Can Endoscopic Resection Alone Provide Definitive Management for High-Risk Adenomatous Polyps?

Objective Adenomatous polyps with high-grade dysplasia or intramucosal carcinoma are generally managed endoscopically, while lesions with deeper invasion typically require radical resection. This study aimed to provide clinically relevant information to support colorectal cancer prevention by examining the relationships among demographic, clinical, and histopathological features and performing risk stratification of patients with detected high-risk polyps. Methods This retrospective multicenter study included 128 patients with high-risk adenomatous polyps treated between January 2006 and September 2025 at two tertiary referral centers. Patients were categorized according to polyp morphology as sessile, pedunculated, or mixed-morphology. Clinicopathological characteristics, treatment modalities, and follow-up data were analyzed. High-risk polyps were defined according to histopathological features associated with advanced neoplasia and potential residual disease risk. Results Of the 128 patients, 55 (43.0%) had sessile, 49 (38.3%) had pedunculated, and 24 (18.8%) had mixed high-risk polyps. Age, maximum polyp size, follow-up duration, and sex distribution were comparable across the three groups, whereas rectal location, excision technique, en bloc resection, and piecemeal resection differed significantly according to polyp morphology. In multivariable analysis, positive resection margin was the only independent factor associated with radical surgery, whereas piecemeal resection, invasive adenocarcinoma histology, and rectal location were independently associated with margin positivity. No local recurrence or distant metastasis occurred during follow-up. Conclusions High-risk adenomatous polyps can be safely managed without radical surgery if complete en bloc excision and low-risk pathological features are present. Under close surveillance, minimally invasive endoscopic procedures offer effective treatment for selected patients.