Kudo Pit Pattern Research Articles

Dysplasia detection rates under a surveillance program in a tertiary referral center for inflammatory bowel diseases: Real-world data

Background and aimsSurveillance colonoscopies are crucial for high-risk patients with inflammatory bowel diseases (IBD) to detect colorectal carcinoma (CRC). However, there is no established quality metric for dysplasia detection rate (DDR) in IBD surveillance. This study assessed the DDR in a dedicated surveillance program at a tertiary referral center for IBD. MethodsConsecutive patients with quiescent colitis were enrolled in a cross-sectional study evaluating DDR. High-definition colonoscopy with dye chromoendoscopy (DCE) was performed by a specialized operator. Advanced dysplasia (AD) was defined as low-grade dysplasia ≥ 10 mm, high-grade dysplasia, or colorectal cancer. Risk factors for dysplasia detection were analyzed. ResultsIn total, 119 patients underwent 151 procedures, identifying 206 lesions, of which 40 dysplastic with seven AD . Per-lesion and per-procedure DDR were 19.4 % and 20.5 %, respectively. The per-procedure AD detection rate (ADDR) was 4.6 %. A Kudo pit pattern of II-V had a sensitivity of 92.5 % for dysplasia detection but a false positive rate of 64.8 % (p < 0.001). Age at diagnosis and at index colonoscopy and past or indefinite dysplasia were associated with per-procedure dysplasia detection. ConclusionsIn a real-world setting, a dedicated surveillance program achieved a high DDR. We suggest that optimal DDR in high-risk IBD patients be defined and implemented as a standardized quality measure for surveillance programs.

Serrated polyps

Colorectal lesions (CRLs) <10 mm found at colonoscopy tend towards "diagnose-and-leave" or "resect-and-discard" strategies based on real-time Kudo glandular pit-pattern's assessment using i-Scan. However, i-Scan has not yet been validated for Kudo's classification. We aimed to assess whether, in routine colonoscopy, i-Scan without magnification and optical enhancement (M-OE) reliably differentiates hyperplastic polyps (HPs) from other serrated lesions (SLs) and conventional adenomas (CAs), and, among SLs, HPs from sessile serrated lesions (SSLs) and traditional or unknown serrated adenomas (TSAs, USAs), in Kudo type II CRLs<10 mm, according to ASGE Preservation and Incorporation of Valuable endoscopic Innovations (PIVI) recommended negative predictive value (NPV) threshold for adenomas. Prospectively recorded CRLs over 12 months, classified according to Kudo pit-pattern using i-Scan, were retrospectively compared with histology. Overall, 898 ≤5-mm and 704 6- to 9-mm CRLs were included. Type II pit-pattern was found in 76.6% and 38.7% of HPs and SSLs-TSAs/CAs (P<0.000001), and in 84.1% and 26.6% of SLs and CAs (P<0.000001). Among SLs, it was found in 81.9% and 86.6% of HPs and SSLs-TSAs. In CRLs≤5 mm, HPs were prevalent over other SLs (P=0.00001); in CRLs 6-9 mm, CAs were prevalent (P<0.000001). About 77% of SLs in right colon were SSLs-TSAs; 82% in left colon were HPs. PIVI ≥90% NPV threshold for adenomas was reached for CRLs 6-9mm (92.1%), nearly achieved for CRLs≤5 mm (88.2%), and not reached for SLs independently on the size. A strategy of "diagnose-and-leave" or "resect-and-discard" cannot be recommended for SLs<10 mm with Kudo type II pit-pattern using i-Scan, especially in right colon, if M-OE unavailable.

P164 Dysplasia detection rates in a surveillance program real-world data from a tertiary referral center for inflammatory bowel diseases

Abstract Background Patients with inflammatory bowel diseases (IBD) with an increased risk of developing colorectal carcinoma should undergo periodic surveillance colonoscopies. There is no quality metric for dysplasia detection rate (DDR) in IBD surveillance. We evaluated DDR in a dedicated surveillance program at a tertiary IBD referral center. Methods This cross-sectional study assessed DDR among consecutive patients with quiescent colitis enrolled in our surveillance program. Patients underwent high-definition colonoscopy with dye chromoendoscopy (DCE). A single specialized operator performed the procedures. Advanced dysplasia (AD) was defined as low-grade dysplasia ≥ 10mm, high-grade dysplasia, or colorectal cancer. We evaluated risk factors for dysplasia detection. Results Overall, 119 patients [female: 39.5%; median age: 54 years (IQR 43-66); median disease duration: 20 years (IQR 14-29)] underwent 151 procedures that revealed 206 lesions, of which 40 were dysplastic, and seven were considered AD. Per-procedure and per-lesion DDR were: 20.5%, and 19.4%, respectively. Per-procedure AD detection rate (ADDR) was 4.6%. Per-procedure dysplasia detection was associated with increased age at diagnosis at the index colonoscopy and past dysplasia or indefinite dysplasia, however, on multivariable analysis, only past dysplasia or indefinite dysplasia maintained a significant association (AdjOR 4.84, 95% CI 1.52-15.45, p=0.008). A Kudo pit pattern of II-V had a sensitivity of 92.5% for per-lesion dysplasia detection but a false positive rate of 64.8% (p&amp;lt;0.001). Conclusion DDR in a dedicated surveillance program in a real-world setting reached 20%. DDR should be considered a quality measure while surveying high-risk patients with IBD.

