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Objectives: Computer‐aided characterization (CADx) may be used to implement optical biopsy strategies into colonoscopy practice; however, its impact on endoscopic diagnosis remains unknown. We aimed to evaluate the additional diagnostic value of CADx when used by endoscopists for assessing colorectal polyps. Methods: This was a single‐center, multicase, multireader, image‐reading study using randomly extracted images of pathologically confirmed polyps resected between July 2021 and January 2022. Approved CADx that could predict two‐tier classification (neoplastic or nonneoplastic) by analyzing narrow‐band images of the polyps was used to obtain a CADx diagnosis. Participating endoscopists determined if the polyps were neoplastic or not and noted their confidence level using a computer‐based, image‐reading test. The test was conducted twice with a 4‐week interval: the first test was conducted without CADx prediction and the second test with CADx prediction. Diagnostic performances for neoplasms were calculated using the pathological diagnosis as reference and performances with and without CADx prediction were compared. Results: Five hundred polyps were randomly extracted from 385 patients and diagnosed by 14 endoscopists (including seven experts). The sensitivity for neoplasia was significantly improved by referring to CADx (89.4% vs. 95.6%). CADx also had incremental effects on the negative predictive value (69.3% vs. 84.3%), overall accuracy (87.2% vs. 91.8%), and high‐confidence diagnosis rate (77.4% vs. 85.8%). However, there was no significant difference in specificity (80.1% vs. 78.9%). Conclusions: Computer‐aided characterization has added diagnostic value for differentiating colorectal neoplasms and may improve the high‐confidence diagnosis rate. [ABSTRACT FROM AUTHOR]

Objectives: Lymph node metastasis (LNM) prediction for T1 colorectal cancer (CRC) is critical for determining the need for surgery after endoscopic resection because LNM occurs in 10%. We aimed to develop a novel artificial intelligence (AI) system using whole slide images (WSIs) to predict LNM. Methods: We conducted a retrospective single center study. To train and test the AI model, we included LNM status‐confirmed T1 and T2 CRC between April 2001 and October 2021. These lesions were divided into two cohorts: training (T1 and T2) and testing (T1). WSIs were cropped into small patches and clustered by unsupervised K‐means. The percentage of patches belonging to each cluster was calculated from each WSI. Each cluster's percentage, sex, and tumor location were extracted and learned using the random forest algorithm. We calculated the areas under the receiver operating characteristic curves (AUCs) to identify the LNM and the rate of over‐surgery of the AI model and the guidelines. Results: The training cohort contained 217 T1 and 268 T2 CRCs, while 100 T1 cases (LNM‐positivity 15%) were the test cohort. The AUC of the AI system for the test cohort was 0.74 (95% confidence interval [CI] 0.58–0.86), and 0.52 (95% CI 0.50–0.55) using the guidelines criteria (P = 0.0028). This AI model could reduce the 21% of over‐surgery compared to the guidelines. Conclusion: We developed a pathologist‐independent predictive model for LNM in T1 CRC using WSI for determination of the need for surgery after endoscopic resection. Trial registration: UMIN Clinical Trials Registry (UMIN000046992, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000053590). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This article discusses the use of ultrahigh magnification endoscopy in the management of inflammatory bowel disease (IBD). The authors explain that while advanced endoscopic diagnostic techniques have been introduced into clinical practice, ultrahigh magnification endoscopy is not yet widely integrated. The article highlights the potential benefits of ultrahigh magnification endoscopy, such as the ability to observe new indicators and the potential for personalized and targeted approaches in IBD management. However, the authors note that further controlled studies are needed to clarify the impact of these new technologies in clinical decision-making. The article concludes by emphasizing the importance of bridging the gap between research and clinical practice to optimize the utilization of ultrahigh magnification endoscopy. [Extracted from the article]

Background: Colorectal cancer (CRC) can be classified into four consensus molecular subtypes (CMS) according to genomic aberrations and gene expression profiles. CMS is expected to be useful in predicting prognosis and selecting chemotherapy regimens. However, there are still no reports on the relationship between the morphology and CMS. Methods: This retrospective study included 55 subjects with T2 CRC undergoing surgical resection, of whom 30 had the depressed type and 25 the protruded type. In the classification of the CMS, we first defined cases with deficient mismatch repair as CMS1. And then, CMS2/3 and CMS4 were classified using an online classifier developed by Trinh et al. The staining intensity of CDX2, HTR2B, FRMD6, ZEB1, and KER and the percentage contents of CDX2, FRMD6, and KER are input into the classifier to obtain automatic output classifying the specimen as CMS2/3 or CMS4. Results: According to the results yielded by the online classifier, of the 30 depressed-type cases, 15 (50%) were classified as CMS2/3 and 15 (50%) as CMS4. Of the 25 protruded-type cases, 3 (12%) were classified as CMS1 and 22 (88%) as CMS2/3. All of the T2 CRCs classified as CMS4 were depressed CRCs. More malignant pathological findings such as lymphatic invasion were associated with the depressed rather than protruded T2 CRC cases. Conclusions: Depressed-type T2 CRC had a significant association with CMS4, showing more malignant pathological findings such as lymphatic invasion than the protruded-type, which could explain the reported association between CMS4 CRC and poor prognosis. [ABSTRACT FROM AUTHOR]

