Clinical usefulness of narrow band imaging magnifying colonoscopy for assessing ulcerative colitis-associated cancer/dysplasia

Clinical usefulness of image-enhanced endoscopy for the diagnosis of ulcerative colitis-associated neoplasia

Patients with a long history of ulcerative colitis (UC) are at risk of developing a significant complication known as UC-associated neoplasia (UCAN). To reduce the risk of UCAN and the associated mortality, the current guidelines recommend initiating surveillance colonoscopy 8-10 years after confirmation of UC diagnosis. In recent years, advancements in endoscopic diagnostic technologies, including magnifying and image-enhancing techniques, have allowed for the production of high-contrast images that emphasize mucosal structures, vascular patterns, and color tones. Recently, image-enhanced endoscopy technologies have become available and offer the potential to improve the qualitative endoscopic assessment of UCAN. The use of high-definition chromoendoscopy enables the evaluation of subtle mucosal patterns in the colon. Magnifying narrow-band imaging facilitates the visualization of mucosal vascular structures. Texture and color enhancement imaging processes structure, color tone, and brightness aspects more appropriately, whereas linked color imaging optimizes the emphasis on mucosal and vascular redness. Both techniques are expected to excel in the depiction of subtle color variations and mucosal changes characteristic of UCAN. This article provides an overview of the current status and future challenges regarding the use of various image-enhanced endoscopy techniques in the diagnosis of UCAN.

Characteristics of flat-type ulcerative colitis-associated neoplasia on chromoendoscopic imaging with indigo carmine dye spraying

OBJECTIVES

Despite recent advances in endoscopic equipment and diagnostic techniques, early detection of ulcerative colitis-associated neoplasia (UCAN) remains difficult because of the complex background of the inflamed mucosa of ulcerative colitis and the morphologic diversity of the lesions. We aimed to describe the main diagnostic patterns for UCAN in our cohort, including lateral extension surrounding flat lesions.

METHODS

Sixty-three lesions in 61 patients with flat-type dysplasia that were imaged with dye chromoendoscopy (DCE) were included in this analysis. These DCE images were analyzed to clarify the dye-chromoendoscopic imaging characteristics of flat dysplasia, and the lesions were broadly classified into dysplastic and nondysplastic mucosal patterns.

RESULTS

Dysplastic mucosal patterns were classified into two types: small round patterns with round to roundish structures, and mesh patterns with intricate mesh-like structures. Lesions with a nondysplastic mucosal pattern were divided into two major types: a ripple-like type and a gyrus-like type. Of note, 35 lesions (55.6%) had a small round pattern, and 51 lesions (80.9%) had some type of mesh pattern. About 70% of lesions with small round patterns and 49% of lesions with mesh patterns were diagnosed as high-grade dysplasia or carcinoma, while about 30% of lesions with small round patterns and 51% of lesions with mesh patterns were diagnosed as low-grade dysplasia.

CONCLUSION

When a characteristic mucosal pattern, such as a small round or mesh pattern, is found by DCE, the possibility of UCAN should be considered.

Frequency and Predictors of Dysplasia in Pseudopolyp-like Colorectal Lesions in Patients with Long-Standing Inflammatory Bowel Disease

Current endoscopic surveillance programs do not consider inflammatory bowel disease (IBD)-associated post-inflammatory polyps (pseudopolyps) per se clinically relevant, even though their presence seems to increase the risk of colorectal cancer (CRC). However, it remains unclear whether the link between pseudopolyps and CRC is indirect or whether some subsets of pseudopolyp-like lesions might eventually undergo neoplastic transformation. This study aimed to assess the frequency and predictors of dysplasia in pseudopolyp-like lesions in a population with long-standing colonic IBD. This was a retrospective, single-center study including patients with a colonic IBD (median disease duration of 192 months) and at least a pseudopolyp-like lesion biopsied or resected in the period from April 2021 to November 2022. One hundred and five pseudopolyps were identified in 105 patients (80 with ulcerative colitis and 25 with Crohn's disease). Twenty-three out of 105 pseudopolyp samples (22%) had dysplastic foci, and half of the dysplastic lesions were hyperplastic. Multivariate analysis showed that the age of the patients (odds ratio (OR) 1.1; p = 0.0012), size (OR 1.39; p = 0.0005), and right colonic location (OR 5.32; p = 0.04) were independent predictors of dysplasia, while previous exposure to immunosuppressors/biologics and left colonic location of the lesions were inversely correlated to dysplasia (OR 0.11; p = 0.005, and OR 0.09; p = 0.0008, respectively). No differences were seen between ulcerative colitis and Crohn's disease patients. Lesions with a size greater than 5 mm had a sensitivity of 87% and a specificity of 63% to be dysplastic. These data show that one-fourth of pseudopolyp-like lesions evident during surveillance colonoscopy in patients with longstanding IBD bear dysplastic foci and suggest treating such lesions properly.