Do surface morphology and pit pattern have a role in predicting cancer for colon polyps in North America?

The surface morphology of colorectal polyps is well correlated with submucosal invasion in Eastern Countries but not in North America. We aimed to investigate associations between the Paris classification, surface morphology, and Kudo pit pattern to submucosal invasion in advanced endoscopic resection techniques. We retrospectively analyzed prospectively collected data of consecutive advanced endoscopic procedures conducted by a single surgeon between August 2017 and October 2018. The data included patients' demographics, the endoscopic finding of polyps (Paris, Kudo, and surface morphology), and pathology results. The study consisted of 138 lesions, and the mean age was 67 ± 10years. The most common polyp locations were cecum (n = 41, 30%) followed by ascending colon (n = 28, 20%), and sigmoid colon (n = 18, 13%).The median polyp size was 30mm (25-40). The en-bloc resection rate was 96%, and 11 (8%) polyps had adenocarcinoma with submucosal invasion. Nine patients (6.5%) had late bleeding, and 3 (2.2%) perforation occurred. Polyps with pit pattern of Kudo IV (n = 4, 36.4%) and Kudo V (n = 6, 54.5%) were associated with submucosal invasion. Surface morphology and pit pattern can predict submucosal invasion in the North American patient population. Polyp morphology may aid polyp selection for advanced endoscopic interventions.

Endoscopic Predictors of Neoplastic Lesions in Inflammatory Bowel Diseases Patients Undergoing Chromoendoscopy.

Simple SummaryPatients with long-standing and extensive/left-sided colonic inflammatory bowel diseases (IBD) have enhanced risk of developing colorectal cancer with respect to the general population. Dye-based chromoendoscopy (DCE) is now considered as the best surveillance strategy to prevent colon cancer in such patients, even though the endoscopic features of the DCE-evidenced lesions that predict neoplasia are not fully clarified. This study was aimed at identifying predictive factors of dysplastic/neoplastic lesions in IBD patients undergoing DCE. Our study shows that polypoid lesions with specific morphologic features and size greater than 7 mm are frequently dysplastic/neoplastic and, therefore, must be removed.Dye-based chromoendoscopy (DCE) with targeted biopsies is recommended for surveillance of patients with long-standing inflammatory bowel diseases (IBD), but endoscopic features that predict dysplasia are not fully clarified. We here aimed at identifying predictive factors of dysplastic/neoplastic lesions in IBD patients undergoing DCE. Two-hundred-and-nineteen patients were consecutively and prospectively enrolled from October 2019 to March 2022. One-hundred-and-forty-five out of 219 patients underwent DCE, and 148 lesions were detected in 79/145 (54%) patients. Thirty-nine lesions (26%) were dysplastic and one of them contained a CRC. Among these lesions, 7 (17.9%) had Kudo pit pattern I-II and 32 (82.1%) had a neoplastic pit pattern (Kudo III-IV). Multivariate analysis showed that neoplastic lesions Kudo III-IV (OR: 5.8, 95% CI: 2.3–14.6; p = 0.0002), lesion’s size (OR 1.16, 95% CI: 1.06–1.26; p = 0.0009), and polypoid lesions according to Paris Classification (OR 7.4, 95% CI: 2.7–20.2; p = 0.0001) were independent predictors of dysplasia. A cut-off of lesion’s size > 7 mm was identified as the best predictor of dysplasia. Among such features, Kudo pit pattern III-IV had the highest sensitivity and specificity to predict dysplasia (79% and 80%, respectively). Lesions with all three endoscopic features had a sensitivity of 90% and specificity of 100% to predict dysplasia. In contrast, non-polypoid lesions were inversely associated with dysplasia (OR 0.13, 95% CI: 0.05–0.36; p = 0.0001). These findings indicate that, in IBD patients, DCE-evidenced polypoid lesions with Kudo pit pattern III-IV and size > 7 mm are frequently dysplastic.