With the prevalence of endoscopic submucosal dissection and endoscopic full thickness resection, which enable complete resection of T1 colorectal cancer with a negative margin, the treatment strategy following endoscopic resection has become more important. The necessity of secondary surgical resection is determined on the basis of the risk of lymph node metastasis according to the histopathological findings of resected specimens because ~10% of T1 colorectal cancer cases have lymph node metastasis. The current Japanese treatment guidelines state four risk factors for lymph node metastasis: lymphovascular invasion, histological differentiation, depth of submucosal invasion, and tumor budding. These guidelines have succeeded in stratifying the low‐risk group for lymph node metastasis, in which endoscopic resection alone is acceptable for cure. On the other hand, there are some problems: there is variation in diagnosis methods and low interobserver agreement for each pathological factor and 90% of surgical resections are unnecessary, with lymph node metastasis negativity. To ensure patients with T1 colorectal cancer receive more appropriate treatment, these problems should be addressed. In this systematic review, we gave some suggestions to these practical issues of four pathological factors as predictors. [ABSTRACT FROM AUTHOR]

Ultra-magnifying endoscopy is used to conduct an optical biopsy that provides accurate pathological prediction based on a histologic-equivalent image.7 There are two methods of producing the cellular image: confocal laser endomicroscopy and endocytoscopy. This motivation prompted another revolution in magnifying endoscopy, resulting in the development of an ultra-magnification endoscopy system to acquire images at the cellular level I in vivo i . One of these goals is so-called "optical biopsy", which provides an accurate diagnosis comparable with the pathological diagnosis without the need for a biopsy. Magnifying endoscopy has become available worldwide and is now an essential diagnostic modality for gastrointestinal endoscopy; however, its development took several decades and was not easy. [Extracted from the article]

Magnifying endoscopy has become available worldwide and is now an essential diagnostic modality for gastrointestinal endoscopy; however, its development took several decades and was not easy. One of these goals is so-called "optical biopsy", which provides an accurate diagnosis comparable with the pathological diagnosis without the need for a biopsy. This motivation prompted another revolution in magnifying endoscopy, resulting in the development of an ultra-magnification endoscopy system to acquire images at the cellular level I in vivo i . Ultra-magnifying endoscopy is used to conduct an optical biopsy that provides accurate pathological prediction based on a histologic-equivalent image.7 There are two methods of producing the cellular image: confocal laser endomicroscopy and endocytoscopy. [Extracted from the article]

Background and Aim: Although patients report either improved or worsened halitosis after Helicobacter pylori eradication therapy, such complaints are subjective. Only a few studies have objectively evaluated reports of changes in halitosis after H. pylori eradication; thus, this study aimed to investigate these changes after a successful H. pylori eradication. Methods: Between February 2015 and October 2018, 56 347 patients visited the clinic. Informed consent for participation in this study was obtained from 164 patients scheduled to undergo upper gastrointestinal endoscopy due to halitosis. Of the 91 patients with H. pylori infection, the halitosis values were evaluated as Refres breath (RB) values using a Total Gas Detector™ System and compared before and after successful H. pylori eradication, as confirmed with urea breath testing. Results: Among the 91 patients treated, 77 patients were successfully eradicated of H. pylori and had their Refres values measured (21 men and 56 women; mean age, 64.2 ± 11.5 years, including 10 smokers); among these 77 patients, 27 showed RB values of > 60. Their RB values significantly improved from 73.5 Â (95% confidence interval [CI], 64.1–82.9) to 59.4 Â (95% CI, 50.0–68.8) (P = 0.038). Of the 30 patients who could be followed up for > 2 years after successful H. pylori eradication, 8 with an RB value ≥ 60 showed significant RB value improvements from 77.9 Â (95% CI, 59.4–96.4) to 30.1 Â (95% CI, 11.6–48.6) (P = 0.0016). Conclusions: Helicobacter pylori eradication therapy could improve halitosis, and such improvement could be maintained even 2 years after successful eradication. [ABSTRACT FROM AUTHOR]

Objectives: Ulcerative colitis‐associated neoplasias (UCAN) are often flat with an indistinct boundary from surrounding tissues, which makes differentiating UCAN from non‐neoplasias difficult. Pit pattern (PIT) has been reported as one of the most effective indicators to identify UCAN. However, regenerated mucosa is also often diagnosed as a neoplastic PIT. Endocytoscopy (EC) allows visualization of cell nuclei. The aim of this retrospective study was to demonstrate the diagnostic ability of combined EC irregularly‐formed nuclei with PIT (EC‐IN‐PIT) diagnosis to identify UCAN. Methods: This study involved patients with ulcerative colitis whose lesions were observed by EC. Each lesion was diagnosed by two independent expert endoscopists, using two types of diagnostic strategies: PIT alone and EC‐IN‐PIT. We evaluated and compared the diagnostic abilities of PIT alone and EC‐IN‐PIT. We also examined the difference in the diagnostic abilities of an EC‐IN‐PIT diagnosis according to endoscopic inflammation severity. Results: We analyzed 103 lesions from 62 patients; 23 lesions were UCAN and 80 were non‐neoplastic. EC‐IN‐PIT diagnosis had a significantly higher specificity and accuracy compared with PIT alone: 84% versus 58% (P < 0.001), and 88% versus 67% (P < 0.01), respectively. The specificity and accuracy were significantly higher for Mayo endoscopic score (MES) 0–1 than MES 2–3: 93% versus 68% (P < 0.001) and 95% versus 74% (P < 0.001), respectively. Conclusions: Our novel EC‐IN‐PIT strategy had a better diagnostic ability than PIT alone to predict UCAN from suspected and initially detected lesions using conventional colonoscopy. UMIN clinical trial (UMIN000040698). [ABSTRACT FROM AUTHOR]

