Neoadjuvant Radiochemotherapy Combined With QL1706 for Low Rectal Cancer

Inclusion criteria

• Patients willing to receive neoadjuvant therapy.
• Aged 18-75 years, regardless of gender.
• Diagnosed with low-lying rectal adenocarcinoma (tumor located ≤7 cm from the anal verge) via colonoscopy, endorectal ultrasound, and pelvic high-resolution MRI, without distant metastasis.
• Histopathologically confirmed rectal adenocarcinoma.
• Good patient compliance, able to attend follow-up visits as required.
• ECOG performance status score of 0-1.
• Laboratory tests meeting the following criteria:

i. WBC ≥3.5×10^9/L, ANC ≥1.8×10^9/L, platelets ≥100×10^9/L, hemoglobin ≥100 g/L.

ii. INR ≤1.5, APTT ≤1.5×ULN, or PTT ≤1.5×ULN. iii. Total bilirubin ≤1.25×ULN; ALT/AST ≤5×ULN. iv. 24-hour creatinine clearance ≥50 mL/min or serum creatinine ≤1.5×ULN.

• Voluntary signed informed consent.

Exclusion criteria

• History of malignant colorectal tumors.
• Patients requiring emergency surgery (e.g., intestinal obstruction, perforation, or hemorrhage).
• Known allergy to capecitabine, oxaliplatin, PD-L1 inhibitors, CTLA-4 inhibitors, or related drugs.
• Histopathology indicating poorly differentiated adenocarcinoma or signet ring cell carcinoma.
• Unstable systemic diseases, including but not limited to:

Severe infection, uncontrolled diabetes, refractory hypertension, unstable angina, cerebrovascular accident, myocardial infarction, congestive heart failure, life-threatening arrhythmias, or severe hepatic/renal/metabolic disorders.

• Conditions (e.g., psychiatric disorders, substance abuse) that may increase treatment risk, compromise compliance, or confound study results.
• Participation in another interventional clinical trial or use of investigational drugs within 30 days prior to screening.
• Pregnancy, lactation, or refusal to use effective contraception during the study.
• Other conditions deemed unsuitable by the investigator.