Magnifying Chromoendoscopy with Flexible Spectral Imaging Color Enhancement, Indigo Carmine, and Crystal Violet in Predicting the Histopathology of Colorectal Polyps: Diagnostic Value in a Scare-Setting Resource.

Background and Aims Virtual magnifying chromoendoscopy with flexible spectral imaging color enhancement (FICE), image-enhanced endoscopy techniques, and dye-staining magnifying chromoendoscopy (with Indigo carmine and Crystal violet) have contributed to better visualization of the pit pattern and vascular structure of colorectal polyp. Therefore, magnifying chromoendoscopy is capable of predicting the histopathological results of colorectal polyp without biopsy and remains their diagnostic values over time, especially in scare-setting resources. This study compared the images of magnifying chromoendoscopy between FICE, Indigo carmine, and Crystal violet and then assessed their diagnostic values based on colorectal polyps' histopathology as a gold standard. Methods A total of 332 polyps of 266 patients were endoscopically evaluated from June 2016 to September 2019. After identified by white light endoscopy, polyps continued to be evaluated by virtual magnifying chromoendoscopy (×50-150 times) with FICE. The capillary-vessel pattern was divided into 5 subtypes according to the number, morphology, and distribution of the fine blood vessels according to Teixeira classification. Next, they were stained with Indigo carmine 0.2% and then Crystal violet 0.05% and were classified according to Kudo's pit pattern classification. Finally, polyps were resected by endoscopy or surgery and biopsy and compared with histopathological results of either neoplastic or nonplastic polyp. Results The number of neoplastic polyps was 278/332 with 231 adenoma polyps and 47 carcinoma polyps. Magnifying chromoendoscopy has high sensitivity and accuracy when compared with the histopathological results of colorectal polyps. The sensitivity, specificity, and accuracy of magnifying chromoendoscopy with Crystal violet are 97.2%, 72.2%, and 93.0%; with Indigo carmine are 96.0%, 72.2%, and 92.1%; and with FICE are 92.1%, 68.5%, and 88.3%.Conclusions Among the three methods, Crystal violet has the highest sensitivity and accuracy in predicting histopathological results of colorectal polyps. FICE has shown its diagnostic value with reliable sensitivity and accuracy and should still be a reasonable endoscopic choice for physicians in scare-setting resources regardless its moderate specificity. Physicians should base on their facility and capability to determine an appropriate endoscopy technique.

A Rectum-Specific Selective Resection Algorithm Optimizes Oncologic Outcomes for Large Nonpedunculated Rectal Polyps

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are complementary techniques for large (≥20 mm) nonpedunculated rectal polyps (LNPRPs). A mechanism for appropriate technique selection has not been described. We evaluated the performance of a selective resection algorithm (SRA) (August 2017 to April 2021) compared with a universal EMR algorithm (UEA) (July 2008 to July 2017) for LNPRPs within a prospective observational study. In the SRA, LNPRPs with features of superficial submucosal invasive cancer (SMIC) (<1000 μm; Kudo pit pattern Vi), or with an increased risk of SMIC (Paris 0-Is or 0-IIa+Is nongranular, 0-IIa+Is granular with a dominant nodule ≥10 mm) underwent ESD. The remaining LNPRPs underwent EMR. Algorithm performance was evaluated by SMIC identified after EMR, curative oncologic resection (R0 resection, superficial SMIC, absence of negative histologic features), technical success, adverse events, and recurrence at first surveillance colonoscopy. A total of 480 LNPRPs were evaluated (290 UEA, 190 SRA). Median lesion size was 40 (interquartile range, 30-60) mm. SMIC was identified in 56 (11.7%) LNPRPs. Significant differences in SMIC after EMR (SRA 1 [1.0%] vs UEA 35 [12.1%]; P= .001) and curative oncologic resection (SRA n= 7 [33.3%] vs UEA n= 2 [5.7%]; P= .010) were identified. No significant differences in technical success or adverse events were identified (all P > .137). Among LNPRPs with SMIC amenable to curative oncologic resection and which underwent ESD, 100% (n= 7 of 7) were cured. A rectum-specific SRA optimizes oncologic outcomes for LNPRPs and mitigates the risk of piecemeal resection of cancers.

Kudo's pit pattern classification for in vivo optical diagnosis and discrimination of advanced colorectal polyps.

