The goal of this clinical trial is to evaluating the efficacy and safety of radiotherapy combined with Tislelizumab, Liposomal Irinotecan, and Capecitabine in patients with locally advanced mid-lower rectal cancer with pMMR.. Patients would be included as:1. Aged between 18-75 years, with no gender restrictions; 2. Biopsy pathology confirmed as pMMR type locally advanced mid-lower rectal adenocarcinoma (tumor lower margin ≤ 10 cm from the anal verge); 3.With the following high-risk factors: T3N+/T4/N2/EMVI+/MRF+/lateral lymph node metastasis/inability to preserve anal function during surgery; 4. No distant metastasis observed in routine chest and abdominal CT scans.
Age: 18-75 years, no gender restriction
ECOG score 0-1
Biopsy-confirmed pMMR (proficient mismatch repair) localized advanced low rectal adenocarcinoma (tumor's lower edge ≤ 10 cm from the anus)
Presence of the following high-risk factors: T3N+/T4/N2/EMVI+/MRF+/lateral lymph node metastasis/inability to undergo sphincter-preserving surgery
Patients with a history of other malignancies within the past 5 years (except for cured and non-recurring cancers such as in situ carcinoma, basal cell carcinoma of the skin, etc.)
Patients with active, uncontrolled bacterial, viral, or fungal infections requiring systemic treatment, defined by persistent signs/symptoms related to infection, which do not improve despite appropriate antibiotics, antiviral treatments, and/or other therapies
Patients with uncontrolled systemic diseases, including unstable angina, myocardial infarction, congestive heart failure, severe unstable ventricular arrhythmia, history of severe pericardial disease, or other cardiovascular diseases; uncontrolled hypertension (defined as systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg despite appropriate antihypertensive treatment), or a history of hypertensive crisis, hypertensive encephalopathy; uncontrolled diabetes (fasting blood glucose ≥ 10 mmol/L), etc.
Patients known to be allergic or intolerant to the treatment drugs or excipients used in this study