To evaluate the safety and preliminary efficacy of preoperative chemotherapy and PD-1 inhibitor Tislelizumab for Rectal Cancer patients.Go through laboratory and medical tests to verify eligibility to enter the study, receive the experimental combination of drugs CAPOX (Oxaliplatin and Capecitabine) for 3 cycles prior to surgery and undergo laboratory tests and study procedures on specified days during the study period, complete end of study evaluations and tests, and participate in post-study follow up every three months for three years.
Be willing and able to provide written informed consent for the trial
Age 18 years or greater
Pathologically proven diagnosis of adenocarcinoma of the rectum
Clinically determined to be stage T3 or T4, N0-N2, and M0
Age less than 18 years
Pregnant or breastfeeding women
Prior invasive malignancy unless disease free for a minimum of three years
Preoperative body temperature ≥ 38°C or concurrent infectious diseases requiring systemic therapy;