Neoadjuvant Chemotherapy and PD-1 Inhibitor for Locally Advanced Rectal Cancer

Receive the experimental combination of drugs (chemoradiation (Oxaliplatin and Capecitabine) + PD-1 inhibitor (Tislelizumab) 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 to four years. The time in the study will take approximately four - six hours during pre-study, study and end of study visits.