Characterization Of Polyps Research Articles

Clinical Characterization of Fibroblastic Polyps

Introduction: Fibroblastic polyps (FPs) are a rare, recently described colorectal polyp subtype histologically characterized by the proliferation of bland spindled cells within the lamina propria. FPs are distinguishable immunohistochemically (IHC) from other mucosal polyps and are generally discovered incidentally. While considered benign and unassociated with polyposis syndromes, a paucity of clinical information exists regarding this polyp subtype. As a large tertiary endoscopy practice, we sought to describe our clinical experience in patients diagnosed with FPs. Methods: Cases were identified between Jan 1994 and May 2017 among patients 18-99 years of age at the time of diagnosis using an institutional pathology database. Clinical data was abstracted using existing clinical and endoscopic records. IHC was performed at the discretion of the reviewing pathologist and only those cases with compatible histology and supportive IHC (negative S-100, EMA, CD117) were included for review. Results: A total of 21 patients with a diagnosis of FP (n=32 polyps) were identified. Following diagnosis, none of the patients were found to have FPs on subsequent colonoscopies. The median age at FP diagnosis was 59 years (range 31-84) with 13 (62%) being male. A single FP was identified in all but one case; in the remaining case, 12 FPs were simultaneously diagnosed in a patient with Cowden syndrome. The median FP size was 4 mm (range 2-8 mm) while by configuration, 27 (84%) and 5 (16%) were sessile and pedunculated, respectively. FPs were predominately located in the left colon with 17 (53%), and 5 (16%) discovered in the rectosigmoid and descending colon, respectively. In 11(52%) cases, FPs were concomitantly diagnosed with other polyp subtypes including tubular adenoma with low-grade dysplasia (7/11), hyperplastic polyp (3/11), and sessile serrated adenoma (1/11). Among patients diagnosed with FPs, indications for colonoscopy varied; routine follow-up for known history of adenomatous polyps and initial colorectal cancer (CRC) screening were the most common in 9 (43%) and 6 (29%) patients, respectively. Conclusion: FPs are rare, predominately left-sided colonic polyps which vary between sessile and pedunculated configuration. Though predominately solitary, multiple FPs were observed in a patient with Cowden syndrome and no patients had FPs diagnosed on subsequent endoscopy. Further study is needed to elucidate the pathogenesis and significance of FPs.

Su1670 The New Basic (Bli Adenoma Serrated International Classification) Classification for Colorectal Polyp Characterization With Blue Laser Imaging

Su1670 The New Basic (Bli Adenoma Serrated International Classification) Classification for Colorectal Polyp Characterization With Blue Laser Imaging

Advances in image enhancement in colonoscopy for detection of adenomas.

High-quality colonoscopy is mandatory to prevent adenoma recurrence and colorectal cancer. In the past few years, technical advances have been developed with the purpose of improving adenoma detection rate (ADR), one of the most important validated colonoscopy quality benchmarks. Several techniques or devices are used to optimize visualization: observation techniques; add-on devices; auxiliary imaging devices; colonoscopes with increased field of view; and colonoscopes with an integrated inflatable reusable balloon. Image-enhanced endoscopy (IEE) facilitates the detection and characterization of polyps and especially nonpolypoid colorectal neoplasms. Indigo carmine is the most frequently used dye in colonoscopy as it deposits in depressed areas, improving detection of flat and depressed lesions. Virtual chromoendoscopy has emerged as an effective contrast enhancement technology without the limitation of preparing dyes and applying them through the colonoscope working channel. Narrow-band imaging (NBI) enhances the capillary pattern and surface of the mucosa using optical filters, and second-generation NBI provides a twofold brighter image than the previous system, yielding promising ADR results. Moreover, a second-generation blue laser imaging system, LASEREO, has been reported to improve not only polyp detection rate but also ADR, becoming a promising IEE modality. Herein, we describe technical advances in colonoscopy imaging and their effect on ADR.