Use of advanced endoscopic technology for optical characterization of neoplasia in patients with ulcerative colitis: Systematic review

OBJECTIVES

Advances in endoscopic technology, including magnifying and image-enhanced techniques, have been attracting increasing attention for the optical characterization of colorectal lesions. These techniques are being implemented into clinical practice as cost-effective and real-time approaches. Additionally, with the recent progress in endoscopic interventions, endoscopic resection is gaining acceptance as a treatment option in patients with ulcerative colitis (UC). Therefore, accurate preoperative characterization of lesions is now required. However, lesion characterization in patients with UC may be difficult because UC is often affected by inflammation, and it may be characterized by a distinct "bottom-up" growth pattern, and even expert endoscopists have relatively little experience with such cases. In this systematic review, we assessed the current status and limitations of the use of optical characterization of lesions in patients with UC.

METHODS

A literature search of online databases (MEDLINE via PubMed and CENTRAL via the Cochrane Library) was performed from 1 January 2000 to 30 November 2021.

RESULTS

The database search initially identified 748 unique articles. Finally, 25 studies were included in the systematic review: 23 focused on differentiation of neoplasia from non-neoplasia, one focused on differentiation of UC-associated neoplasia from sporadic neoplasia, and one focused on differentiation of low-grade dysplasia from high-grade dysplasia and cancer.

CONCLUSIONS

Optical characterization of neoplasia in patients with UC, even using advanced endoscopic technology, is still challenging and several issues remain to be addressed. We believe that the information revealed in this review will encourage researchers to commit to the improvement of optical diagnostics for UC-associated lesions.

Magnifying endoscopy is useful for tumor border diagnosis in ulcerative colitis patients

BACKGROUND AND AIMS

Endoscopic resection (ER) is feasible for well-circumscribed tumors in patients with ulcerative colitis (UC); however, the specific manner for diagnosis of the tumor border is unclear. We evaluated the efficacy of magnifying endoscopy (ME) for the diagnosis of tumor borders in UC.

METHODS

We analyzed endoscopically or surgically resected tumors in UC patients in whom both chromoendoscopy (CE) and ME were performed, retrospectively. We classified the tumors based on tumor border visibility and evaluated tumor's characteristics and ER outcomes.

RESULTS

We examined 100 tumors from 76 UC patients (66 distinct and 34 indistinct on CE). In 22 (65%) indistinct tumors on CE, ME improved the tumor border visibility. Compared with distinct tumors on CE, nonpolypoid and large tumors were more common in indistinct tumors on CE. In indistinct tumors even on ME, flat or depressed morphologies and type V pit were more frequently than in other groups. Sixty-five distinct tumors on CE and 18 distinct tumors on ME alone were treated endoscopically, and their R0 resection rate were 91% and 95% (p > 0.99).

CONCLUSIONS

ME can improve the tumor border visibility in UC, and ER is feasible for tumors whose border can be visualized on ME.

Endoscopic Surveillance in Inflammatory Bowel Diseases: Selecting a Suitable Technology

In the treat-to-target era, endoscopy has become the backbone of the assessment of remission, defined as mucosal healing, in inflammatory bowel disease (IBD) patients. Current recommendations indicate that endoscopic procedures should be performed with high-definition white-light endoscopy (HD-WLE), as it guarantees the best possible visualization of the mucosa. With respect to endoscopic surveillance, the preventive strategy for dysplasia and colorectal cancer (CRC) in long-standing IBD, is the use of dye-chromoendoscopy (DCE), which enhances the mucosal pattern of the colonic walls. DCE has been established as the gold standard for dysplasia detection and is at present incorporated in all international guidelines. Over the past years, novel technologies, such as high-definition endoscopic imaging, and optical and digital enhancement tools have revolutionized the quality and level of fine details of vascular and mucosal patterns. These endoscopic images have the ambition to reflect histological changes for suspected neoplastic lesions and inflammation or healing and are emerging as potential alternatives to DCE. Indeed, the comparison of DCE with high-definition imaging is an open issue that deserves further investigation. We aimed to examine and summarize the technical aspects and the current evidence on endoscopic technologies with a specific focus on the surveillance in IBD patients.

