Safety and efficacy of underwater endoscopic mucosal resection for 10-20 mm colorectal serrated lesions (SEA CLEAR study).

BACKGROUND AND AIMS: Colorectal serrated lesions (SLs) are precursors of colorectal carcinoma via the serrated neoplasia pathway. However, the success rate of endoscopic resection of large SLs is low. Therefore, this study aimed to determine the safety and efficacy of underwater endoscopic mucosal resection (UEMR) for SLs sized 10-20 mm. METHODS: This two-center prospective observational study included patients with at least one SL sized 10-20 mm. We resected the SLs by UEMR and performed tattooing at the resection site. Surveillance colonoscopy was performed 12 months postoperatively to evaluate local recurrence. The primary outcome was the complete resection rate of UEMR, which was defined as en bloc resection with no serrated tissue in the four marginal biopsies and histologically negative margins. RESULTS: UEMR was performed for 65 SLs in 58 patients, with a median lesion size of 14 mm. The en bloc, R0 resection, and complete resection rates were 87.7% (57/65), 61.5% (40/65), and 60.0% (39/65), respectively. Adverse events included 1 (1.5%) immediate bleeding and 1 (1.5%) delayed perforation. Surveillance colonoscopy was performed in 50 patients with 57 scars, and the rates of identification for tattoos and scars were 94.7% (54/57) and 100% (57/57), respectively. The recurrence rate was 5.3% (3/57), and all three recurrent lesions were completely resected endoscopically. CONCLUSIONS: This two-center prospective study demonstrated that UEMR for SLs sized 10-20 mm was comparable to previous conventional endoscopic mucosal resection outcomes.

Comparison of the efficacy and tolerability of elobixibat plus sodium picosulfate with magnesium citrate and split-dose 2-L polyethylene glycol with ascorbic acid for bowel preparation before outpatient colonoscopy: a study protocol for the multicentre, randomised, controlled E-PLUS trial.

BACKGROUND: Sodium picosulfate (SP)/magnesium citrate (MC) and polyethylene glycol (PEG) plus ascorbic acid are recommended by Western guidelines as laxative solutions for bowel preparation. Clinically, SP/MC has a slower post-dose defaecation response than PEG and is perceived as less cleansing; therefore, it is not currently used for major bowel cancer screening preparation. The standard formulation for bowel preparation is PEG; however, a large dose is required, and it has a distinctive flavour that is considered unpleasant. SP/MC requires a small dose and ensures fluid intake because it is administered in another beverage. Therefore, clinical trials have shown that SP/MC is superior to PEG in terms of acceptability. We aim to compare the novel bowel cleansing method (test group) comprising SP/MC with elobixibat hydrate and the standard bowel cleansing method comprising PEG plus ascorbic acid (standard group) for patients preparing for outpatient colonoscopy. METHODS: This phase III, multicentre, single-blind, noninferiority, randomised, controlled, trial has not yet been completed. Patients aged 40-69 years will be included as participants. Patients with a history of abdominal or pelvic surgery, constipation, inflammatory bowel disease, or severe organ dysfunction will be excluded. The target number of research participants is 540 (standard group, 270 cases; test group, 270 cases). The primary endpoint is the degree of bowel cleansing (Boston Bowel Preparation Scale [BBPS] score ≥ 6). The secondary endpoints are patient acceptability, adverse events, polyp/adenoma detection rate, number of polyps/adenomas detected, degree of bowel cleansing according to the BBPS (BBPS score ≥ 8), degree of bowel cleansing according to the Aronchik scale, and bowel cleansing time. DISCUSSION: This trial aims to develop a "patient-first" colon cleansing regimen without the risk of inadequate bowel preparation by using both elobixibat hydrate and SP/MC. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCT; no. s041210067; 9 September 2021; https://jrct.niph.go.jp/ ), protocol version 1.5 (May 1, 2023).

Management of colorectal high-grade dysplasia or cancer resected by cold snare polypectomy: a multicenter exploratory study.

BACKGROUND: The clinical course and surveillance strategy for patients who undergo cold snare polypectomy (CSP) for high-grade dysplasia (HGD) or cancer is unclear. We investigated the management of colorectal HGDs and cancers following CSP. METHODS: This Japanese nationwide multicenter exploratory study was retrospectively conducted on patients who had undergone CSP for colorectal HGDs or cancers and follow-up colonoscopy at least once from 2014 to 2020. We investigated the detection rate of CSP scars, local recurrence rate (LRR), risk factors for local recurrence, and follow-up strategy. This study was registered with the University Hospital Medical Information Network (UMIN) Clinical Trials Registry (UMIN000043670). RESULTS: We included 155 patients with 156 lesions. CSP scars were identified in 22 (31.4%), 41 (54.7%), and 10 (90.9%) patients with curative, borderline, and non-curative resection, respectively. Among them, residual tumors were observed in one (4.5%), six (14.6%), and three (30.0%) cases, respectively. The total LRR was 13.7% (95% confidence interval: 6.8-23.8). R1 resection cases (either horizontal or vertical margins positive for tumors) were associated with local recurrence (p = 0.031). Salvage endoscopic and surgical resections were performed on 21 and 10 patients, respectively. Among them, the proportion of endoscopically suspected residual tumors was significantly higher (p < 0.001) in the residual tumor-positive group (100%) than in the residual tumor-negative group (28.6%). CONCLUSIONS: LRR after CSP for HGDs or cancers was 13.7% based on scar-identified cases. Salvage endoscopic or surgical resection should be performed according to the curability of the lesion and endoscopic findings during colonoscopic surveillance.

Diagnostic performance for T1 cancer in colorectal lesions ≥10 mm by optical characterization using magnifying narrow-band imaging combined with magnifying chromoendoscopy; implications for optimized stratification by Japan Narrow-band Imaging Expert Team classification.

BACKGROUND: Magnifying narrow-band imaging (M-NBI) and magnifying chromoendoscopy (M-CE) enable accurate diagnosis of T1 colorectal cancer, but the diagnostic yields from combined M-NBI and CE have not been fully analyzed. We aimed to evaluate the diagnostic yield of combining Japan NBI Expert Team (JNET) classification using M-NBI and M-CE. METHODS: Superficial colorectal lesions ≥10 mm removed at a Japanese tertiary cancer center between February 2016 and December 2018 were included. We analyzed the relationship between JNET classification, M-CE findings, and histological results based on prospectively collected endoscopic and pathologic data. RESULTS: A total of 1573 lesions, including 56 superficial submucosal invasive cancers, 160 deep submucosal invasive cancers, and 81 advanced cancers (≥T2) were analyzed. The probability of deeply invasive cancer (95% confidence interval) was 1.8% (1.1-2.8), 30.1% (25.4-35.1), and 96.6% (91.5-99.1) in JNET Types 2A, 2B, and 3, respectively. The probability of deeply invasive cancer in JNET Type 2B lesions with non-V, VL, and VH pit pattern was 4.3%, 16.6%, 76.0%, respectively (P < 0.001). CONCLUSIONS: Our study showed the stratification by M-NBI using JNET classification and the effect of additional M-CE for JNET Type 2B lesions.

Can Advanced Endoscopic Imaging Help Us Avoid Surgery for Endoscopically Resectable Colorectal Neoplasms? A Proof-of-Concept Study.

BACKGROUND: European guidelines recommend advanced endoscopic imaging (AEI) to guide therapeutic decisions; however, data are limited concerning its clinical effects on the management of colorectal polyps. The aim of this study was to investigate the effect of standard chromoendoscopic imaging (SCI) and AEI on decision-making regarding therapeutic techniques. METHODS: We retrospectively analyzed prospectively collected endoscopic and pathological data on colorectal neoplasms ≥ 10 mm removed at a Japanese tertiary cancer center between January 2010 and December 2016. We assumed a virtual approach to manage the decisions for endoscopic resection or surgery for each lesion using the following test modalities: (1) endoscopic size measurement (ESM), (2) SCI, and (3) AEI. Virtual surgical management was indicated using the following criteria: (1) ESM: lesion ≥ 40 mm, (2) SCI: depression, excavation, or ulceration, (3) AEI: Japan NBI Expert Team type 3 (magnifying NBI), VI high-grade, or VN (magnifying chromoendoscopy). We compared the incidence of hypothetical redundant surgery, defined as virtual surgical management for cases of dysplasia or superficial submucosal invasive cancers (SM-S). RESULTS: A total of 3509 lesions from 2693 patients were analyzed, including 142 SM-S and 457 deep submucosal invasive cancer (SM-D). The incidence of hypothetical redundant surgery was 9.2% with ESM, 5.1% with SCI, and 2.9% with AEI. When compared with ESM, hypothetical redundant surgery was significantly reduced with SCI (relative risk 0.55; 95% confidence interval 0.44-0.69) and AEI (0.31; 0.23-0.41). CONCLUSIONS: Therapeutic decision-making according to SCI or AEI can reduce surgery for endoscopically resectable colorectal neoplasms.