Background: Lymph node metastasis (LNM) occurs in 20–25% of patients with T2 colorectal cancer (CRC). Identification of risk factors for LNM in T2 CRC may help identify patients who are at low risk and thereby potential candidates for endoscopic full-thickness resection. We examined risk factors for LNM in T2 CRC with the goal of establishing further criteria of the indications for endoscopic resection. Methods: MEDLINE, CENTRAL, and EMBASE were systematically searched from inception to November 2023. Studies that investigated the association between the presence of LNM and the clinical and pathological factors of T2 CRC were included. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Certainty of evidence (CoE) was assessed using the GRADE approach. Results: Fourteen studies (8349 patients) were included. Overall, the proportion of LNM was 22%. The meta-analysis revealed that the presence of lymphovascular invasion (OR, 5.5; 95% CI 3.7–8.3; high CoE), high-grade tumor budding (OR, 2.4; 95% CI 1.5–3.7; moderate CoE), poor differentiation (OR, 2.2; 95% CI 1.8–2.7; moderate CoE), and female sex (OR, 1.3; 95% CI 1.1–1.7; high CoE) were associated with LNM in T2 CRC. Lymphatic invasion (OR, 5.0; 95% CI 3.3–7.6) was a stronger predictor of LNM than vascular invasion (OR, 2.4; 95% CI 2.1–2.8). Conclusions: Lymphovascular invasion, high-grade tumor budding, poor differentiation, and female sex were risk factors for LNM in T2 CRC. Endoscopic resection of T2 CRC in patients with very low risk for LNM may become an alternative to conventional surgical resection. Trial registration: PROSPERO, CRD42022316545. [ABSTRACT FROM AUTHOR]

The global incidence and mortality rate of colorectal cancer remains high. Colonoscopy is regarded as the gold standard examination for detecting and eradicating neoplastic lesions. However, there are some uncertainties in colonoscopy practice that are related to limitations in human performance. First, approximately one‐fourth of colorectal neoplasms are missed on a single colonoscopy. Second, it is still difficult for non‐experts to perform adequately regarding optical biopsy. Third, recording of some quality indicators (e.g. cecal intubation, bowel preparation, and withdrawal speed) which are related to adenoma detection rate, is sometimes incomplete. With recent improvements in machine learning techniques and advances in computer performance, artificial intelligence‐assisted computer‐aided diagnosis is being increasingly utilized by endoscopists. In particular, the emergence of deep‐learning, data‐driven machine learning techniques have made the development of computer‐aided systems easier than that of conventional machine learning techniques, the former currently being considered the standard artificial intelligence engine of computer‐aided diagnosis by colonoscopy. To date, computer‐aided detection systems seem to have improved the rate of detection of neoplasms. Additionally, computer‐aided characterization systems may have the potential to improve diagnostic accuracy in real‐time clinical practice. Furthermore, some artificial intelligence‐assisted systems that aim to improve the quality of colonoscopy have been reported. The implementation of computer‐aided system clinical practice may provide additional benefits such as helping in educational poorly performing endoscopists and supporting real‐time clinical decision‐making. In this review, we have focused on computer‐aided diagnosis during colonoscopy reported by gastroenterologists and discussed its status, limitations, and future prospects. [ABSTRACT FROM AUTHOR]

Objectives: Recent studies have suggested the necessity of therapeutic intervention for patients with ulcerative colitis at high risk of clinical relapse with a Mayo endoscopic score (MES) of 1. The aim of this retrospective cohort study was to demonstrate the impact of intramucosal capillary network changes and crypt architecture abnormalities to stratify the risk of relapse in patients with an MES of 1. Methods: All included patients had an MES of ≤1 and confirmed sustained clinical remission between October 2016 and April 2019. We classified patients with an MES of 1 as "intramucosal capillary/crypt (ICC)‐active" or "ICC‐inactive" using endocytoscopic evaluation. We followed patients until October 2019 or until relapse; the main outcome measure was the difference in clinical relapse‐free rates between ICC‐active and ICC‐inactive patients with an MES of 1. Results: We included 224 patients and analyzed data for 218 (82 ICC‐active and 54 ICC‐active with an MES of 1 and 82 with an MES of 0). During follow‐up, among the patients with an MES of 1, 30.5% (95% confidence interval 20.8–41.6; 25/82) of the patients relapsed in the ICC‐active group and 5.6% (95% confidence interval 1.2–15.4; 3/54) of the patients relapsed in the ICC‐inactive group. The ICC‐inactive group had a significantly higher clinical relapse‐free rate compared with the ICC‐active group (P < 0.01). Conclusions: In vivo intramucosal capillary network and crypt architecture patterns stratified the risk of clinical relapse in patients with an MES of 1 (UMIN 000032580; UMIN 000036359). [ABSTRACT FROM AUTHOR]

Purpose: Although some studies have reported differences in clinicopathological features between left- and right-sided advanced colorectal cancer (CRC), there are few reports regarding early-stage disease. In this study, we aimed to compare the clinicopathological features of left- and right-sided T1 CRC. Methods: Subjects were 1142 cases with T1 CRC undergoing surgical or endoscopic resection between 2001 and 2018 at Showa University Northern Yokohama Hospital. Of these, 776 cases were left-sided (descending colon to rectum) and 366 cases were right-sided (cecum to transverse colon). We compared clinical (patients age, sex, tumor size, morphology, initial treatment) and pathological features (invasion depth, histological grade, lymphatic invasion, vascular invasion, tumor budding) including lymph node metastasis (LNM). Results: Left-sided T1 CRC showed significantly higher rates of LNM (left-sided 12.0% vs. right-sided 5.4%, P < 0.05) and lymphatic invasion (left-sided 32.7% vs. right-sided 23.2%, P < 0.05). Especially, the sigmoid colon and rectum showed higher rates of LNM (12.4% and 12.1%, respectively) than other locations. Patients with left-sided T1 CRC were younger than those with right-sided T1 CRC (64.9 years ±11.5 years vs. 68.7 ± 11.6 years, P < 0.05), as well as significantly lower rates of poorly differentiated carcinoma/mucinous carcinoma than right-sided T1 CRC (11.6% vs. 16.1%, P < 0.05). Conclusion: Left-sided T1 CRC, especially in the sigmoid colon and rectum, exhibited higher rates of LNM than right-sided T1 CRC, followed by higher rates of lymphatic invasion. These results suggest that tumor location should be considered in decisions regarding additional surgery after endoscopic resection. Trial registration: This study was registered with the University Hospital Medical Network Clinical Trials Registry (UMIN 000032733). [ABSTRACT FROM AUTHOR]

