Adenomatous Polyps

This is a retrospective and prospective cohort study designed to evaluate the recurrence rate and identify risk factors after endoscopic resection of gastric and intestinal polyps. BACKGROUND: Gastric and intestinal polyps are common digestive diseases with potential for malignant transformation. Although endoscopic resection is the standard treatment, recurrence rates range from 10-50%, and the mechanisms and risk factors remain unclear. OBJECTIVES: Primary: To assess short-term (1-year) and long-term (3-year) recurrence rates after endoscopic polyp resection Secondary: To identify independent risk factors and develop a recurrence risk prediction model DESIGN: Mixed retrospective-prospective cohort study * Retrospective cohort: Patients who underwent polyp resection from 2021-2022, with follow-up data through 2024 * Prospective cohort: Patients enrolled from 2024-2025, with standardized follow-up through 2028 SETTING: Single tertiary referral center with \>10,000 endoscopic polyp resections performed since 2021 PARTICIPANTS: Approximately 1,600-1,800 adult patients (≥18 years) who underwent complete endoscopic resection of gastric or intestinal polyps FOLLOW-UP: * Short-term: 1 year post-resection (±2 months) * Long-term: 3 years post-resection (±3 months) MAIN OUTCOME: Recurrence rate defined as new polyp detection at original or different sites during endoscopic surveillance POTENTIAL RISK FACTORS: Patient demographics, polyp characteristics (size, number, location, pathology), resection method, Helicobacter pylori status, lifestyle factors, and medication use EXPECTED IMPACT: Results will inform personalized surveillance strategies and optimize resource allocation for post-polypectomy follow-up.

Detection and removal of polyps during colonoscopy is crucial for the prevention of colorectal cancer. Indigo carmine spraying up to the colonic mucosa could probably increase the adenoma detection rate, but considering the long withdrawal time of the endoscope and the resulting increase in time and cost. Linked-color imaging (LCI) is a newly developed image-enhanced endoscopy technology. It relies on wave length optimization of three colors (red, green, and blue) to make the lesions appear fuller. LCI improves the visibility of colorectal adenomas and polyps and may increase the detection rate of lesions. In order to explore the clinical application value of Linked-color imaging endoscopy, we performed a prospective, randomized controlled trial to compare adenoma detection rate of Linked-color imaging endoscopy and indigo carmine chromoendoscopy.

Colorectal cancer (CRC) has become the third most common malignant tumor and is the second leading cause of cancer related deaths worldwide. Adenomatous polyps of the colon are possible precursor lesions for CRC. Screening for CRC has been shown effective in preventing CRC and related deaths, especially colonoscopy and resection of adenomatous polyps. Currently, for intermediate sized polyps 5 - 19 mm hot snare polypectomy (HSP) with the use of electrocautery is conventionally used, causing relevant adverse events including haemorrhage and postpolypectomy coagulation syndrome, but is safe regarding complete resection of the polyp due to burning effect on residual tissue. On the other hand, cold snare polypectomy (CSP) has grown popularity. Absence of electrocautery makes it technically easier and most important reduces adverse events. CSP is recommended as the preferred technique for polyps \<5 mm by the European Society of Gastrointestinal Endoscopy (ESGE) guidelines. In literature, there is one multicenter trial from Japan recommending CSP for polyps 4-9 mm (average polyp size 5,4 mm) and only a few case studies for polyps 10-15 mm with inconsistent results, especially regarding the complete resection and pathological evaluation of the specimen. In this randomized controlled trial, the investigators want to compare the complete resection rates of small and intermediate sized colorectal polyps 10-15 mm with CSP and HSP.

The primary objective of the study is to screen multi-omics markers in blood samples and construct a prediction model for CRC based on liquid biopsy, and we will further optimize the prediction model by validating its clinical performance externally.