Deep Learning for Classification of Colorectal Polyps on Whole-slide Images

Context: Histopathological characterization of colorectal polyps is critical for determining the risk of colorectal cancer and future rates of surveillance for patients. However, this characterization is a challenging task and suffers from significant inter- and intra-observer variability. Aims: We built an automatic image analysis method that can accurately classify different types of colorectal polyps on whole-slide images to help pathologists with this characterization and diagnosis. Setting and Design: Our method is based on deep-learning techniques, which rely on numerous levels of abstraction for data representation and have shown state-of-the-art results for various image analysis tasks. Subjects and Methods: Our method covers five common types of polyps (i.e., hyperplastic, sessile serrated, traditional serrated, tubular, and tubulovillous/villous) that are included in the US Multisociety Task Force guidelines for colorectal cancer risk assessment and surveillance. We developed multiple deep-learning approaches by leveraging a dataset of 2074 crop images, which were annotated by multiple domain expert pathologists as reference standards. Statistical Analysis: We evaluated our method on an independent test set of 239 whole-slide images and measured standard machine-learning evaluation metrics of accuracy, precision, recall, and F1 score and their 95% confidence intervals. Results: Our evaluation shows that our method with residual network architecture achieves the best performance for classification of colorectal polyps on whole-slide images (overall accuracy: 93.0%, 95% confidence interval: 89.0%-95.9%). Conclusions: Our method can reduce the cognitive burden on pathologists and improve their efficacy in histopathological characterization ofcolorectal polyps and in subsequent risk assessment and follow-up recommendations.

Economic value of narrow band imaging versus white light endoscopy for the characterization of diminutive polyps in the colon: systematic literature review and cost-consequence model

Aims: To demonstrate the economic implication of adopting narrow-band imaging (NBI) for the characterization of diminutive polyps in the colon from an English payer perspective.Materials and methods: A decision-tree model was undertaken to perform a cost-consequence and budget impact analysis from the NHS England perspective in the UK, over a 7-year time horizon. Clinical inputs came from the published literature (both randomized controlled trials and meta-analyses) identified through a systematic literature review, and cost inputs came from national list prices and unpublished internal market data. Deterministic sensitivity analysis (DSA) was conducted on the budget impact results to assess their robustness.Results: Optical diagnosis with NBI offered cost savings vs white light endoscopy (WLE) over 7 years due to reductions in histological exams, resections, and associated adverse events, while having minimal impact on health outcomes. Budget impact analysis demonstrated annual cost savings of £141 192 057 over 7 years, with histological exams being the biggest cost driver. DSA showed these results to be robust, but most sensitive to the cost of tariff with and without biopsy, and the cost of histological exam. Break-even analysis to explore how changing the unit cost and number of biopsies per patient would change the budget impact found NBI consistently offered net savings, even if the cost of biopsy was £0.Limitations: Although every effort was made to ensure robustness of results, as with any model, there were some limitations including a lack of published data for certain clinical inputs and potential variation between model inputs and real-life cost and market share values.Conclusions: Optical diagnosis with NBI was found to be equally effective compared with the standard of care (WLE), while potentially enabling cost savings from the NHS England perspective.

PWE-115 Detection and Characterisation of Colorectal Polyps Using High Definition White Light and I-Scan: Evidence and Delphi Process-Based Consensus Recommendations