Purpose: Screening programs using fecal occult blood testing help reduce mortality from colorectal cancer (CRC). Colonoscopy and colonoscopy combined with fecal occult blood testing are considered alternatives with higher sensitivity than fecal tests; however, to our knowledge, randomized controlled trials (RCTs) providing such evidence have not been reported. Therefore, this study aimed to compare screening using the fecal immunochemical test (FIT) combined with colonoscopy and FIT alone to evaluate the efficacy of colonoscopy screening in reducing CRC mortality. Methods: This multicenter, prospective, randomized, controlled study included average-risk individuals for CRC living in the study areas and aged 40–74 years. The exclusion criteria were history of CRC, hereditary non-polyposis CRC, familial adenomatous polyposis, inflammatory bowel diseases, history of cancer other than CRC within the past 5 years, and not expected to survive from comorbid illness. The intervention group underwent one-time colonoscopy and annual FIT, while the control group underwent annual FIT. The primary endpoint was mortality from CRC, while the secondary endpoints were cumulative incidence of invasive CRC, advanced CRC (invasion into the muscle layer or deeper), invasive cancer and screening sensitivities and specificities of invasive CRC, whole CRC, advanced neoplasia, and prevalence of adverse events. The intervention and control groups comprised 4876 and 4875 participants, respectively. Conclusion: This explanatory RCT evaluated the efficacy of colonoscopy screening by valid statistical inference based on randomization. Data on adverse events from this kind of screening are necessary when considering implementation of future screening programs. Trial registration: UMIN Clinical Trials Registry, number UMIN000001980. [ABSTRACT FROM AUTHOR]

Endoscopic full-thickness resection (eFTR) for colorectal lesions has recently become a more widely performed procedure [[1], [3]] Typical indications for eFTR are: (1) non-lifting lesion because of severe fibrosis or deep submucosal invasion; (2) repeat treatment because of previous incomplete resection or residual cancer after endoscopic resection; and (3) submucosal tumor. Lesions with these characteristics are difficult to resect by conventional endoscopic mucosal resection or endoscopic submucosal dissection techniques. Endoscopic full-thickness resection for complex colorectal lesions - what's the next step?. [Extracted from the article]

Background and Aim: Application of artificial intelligence in medicine is now attracting substantial attention. In the field of gastrointestinal endoscopy, computer‐aided diagnosis (CAD) for colonoscopy is the most investigated area, although it is still in the preclinical phase. Because colonoscopy is carried out by humans, it is inherently an imperfect procedure. CAD assistance is expected to improve its quality regarding automated polyp detection and characterization (i.e. predicting the polyp's pathology). It could help prevent endoscopists from missing polyps as well as provide a precise optical diagnosis for those detected. Ultimately, these functions that CAD provides could produce a higher adenoma detection rate and reduce the cost of polypectomy for hyperplastic polyps. Methods and Results: Currently, research on automated polyp detection has been limited to experimental assessments using an algorithm based on ex vivo videos or static images. Performance for clinical use was reported to have >90% sensitivity with acceptable specificity. In contrast, research on automated polyp characterization seems to surpass that for polyp detection. Prospective studies of in vivo use of artificial intelligence technologies have been reported by several groups, some of which showed a >90% negative predictive value for differentiating diminutive (≤5 mm) rectosigmoid adenomas, which exceeded the threshold for optical biopsy. Conclusion: We introduce the potential of using CAD for colonoscopy and describe the most recent conditions for regulatory approval for artificial intelligence‐assisted medical devices. [ABSTRACT FROM AUTHOR]

With recent breakthroughs in artificial intelligence, computer‐aided diagnosis (CAD) for upper gastrointestinal endoscopy is gaining increasing attention. Main research focuses in this field include automated identification of dysplasia in Barrett's esophagus and detection of early gastric cancers. By helping endoscopists avoid missing and mischaracterizing neoplastic change in both the esophagus and the stomach, these technologies potentially contribute to solving current limitations of gastroscopy. Currently, optical diagnosis of early‐stage dysplasia related to Barrett's esophagus can be precisely achieved only by endoscopists proficient in advanced endoscopic imaging, and the false‐negative rate for detecting gastric cancer is approximately 10%. Ideally, these novel technologies should work during real‐time gastroscopy to provide on‐site decision support for endoscopists regardless of their skill; however, previous studies of these topics remain ex vivo and experimental in design. Therefore, the feasibility, effectiveness, and safety of CAD for upper gastrointestinal endoscopy in clinical practice remain unknown, although a considerable number of pilot studies have been conducted by both engineers and medical doctors with excellent results. This review summarizes current publications relating to CAD for upper gastrointestinal endoscopy from the perspective of endoscopists and aims to indicate what is required for future research and implementation in clinical practice. [ABSTRACT FROM AUTHOR]