Evolving roles of magnifying endoscopy and endoscopic resection for neoplasia in inflammatory bowel diseases

Magnifying endoscopy is a useful technique to differentiate neoplasia from non-neoplastic lesions. Data regarding the clinical utility of magnifying endoscopy for neoplasia in patients with inflammatory bowel disease (IBD) has been emerging. While Kudo’s pit pattern types III-V are findings suggestive of neoplasia in non-IBD patients, these pit patterns are predictive of IBD-associated neoplasia as well. However, active chronic inflammatory processes, particularly regenerative changes, can mimic neoplastic pit patterns and may affect a meticulous evaluation of pit pattern diagnosis in patients with IBD. The clinical evidence regarding the utility of magnifying endoscopy with narrow band imaging or endocytoscopy has also been evolving in regard to the diagnosis of IBD-associated neoplasia. These advanced endoscopic techniques are promising for multiple reasons; not only for making an accurate diagnosis of neoplasia, but also in determining if endoscopic resection is appropriate for such lesions in patients with IBD. In this review, we discuss the diagnostic accuracy and limitations of magnifying endoscopy in assessing IBD-associated neoplasia and examine the feasibility and outcomes of endoscopic resection for these lesions.

Diagnostic performance of endoscopic classifications for neoplastic lesions in patients with ulcerative colitis: A retrospective case-control study

BACKGROUND

It is unclear whether the Japan Narrow-Band Imaging Expert Team (JNET) classification and pit pattern classification are applicable for diagnosing neoplastic lesions in patients with ulcerative colitis (UC).

AIM

To clarify the diagnostic performance of these classifications for neoplastic lesions in patients with UC.

METHODS

This study was conducted as a single-center, retrospective case-control study. Twenty-one lesions in 19 patients with UC-associated neoplasms (UCAN) and 23 lesions in 22 UC patients with sporadic neoplasms (SN), evaluated by magnifying image-enhanced endoscopy, were retrospectively and separately assessed by six endoscopists (three experts, three non-experts), using the JNET and pit pattern classifications. The results were compared with the pathological diagnoses to evaluate the diagnostic performance. Inter- and intra-observer agreements were calculated.

RESULTS

In this study, JNET type 2A and pit pattern type III/IV were used as indicators of low-grade dysplasia, JNET type 2B and pit pattern type V_I low irregularity were used as indicators of high-grade dysplasia to shallow submucosal invasive carcinoma, JNET type 3 and pit pattern type V_I high irregularity/V_N were used as indicators of deep submucosal invasive carcinoma. In the UCAN group, JNET type 2A and pit pattern type III/IV had a low positive predictive value (PPV; 50.0% and 40.0%, respectively); however, they had a high negative predictive value (NPV; 94.7% and 100%, respectively). Conversely, in the SN group, JNET type 2A and pit pattern type III/IV had a high PPV (100% for both) but a low NPV (63.6% and 77.8%, respectively). In both groups, JNET type 3 and pit pattern type V_I-high irregularity/V_N showed high specificity. The inter-observer agreement of JNET classification and pit pattern classification for UCAN among experts were 0.401 and 0.364, in the same manner for SN, 0.666 and 0.597, respectively. The intra-observer agreements of JNET classification and pit pattern classification for UCAN among experts were 0.387, 0.454, for SN, 0.803 and 0.567, respectively.

CONCLUSION

The accuracy of endoscopic diagnosis using both classifications was lower for UCAN than for SN. Endoscopic diagnosis of UCAN tended to be underestimated compared with the pathological results.