Introduction Electronic imaging technologies such as i-Scan, Narrow Band Imaging (NBI) and Fujinon Intelligence Colour Enhancement (FICE) are increasingly used for polyp detection and characterisation, but to date, their use is limited to expert settings. I-scan is a relatively novel technology. Insufficient literature with i-scan and the lack of RCT’s hinder its implementation in clinical practice. Our goal was to review the current literature on the clinical utility of i-scan and develop evidence-based practical recommendations. Methods We conducted a systematic review on the role of high definition white-light (HDWL) and i-Scan colonoscopy for polyp detection and characterisation. A series of evidence-based statements were developed and put through anonymous voting along the lines of a modified Delphi process. A one day consensus meeting was held (June 20, 2015, Milan). Each statement was voted until consensus (i.e >80% agreement) was achieved or rejection agreed. GRADE recommendations were assigned to the agreed statements. Results The Consensus Panel consisted of 11 international experts. In total, 11 statements were proposed, of which 9 achieved consensus: HDWL is recommended rather than standard definition (SD) for the detection and characterisation of colorectal polyps; HDWL + i-Scan improves polyp and adenoma detection rates; HDWL + i-Scan are superior to HDWL alone for the optical diagnosis of colorectal polyps; HDWL + i-Scan in expert hands meet the ASGE PIVI standards for the optical diagnosis of diminutive polyps; HDWL+i-Scan in non-expert hands do not meet the ASGE PIVI standards for the optical diagnosis of diminutive polyps; Optical diagnosis of polyps with i-Scan has a learning curve and needs systematic training; The performance of i-Scan for real time characterisation of colorectal polyps is similar to NBI & FICE. Two statements failed to achieve consensus: HDWL alone can be effective for the in-vivo characterisation of polyps in expert hands; The adenoma detection rate is comparable when using HDWL + i-scan versus chromoendoscopy. Conclusion The Consensus Panel proposes evidence-based recommendations for the detection and characterisation of colorectal polyps using high-definition white light endoscopy and i-scan, to facilitate implementation of this technology in clinical practice. Areas of uncertainty, controversy and future research needs are addressed. Disclosure of Interest None Declared

Tu1031 Detection and Characterization of Colorectal Polyps Using High Definition White Light and i-Scan: Evidence and Delphi Process-Based Consensus Recommendations

Tu1031 Detection and Characterization of Colorectal Polyps Using High Definition White Light and i-Scan: Evidence and Delphi Process-Based Consensus Recommendations

Mo1743 Accuracy and Inter-Observer Agreement for Characterization of Colonic Polyps Using the New Optical Enhancement -iSCAN Closefocus™ Colonoscope

Mo1743 Accuracy and Inter-Observer Agreement for Characterization of Colonic Polyps Using the New Optical Enhancement -iSCAN Closefocus™ Colonoscope

Polyp Detection, Characterization, and Management Using Narrow-Band Imaging with/without Magnification.

Narrow-band imaging (NBI) is a new imaging technology that was developed in 2006 and has since spread worldwide. Because of its convenience, NBI has been replacing the role of chromoendoscopy. Here we review the efficacy of NBI with/without magnification for detection, characterization, and management of colorectal polyps, and future perspectives for the technology, including education. Recent studies have shown that the next-generation NBI system can detect significantly more colonic polyps than white light imaging, suggesting that NBI may become the modality of choice from the beginning of screening. The capillary pattern revealed by NBI, and the NBI International Colorectal Endoscopic classification are helpful for prediction of histology and for estimating the depth of invasion of colorectal cancer. However, NBI with magnifying colonoscopy is not superior to magnifying chromoendoscopy for estimation of invasion depth. Currently, therefore, chromoendoscopy should also be performed additionally if deep submucosal invasive cancer is suspected. If endoscopists become able to accurately estimate colorectal polyp pathology using NBI, this will allow adenomatous polyps to be resected and discarded; thus, reducing both the risk of polypectomy and costs. In order to achieve this goal, a suitable system for education and training in in vivo diagnostics will be necessary.

Prospective evaluation of a simplified narrowband imaging scoring system for a differential diagnosis of colorectal lesions.

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. 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. 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). 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.

Learning Curves for the Real-Time Histologic Characterization of Diminutive Colorectal Polyps With Narrow Band Imaging (NBI) Using Cumulative Summation Analysis (CUSUM): Implications for Resect and Discard Strategy: ACG Governors Award for Excellence in Clinical Research

Learning Curves for the Real-Time Histologic Characterization of Diminutive Colorectal Polyps With Narrow Band Imaging (NBI) Using Cumulative Summation Analysis (CUSUM): Implications for Resect and Discard Strategy: ACG Governors Award for Excellence in Clinical Research

Blue laser imaging endoscopy system for the early detection and characterization of colorectal lesions: a guide for the endoscopist.