With recent advances in endoscopic treatment, many T1 colorectal carcinomas (CRCs) are resected endoscopically with a negative margin. However, some lesions exhibit skip lymphovascular invasion (SLVI), which is defined as the discontinuous foci of the tumor cells within the colon wall. The aim of the present study was to reveal the clinicopathological features of T1 CRCs with SLVI and validate the Japanese guidelines regarding SLVI. A total of 741 patients with T1 CRCs that were resected surgically between April 2001 and October 2016 in our hospital were divided into two groups: With SLVI and without SLVI. Clinicopathological features compared between the two groups were patient's gender, age, tumor size, location, morphology, lymphovascular invasion, tumor differentiation, tumor budding and lymph node metastasis. The incidence of T1 CRCs with SLVI was 0.9% (7/741). All cases with SLVI were found in the sigmoid colon or rectum. T1 CRCs with SLVI showed significantly higher rates of lymphovascular invasion than those without SLVI (P<0.01). In conclusion, lymphovascular invasion was a significant risk factor for SLVI in T1 CRCs, and for which surgical colectomy was necessary. The Japanese guidelines are appropriate regarding SLVI. Registered in the University Hospital Medical Network Clinical Trials Registry (UMIN000027097). [ABSTRACT FROM AUTHOR]

Background: Computer-aided diagnosis (CAD) for colonoscopy may help endoscopists distinguish neoplastic polyps (adenomas) requiring resection from nonneoplastic polyps not requiring resection, potentially reducing cost.Objective: To evaluate the performance of real-time CAD with endocytoscopes (×520 ultramagnifying colonoscopes providing microvascular and cellular visualization of colorectal polyps after application of the narrow-band imaging [NBI] and methylene blue staining modes, respectively).Design: Single-group, open-label, prospective study. (UMIN [University hospital Medical Information Network] Clinical Trial Registry: UMIN000027360).Setting: University hospital.Participants: 791 consecutive patients undergoing colonoscopy and 23 endoscopists.Intervention: Real-time use of CAD during colonoscopy.Measurements: CAD-predicted pathology (neoplastic or nonneoplastic) of detected diminutive polyps (≤5 mm) on the basis of real-time outputs compared with pathologic diagnosis of the resected specimen (gold standard). The primary end point was whether CAD with the stained mode produced a negative predictive value (NPV) of 90% or greater for identifying diminutive rectosigmoid adenomas, the threshold required to "diagnose-and-leave" nonneoplastic polyps. Best- and worst-case scenarios assumed that polyps lacking either CAD diagnosis or pathology were true- or false-positive or true- or false-negative, respectively.Results: Overall, 466 diminutive (including 250 rectosigmoid) polyps from 325 patients were assessed by CAD, with a pathologic prediction rate of 98.1% (457 of 466). The NPVs of CAD for diminutive rectosigmoid adenomas were 96.4% (95% CI, 91.8% to 98.8%) (best-case scenario) and 93.7% (CI, 88.3% to 97.1%) (worst-case scenario) with stained mode and 96.5% (CI, 92.1% to 98.9%) (best-case scenario) and 95.2% (CI, 90.3% to 98.0%) (worst-case scenario) with NBI.Limitation: Two thirds of the colonoscopies were conducted by experts who had each experienced more than 200 endocytoscopies; 186 polyps not assessed by CAD were excluded.Conclusion: Real-time CAD can achieve the performance level required for a diagnose-and-leave strategy for diminutive, nonneoplastic rectosigmoid polyps.Primary Funding Source: Japan Society for the Promotion of Science. [ABSTRACT FROM AUTHOR]

Purpose: The recurrence of T1 colorectal cancers is relatively rare, and the prognostic factors still remain obscure. This study aimed to clarify the risk factors for recurrence in patients with T1 colorectal cancers treated by endoscopic resection (ER) alone or surgical resection (SR) with lymph node dissection, respectively.Methods: We reviewed 930 patients with resected T1 colorectal cancers (mean follow-up, 52.3 months). Patients were divided into two groups: those who underwent ER alone (298 cases), and those who underwent initial or additional SR with lymph node dissection (632 cases). Group differences in recurrence-free survival were evaluated using the Kaplan-Meier method and log-rank test. Associations between recurrence and clinicopathological features were evaluated in Cox regression analyses; hazard ratios (HRs) were calculated for the total population and each group.Results: Recurrence occurred in four cases (1.34%) in the ER group and six cases (0.95%) in the SR group (p = 0.32). Endoscopic resection, rectal location, and poor or mucinous (Por/Muc) differentiation were prognostic factors for recurrence in the total population. Por/Muc differentiation was prognostic factor in both groups. Female sex, depressed-type morphology, and lymphatic invasion were also prognostic factors in the ER group, but not in the SR group.Conclusions: Endoscopic resection, rectal location, and Por/Muc differentiation are prognostic factors in the total population. For patients who undergo ER alone, female sex, depressed-type morphology, and lymphatic invasion are also risk factors for recurrence. For such patients, regional en-bloc surgery with lymph node dissection could reduce the risk of recurrence. [ABSTRACT FROM AUTHOR]

This AI-assisted detection was of particular value because the lesion was found to be a submucosally invasive colorectal cancer. A 64-year-old man underwent surveillance colonoscopy with a computer-aided detection (CADe) system (EndoBRAIN-EYE; Cybernet Systems, Tokyo, Japan) [1]. Shin-ei Kudo, Masashi Misawa, and Yuichi Mori have received speaking honoraria from Olympus Corporation (Tokyo, Japan) and have ownership interest in the products of Cybernet Systems (Tokyo, Japan). [Extracted from the article]