Colorectal Dysplasia and Cancer Surveillance in Ulcerative Colitis

Ulcerative colitis (UC) is a risk factor for the development of inflammation-associated dysplasia or colitis-associated neoplasia (CAN). This transformation results from chronic inflammation, which induces changes in epithelial proliferation, survival, and migration via the induction of chemokines and cytokines. There are notable differences in genetic mutation profiles between CAN in UC patients and sporadic colorectal cancer in the general population. Colonoscopy is the cornerstone for surveillance and management of dysplasia in these patients. There are several modalities to augment the quality of endoscopy for the better detection of dysplastic or neoplastic lesions, including the use of high-definition white-light exam and image-enhanced colonoscopy, which are described in this review. Clinical practice guidelines regarding surveillance strategies in UC have been put forth by various GI societies, and overall, there is agreement between them except for some differences, which we highlight in this article. These guidelines recommend that endoscopically detected dysplasia, if feasible, should be resected endoscopically. Advanced newer techniques, such as endoscopic mucosal resection and endoscopic submucosal dissection, have been utilized in the treatment of CAN. Surgery has traditionally been the mainstay of treating such advanced lesions, and in cases where endoscopic resection is not feasible, a proctocolectomy, followed by ileal pouch-anal anastomosis, is generally recommended. In this review we summarize the approach to surveillance for cancer and dysplasia in UC. We also highlight management strategies if dysplasia is detected.

[Position paper on endoscopic reporting in IBD]

The complete and reliable documentation of endoscopic findings make up the crucial foundation for the treatment of patients with inflammatory bowel diseases such as Crohn´s disease and ulcerative colitis. These findings are, on the one hand, a prerequisite for therapeutic decisions and, on the other hand, important as a tool for assessing the response to ongoing treatments. Endoscopic reports should, therefore, be recorded according to standardized criteria to ensure that the findings of different endoscopists can be adequately compared and that changes in the course of the disease can be traced back. In consideration of these necessities, fifteen members of the Imaging Working Group of the German Kompetenznetz Darmerkrankungen have created a position paper proposing a structure and specifications for the documentation of endoscopic exams. In addition to the formal report structure, the recommendations address a large number of attributes of acute and chronic inflammatory alterations as well as endoscopically detectable complications, which are explained in detail and illustrated using exemplary images. In addition, more frequently used endoscopic activity indices are presented and their use in everyday clinical practice is discussed.

Clinical usefulness of linked color imaging for evaluation of endoscopic activity and prediction of relapse in ulcerative colitis

PURPOSE

In the treatment of ulcerative colitis (UC), accurate evaluation of UC activity is important to achieve mucosal healing. We sought to investigate the clinical utility of linked color imaging (LCI) for the evaluation of endoscopic activity and prediction of relapse in UC patients.

METHODS

We enrolled 72 consecutive UC patients in remission who underwent colonoscopy at our institution between September 2016 and October 2018. The relationship between the presence of redness in white light imaging (WLI) and LCI and histopathological inflammation (Geboes score: GS) at 238 biopsy sites was examined. We also assessed the presence or absence of planar redness in the entire rectum as ± and classified the patients into three groups according to the combination of WLI/LCI: A: WLI-/LCI-, B: WLI-/LCI+, and C: WLI+/LCI+. The relationship between WLI/LCI classification and relapse in 64 patients followed up for more than 12 months from initial colonoscopy was assessed and compared to the Mayo endoscopic subscore (MES).

RESULTS

A GS of 0 or 1 accounted for 89% of WLI/LCI non-redness sites, while a GS of 2 or 3 accounted for 42% of WLI non-redness/LCI redness sites. LCI findings were significantly correlated with GS. During follow-up, 10 patients in group C and four patients in group B relapsed, but none in group A. Non-relapse rates were significantly correlated with WLI/LCI classification, but not with MES.

CONCLUSION

LCI is a useful modality for accurate assessment of endoscopic activity and prediction of relapse in UC by detecting mild inflammation unrecognizable by WLI.

Genomic Landscape of Early-stage Colorectal Neoplasia Developing From the Ulcerative Colitis Mucosa in the Japanese Population

BACKGROUNDS

Colorectal neoplasias (CRN)s developing from the ulcerative colitis (UC) mucosa include both colitic and sporadic neoplasias. Although several genomic analyses of advanced colitis-associated cancer are available, such studies do not distinguish between colitic and sporadic cases, and the early-stage genomic alterations involved in the onset of colitic cancer remain unclear. To address this, we performed a genomic analysis of early-stage CRN developing from the UC mucosa (CRNUC).

