Involved-field Radiotherapy-TNT Combined With PD-1 Inhibitor for pMMR Locally Advanced Rectal Cancer (Neo-Field I)

Inclusion Criteria

• •1. Age ≥18 years old, male or female;
• •2. Eastern Cooperative Oncology Group (ECOG) performance status of 0-1;
• •3. Pathologic diagnosis of adenocarcinoma of the rectum, definite pMMR type;
• •4. Clinical staging of T3-4NanyM0 or T1-2N+M0 (based on AJCC 8th edition staging criteria);
• •5. The lower margin of the primary tumor is located below the peritoneal reflex or the lower margin of the tumor is ≤10 cm from the anal verge;
• •6. Pre-enrollment laboratory indicators meet the following indicator ranges： 1)Blood: absolute neutrophils ≥1.5×10\^9/L, platelets ≥100×10\^9/L, hemoglobin ≥90g/L; 2)Liver and kidney function: ALT/AST ≤ 2.5 x ULN, total bilirubin ≤ 1.5 x ULN, creatinine ≤ 1.5 x ULN or creatinine clearance ≥ 60mL/min (Cockcroft-Gault formula)； 3)Coagulation: INR ≤ 1.5, APTT ≤ 1.5 x ULN (for those not receiving anticoagulation)；
• •7. Women or men of childbearing potential need to agree to use effective contraception during the study and for 6 months after the last treatment session;
• •8. Voluntary written informed consent and commitment to complete the full treatment and follow-up program.