Project description:Background/aimsThere are few prospective studies on cold forceps polypectomy (CFP) using jumbo cup forceps. Therefore, we examined patients with diminutive polyps (5 mm or smaller) treated with CFP using jumbo cup forceps to achieve an adenoma-free colon and also assessed the safety of the procedure and the recurrence rate of missed or residual polyp after CFP by performing follow-up colonoscopy 1 year later.MethodsWe included patients with up to 5 adenomas removed at initial colonoscopy and analyzed data from a total of 361 patients with 573 adenomas. One-year follow-up colonoscopy was performed in 165 patients, at which 251 lesions were confirmed.ResultsThe one-bite resection rate with CFP was highest for lesions 3 mm or smaller and decreased significantly with increasing lesion size. Post-procedural hemorrhage was observed in 1 of 573 lesions (0.17%). No perforation was noted. The definite recurrence rate was 0.8% (2/251 lesions). The probable recurrence rate, which was defined as recurrence in the same colorectal segment, was 17%. Adenoma-free colon was achieved in 55% of patients at initial resection. Multivariate analysis revealed that achievement of an adenoma-free colon was significantly associated with number of adenomas and years of endoscopic experience.ConclusionsCFP using jumbo biopsy forceps was safe and showed a high one-bite resection rate for diminutive lesions of 3 mm or smaller. The low definite recurrence rate confirms the reliability of CFP using jumbo biopsy forceps. Number of adenomas and years of endoscopic experience were key factors in achieving an adenoma-free colon.
Project description:Background and study aims Small colorectal polyps are removed by various methods, including cold snare polypectomy (CSP), hot snare polypectomy (HSP), and underwater endoscopic mucosal resection (UEMR), but the indications for using these methods are unclear. We retrospectively assessed the efficacy of CSP, HSP, and UEMR for small polyps, focusing on the depth of the resected specimens. Patients and methods Outpatients with non-pedunculated small polyps (endoscopically diagnosed as 6 to 9 mm), resected by two endoscopists between July 2019 and September 2020, were enrolled. We histologically evaluated the specimens resected via CSP, HSP, and UEMR. The main outcome was the containment rate of the muscularis mucosa (MM) and submucosa (SM) tissues. Results Forty polyps resected via CSP (n = 14), HSP (n = 12), or UEMR (n = 14) were enrolled after excluding 13 polyps with resection depths that were difficult to determine. The rates of specimens containing MM and SM tissue differed significantly (57 % and 29 % for CSP, 92 % and 83 % for HSP, and 100 % and 100 % for UEMR, respectively ( P = 0.005 for MM and P < 0.001 for SM tissue). Multiple logistic regression analysis showed UEMR was an independent factor relating to the containment of SM tissue. The thickness of SM tissue by CSP, HSP, and UEMR were 52 μm, 623 μm, and 1119 μm, respectively ( P < 0.001). The thickness by CSP was significantly less than those by HSP and UEMR ( P < 0.001, Bonferroni correction). Conclusions UEMR could be the best method to contain SM tissue without injection. Further studies are needed to evaluate the indication of UEMR for small polyps.
Project description:Interventions: experimenta group:Underwater cold snare polypectomy;control group:Cold trap polyp resection
Primary outcome(s): Biopsy results of the bottom and edge of the specimen
Study Design: Parallel
Project description:BackgroundColorectal cancer (CRC) screening is less effective at reducing cancer incidence in the proximal colon compared to the distal colorectum. We aimed to identify adenoma characteristics associated with proximal colon cancer (PCC).MethodsEndoscopy and pathology data for patients with ≥1 adenoma detected at baseline colonoscopy were obtained from 17 UK hospitals between 2001 and 2010. Multivariable Cox regression models were used to estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for PCC, and, for comparison, distal CRC incidence, by adenoma characteristics.ResultsAmong 18,431 patients, 152 and 105 developed PCC and distal CRC, respectively, over a median follow-up of 9.8 years. Baseline adenoma characteristics positively associated with PCC incidence included number (≥3 vs. < 3: aHR 2.10, 95% CI: 1.42-3.09), histology (tubulovillous/villous vs. tubular: aHR 1.61, 95% CI: 1.10-2.35) and location (any proximal vs. distal only: aHR 1.70, 95% CI: 1.20-2.42), for which there was borderline evidence of heterogeneity by subsite (p = 0.055). Adenoma dysplasia (high vs. low grade) was associated with distal CRC (aHR 2.42, 95% CI: 1.44-4.04), but not PCC (p-heterogeneity = 0.023).ConclusionsBaseline adenoma number, histology and proximal location were independently associated with PCC and may be important to identify patients at higher risk for post-polypectomy PCC.
Project description:Accidental bending of the snare sheath occasionally occurs during cold snare polypectomy (CSP). We aimed to demonstrate whether snare bending reduces resection ability and, if it does, what causes this reduction. Using currently available CSP snares and prototype snares, we investigated changes in the resection ability of bent snares as well as the stiffness of their sheaths and wire spindles. Furthermore, to evaluate the performance of the bent snares, we measured the completion rate of CSP for 5-mm-diameter pseudo-lesions on the porcine rectal mucosa. Snare bending significantly decreased resection ability and wire spindle stiffness. Compared with bending the snares once, bending the snares five times further decreased the resection ability and wire spindle stiffness. A strong correlation was observed between wire spindle stiffness and resection ability after snare bending (correlation coefficient = 0.82; P < 0.001). Additionally, snare bending reduced the completion rate of CSP. Bending a CSP snare causes decreased wire spindle stiffness, thereby reducing its resection ability and potentially lowering the resection completion rate. The resection ability cannot be restored; therefore, snare replacement is recommended.