Short-course Radiotherapy Followed by CAPOX and Ivonescimab for Locally Advanced Rectal Cancer

Inclusion Criteria: * ECOG score of 0-1; * histologically or cytologically confirmed colorectal adenocarcinoma with non-distant metastasis * Tumor distance from anal verge ≦10cm * at least one high-risk criterion defined by pelvic MRI: cT stage \>T2 (tumor invades intrinsic muscularis propria by more than 5 mm); Extramural vascular invasion; cN2; Involvement of the rectal mesorectal fascia (tumor or lymph node ≤1mm from the rectal mesorectal fascia); Lateral lymph node short diameter ≥5mm * enough organ function Exclusion Criteria: * with known MSI-H or dMMR * Multiple primary adenocarcinomas * History of pelvic radiotherapy * Previous immunotherapy, including immune checkpoint inhibitors (e.g., anti-PD-1 antibody, anti-PD-L1 antibody, anti-CTLA-4 antibody, etc.), immune checkpoint agonists (e.g., ICOS, CD40, CD137, GITR, OX40 antibody, etc.), immunocellular therapy, and other treatments targeting the immune mechanism of the tumor.