Blue laser imaging is a new system for image-enhanced endoscopy using laser light. Blue laser imaging utilizes two monochromatic lasers (410 and 450 nm) instead of xenon light. A 410 nm laser visualizes vascular microarchitecture, similar to narrow band imaging, and a 450 nm laser provides white light by excitation. According to three recently published reports, the diagnostic ability of polyp characterization using blue laser imaging compares favorably with narrow band imaging. No published data are available to date regarding polyp detection with blue laser imaging. However, blue laser imaging has the possibility to increase the detection of colorectal polyps by depicting brighter and clearer endoscopic images, even at a distant view, compared with first-generation image-enhanced endoscopy. A clinical trial to compare the detection between blue laser imaging and xenon light is warranted.

Narrow-band imaging in the prediction of surveillance intervals after polypectomy in community practice.

It has been proposed that the use of narrow-band imaging (NBI) for real-time histological assessment to determine postpolypectomy surveillance intervals is a cost-effective approach to the management of diminutive polyps. However, significant discrepancies in NBI performance have been observed among endoscopists; hence, professional societies recommend training, monitoring, and auditing. The aim of the present study was to evaluate the performance of real-time optical diagnosis for diminutive polyps after the inclusion of this approach in an internal quality assurance program, in order to assess its applicability in clinical practice Patients and methods: Four endoscopists attended periodic training sessions on NBI assessment of polyp histology before and during the study. Performance was audited and periodic feedback was provided. The accuracy of high-confidence NBI evaluation for polyps ≤ 5 mm in predicting surveillance intervals according to the European and US guidelines, and the negative predictive value (NPV) for adenoma in the rectosigmoid were calculated and compared with recommended thresholds (90 % agreement and 90 % NPV, respectively). Overall, 284 outpatients (mean age 61.3 ± 18.2 years; 63 % males) were enrolled. A total of 656 polyps were detected, 465 of which (70.9 %) were diminutive (70.5 % adenomas). Sensitivity, specificity, positive and negative predictive values, and accuracy of high-confidence NBI predictions for adenoma in diminutive lesions were 95.3 %, 83.5 %, 93.5 %, 87.6 %, and 91.9 %, respectively. High-confidence characterization of diminutive polyps predicted the correct surveillance interval in 95.8 % and 93.3 % of cases according to European and American guidelines, respectively. NPV for adenoma in the rectosigmoid was 91.3 % For community settings in which endoscopists are adequately trained and performance is periodically audited, real-time optical diagnosis for diminutive polyps is sufficiently accurate to avoid postpolypectomy histological examination of resected lesions, or to leave rectosigmoid hyperplastic polyps in place. Trial registered at ClinicalTrials.gov (NCT02196402).

PTH-011 Defining the optimal i-scan settings for small colonic polyp characterisation – results from a large prospective series: Abstract PTH-011 Table 1