METHODS

We extracted DNA from 36 early-stage CRNUCs (T1 cancer, 10; dysplasia, 26) from 32 UC patients and performed targeted sequencing of 43 genes commonly associated with colitis-associated cancer and compared the results with sequencing data from the Japanese invasive colitis-associated cancer.

RESULTS

The most frequently mutated gene in the CRNUC cohort was APC (mutated in 47.2% of the cases), followed by TP53 (44.4%), KRAS (27.8%), and PRKDC (27.8%). None of the TP53 mutations occurred at any of the hotspot codons. Although the TP53 mutations in The Cancer Genome Atlas of Colorectal Cancer were dispersed throughout the gene, those detected here in CRNUC cases were concentrated in the amino terminal part of the DNA-binding domain. Interestingly, the mutations in KRAS and TP53 were mutually exclusive in CRNUC, and CRNUCs with KRAS mutations had histologically serrated lesions in the gland duct. Mayo endoscopic subscore was higher in TP53-mutated CRNUCs and lower in KRAS-mutated CRNUCs.

CONCLUSIONS

Our findings suggest that early-stage CRNUC can be classified into 2 groups: those developing through the carcinogenic pathway via TP53 mutations and those developing through the carcinogenic pathway via KRAS mutations.

Endoscopic surveillance of colorectal cancer in inflammatory bowel diseases: a review of the literature

INTRODUCTION

The risk of colorectal cancer (CRC) in patients with inflammatory bowel diseases (IBD) is higher compared to the general population and it is related to the type, severity, duration, and extension of the disease.

AREAS COVERED

This review aims to highlight current evidence from the literature supporting the role of endoscopic surveillance of CRC in patients with IBD.

EXPERT OPINION

Even in the absence of randomized controlled trials (RCTs), evidence from the literature supports the effectiveness of endoscopic surveillance in reducing IBD-related CRC incidence and mortality. As a consequence, current guidelines recommend colonoscopy 8-10 years after disease or symptom onset in all patients with ulcerative colitis (UC) and Crohn's disease (CD) involving at least one-third of the colon and agree on the necessity of annual surveillance in high-risk patients. Nevertheless, an overall agreement on the optimal intervals for surveillance of low-intermediate risk patients is absent and 2-5 year intervals have been proposed. In the near future, further studies are needed to assess the most effective intervals and tailor the surveillance based on the personal risk profile. Additionally, further efforts should be made to evaluate the role of noninvasive tests as primary screening, thus avoiding unnecessary colonoscopies.

Improving quality of care in endoscopy of inflammatory bowel disease: can we do better?

INTRODUCTION

Endoscopy plays a key role in the management of inflammatory bowel disease (IBD). There is an increased need for quality assurance programs that evaluate the quality, safety and patient experiences of endoscopy, by assessing procedural and clinical outcomes.

AREAS COVERED

This review aims to summarize the most important quality indicators of endoscopy in IBD patients and could serve as the basis to improve quality endoscopic procedures and patients' perception of endoscopy in the future. However, further studies and consensus reports are necessary to standardize the quality of care in the endoscopy unit of all IBD centers.

EXPERT COMMENTARY

Developing an understanding of the patient-reported perception is important for both clinicians and patients, as it facilitates patient engagement with their care. Moreover, implementing education in reporting is crucial f and the use of verifiable databases, generated from electronic reporting systems, should be encouraged rather than unverified self-reporting, to have greater validity for documenting and to formally evaluate endoscopic practice data with audits. The use of artificial intelligence may improve the quality of endoscopy, by increasing the adenoma detection rate and helping endoscopists in the challenging differentiation between inflammatory and neoplastic lesions.

Endoscopic alterations in Peyer's patches in patients with ulcerative colitis: A prospective, multicenter study

BACKGROUND AND AIM

Peyer's patches (PPs) play a major role in intestinal mucosal immunity; however, their role in ulcerative colitis (UC) is not well investigated. We evaluated endoscopic features of PPs on narrow-band imaging with magnifying endoscopy (NBI-ME) and investigated their association with clinical factors.

