Neoadjuvant Tisleizumab(BGB-A317) for dMMR/MSI-H Non-late Stage Colorectal Cancer Patients

According to the cancer statistics in 2020, colorectal cancer (CRC) remains a major public health issue worldwide, representing the third common cancer (10%) and second leading cause of death (9.4%) with 5-year survival rate approaching 65%. Meanwhile, 28.8% of the newly diagnosed cases and 30.3% of the CRC-related death occurs in China. Among all the CRC, stage I-III account for 75%. For the standard management for non-late stage(stage I-III) CRC patients, surgery including the primary site and local lymph nodes dissection has been the most important one. But for the high-risk stage II and locally-advanced stage III CRC, neoadjuvant or adjuvant therapy such as chemotherapy and radiotherapy plays a vital role in preventing the residual cancer cells to relapse and spread to distant sites after surgery. For the past decades, immunotherapy like anti-PD-1 and anti-CTLA4 checkpoint inhibitor achieves great process in solid tumor treatment especially for late-stage CRC. And Pembrolizumab and Nivolumab has been proved for dMMR/MSI-H late-stage-CRC by FDA. Combination of Ipilimumab and Nivolumab has achieved great success among the early-stage-CRC in NICHE study. The investigators here to carry out a phase II clinical trial to explore the safety and effect of single anti-PD-1 (Tisleizumab-BGB-A317 ) neoadjuvant treatment for non-late stage CRC patients.