A Series of Neoadjuvant Chemoradiotherapy Combined With Immunotherapy for Locally Advanced Rectal Cancer: From a Multicenter Phase II Cohort to a Phase III Randomized Controlled Study
The goal of this clinical trial is to compare the efficacy and safety of neoadjuvant chemoradiotherapy combined with tirelizumab compared with neoadjuvant chemoradiotherapy alone for neoadjuvant therapy in patients with locally advanced rectal cancer. The main questions it aims to answer are: To evaluate the efficacy and safety of neoadjuvant chemoradiotherapy combined with tirelizumab compared with neoadjuvant chemoradiotherapy alone for neoadjuvant therapy in patients with locally advanced rectal cancer To assess rectal or anal retention as well as quality of life. Participants will receive a long course of NCRT (50 Gy / 25f, capecitabine 850-1000 mg / m2, BID, PO, D1-D5, QW) within the first 5 weeks. In regard to tumor immunotherapy, enrolled patients will receive tislelizumab (200 mg, iv) on the first day at week 2,5, and 8 after initiation of radiotherapy. Thereafter, patients will be treated with two 14-day cycles of the CAPOX（Q 3 w; D1 oxaliplatin, 130mg/m2,iv.gtt; D1-D14, capecitabine, 850-1000mg / m2, BID, PO）regimen. Two CAOPX regimens were treated one week apart.
• Signed a written informed consent form and volunteered to join the study;
• .Age: 18-75 years old, male or female;
• Pathohistologically confirmed rectal adenocarcinoma, along with immunohistochemical results of pMMR or genetic test results of MSS;
• The baseline clinical stage assessed by MRI was T1-2N1-2M0 or T3N0-2M0, MRF (-), lateral lymph nodes (-);
• The lower tumor margin is 10cm away from the anal margin;
• Surgical resection;
• Ability to swallow tablets normally;
• ECOG PS 0-1；
• Have not received any anti-tumor treatment for rectal cancer, including radiotherapy, chemotherapy, surgery, etc.;
⁃ Plan to undergo surgery after the completion of the neoadjuvant therapy;
⁃ No contraindications to surgery;
⁃ Main organ function is normal.