antibody with HCV RNA above the assay lower limit of detection)\]. * 9\. Diseases associated with high bleeding risk such as gastrointestinal hemorrhage, bleeding diathesis, or thromboembolic diseases requiring long-term oral anticoagulants or anti-platelet agents. * 10\. Uncontrolled cardiac clinical signs or diseases, including but not limited to: a) NYHA class II or higher heart failure; b) unstable angina; c) myocardial infarction within the past 1 year; d) clinically significant supra-ventricular or ventricular arrhythmia that is untreated or poorly controlled after clinical intervention. * 11\. Severe infection (CTCAE grade \>2) within 4 weeks prior to the first dose of study drug, such as severe pneumonia requiring hospitalization, bacteremia, infectious complications, etc.; active pulmonary inflammation indicated on baseline chest imaging; active tuberculosis infection identified by medical history or CT scan, history of active tuberculosis within 1 year before enrollment, or history of active tuberculosis \>1 year previously without adequate treatment. * 12\. Diagnosis of another malignancy within 5 years before the first dose of study drug, except for malignancies with low risk of metastasis or death (5-year survival rate \>90%), such as adequately treated basal cell carcinoma or squamous cell carcinoma of the skin, or carcinoma in situ of the cervix. * 13\. Pregnant or lactating women. * 14\. Vulnerable populations other than the elderly or illiterate subjects, including patients with psychiatric disorders, cognitive impairment, critically ill patients, etc. * 15\. Other conditions that, in the investigator's judgment, may force premature termination of study participation.