Efficacy and Safety of Tislelizumab (BGB-A317) as Neo-Adjuvant Treatment in Participants With Colorectal Cancer

Inclusion Criteria: * Participants had an Eastern Cooperative Oncology Group (ECOG) Performance Status score of 0 or 1. * Participants had a pathologically (histologically) confirmed diagnosis of potentially resectable Stage II or Stage III colon or rectal cancer (CRC) with microsatellite instability-high (MSI-H) status confirmed by a sponsor-designated central laboratory, or known MSI-H status confirmed by a local laboratory. Participants were required to be eligible for complete surgical removal of the tumor (R0 resection) with curative intent. * Participants had evaluable or measurable disease as assessed by the investigator according to the Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1. * Participants had adequate blood counts and organ function, as defined by protocol-specified laboratory test results obtained within 7 days before the first dose of study treatment. Exclusion Criteria: * Participants had received any prior treatment for their current colorectal cancer, including chemotherapy, radiotherapy, or immunotherapy. * Participants had any condition requiring systemic treatment with corticosteroids at doses greater than 10 milligrams (mg) of prednisone per day, or other immunosuppressive medications within 14 days before the first dose. * Participants had active autoimmune diseases or a history of autoimmune diseases that could potentially relapse. Note: Additional protocol-defined inclusion and exclusion criteria may have applied.