Extent of Lymph Node Dissection for Advanced Right-Sided Colon Cance

Inclusion Criteria: 1. Age: 18-75 years 2. Preoperative pathologic confirmation of adenocarcinoma 3. Tumor located in the region from the ileocecal valve to the right one-third of the transverse colon 4. American Society of Anesthesiologists (ASA) physical status classification I to III 5. Patients who have not received preoperative radiotherapy, chemotherapy, or immunotherapy 6. Preoperative imaging staging cT4N0M0 or cT3-4N+M0 7. Willing to participate in the study and sign the informed consent form Exclusion Criteria: 1. Past medical history of malignant tumor 2. Patients with multiple primary tumors 3. Patients with a history of inflammatory bowel disease or familial adenomatous polyposis 4. Patients with distant metastasis 5. Pregnant or breastfeeding women 6. History of other previous major abdominal surgery 7. Patients requiring emergency surgery (including tumor perforation, obstruction, hemorrhage, etc.) 8. Those with other clinical and laboratory conditions deemed by the investigator to be inappropriate for participation in the trial