Clinical Outcomes After Non-curative Endoscopic Resection in Early Colorectal Cancer: A Multicenter Study

Inclusion criteria

• Age ≥18 years;
• Patients with early colorectal cancer confirmed by histopathology;
• Patients who underwent endoscopic resection (including EMR, ESD, or equivalent techniques);
• Pathological diagnosis indicating non-curative resection, defined by the presence of at least one of the following: positive resection margin, submucosal invasion depth >1000 μm, poor differentiation, lymphovascular invasion, perineural invasion, or high-grade tumor budding;
• Availability of complete clinicopathological and follow-up data;
• Patients managed with either additional surgery or surveillance after endoscopic resection.

Exclusion criteria

• Patients with synchronous advanced colorectal cancer or distant metastasis at baseline;
• History of other active malignancies;
• Patients with inflammatory bowel disease, familial adenomatous polyposis, or other hereditary colorectal cancer syndromes;
• Patients who received neoadjuvant therapy before endoscopic resection;
• Incomplete pathological data or missing key variables;
• Loss to follow-up or follow-up duration less than 6 months.