This study aims to evaluate the use of node-sparing short-course radiotherapy combined with chemotherapy and Sintilimab, or chemotherapy alone, as neoadjuvant therapy for MSS-type locally advanced colon cancer. The goal is to explore the efficacy and safety of combining node-sparing short-course radiotherapy with chemotherapy and immunotherapy in the neoadjuvant setting for MSS-type locally advanced colon cancer, while also investigating the specific role of regional lymph nodes in tumor immunotherapy.
1. Patients willing to undergo neoadjuvant treatment. 2. Age ≥ 18 years. 3. Tumor confirmed by colonoscopy and enhanced abdominal CT to be ≥ 12 cm from the anal verge.
White blood cell count ≥ 3.5 × 10^9/L, absolute neutrophil count ≥ 1.5 × 10^9/L, platelet count ≥ 100 × 10^9/L, hemoglobin concentration ≥ 9 g/dL;
Liver function tests (bilirubin ≤ 1.5 × ULN; AST and ALT ≤ 5 × ULN);
Renal function (serum creatinine ≤ 1.5 × ULN or creatinine clearance (CCr) ≥ 50 mL/min);
1. History of other malignancies within the past 5 years. 2. Patients with metastases in other locations (stage IV). 3. Patients with MSI-H or dMMR. 4. Patients with conditions such as bowel obstruction, perforation, or bleeding requiring emergency surgery.
Parallel
Node-Sparing Short-Course Radiotherapy Combined with CAPOX and Sintilimab
DrugRadiotherapy Protocol: Short-course radiotherapy using three-dimensional conformal or intensity-modulated radiation therapy techniques. The radiation field will be limited to the tumor bed of the primary colon lesion, excluding surrounding draining lymph nodes and enlarged lymph nodes. The dose is fractionated as 5Gy per fraction, for a total of 25Gy over 5 fractions. Titanium clips will be placed on the proximal and distal ends of the colonic lesion via colonoscopy to guide radiation therapy positioning. Chemotherapy Protocol (CAPOX Regimen): 1. Oxaliplatin: 130 mg/m², administered intravenously (ivgtt), on day 1 (d1). 2. Capecitabine: 1000 mg/m², orally (po), twice daily (bid), from day 1 to day 14 (d1-14). Immunotherapy Protocol: During preoperative treatment, Sintilimab (immune checkpoint inhibitor) will be administered concurrently with each chemotherapy cycle.
CAPOX Chemotherapy
DrugParticipants will receive 4 cycles of CAPOX chemotherapy followed by radical total mesorectal excision surgery, and then 4 additional cycles of postoperative CAPOX chemotherapy.
pathological complete response rate
The tumor specimen from node-sparing neoadjuvant chemoradiotherapy combined with immunotherapy, followed by sequential CME (complete mesocolic excision) surgery, showed no presence of cancer cells or lymph node metastasis under microscopic examination (ypT0N0M0).
R0 resection rate
which is the percentage of patients who undergo a surgical procedure in which the tumor is completely removed with no cancer cells detected at the margins (edges) of the resected tissue. Achieving an R0 resection is a critical goal in cancer surgery, as it indicates that all visible and microscopic tumor cells have been removed, reducing the likelihood of recurrence.
Tumor downstaging rate
The tumor downstaging rate refers to the percentage of patients whose tumors decrease in size or extent (stage) following neoadjuvant treatment, compared to their initial stage at diagnosis. Downstaging means that the tumor has responded to treatment to the point where it moves from a more advanced stage (e.g., from stage III to stage II or I), which may improve the likelihood of successful surgical removal and lead to better prognosis.
The 3-year Event-Free Survival
The 3-year Event-Free Survival (EFS) refers to the percentage of patients who remain free from certain negative events-such as cancer progression, recurrence, or death-within three years after treatment. In clinical trials, EFS is a critical measure of a treatment's long-term efficacy, indicating how long patients can live without the disease worsening or other significant events occurring during the follow-up period.
Objective Response Rate
Objective Response Rate (ORR) refers to the percentage of patients in a clinical study whose cancer shows a measurable reduction in tumor size in response to treatment.
Click on the lead sponsor to view all of their trials.
This trial is not recruiting at the moment. You can still explore other options:
