Search

Objectives: There have been significant advances in the management of large (≥20 mm) laterally spreading tumors (LSTs) or nonpedunculated colorectal polyps; however, there is a lack of clear consensus on the management of these lesions with significant geographic variability especially between Eastern and Western paradigms. We aimed to provide an international consensus to better guide management and attempt to homogenize practices., Methods: Two experts in interventional endoscopy spearheaded an evidence-based Delphi study on behalf of the World Endoscopy Organization Colorectal Cancer Screening Committee. A steering committee comprising six members devised 51 statements, and 43 experts from 18 countries on six continents participated in a three-round voting process. The Grading of Recommendations, Assessment, Development and Evaluations tool was used to assess evidence quality and recommendation strength. Consensus was defined as ≥80% agreement (strongly agree or agree) on a 5-point Likert scale., Results: Forty-two statements reached consensus after three rounds of voting. Recommendations included: three statements on training and competency; 10 statements on preresection evaluation, including optical diagnosis, classification, and staging of LSTs; 14 statements on endoscopic resection indications and technique, including statements on en bloc and piecemeal resection decision-making; seven statements on postresection evaluation; and eight statements on postresection care., Conclusions: An international expert consensus based on the current available evidence has been developed to guide the evaluation, resection, and follow-up of LSTs. This may provide guiding principles for the global management of these lesions and standardize current practices., (© 2024 The Authors. Digestive Endoscopy published by John Wiley & Sons Australia, Ltd on behalf of Japan Gastroenterological Endoscopy Society.)

Background and Aim: Recently, the BLI Adenoma Serrated International Classification (BASIC) system was developed by European experts to differentiate colorectal polyps. Our aim was to validate the BASIC classification system among the US-based endoscopy experts., Methods: Participants utilized a web-based interactive learning system where the group was asked to characterize polyps using the BASIC criteria: polyp surface (presence of mucus, regular/irregular and [pseudo]depressed), pit appearance (featureless, round/non-round with/without dark spots; homogeneous/heterogeneous distribution with/without focal loss), and vessels (present/absent, lacy, peri-cryptal, irregular). The final testing consisted of reviewing BLI images/videos to determine whether the criteria accurately predicted the histology results. Confidence in adenoma identification (rated "1" to "5") and agreement in polyp (adenoma vs non-adenoma) identification and characterization per BASIC criteria were derived. Strength of interobserver agreement with kappa (k) value was reported for adenoma identification., Results: Ten endoscopy experts from the United States identified conventional adenoma (vs non-adenoma) with 94.4% accuracy, 95.0% sensitivity, 93.8% specificity, 93.8% positive predictive value, and 94.9% negative predictive value using BASIC criteria. Overall strength of interobserver agreement was high: kappa 0.89 (0.82-0.96). Agreement for the individual criteria was as follows: surface mucus (93.8%), regularity (65.6%), type of pit (40.6%), pit visibility (66.9%), pit distribution (57%), vessel visibility (73%), and being lacy (46%) and peri-cryptal (61%). The confidence in diagnosis was rated at high ≥4 in 67% of the cases., Conclusions: A group of US-based endoscopy experts have validated a simple and easily reproducible BLI classification system to characterize colorectal polyps with >90% accuracy and a high level of interobserver agreement., (© 2021 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)

Background and Aims: Endoscopic submucosal dissection (ESD) is becoming the preferred method for certain early GI malignancies; however, very few U.S. physicians have adopted this technique. This is in part because of the technically challenging nature of the procedure and the long learning curve. Several endoscopic robots are under development to address these complexities., Methods: This is a randomized, controlled, pilot study comparing conventional ESD versus robotic-assisted ESD (RESD) in an ex vivo bovine colon model. Five endoscopists without prior ESD or RESD experience were randomized into 2 groups (group 1, RESD after ESD; group 2, RESD before ESD). A standard template was used to create colonic lesions. The primary outcome was completeness of en bloc resection. Secondary outcomes included differences in procedure time, perforation rate, muscle injury rate, and National Aeronautical and Space Administration Task Load Index (NASA-TLX) to assess physical and mental workload., Results: Five endoscopists each performed 4 tissue resections (2 RESD and 2 ESD), for a total of 20 procedures. Complete en bloc resection was achieved in all RESD and in 50% of ESD (P < .0001). The perforation rate was higher in the ESD group (60% vs 30%, P = .18). Total procedure time (34.1 vs 88.6 min, P = .001) and dissection time (27.8 vs 79.4 minutes, P = .002) were lower for RESD. The NASA-TLX also revealed better results for RESD (28.4 vs 47.4, P = .01)., Conclusions: RESD appears to be more effective in obtaining en bloc resection with shorter procedure times and a lower perforation rate compared with conventional ESD as performed by ESD novices. RESD is also associated with lower physical and mental workloads., (Copyright © 2019 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Background: An education system for narrow band imaging (NBI) interpretation requires sufficient exposure to key features. However, access to didactic lectures by experienced teachers is limited in the United States., Aim: To develop and assess the effectiveness of a colorectal lesion identification tutorial., Methods: In the image analysis pretest, subjects including 9 experts and 8 trainees interpreted 50 white light (WL) and 50 NBI images of colorectal lesions. Results were not reviewed with subjects. Trainees then participated in an online tutorial emphasizing NBI interpretation in colorectal lesion analysis. A post-test was administered and diagnostic yields were compared to pre-education diagnostic yields., Results: Under the NBI mode, experts showed higher diagnostic yields (sensitivity 91.5% [87.3-94.4], specificity 90.6% [85.1-94.2], and accuracy 91.1% [88.5-93.7] with substantial interobserver agreement [κ value 0.71]) compared to trainees (sensitivity 89.6% [84.8-93.0], specificity 80.6% [73.5-86.3], and accuracy 86.0% [82.6-89.2], with substantial interobserver agreement [κ value 0.69]). The online tutorial improved the diagnostic yields of trainees to the equivalent level of experts (sensitivity 94.1% [90.0-96.6], specificity 89.0% [83.0-93.2], and accuracy 92.0% [89.3-94.7], p < 0.001 with substantial interobserver agreement [κ value 0.78])., Conclusions: This short, online tutorial improved diagnostic performance and interobserver agreement., (© 2018 S. Karger AG, Basel.)

Background: Narrowband imaging (NBI) allows characterization of colorectal polyps during endoscopy; however, this is underutilized by most US physicians. The aim of this study was to assess diagnostic performance of an NBI scoring system, based on the NBI international colorectal endoscopic classification, and determine a threshold score yielding the highest negative predictive value (NPV) in the characterization of colorectal neoplasia., Methods: During colonoscopy, colorectal lesions were scored using the NBI scoring system on a 0-3 scale for NBI findings. All lesions were biopsied or endoscopically removed for pathological examinations., Results: Two hundred and three patients were enrolled, and a total of 156 colorectal lesions were detected in 67 patients. Diagnostic yields under white light mode showed limited diagnostic performance [accuracy 75.6 % (68.9-82.3), sensitivity 69.2 % (58.6-78.3), specificity 84.6 % (73.1-92.0), positive predictive value (PPV) 86.3 % (75.8-92.9), NPV 66.3 % (55.0-76.0)]. Of NBI threshold scores from 1 to 3 for the diagnosis of neoplastic lesion, the score of ≥1 resulted in an accuracy of 88.5 % (83.5-93.5), sensitivity of 97.8 % (91.5-96.6), and specificity of 75.4 % (62.9-84.9), with PPV of 84.8 % (76.1-90.8) and NPV of 96.1 % (85.4-99.3)., Conclusions: The threshold value of ≥1 in this simplified NBI scoring system yielded the highest sensitivity and NPV for non-adenomatous colorectal polyps. This scoring system is simple to apply and is superior to white light endoscopy.

Background and Aim: We previously reported the effectiveness of color tone intensity analysis using autofluorescence imaging (AFI) for distinguishing between colorectal neoplastic and non-neoplastic lesions. Moreover, a second-generation AFI system has become commercially available in Japan. In the present study, we assessed the effectiveness of color tone intensity analysis using a second-generation AFI system for evaluating diminutive colorectal lesions., Methods: We retrospectively reviewed the cases of 35 consecutive patients with 101 diminutive colorectal lesions that were examined using a second-generation AFI system and resected at the Jikei University Hospital. We estimated the mean green-to-red (G/R) ratio - obtained by dividing the green color tone intensity by the red color tone intensity - of the lesions and compared the values of the neoplastic and non-neoplastic lesions. We also assessed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the AFI system for neoplastic lesion identification., Results: The mean G/R ratios of the non-neoplastic and neoplastic lesions were 1.06 and 0.87, respectively; the mean G/R ratio significantly differed between the neoplastic and non-neoplastic lesions. Using the second-generation AFI system, neoplastic lesions were identified with a sensitivity, specificity, PPV, and NPV of 94.2%, 91.8%, 92.5%, and 93.8%, respectively., Conclusion: Color intensity analysis of diminutive colorectal polyps using the second generation AFI system could effectively distinguish between neoplastic and non-neoplastic lesions., (© 2014 The Authors. Digestive Endoscopy © 2014 Japan Gastroenterological Endoscopy Society.)

Aim: To evaluate the efficacy of computer-assisted color analysis of colorectal lesions using a novel auto-fluorescence imaging (AFI) system to distinguish neoplastic lesions from non-neoplastic lesions and to predict the depth of invasion., Methods: From January 2013 to April 2013, consecutive patients with known polyps greater than 5 mm in size who were scheduled to undergo endoscopic treatment at The Jikei University Hospital were prospectively recruited for this study. All lesions were evaluated using a novel AFI system, and color-tone sampling was performed in a region of interest determined from narrow band imaging or from chromoendoscopy findings without magnification. The green/red (G/R) ratio for each lesion on the AFI images was calculated automatically using a computer-assisted color analysis system that permits real-time color analysis during endoscopic procedures., Results: A total of 88 patients with 163 lesions were enrolled in this study. There were significant differences in the G/R ratios of hyperplastic polyps (non-neoplastic lesions), adenoma/intramucosal cancer/submucosal (SM) superficial cancer, and SM deep cancer (P < 0.0001). The mean ± SD G/R ratios were 0.984 ± 0.118 in hyperplastic polyps and 0.827 ± 0.081 in neoplastic lesions. The G/R ratios of hyperplastic polyps were significantly higher than those of neoplastic lesions (P < 0.001). When a G/R ratio cut-off value of > 0.89 was applied to determine non-neoplastic lesions, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 83.9%, 82.6%, 53.1%, 95.6% and 82.8%, respectively. For neoplastic lesions, the mean G/R ratio was 0.834 ± 0.080 in adenoma/intramucosal cancer/SM superficial cancer and 0.746 ± 0.045 in SM deep cancer. The G/R ratio of adenoma/intramucosal cancer/SM superficial cancer was significantly higher than that of SM deep cancer (P < 0.01). When a G/R ratio cut-off value of < 0.77 was applied to distinguish SM deep cancers, the sensitivity, specificity, PPV, NPV, and accuracy were 80.0%, 84.4%, 29.6%, 98.1% and 84.1%, respectively., Conclusion: The novel AFI system with color analysis was effective in distinguishing non-neoplastic lesions from neoplastic lesions and might allow determination of the depth of invasion.

Objective: To clarify of the features of sessile serrated adenoma/polyp (SSA/P) observed with image-enhanced endoscopy using immunohistochemical staining., Materials and Methods: Twenty-five hyperplastic polyps (HP) and 46 SSA/P were studied with autofluorescence imaging (AFI) and magnifying endoscopy with narrow-band imaging (ME-NBI). AFI color change, capillary dilatation, existence of a mucous layer on the tumor surface, and pit dilatation under ME-NBI were examined retrospectively. Immunohistochemical staining was performed with the proliferation-associated antigen MIB-1 (Ki-67)., Results: Using AFI, a magenta color was observed in 32% of HP and 44% of SSA/P. With NBI observation, capillary dilatation was observed in 4% of HP and 11% of SSA/P, a mucous cap was observed in 60% of HP and 94% of SSA/P, and pit dilatation was observed in 28% of HP and 80% of SSA/P. When magenta color, capillary dilatation, mucous cap, and pit dilatation were used for the differential diagnosis of SSA/P from HP, the sensitivity, specificity, and accuracy were 43, 68, and 52% for AFI, respectively, 10, 96, and, 41% for capillary dilatation, respectively, 94, 40, and 75% for mucous cap, respectively, and 80, 72, and 78% for pit dilatation, respectively. Compared with HP, MIB-1-positive cells were more frequently distributed in the gland's intermediate zone in SSA/P., Conclusion: The biological malignant potential of SSA/P could be higher compared with HP as suggested by the MIB-1 stain. Therefore, endoscopic differentiation of SSA/P from HP is important, and the findings of a mucous cap and dilatated pit might be helpful for the differentiation of SSA/P from HP.

Introduction: Narrow-band imaging (NBI), an emerging imaging technology, allows direct visualization of capillaries on the gastrointestinal mucosal surface. The combination of NBI and magnifying endoscopy can be used to identify morphological changes in these capillaries during the process of carcinogenesis., Findings and Conclusions: Thus far, pathological predictions based on capillary pattern classifications have been reported to have good diagnostic accuracy. However, most of these studies have been single-center trials based on each institutional classification, and worldwide multicenter trials aimed at their standardization are needed to validate the clinical benefits of the various NBI classification systems.

Background: This pilot study sought to investigate the performance and safety of a reduced-volume oral sulfate solution for use as a bowel-cleansing regimen prior to colonoscopy in a Japanese population., Methods: Subjects followed a prescribed split-dose regimen in which the first portion was taken on the evening before colonoscopy and the second portion on the morning of the procedure. To determine the performance of this regimen, the quality of colon cleansing was assessed in each case using a validated four-point scale, and elapsed time to complete the preparation was recorded. Side effects and adverse events were investigated by blood sampling and questionnaire., Results: The successful preparation rate based on the colon-cleansing score was 97 % (30/31). Mean elapsed time to complete the preparation on the day of colonoscopy was 71 min. Serum levels of indirect bilirubin were significantly increased to abnormal levels following the preparation, although these changes were only transient. Preparation-related symptoms of nausea and vomiting were presented in only one case., Conclusions: This pilot study showed the oral sulfate solution-based bowel preparation to be safe, easy, and quick to use for Japanese patients. A larger study is necessary to statistically verify these results.

Introduction: This study examined whether magnifying endoscopy with narrow-band Imaging observation could be useful selecting the appropriate treatment for early colon cancer., Patients and Methods: We analyzed 551 cases of colon tumors excised endoscopically or surgically, comprising 68 with large hyperplastic polyps, 25 traditional serrated adenomas, 141 tubular adenomas, 177 intramucosal cancers and 140 submucosal invasive (SM) cancers. We classified capillary network pattern into four types according to the degree of dilatation, irregularity and distribution of microcapillary features. These results were then compared with the histological findings., Results: The comparison of capillary pattern and histological features showed microcapillary networks by magnifying endoscopy with narrow-band imaging observation in intramucosal lesion or SM cancer with remnant neoplastic glands at the superficial layer., Conclusions: The remaining microcapillary network was designed to maintain the architecture of neoplastic glands, even in the presence of subumucosal invasion. Consequently, loss of this network could correlate with depth of tumor invasion and histological reaction. Therefore, even if the tumor, remained of network was diagnosed to invade into SM layer, it should be checked up further examination by using magnifying endoscopy with crystal violet staining., (© 2011 The Authors. Digestive Endoscopy © 2011 Japan Gastroenterological Endoscopy Society.)

Purpose: The aim of this pilot study was to compare the performance and safety of the newly developed sodium phosphate (NaP) tablet (with and without laxatives) and polyethylene glycol (PEG), as bowel-cleansing regimens prior to colonoscopy., Methods: A total of 35 patients were randomized to one of the following three groups: NaP + laxative, NaP, or PEG. Quality of colon cleansing was assessed using a validated four-point scale, and the primary outcome measures were the mean overall colon cleansing and microcrystalline cellu1ose (MCC)-remaining scores in each group., Results: The mean elapsed time for bowel cleansing in the NaP + laxative group (167.72 +/- 21.37 min) was significantly less than in the NaP group (218.00 +/- 20.58 min) and the PEG group (202.00 +/- 27.91 min; n = 11, 10, and 10 respectively; P < 0.05). The NaP + laxative group showed a superior overall colon-cleansing score compared to both the NaP and PEG groups and similarly, the overall colon MCC-remaining score in the NaP + laxative group was superior to the NaP group. Serum levels of inorganic phosphorus were significantly increased to abnormal levels in the NaP + laxative and NaP groups, but these increases were only transient., Conclusions: This pilot study shows that NaP-based bowel preparations are easy, quick, and safe to use. Colonoscopic visualization is decreased by MCC when NaP is used alone but is improved by the addition of laxatives on the previous day. A larger study is necessary to statistically verify these results.

Background: Autofluorescence endoscopy (AFE) may improve detection and diagnosis of colorectal lesions. Recently, AFE based on a high-resolution video endoscope was developed., Objective: A novel high-resolution video AFE system was used to quantify autofluorescence of colorectal lesions to determine the characteristics of non-neoplastic and neoplastic lesions., Design: Retrospective observational study., Setting: Single-center referral hospital., Patients: Ninety-seven patients with 103 colorectal lesions (22 non-neoplastic and 81 neoplastic lesions) who underwent AFE and were treated by using endoscopy or by surgery., Intervention: Recorded digital AFE images were analyzed to quantify autofluorescence. The following autofluorescence indexes were calculated: the green/red (G/R) ratio for each lesion, the color-contrast index between each lesion, and the corresponding normal region., Main Outcome Measurements: The G:R ratio, color-contrast index, and histopathologic characteristics for each colorectal lesion., Results: The mean G/R ratio was significantly higher in non-neoplastic lesions (1.17 [95% CI, 1.10-1.24], n = 22) than in neoplastic lesions (0.65 [95% CI, 0.63-0.68], n = 81) (P < .001). Mean color-contrast indexes were significantly lower in non-neoplastic lesions (7.99 [95% CI, 6.40-9.58], n = 22) than neoplastic lesions (35.06 [95% CI, 32.79-37.33], n = 81; P < .001). With a cutoff value of 1.01 for the G/R ratio and 13.94 for color-contrast index, AFE had a sensitivity and specificity of 98.8% and 86.4% respectively, for G/R ratio, and 98.8% and 90.9%, respectively, for color contrast index, in differentiating neoplastic from non-neoplastic colorectal lesions., Limitations: Retrospective design., Conclusions: The quantification of digital AFE images obtained from the novel high-resolution videoendoscopy system revealed that autofluorescence was significantly different between non-neoplastic and neoplastic lesions, and color tone in AFE may represent the histopathologic characteristics of the lesion.

Colonoscopies allow surgeons to detect common diseases, that is, colorectal cancer, ulcers, and other ailments. However, there is a risk of bleeding in the lower gastrointestinal (GI) tract while maneuvering endoscopes. This may be due to perforations, hemorrhaging, polyps, diverticula, or post‐biopsy complications. Thus, it is essential for the surgeon to be able to detect bleeding at the site and evaluate the severity of blood leakage. Herein, a soft sensor that can detect the presence of blood at the bleeding site during colonoscopies is presented. The sensor consists of optical waveguides that interface with a microfluidic channel. Blood flow causes absorption and scattering of incident light that can be picked up by the optical sensing apparatus via light transmission through the waveguide. The surgeon can be alerted when bleeding occurs through a graphical user interface. The device is compact and measures only 1 mm thick. This allows the sensor to be circumferentially mounted onto a colonoscope at different locations. The sensor is able to record the presence of blood as an optical loss, rapidly detect the presence of blood under 100 ms as it enters the microchannel, and differentiate between gastric fluid and blood through changes in measured optical loss. [ABSTRACT FROM AUTHOR]