Colonoscopy is currently the basic diagnostic tool for the large intestine. The size of lesions assessed during the investigation is one criterion for assessing the risk of polyps transforming into colorectal cancer. The techno-logical development of endoscopes and the possibility of direct assessment of lesion's surface during the endoscopic examination and to use appropriate treatment. The aim of this study is to analyze the consistency between the histopathological assessment of high-risk lesions in colonoscopy and the determination according to Kudo's pit pattern classification. The analysis included the results of colonoscopies performed over a 2-year period, in which polyps were diagnosed endoscopically and either polypectomies were performed, or sections were taken from these polyps and a pit pattern analysis was done according to Kudo's classification. A total of 1038 patients (age, 67.2 ± 12.7 years) were enrolled in the study. Of the 1981 samples taken in total, polyps larger than 1 cm were found in 96 cases, laterally spreading tumors (LSTs) were found in 48 cases, and macroscopic infiltration or tumors were found in 110 cases. The results of the histopathological examination were obtained in 248 cases. A value of 4 or higher in the Kudo classification turned out to be the best parameter to differentiate malignant lesions from benign ones for lesions larger than 1 cm and laterally spreading tumors, with a sensitivity of 91.2% and a specificity of 70.4%. The assessment of polyps according to Kudo's classification is a useful tool for assessing the malignancy of lesions as part of a routine colonoscopy.

A126 ONCE IS BY CHANCE, TWO IS A TREND: A RECURRING FINDING WITHIN THE POST-RESECTION DEFECT

Abstract Background A 74-year-old male was referred for the management of a large non-pedunculated colorectal polyp in the transverse colon. On optical evaluation, including high-definition white-light and narrow-band imaging (NBI), a 30mm 0-IIA non-granular large non-pedunculated colorectal polyps (LNPCP) was identified with optical features in keeping with adenomatous histopathology (NBI International Colorectal Endoscopic II, Japan NBI Expert Team IIA, Kudo Pit Pattern III/IV). Endoscopic mucosal resection (EMR) was performed. During sequential tissue transection and evaluation of the expanding submucosal defect a hole with a surrounding white-cautery ring was identified in keeping with significant deep mural injury. However, on careful evaluation a cystic structure was identified with a viscous amorphous substance emanating from it. Endoscopic resection of the lesion was completed with subsequent through-the-scope mechanical clip closure of the area of concern. Aims case report showing unique finding of intra-cellular mucin emanating from the post-resection defect has been identified as a potential intra-procedural finding of a mucinous adenocarcinoma Methods Endoscopic mucosal resection of a mid transverse colon polyp Results Histopathology identified a villous adenoma with high-grade dysplasia with submucosal mucin and an indeterminate focus of carcinoma; highly suspicious for a mucinous adenocarcinoma. No muscularis propria was identified. After multi-disciplinary review, the patient underwent laparoscopic right hemicolectomy with no evidence of invasive disease. Conclusions Recently coined as the “fish-eye” polypectomy defect, intra-cellular mucin emanating from the post-resection defect has been identified as a potential intra-procedural finding of a mucinous adenocarcinoma; specifically, in an otherwise benign appearing LNPCP based on real-time optical evaluation. Herein we describe the second case in the literature. This reinforces the importance of meticulous evaluation of the post-resection defect to stratify this finding from deep mural injury. Moreover, further understanding of the clinical ramifications of this unique intra-procedural finding is needed. Funding Agencies None

A111 A RECTUM-SPECIFIC SELECTIVE RESECTION ALGORITHM OPTIMIZES ONCOLOGIC OUTCOMES FOR LARGE NON-PEDUNCULATED RECTAL POLYPS

BackgroundEndoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are complementary techniques for large (≥ 20mm) non-pedunculated rectal polyps (LNPRPs). A mechanism for appropriate technique selection has not been described.AimsTo evaluate whether a selective resection algorithm using EMR and ESD, based on real-time optical evaluation, optimizes oncologic outcomes for LNPRPsMethodsWe evaluated the performance of a selective resection algorithm (SRA; 08/2017-04/2021) compared to a universal EMR algorithm (UEA; 07/2008-07/2017) for LNPRPs within a prospective observational study. In the SRA, LNPRPs with features of superficial submucosal invasive cancer (SMIC < 1000μm; S-SMIC; Kudo pit pattern Vi), or with an increased risk of SMIC (Paris 0-Is or 0-IIa+Is non-granular, 0-IIa+Is granular with a dominant nodule ≥ 10mm) underwent ESD. The remaining LNPRPs underwent EMR. Algorithm performance was evaluated by SMIC identified after EMR, curative oncologic resection (R0 resection, S-SMIC, absence of negative histologic features), technical success, adverse events, and recurrence at first surveillance colonoscopy.Results480 LNPRPs were evaluated (290 UEA, 190 SRA). Median lesion size was 40mm (IQR 30-60mm). In the SRA, 103 (54.2%) and 87 (45.8%) LNPRPs underwent EMR and ESD, respectively. SMIC was identified in 56 (11.7%) LNPRPs. Significant differences in SMIC after EMR (SRA 1 (1.0%) vs. UEA 35 (12.1%); p = 0.001), curative oncologic resection (SRA 7 (33.3%) vs. UEA 2 (5.7%); p = 0.010), and recurrence (SRA 2 (1.6%) vs. UEA 40 (17.2%); p < 0.001) were identified. No significant differences in technical success or adverse events were identified (all p > 0.137). Among potentially curable malignant LNPRPs which underwent ESD, 100% (7/7) were cured.ConclusionsA SRA optimizes oncologic outcomes for LNPRPs and mitigates the risk of piecemeal resection of cancers.Oncologic Outcomes for Malignant LNPRPsOverall LNPRPs (N = 56, %)UEA LNPRPs (N = 35, %)SRA LNPRPs (N = 21, %)P-valueSMIC after EMR*36 (9.2)35 (12.1)1 (1.0)0.001En Bloc Resection23 (41.1)4 (11.4)19 (90.5)<0.001R0 Resection20 (35.7)2 (5.7)18 (85.7)<0.001Curative Resection9 (16.1)2 (5.7)7 (33.3)0.010EMR, endoscopic mucosal resection; LNPRP, large non-pedunculated rectal polyp; SMIC, submucosal invasive cancer; SRA, selective resection algorithm; UEA, universal endoscopic mucosal resection algorithm *Denominator: Large non-pedunculated rectal polyps which underwent endoscopic mucosal resectionFunding AgenciesThe Cancer Institute of New South Wales provided funding for a research nurse and data manager to assist with the administration of the study. Neal Shahidi was supported by the University of British Columbia Clinician Investigator Program. There was no influence from either institution regarding study design or conduct, data collection, management, analysis, interpretation, preparation, review, or approval of the manuscript.

Three-dimensional morphological characterization of colorectal pits from label-free microscopy images.

The prognosis of colorectal cancer (CRC), one of the most prevalent pathologies worldwide, is linked to early detection. Kudo's pit pattern classification states morphological pit patterns of the Lieberkühn crypts by analyzing the superficial mucosa, predicting the histology of colorectal lesions. Its use as a highly accurate two-dimensional diagnostic criterion has increased, mostly involving expert endoscopists' judgment. The processing of autofluorescence images could allow the diagnostic, bypassing staining techniques and decreasing the biopsies, resources and times involved in the inspection. That criterion could be extended by data of the pit three-dimensional (3D) morphology. Thus, this work was aimed at obtaining 3D morphological information by quantifying geometrical and shape descriptors through software processing and analysis of widefield autofluorescence microscopy image stacks acquired by fresh colon tissue samples from a murine model of CRC. Statistical analyses included pits from control mice and from the second (2nd), fourth (4th), and eighth (8th) weeks of treatment. Statistically significant differences were found for almost all parameters between the pits from control and from the 4th treated week, stating that the major morphological changes begin after the 2nd week. In particular, pits from control or initial treatment time points were more tubular, straighter and less rough than the ones from later treatment points. Therefore, they may be more associated to normal or non-neoplastic crypt lumens than linked to adenomas or even cancer crypts. These preliminary outcomes could be considered an advance in 3D pit morphology characterization.

S1711 Ischemic Colitis Combined With Adenomatous Polyp Presenting as Malignant-Like Lesion

Introduction: Ischemic colitis is a common colonic vascular diordedr in the elderly population, so is adenomatous polyps in the colon. We present an unusal case where a patient had an ischemic colitis in the area of an adenomatous polyp, giving an appearance that resembles malignant neoplasm of the colon. Case Description/Methods: An 83-year-old female presented to the emergency department with flash pulmonary edema secondary to hypertensive emergency requiring urgent hemodialysis. She had no history of atrial fibrillation that would suggest thromboembolic phenomenon. She reported no GI bleeding history and never underwent an endoscopy or colonoscopy. Laboratory studies showed up trending troponin (from 0.1 to 2.5) with EKG changes concerning for non-ST elevation myocardial infarction (NSTEMI). Pt was started on treatment with dual anti platelet therapy and heparin infusion. Next morning, the patient reported a sudden urge to defecate and crampy abdominal pain which resolved after large maroon-colored bowel movement. Significant drop in Hb from 9.2 to 7.1 ( >2 grams/dl) was found but the patient remained hemodynamically stable. Colonoscopy was performed which showed a 4-5 cm ulcerated raised lesion with round semi-pedunculated polyp at the edge of the lesion (Kudo Pit pattern 3 L) in the descending colon [Figure]. Biopsies were obtained from the ulcerated lesion as well as the polyp located at the edge of the lesion. Pathologic examination of ulcer lesion biopsy showed necrotic debris and inflammatory exudates with reactive/reparative epithelial changes along with minute fragments showing crypt drop out and hyalinized lamina propria, suggestive of ischemic change. Deeper levels were examined and showed no malignancy. Biopsy of polyp showed fragments of tubular adenoma. Patient recovered from her ischemic colitis and NSTEMI and recovered well and was discharged from the hospital. Discussion: The incidental proximity of the ischemic area to the polyp gave a malignant appearance to the area. However, biopsies confirmed there was only ischemic changes in the ulcerated area and biopsies from the polyp showed tubular adenoma with no malignant cells nor high grade dysplasia. The ischemic colitis is likely the cause of bleeding in this case. She was scheduled for follow-up for discussion of repeat colonoscopy for polyp resection on elective basis.Figure 1.: Ulcerated raised lesion with round semi-pedunculated polyp at the edge of the lesion in the descending colon.