Background/Aim: Previous reports stated that pedunculated T1 colorectal carcinomas with ‘head invasion’ showed almost no nodal metastasis, requiring endoscopic treatment alone. However, clinically, some lesions develop nodal metastasis. We aimed to validate the necessity of distinguishing between ‘pedunculated’ and ‘non-pedunculated’ lesions, and also between ‘head’ and ‘stalk’ invasions. Methods: Initial or additional surgery with lymph node dissection was performed in 76 pedunculated and 594 non-pedunculated cases. Among pedunculated lesions, the baseline was defined as the junction line between normal and neoplastic epithelium (Haggitt’s level 2). The degree of invasion was classified as ‘head invasion’ (above the baseline) or ‘stalk invasion’ (beyond the baseline). Clinicopathological factors were analyzed with respect to nodal metastasis. Results: Nine of 76 (11.8%) pedunculated cases and 52/594 (8.8%) non-pedunculated cases developed nodal metastasis (p = 0.40). No significant differences were found in the rate of nodal metastasis between ‘head invasion’ (4/30, 13.3%) and ‘stalk invasion’ (5/46, 10.9%). All the 4 cases with ‘head invasion’ had at least one pathological factor. Conclusions: ‘Head invasion’ was not a metastasis-free condition. Even for pedunculated T1 cancers with ‘head invasion’, additional surgery with lymph node dissection should be considered if these have pathological risk factors. [ABSTRACT FROM AUTHOR]

Most guidelines for curative criteria after endoscopic resection of T1 colorectal cancer (CRC), such as those of the United States, Europe, and Asia, including Japan, include tumor differentiation as a risk factor for lymph node metastasis (LNM).1 Surgical resection with lymph node dissection is recommended if poorly differentiated adenocarcinoma, signet-ring cell carcinoma, or mucinous carcinoma is diagnosed on histological examination. 1).3,4 There are also some Japanese reports in which it is unclear whether the differentiation was diagnosed as predominant or highest grade.2 The risk of LNM depends on how histological differentiation is classified. [Extracted from the article]

Background and Aim Recent advances in endoscopic technology have allowed many T1 colorectal carcinomas to be resected endoscopically with negative margins. However, the criteria for curative endoscopic resection remain unclear. We aimed to identify risk factors for nodal metastasis in T1 carcinoma patients and hence establish the indication for additional surgery with lymph node dissection. Methods Initial or additional surgery with nodal dissection was performed in 653 T1 carcinoma cases. Clinicopathological factors were retrospectively analyzed with respect to nodal metastasis. The status of the muscularis mucosae (MM grade) was defined as grade 1 (maintenance) or grade 2 (fragmentation or disappearance). The lesions were then stratified based on the risk of nodal metastasis. Results Muscularis mucosae grade was associated with nodal metastasis ( P = 0.026), and no patients with MM grade 1 lesions had nodal metastasis. Significant risk factors for nodal metastasis in patients with MM grade 2 lesions were attribution of women ( P = 0.006), lymphovascular infiltration ( P < 0.001), tumor budding ( P = 0.045), and poorly differentiated adenocarcinoma or mucinous carcinoma ( P = 0.007). Nodal metastasis occurred in 1.06% of lesions without any of these pathological factors, but in 10.3% and 20.1% of lesions with at least one factor in male and female patients, respectively. There was good inter-observer agreement for MM grade evaluation, with a kappa value of 0.67. Conclusions Stratification using MM grade, pathological factors, and patient sex provided more appropriate indication for additional surgery with lymph node dissection after endoscopic treatment for T1 colorectal carcinomas. [ABSTRACT FROM AUTHOR]

Sessile serrated adenomas/polyps (SSA/P) are considered to be precursors of colorectal cancers. They therefore need to be distinguished from hyperplastic polyps, and should be treated similarly to adenomas. Various endoscopic classifications for discriminating SSA/P have recently been proposed and validated, including the 'Type II-O' pit pattern in magnifying chromoendoscopy and the 'varicose microvascular vessel' in narrow-band imaging. However, there is currently no diagnostic consensus on the endoscopic appearance of SSA/P. Endocytoscopy (EC) is an emerging modality with diagnostic potential for SSA/P. EC is a type of a contact light microscopy, which allows in vivo visualization of cells and nuclei facilitating precise, real-time pathological prediction. SSA/P show oval gland lumens with small round nuclei in EC, indirectly reflecting the pathological features. EC has shown a sensitivity of 83.3% and a specificity of 97.8% for the diagnosis of SSA/P. EC is also a promising tool for the diagnosis of SSA/P with cytological dysplasia because of its ability to detect morphological changes in nuclei, which is the most important factor determining the presence of dysplasia in the lesion. However, clinical data validating the usefulness of EC are lacking, and further studies are required. [ABSTRACT FROM AUTHOR]

Purpose: Submucosal invasion depth (SID) in colorectal carcinoma (CRC) is an important factor in estimating risk of lymph node metastasis, but can be difficult to measure, leading to inadequate or over-extensive treatment. Here, we aimed to clarify the practical aspects of measuring SID in T1 CRC. Methods: We investigated 568 T1 CRCs that were resected surgically at our hospital from April 2001 to December 2013, and relationships between SID and clinicopathological factors, including the means of measurement, lesion morphology, and lymph node metastasis. Results: Of these 568 lesions, the SID was ≥1000 μm in 508 lesions. SIDs for lesions measured from the surface layer were all ≥1000 μm. Although lesions with SIDs ≥1000 μm were associated with significantly higher levels of unfavorable histologic types and lymphovascular infiltration than shallower lesions, a depth of ≥1000 μm was not a significant risk factor for lymph node metastasis (LNM) (6.7 vs. 9.8 %; P = 0.64), and no lesions for which the sole pathological factor was SID ≥1000 μm had lymph node metastasis. Protruded lesions showed deeper SIDs than other types. Conclusions: Although we found several problems of measuring SID in this study, we also found, surprisingly, that SID is not a risk factor for lymph node metastasis, and its measurement is not needed to estimate the risk of lymph node metastasis. [ABSTRACT FROM AUTHOR]

