Toripalimab Combined With Neoadjuvant Chemoradiotherapy as First-line Treatment for Locally Advanced，High-Risk，MSS Rectal Cancer
This is a single arm, open-label, prospective clinical trial to evaluate the combination of neoadjuvant short-course radiotherapy and toripalimab (PD-1 antibody) for locally advanced rectal cancer (LARC) patients with high risk factors. A total of 53patients will be enrolled in this trial to receive 5\*5Gy short-course radiotherapy, followed by 4 cycles of CAPOX chemotherapy and PD-1 antibody. Then they will receive the TME surgery and another 2 cycles of CAPOX chemotherapy. The primary end point is the rate of pathological complete response (pCR). The long-term prognosis and adverse effects will also be evaluated and analyzed.
• Age 18-75 years old, female and male;
• Pathological confirmed MSS or pMMR rectal adenocarcinoma;
• Clinical stage T3-4 (AJCC 8th) and at least with one high risk factor（CRM+ or EMVI+ or lateral lymph nodes+）;
• No previous chemotherapy, radiotherapy, immunotherapy or other anti-tumor treatment;
• Adequate organ function defined at baseline as:
‣ ANC ≥1.5××109/L，PLt ≥100×109 /L，Hb ≥90 g/L，15×109 /L≥WBC≥4×109 /L; TBIL ≤1.5×ULN, ALT ≤1.5ULN, AST ≤1.5ULN, BUN and Cr ≤1.5×ULN or Ccr
• 60ml/min (Cockcroft-Gault formula);INR ≤1.5×ULN or PT ≤1.5×ULN (when patient didn't accept anticoagulant therapy);
⁃ Women of childbearing age must have taken reliable contraceptive measures or have a pregnancy test (serum or urine) within 7 days prior to enrollment and the results are negative;