Value of Magnifying Chromoendoscopy and Magnifying Optical Enhancement Technology in Classifying Colorectal Polyps: A Prospective Controlled Study.

Background and Aims Magnifying chromoendoscopy (ME-CE) through the observation of pit patterns is a productive way to distinguish between neoplastic and nonneoplastic polyps. Magnifying optical enhancement technology (ME-OE) is an emerging virtual chromoendoscopy imaging technology and appeared to be a promising approach. However, this information is currently not available. This study is aimed at comparing the differential diagnostic value of ME-CE and OE for neoplastic and nonneoplastic polyps. Patients and Methods. Consecutive patients undergoing colonoscopy were randomized (1 : 1) into examination by ME-OE or ME-CE. Histopathological findings were utilized as the reference standard. Accuracy, sensitivity, specificity, and positive and negative predictive values of two endoscopy methods were compared using ME-OE (were classified according to the JNET classification) and ME-CE (were classified according to the Kudo pit pattern classification), respectively, and the time to predict the histological polyp type was compared. And the agreements between the pathological and clinical diagnosis by ME-OE or ME-CE were analyzed. Results A total of 365 polyps were found in the 220 patients included (ME-OE: 185; ME-CE: 180.202 had nonneoplastic polyps, 163 had neoplastic polyps). The diagnostic accuracy of ME-OE was higher than that of ME-CE (93% vs. 92%, p > 0.05). The average diagnosis time was lower in ME-OE than ME-CE (83 ± 26.4 s vs. 194 ± 17.7 s, p < 0.001). The agreements between the pathological and clinical diagnosis were at least substantial in both groups. Conclusion ME-OE was superlative to ME-CE in predicting the histology of polyps. OE devoted classification would possibly similarly enhance the endoscopist performance. The trial is registered with ChiCT2000032075.

Virtual chromoendoscopy with iSCAN as an alternative method to dye-spray chromoendoscopy for dysplasia detection in long-standing colonic inflammatory bowel disease: a case–control study

Objective Patients with long-standing colonic inflammatory bowel disease (cIBD) are at increased risk of developing colorectal cancer (CRC). Dye-spray chromoendoscopy (DCE) with targeted biopsies is the preferred technique for surveillance of dysplasia. Virtual chromoendoscopy (VCE) are arising to improve detection rates and adherence to surveillance guidelines, although its role is not yet well defined. The purpose of this study is to assess the effectiveness of VCE with iSCAN as an alternative method for dysplasia detection in cIBD. Methods Retrospective case–control study with 191 patients included, 98 in the DCE (Indigo carmine) group and 93 in the VCE (iSCAN, twin-mode 1–3) group. The dysplasia detection and the exploration time were analysed. A logistic regression analysis was performed to ascertain the factors related to colonic dysplasia. Results A total of 44 dysplastic lesions were detected in 21 (11%) patients. No differences were found in the per lesion and the per patient analysis (dysplastic versus non-dysplastic). Median withdrawal time was shorter in the VCE group than in the DCE group (9 min versus 14 min; p < .001). Location of lesions in the right colon was independently associated with an increased risk for colonic dysplasia (OR = 4.04, 95%CI 1.11–14.65; p = .034) after adjusting for age at inclusion, age at diagnosis, high risk for CRC and Kudo pit pattern. Conclusions VCE with iSCAN presents a similar diagnostic performance to conventional DCE in the detection of colonic dysplasia in patients with long-standing cIBD. Furthermore, VCE with iSCAN is a less time-consuming surveillance alternative to DCE.

How to Manage the Large Nonpedunculated Colorectal Polyp

How to Manage the Large Nonpedunculated Colorectal Polyp

Endoscopic Recognition and Management Strategies for Malignant Colorectal Polyps: Recommendations of the US Multi-Society Task Force on Colorectal Cancer.

Endoscopic Recognition and Management Strategies for Malignant Colorectal Polyps: Recommendations of the US Multi-Society Task Force on Colorectal Cancer.