Background and Aim Endocytoscopy (EC) is a next-generation endoscopic technique that enables diagnostic imaging at 450× magnification. In the present study, we retrospectively evaluated the diagnostic performance of EC and magnifying chromoendoscopy (MCE) for diagnosing the invasion depth of colorectal tumors. Methods We investigated 330 lesions with a ≥10-mm tumor diameter that could be diagnosed by both MCE and EC. The lesions were classified according to morphological type as follows: laterally spreading type-granular (LST-G), laterally spreading type-non-granular (LST-NG), protruding, or depressed. After all lesions had been classified by both pit pattern and EC, qualitative and quantitative (invasion depth) diagnoses were made. The diagnostic accuracy was then compared between pit pattern classification and EC classification. Results Diagnostic accuracy of EC classification was significantly higher for LST-NG lesions (90.5%) than for protruding lesions (80.6%) ( P < 0.05). Diagnostic accuracy for LST-NG lesions was significantly higher with EC classification (90.5%) than with pit pattern classification (79.3%) ( P < 0.001). Comparison of the diagnostic performance of EC3a findings using EC classification between LST-NG and protruding lesions revealed a sensitivity of 92.9% versus 11.3% ( P < 0.001), positive predictive value of 78.0% versus 27.3% ( P < 0.001), negative predictive value of 95.5% versus 56.1% ( P < 0.001), and diagnostic accuracy of 87.9% versus 51.2% ( P < 0.001), respectively. Conclusion EC is a very useful method for evaluating the invasion depth of LST-NG lesions. [ABSTRACT FROM AUTHOR]

AI-based polyp detection systems are used during colonoscopy to increase lesion detection [3]. 1 The artificial intelligence-based detection system identified dysplasia. a First lesion. b Second lesion. [Extracted from the article]

Background and study aims: Conventional endoscopic resection (CER) includes polypectomy and endoscopic mucosal resection. The most common complications related to these techniques are post procedure bleeding and perforation. The aim of this study was to evaluate the outcomes of CER for colorectal neoplasms ≧20 mm and to clarify predictive factors for complications. Patients and methods: We conducted a multicenter prospective study at 18 specialized institutes. From October 2007 to December 2010, 1,029 CERs were performed at participating institutes. We collected the data prospectively and analyzed gender, age, tumor size, gross appearance, mode of resection, etc. Results: The mean size of polyps resected was 26.4 ± 8.6 mm (range 20-120 mm). The final pathology was Vienna classification category 1 or 2 in 24, category 3 in 502, and category 4 or 5 in 503 lesions. Post procedure bleeding and intra procedure perforation occurred, respectively, in 16 (1.6 %) and 8 cases (0.78 %). The overall complication rate was 2.3 %. Risk factors for bleeding in multivariate analysis were only patients under 60 years of age. Risk factors for perforation in multivariate analysis were en bloc resection and Vienna classification category 4-5. The difference of complication rate was not statistically significant regarding gender, size, tumor location, gross appearance, treatment method, and kind of insufflation. Conclusion: CER is a safe, efficient, and effective minimally invasive therapy for large colorectal lesions. However, care should be taken for post procedure bleeding in patients under 60 years of age and for perforation in cases of Vienna classification category 4-5 or when an en bloc resection is tried. [ABSTRACT FROM AUTHOR]

Optical biopsy techniques were recently introduced to luminal gastrointestinal endoscopy. These include confocal laser endomicroscopy, spectroscopic imaging techniques and endocytoscopy. Optical biopsy techniques allow on demand in vivo histology during ongoing endoscopy, thereby potentially accelerating clinical diagnosis and specific therapy. In the present review, we focus on endocytoscopy as one of the rapidly emerging optical biopsy techniques. We provide technical details of currently available endocytoscopy systems and give tips on their use in clinical practice. We also summarize applications of endocytoscopy for colorectal pathologies. [ABSTRACT FROM AUTHOR]

LINKED CONTENT This article is linked to Jangi et al papers. To view these articles, visit https://doi.org/10.1111/apt.16026 and https://doi.org/10.1111/apt.16316 [ABSTRACT FROM AUTHOR]

Background and Aim Endocytoscopy ( EC) at ultra-high magnification enables in vivo visualization of cellular atypia of gastrointestinal mucosae. Clear images are essential for precise diagnosis by EC. The aim of the present study was to evaluate the optimal staining method for EC in the colon. Methods Thirty prospectively enrolled patients were allocated 1:1:1 to three distinct staining methods: 0.05% crystal violet ( CV) alone, 1% methylene blue ( MB) alone, or CV + MB ( CM double). Normal rectal mucosae were stained with each dye and videos of EC images were recorded. Visibility of nuclei and gland formation after staining were evaluated as 'recognizable' or 'not recognizable'. Time for each parameter to become 'recognizable' was measured, and the average times for the three staining regimens were compared. Results MB alone and CM double staining resulted in 'recognizable' (102 ± 27 vs 89 ± 22 s, P = 0.263) nuclei within comparable periods of time, whereas CV alone was unable to identify nuclei. Gland formation became 'recognizable' sooner after CM double staining than after MB alone (61 ± 16 vs 108 ± 24 s, P < 0.001). Conclusions Double staining with CV and MB, which rapidly provided recognizable images of both nuclei and gland formation, is an appropriate staining regimen for colonic EC. [ABSTRACT FROM AUTHOR]