Introduction Characterisation of small colonic polyps has been identified as a key goal for advanced imaging modalities by the ASGE and ESGE. Pentax i-Scan is an endoscopic digital contrast technology shown to be an accurate tool for characterising small colonic polyps in-vivo. I-Scan combines features which accentuate dark-light borders (surface and contrast enhancement, SE/CE) and suppression of red light whist enhancing blue/green light (tone enhancement, TE). The optimal settings for use of i-Scan in the colon have yet to be determined. Method High quality digital images of 100 small colonic polyps were recorded as part of a prospective study (NCT 01761279). Images of each polyp were recorded in 3 i-Scan modes: i-Scan 1 (SE/CE), i-Scan 2 (TE) and i-Scan 3 (SE/CE/TE). Randomised images were viewed by 2 blinded endoscopists who rated visibility of diagnostic features and predicted polyp histology (neoplastic vs non-neoplastic). Results The proportion of adenomas rated as having visible pericryptal vessels were 59%, 81% and 82% for i-Scan 1, 2 and 3 respectively. The differences between i-Scan 1 and 2 (P = 0.001) and i-Scan 1 and 3 (P The difference in proportion of adenomas with no visible surface pattern between i-Scan 1 and 2 was statistically significant (26% vs 8%, P = 0.001), as was the difference between i-Scan 1 and 3 (26% vs 9%, P = 0.003). There was no significant difference between i-Scan 2 and 3 (8% vs 9%, P = 1.00). Mean sensitivity for adenomatous histology between the two endoscopists was 69% for polyps viewed with i-Scan 1. Compared to i-Scan 1 assessments sensitivity was significantly higher with i-Scan 2 (86%, P = 0.006 for comparison), and with i-Scan 3 (87%, P = 0.003 for comparison). There was no significant difference in sensitivity between i-Scan 2 and i-Scan 3 assessments (86% vs 87%, P = 1.000). No significant differences in specificity were found between the 3 i-Scan modes (i-Scan 1 vs i-Scan 2 P = 0.828, i-Scan 1 vs i-Scan 3 P = 1.000, i-Scan 1 vs i-Scan 3 P = 1.000). Overall accuracy increased from 79% with i-Scan 1 to 86.5% with i-Scan 2 and 87.5% with i-Scan 3. There was no significant difference in overall accuracy between i-Scan 1 and i-Scan 2 (P = 0.063) or i-Scan 2 and i-Scan 3 (P = 0.882). However there was a significant difference between i-Scan 1 and i-Scan 3 assessments (P = 0.032). Conclusion Tone enhancement appears to be the most effective component of the i-Scan system for accurate small colonic polyp characterisation, with no additional benefit from the addition of surface/contrast enhancement. Disclosure of interest None Declared.

Sa1602 Endoscopic Characterization of Small Colorectal Polyps Using Blue LASER Imaging

Blue laser imaging (BLI) is a new system for image-enhanced endoscopy using laser light (Fujifilm, Japan). In BLI, 2 monochromatic lasers (410nm and 480nm) are applied instead of xenon light. A 410nm laser visualizes vascular microarchitecture, similar to narrow band imaging (NBI, Olympus), and a 480nm laser provides white light by excitation. The aim of this study was to evaluate performance characteristics of BLI for the endoscopic characterization of small polyps.

Advanced endoscopic imaging for enhanced detection and characterization of colon polyps and IBD

Advanced endoscopic imaging for enhanced detection and characterization of colon polyps and IBD

Physician assessment and management of complex colon polyps: a multicenter video-based survey study.

The management of complex colorectal polyps varies in practice. Accurate descriptions of the endoscopic appearance by using a standardized classification system (Paris classification) and size for complex colon polyps may guide subsequent providers regarding curative endoscopic resection vs. need for surgery. The accuracy of this assessment is not well defined. Furthermore, the factors associated with decisions for endoscopic vs. surgical management are unclear. To characterize the accuracy of physician assessment of polyp morphology, size, and suspicion for malignancy among physician subspecialists performing colonoscopy and colon surgery. In addition, we aimed to assess the influence of these polyp characteristics as well as physician type and patient demographics on recommendations for endoscopic vs. surgical resection of complex colorectal polyps. An online video-based survey was sent to gastroenterologists (GIs) and gastrointestinal surgeons affiliated with six tertiary academic centers. The survey consisted of high-definition video clips (30-60 s) of six complex colorectal polyps (one malignant) and clinical histories. Respondents were blinded to histology. Respondents were queried regarding polyp characteristics, suspicion for malignancy, and recommendations for resection. The survey response rate was 154/317 (49%). Seventy-eight percent of respondents were attending physicians (91 GIs and 29 surgeons) and 22% were GI trainees. Sixteen percent of respondents self-identified as specialists in complex polypectomy. Accurate estimation of polyp size was poor (28.4%) with moderate interobserver agreement (k=0.52). Accuracy for Paris classification was 47.5%, also with moderate interobserver agreement (k=0.48). Specialists in complex polypectomy were most accurate, whereas surgeons were the least accurate in assigning Paris classification (66.0 vs. 28.7%, P<0.0001). Specialists in complex polypectomy were most likely to correctly identify the malignant lesion compared with other physicians (87.5 vs. 56.2%, P=0.008). Surgical removal of colon adenomas was recommended least frequently by specialists in complex polypectomy (3.1%) compared with nonspecialists in complex polypectomy (13.3%); surgeons were most likely to recommend surgical resection (17.2%, P=0.009). There were no differences in recommendations for endoscopic vs. surgical resection observed on the basis of years in practice, polyp morphology (polypoid vs. nonpolypoid), polyp location (right vs. left colon), or patient ASA class. In this large survey of GIs and surgeons, physician specialty was strongly associated with accurate polyp characterization and a recommendation for endoscopic resection of complex polyps. Surgeons were most likely to recommend surgical resection of complex nonmalignant colorectal polyps compared with specialists in complex polypectomy who were the least likely. Therefore, collaboration with specialists in complex polypectomy may be helpful in determining the appropriate management of complex colon polyps. Further teaching is needed among all specialists to improve accurate communication and ensure optimal management of these lesions.