S3373 Endoscopic Mucosal Resection of a Lateral Spreading Tumors Descending Colon

INTRODUCTION: Lateral spreading tumors (LST) are nonpolypoid lesions larger than 10 mm in width that extend laterally and circumferentially rather than vertically. These lesions have the potential for malignant transformation. Therefore, complete resection is recommended. However, given the fact that these lesions most of the time are flat in morphology and have large dimensions, complete resection using simple methods such as snare polypectomy is challenging. Endoscopic Mucosal Resection (EMR) and endoscopic mucosal dissection (ESD) are minimally invasive resection techniques that can be used to resect LST completely. Nonetheless, careful examination and evaluation of LST using high-quality images such as narrowband imaging (NBI) and Chromoendoscopy are important before performing EMR or ESD. Here, we present a case of large LST that was nicely demarcated using Chromoendoscopy. CASE DESCRIPTION/METHODS: A 71-year-old Caucasian male with multiple comorbidities who initially presented for colon cancer screening. LST greater than 2 cm in size and involving multiple folds was found. The lesion was encompassing >50% of mucosal surface of the descending colon. The polyp was carefully examined with narrowband imaging (NBI) and Chromoendoscopy (indigo carmine was sprayed on top of the lesion and subsequently crystal violet). The lesion met Paris classification 0–2A and Kudo pit pattern 3L. ORISE gel was injected to create a submucosal pillow at the base of this polyp and the polyp lifted well. The polyp was then completely resected via EMR. A small residual defect was seen but no closure was required. Histopathology report showed hyperplastic polyp. A follow-up colonoscopy was performed few months later. The resection site was notable for significant scarring and narrowing of the colonic lumen. The mucosa appeared pale with slightly larger pits, and irregular sparse vessels. However, there was no evidence of recurrent adenoma at the resection site upon evaluation by NBI and Chromoendoscpy. Biopsies were taken from the base of the resection site. Final histopathology report from the resection site showed tubular adenoma with low grade dysplasia. DISCUSSION: Careful examination and evaluation of LST by using chromoendoscopy and NBI are crucial before performing EMR or ESD safely and effectively.

Colon mucosal neoplasia referred for endoscopic mucosal resection: Recurrence of adenomas and prediction of submucosal invasion

BACKGROUNDEndoscopic mucosal resection (EMR) is an effective and minimally invasive alternative to surgery for large polyps and laterally spreading lesions. Gross morphology and surface characteristics may help predict submucosal invasion of the lesion (SMIL) during endoscopic evaluation. This is one of the largest single-center studies reporting endoscopic mucosal resection for larger (≥ 20 mm) colorectal lesions in the United States.AIMTo determine the recurrence rate of adenomas and endoscopic features that may predict submucosal invasion of colonic mucosal neoplasia.METHODSThis is a retrospective cohort study of all the patients referred for endoscopic mucosal resection for lesions ≥ 20 mm, spanning a period from January 2013 to February 2017. The main outcome measure was identifying features that may predict submucosal invasion of mucosal lesions and predict recurrence of adenomas on follow-up surveillance colonoscopy performed at 4-6 mo.RESULTSA total of 480 patients with 500 lesions were included in the study. The median age was 68 (Inter quantile range: 14) with 52% males. The most common lesion location was ascending colon (161; 32%). Paris classification 0-IIa (Flat elevation of mucosa - 316; 63.2%); Kudo Pit Pattern IIIs (192; 38%) and Granular surface morphology (260; 52%) were most prevalent. Submucosal invasion was present in 23 (4.6%) out of 500 lesions. The independent risk factors for SMIL were Kudo Pit Pattern IIIL + IV and V (Odds ratio: 4.5; P value < 0.004) and Paris classification 0-IIc (Odds ratio: 18.2; P value < 0.01). Out of 500, 354 post-endoscopic mucosal resection scars were examined at surveillance colonoscopy. Recurrence was noted in 21.8% (77 cases).CONCLUSIONThere was overall low prevalence of SMIL in our study. Kudo pit pattern (IIIL + IV and V) and Paris classification 0-IIc were the only factors identified as an independent risk factor for submucosal invasion. The independent risk factor for recurrence was adenoma size (> 40 mm). Almost all recurrences (98.8%) were treated endoscopically.