METHODS

We prospectively recruited 105 patients with UC, 18 with Crohn's disease, 16 with disease control, and 33 healthy control subjects at three institutions from 2014 to 2017. NBI-ME images of the villi of PPs were evaluated according to the Villi Index, and patients were divided into the Villi Index low (L) and high (H) types. The 1-year sustained clinical remission rate was evaluated between L-type and H-type PPs in patients with UC.

RESULTS

The proportions of patients with H-type PPs were significantly higher among UC, Crohn's disease, and disease control patients than among healthy control patients (P = 0.0125, 0.018, 0.0007). In UC, age, gender, endoscopic score, and extent of disease involvement were not significantly different between L-type and H-type PPs, whereas the sustained clinical remission rate was significantly higher in L-type PPs than in H-type PPs (88% [57/65] vs 65% [17/26], P = 0.019). Multivariate analysis revealed that the L type of PPs was a significant factor for sustained clinical remission (odds ratio 3.8, 95% confidence interval 1.1-12.9, P = 0.033).

CONCLUSIONS

Patients with UC showed endoscopic alterations in PPs on NBI-ME, and highly altered appearance of PPs can be associated with a high risk of clinical relapse in patients with UC.

Improving the quality of surveillance colonoscopy in inflammatory bowel disease

Several recommendations have addressed the topic of improving the quality of surveillance colonoscopy in inflammatory bowel disease. However, there is variation between these recommendations, in part due to the absence of well-defined quality indicators, suggesting that these quality indicators should be studied and developed. We did a systematic review of evidence related to surveillance colonoscopy in inflammatory bowel disease to look at the different variables in this practice and offer a critique of the quality control measures before, during, and after the procedure. We identified several key quality measures that could be adopted in clinical practice, including control of inflammation, optimal bowel preparation, ideal time allocation, training, sedation, detection and characterisation of lesions, therapeutic management of the lesions, and colonoscopic reports. However, further primary research and consensus reports are needed to continue developing roadmaps at a global level.

Narrow Band Imaging for Surveillance in Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

BACKGROUND

The role of narrow band imaging (NBI) for surveillance colonoscopy in patients with inflammatory bowel disease (IBD) is debatable. We aim to compare NBI versus other endoscopic techniques in surveillance of IBD basing on current evidences.

METHODS

A systematic search of PubMed, Embase, and the Cochrane Library databases was conducted for relevant studies. To assess the detection efficacy, we estimated risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes. To assess the differentiation efficacy, we estimated sensitivity and specificity of NBI with reference to histology. All outcome variables were pooled using a random-effects model. Heterogeneity was tested by the Q statistic and I statistic.

RESULTS

A total of 10 studies involving 938 participants were included. Statistically significant differences were not found in the likelihood of detecting patients with dysplastic lesions [RR, 1.11; 95% confidence interval (CI), 0.83-1.48] nor in the likelihood of detecting dysplastic lesions by targeted biopsies (RR, 0.76; 95% CI, 0.51-1.12) between NBI and other techniques, and there was also no difference in the likelihood of detecting dysplastic subtypes. NBI required shorter procedural time compared with other techniques (MD, -10.23; 95% CI, -11.53 to -8.92). The sensitivity and specificity of NBI to differentiate neoplastic lesions from non-neoplastic lesions were 0.64 (95% CI, 0.50-0.77) and 0.74 (95% CI, 0.69-0.79), respectively, and the area under the curve (AUC) was 0.7626.

CONCLUSIONS

Although a shorter procedural time is needed, the clinical application of NBI for both dysplasia detection and neoplasia differentiation in IBD is not superior to other endoscopic techniques.

Clinical usefulness of magnifying colonoscopy for the diagnosis of ulcerative colitis-associated neoplasia

BACKGROUND AND AIM

The aim of this investigation was to evaluate the efficacy of Japanese magnifying colonoscopic classifications for ulcerative colitis-associated neoplasia (UCAN).

METHODS

We reviewed the colonoscopy records from 2011 to 2018 at our institutions and identified cases of endoscopically or surgically resected UCAN observed by magnifying narrow-band imaging (NBI) endoscopy and magnifying chromoendoscopy. Association between magnifying endoscopic classification and histopathological findings was investigated retrospectively. Japan NBI expert team (JNET) classification and pit pattern classification were applied.