Sa1945 Molecular Characterization of Serrated Polyps Can Differentiate More Advanced Lesions

Patients With Multiple Adenomatous Polyps: Causes, Characteristics and Management Recommendations Carla Guarinos, Eva Hernandez-Illan, Miriam Juarez-Quesada, Maria Rodriguez-Soler, Cecilia M. Egoavil, Lucia Perez-Carbonell, Ramon Salas-Rico, Joaquin Cubiella, Francisco Rodriguez-Moranta, Luisa De-Castro, Luis Bujanda, Anna Serradesanferm, David NicolasPerez, Maite Herraiz, Fernando Fernandez-Banares, Alberto Herreros de Tejada, Elena Aguirre, Judith Balmana, Angeles Pizarro, Adela Castillejo, Cristina Alenda, Artemio Paya, Jose-Luis Soto, Rodrigo Jover

Mo1496 Is It Really so Easy to Learn Histologic Characterization of Diminutive Polyps by Narrow Band Imaging? Preliminary Results of Endoscopists' and Nurses' Performances

not clearly, score3; clearly visible). The average scores of 5 endoscopists were statistically compared between the both technologies. Study2; The visualization of bleeding points were assessed by using 50 Dual Red Imaging movies and 50 WLI movies. The scores (1-3 scale) for the visibility of bleeding points were measured for all movies using the same criteria as study1. The average scores of 5 endoscopists were statistically compared between the both technologies. Results: Study1; The average score for the visualization of thick blood vessels in deeper tissue was significantly higher in Dual Red Imaging than in WRI (average score; Dual Red Imaging 2.0, WLI 1.4, pZ0.0008). Study2; Dual Red Imaging was statistically superior to WLI in terms of the visibility of bleeding points as well (average score; Dual Red Imaging 2.6, WLI 1.9, pZ0.0004). Conclusion: In this study, it was shown that Dual Red Imaging would offer very useful images which can make it easy to detect thick blood vessels in deeper tissue and bleeding points compared with WLI. Therefore, Dual Red Imaging has the potential to decrease the risk of bleeding by recognizing thick blood vessels and to facilitate endoscopic hemostasis by visualizing bleeding points clearly.

Mo1539 Use of Blue LASER Imaging for Identification of Colorectal Cancer With Deep Submucosal Invasion

Blue laser imaging (BLI) is a new system of image enhanced endoscopy using laser light (Fujifilm, Japan). In BLI, 2 monochromatic lasers (410nm and 480nm) are applied instead of xenon light. A 410nm laser visualizes vascular microarchitecture on the mucosal surface because its wavelength represents the absorption spectra of vessels, and a 480nm laser provides white light by excitation. BLI may be combined with optical magnification for polyp characterization and T staging for cancer. The aim of this study was to investigate the BLI findings associated with deep submucosal invasion in colorectal cancers.