Mo1640 A RECTUM-SPECIFIC RESECTION ALGORITHM OPTIMIZES ONCOLOGIC OUTCOMES FOR LARGE LATERALLY SPREADING LESIONS

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are complementary techniques for rectal laterally spreading lesions (RLSLs). A mechanism for appropriate technique selection has not been described. To assess whether a rectum-specific resection algorithm (RSRA), based on real-time endoscopic lesion characterization, can optimize oncologic outcomes. We evaluated the performance of an RSRA (08/2017-10/2019) (NCT04008407) compared to a universal EMR algorithm (UEA; 07/2008-07/2017) for RLSLs within a prospective observational study of LSLs ≥ 20mm. In the RSRA, RLSLs with features consistent with superficial submucosal invasive cancer (SMIC < 1000μm; S-SMIC; Kudo pit pattern Vi), or with an increased risk of SMIC (Paris 0-Is or 0-IIa+Is non-granular, Paris 0-IIa+Is granular with dominant nodular morphology) underwent ESD. The remaining RLSLs underwent EMR. Algorithm performance was evaluated by technical success (all neoplastic tissue removed at index procedure), SMIC identified after EMR, curative oncologic resection (R0 resection, S-SMIC, absence of negative histologic features), adverse events, and either endoscopic or histologic recurrence at first surveillance colonoscopy (SC1). 431 RLSLs were referred for endoscopic resection. 21 (4.9%) RLSLs had features consistent with deep SMIC (SMIC > 1000μm; D-SMIC) and were referred to surgery. One (0.2%) RLSL had a concomitant sigmoid cancer and was referred to surgery. 5 (1.2%) RLSLs had an out-of-protocol indication for ESD (D-SMIC; not fit for surgery) and were excluded from analysis. Of the remaining 404 RLSLs (114 RSRA, 290 UEA) median size was 45mm (IQR 31-60mm). In the RSRA, 62 (54.0%) and 52 (46.0%) underwent EMR and ESD, respectively. Technical success was achieved in 391 (96.8%) RLSLs (RSRA 111 (97.4%) vs. UEA 280 (96.6%); p = 0.675). Overall, SMIC was identified in 48 (11.9%) RLSLs (RSRA 13 (11.4%) vs. UEA 35 (12.1%); p = 0.852). Significant differences in SMIC after EMR (RSRA 1 (1.6%) vs. UEA 35 (12.1%); p = 0.014), curative oncologic resection (RSRA 5 (38.5%) vs. UEA 2 (5.7%); p = 0.004), and recurrence (RSRA 1 (1.7%) vs. UEA 40 (17.5%); p = 0.009) were identified. Stratifying by RLSLs which underwent EMR and margin thermal ablation, no significant difference in recurrence was identified (RSRA 1 (1.9%) vs. UEA 3 (5.4%); p = 0.618). No differences in delayed bleeding (RSRA 13 (11.4%) vs. UEA 21 (7.2%); p = 0.175), deep mural injury III-V (RSRA 6 (5.3%) vs. UEA 12 (4.1%); p = 0.622) or delayed perforation (RSRA 0 (0.0%) vs. UEA 1 (0.3%); p = 1.000) were identified. Among malignant lesions which underwent ESD, and were amenable to curative endoscopic resection, 100% (5/5) were cured. An RSRA optimizes curative oncologic outcomes for RLSLs and mitigates the risk of malignant neoplasia undergoing piecemeal resection.

P296 Quality of reporting of lesions detected at surveillance colonoscopy for IBD

Abstract Background International guidelines of ESGE and ASGE have laid out best practice for documentation of lesions at colonoscopy but few performance indicators have been proposed for surveillance colonoscopy in IBD. A recent publication has highlighted the key performance indicators for surveillance colonoscopy.1 We conducted an audit of current quality of colonoscopy reports documenting lesions detected during surveillance colonoscopy. Methods A retrospective analysis of patients who underwent colonoscopy for IBD surveillance over a five year period (2014–2019) at the Queen Elizabeth Hospital, Birmingham, UK was performed. The reports were analysed by independent academic doctors in the gastroenterology division trained in quality of endoscopic report analysis. Optimum criteria for documentation comprised lesion nature (Paris classification), size, documentation of Kudo classification and pit pattern, borders and ulceration. Results A total of 1028 colonoscopies were performed for IBD surveillance and the procedures were standardised with routine dye spraying since 2016. The mean patient age was 47.9 years (SD 16.8). Visual evidence of colonoscopic lesions was recorded in 273 cases. Key performance indicators documented for each endoscopic criterion and lesion nature is noted in the Table. Low-grade dysplasia was detected in 61 patients, and carcinoma in 4 patients; no patient had high-grade dysplasia. Benign lesions such as pseudopolyps were detected in the rest. 7 patients had sessile serrated lesions. Conclusion At IBD surveillance colonoscopy, documentation of lesions is better for the domains of size, Paris classification and Kudo pit pattern, though not perfect. We also highlight that our colonoscopic documentation of borders and presence of ulcerations is done poorly. It is important that comprehensive training is undertaken to improve documentation as it is essential for the proper choice of management of these lesions. Reference