RESULTS

There were 17 patients who had a diagnosis of UCAN. Tumors of types 2A, 2B and 3 by JNET classification correlated with the histopathological findings of low-grade dysplasia (LGD)/high-grade dysplasia (HGD), HGD, and massively submucosal invasive (mSM) carcinoma, respectively. Tumors of types III/IV, V_I low irregularity, and V_I high irregularity/V_N by pit pattern classification were correlated with the histopathological findings of LGD/HGD, HGD, and mSM carcinoma, respectively.

CONCLUSIONS

Japan NBI expert team classification and pit pattern classification may be predictive of the histological diagnosis and invasion depth of UCAN. This needs to be investigated prospectively in a large cohort or in a randomized clinical trial.

Diagnostic Accuracy of Endoscopic Trimodal Imaging and Chromoendoscopy for Lesion Characterization in Ulcerative Colitis

BACKGROUND

During surveillance colonoscopy of patients with long-standing ulcerative colitis [UC], a variety of dysplastic and non-dysplastic lesions are detected. The aim of this study was to address the diagnostic accuracy of endoscopic characterization of endoscopic trimodal imaging [ETMI] and chromoendoscopy [CE]. ETMI includes the combination of autofluorescence imaging [AFI], narrow band imaging [NBI] and white light endoscopy [WLE].

METHODS

This is a pre-specified additional analysis of a multi-centre, randomized controlled trial that compared AFI with CE for dysplasia detection in 210 patients with long-standing UC [FIND-UC trial]. In the AFI arm, endoscopists used the ETMI system to record AFI colour, Kudo pit pattern using NBI and WLE for lesion characterization. For AFI, purple colour and ambiguous colour combined with pit pattern type III-V on NBI was considered dysplastic. Kudo pit pattern was described in the CE arm. For pit pattern description using NBI and CE, type III-V was considered dysplastic. Histology was the reference standard.

RESULTS

In total, 52 dysplastic and 255 non-dysplastic lesions were detected. Overall sensitivity for real-time prediction of dysplasia was 76.9% (95% confidence interval [CI] 46.2-95.0) for ETMI, and 81.6% [95% CI 65.7-92.3] for CE. Overall negative predictive value [NPV] for ETMI was 96.9% [95% CI 92.0-98.8] and 94.7% [90.2-97.2] for CE.

CONCLUSIONS

Sensitivity for endoscopic differentiation of dysplastic lesions detected during surveillance of patients with long-standing UC seems limited using ETMI and CE. Future research is warranted as the high NPV indicates that these techniques are valuable for the exclusion of dysplastic lesions [NTR4062].

Colonic lesion characterization in inflammatory bowel disease: A systematic review and meta-analysis

AIM

To perform a systematic review and meta-analysis for the diagnostic accuracy of in vivo lesion characterization in colonic inflammatory bowel disease (IBD), using optical imaging techniques, including virtual chromoendoscopy (VCE), dye-based chromoendoscopy (DBC), magnification endoscopy and confocal laser endomicroscopy (CLE).

METHODS

We searched Medline, Embase and the Cochrane library. We performed a bivariate meta-analysis to calculate the pooled estimate sensitivities, specificities, positive and negative likelihood ratios (+LHR, -LHR), diagnostic odds ratios (DOR), and area under the SROC curve (AUSROC) for each technology group. A subgroup analysis was performed to investigate differences in real-time non-magnified Kudo pit patterns (with VCE and DBC) and real-time CLE.

RESULTS

We included 22 studies [1491 patients; 4674 polyps, of which 539 (11.5%) were neoplastic]. Real-time CLE had a pooled sensitivity of 91% (95%CI: 66%-98%), specificity of 97% (95%CI: 94%-98%), and an AUSROC of 0.98 (95%CI: 0.97-0.99). Magnification endoscopy had a pooled sensitivity of 90% (95%CI: 77%-96%) and specificity of 87% (95%CI: 81%-91%). VCE had a pooled sensitivity of 86% (95%CI: 62%-95%) and specificity of 87% (95%CI: 72%-95%). DBC had a pooled sensitivity of 67% (95%CI: 44%-84%) and specificity of 86% (95%CI: 72%-94%).

CONCLUSION

Real-time CLE is a highly accurate technology for differentiating neoplastic from non-neoplastic lesions in patients with colonic IBD. However, most CLE studies were performed by single expert users within tertiary centres, potentially confounding these results.