Background and Aim Pit pattern ( PIT) diagnosis with magnifying chromoendoscopy is effective diagnostic method for predicting a massively invasive submucosal colorectal cancer ( SMm) which has possibility of metastasis, whereas endocytoscopy ( EC) is recently reported to provide excellent diagnostic ability by enabling in vivo cellular visualization. The aim was to assess the additional diagnostic value of EC to PIT for diagnosing colorectal lesions. Methods We conducted a retrospective comparative analysis using a prospectively recorded database in a referral hospital. The subjects were 538 patients who were detected of a colorectal lesion with use of a magnifying colonoscope with EC capability. Each detected lesion was initially diagnosed by PIT findings followed by EC diagnosis by the on-site endoscopist. The diagnostic abilities in predicting neoplastic change and SMm were compared between PIT and PIT plus EC. Results Overall, 514 lesions from 455 patients were available for analysis. Of them, there were 58 non-neoplastic lesions, 352 adenomas, 15 slightly invasive submucosal cancers, and 89 SMm. The diagnostic abilities of predicting neoplastic change were comparable between PIT and PIT plus EC: sensitivity was 97.8% versus 97.4%, specificity was 91.4% versus 89.7%, and accuracy was 97.1% versus 96.5%. Regarding those of predicting SMm, PIT plus EC showed additional specificity and accuracy to PIT: specificity was 99.1% versus 97.6% ( P = 0.041), and accuracy was 96.3% versus 93.8% ( P = 0.004). Conclusions Though PIT has feasible diagnostic ability for predicting both neoplastic change and SMm, EC provides additional diagnostic value to PIT diagnosis for predicting SMm. [ABSTRACT FROM AUTHOR]

Background: The number of patients suffering from colorectal cancer is increasing. According to Japanese guidelines, lesions with a submucosal invasive depth >1,000 μm should be treated with radical proctocolectomy. We propose and evaluate a new clinical classification for pit patterns that uses endoscopy to assess lesion depth for determination of the appropriate therapeutic approach for early colorectal cancers and adenomas. Methods: Endoscopic images of colorectal adenomas and early cancer cases with type V pit pattern, resected surgically or endoscopically from April 2002 to April 2007 at Showa University Yokohama Northern Hospital, were utilized for analysis. Each image was retrospectively analyzed for (A) pit narrowness, (B) irregular pit margins, and (C) indistinct stromal staining. Sensitivity, specificity, and predictive value were evaluated as major outcomes, using pathological results as the standard. Result: In total, 186 cases were assessed. With all features considered (A, B, and C), the sensitivity, specificity, and positive and negative predictive values were 47.8%, 86.3%, 66.0%, and 74.2%, respectively. When limited to two features (A and B), these values were 75.3%, 81.2%, 70.2%, and 84.8%, respectively. Conclusion: Our results suggest that the established criteria can, to a certain degree, distinguish between high and low irregularity in colorectal lesions with V pit pattern indicating submucosal cancer infiltration of more or less than 1,000 μm with the clinical consequence of surgery versus endoscopic mucosal resection/endoscopic mucosal dissection. [ABSTRACT FROM AUTHOR]

Background: Magnifying colonoscopy with NBI has been shown to be useful for the differential diagnosis of tumors. However, the relationship between findings on NBI magnification and the microvessel architecture of colorectal lesions remains to be clarified.Aims: The aim of this study was to clarify the correlation between NBI findings and the microvascular architecture of colorectal lesions according to the depth of microvessels from the mucosal surface.Methods: A total of 22 colorectal lesions (11 tubular adenomas and 11 hyperplasia) obtained from 22 patients were studied. These lesions were analyzed microscopically on tissue specimens immunostained with CD34. Three-dimensional images were reconstructed from serial sections of tubular adenomas, hyperplasia, and normal mucosa.Results: Three-dimensional reconstructed images of tubular adenoma and normal mucosa to a depth of less than 150 μm from the mucosal surface showed similar structures to images obtained by NBI magnification. Microvessel diameter was significantly larger in tubular adenoma than in normal mucosa (P = 0.002) and hyperplasia (P = 0.034), and microvessel area was significantly larger in tubular adenoma than in normal mucosa (P < 0.001) and hyperplasia (P < 0.001) only in the superficial mucosal layer (to a depth of less than 150 μm).Conclusions: TA was characterized by thicker microvessels and higher volume of microvessels than NM and HP. Compared with white light, NBI can more accurately depict the characteristics of microvessels because it uses light with short wavelengths, thereby contributing to high diagnostic capability. [ABSTRACT FROM AUTHOR]

Magnifying narrow band imaging (NBI) has enabled to observe the vascular pattern of colorectal lesions. Their broad findings have been divided into six groups according to endoscopical vascular features: normal, faint, network, dense, irregular and sparse. Most hyperplastic polyps show a faint pattern. The vascular patterns of adenomas are mainly network or dense ones. The predominant vascular patterns of cancer were irregular and sparse. Indeed, irregular pattern has found to be characteristic for protruded or flat-elevated cancer, whereas sparse pattern unique for depressed cancer. Through NBI, neoplastic lesions could be differentiated from those non-neoplastic with sensitivity of 83.5%, specificity of 98.7% and accuracy of 98.2%. It was able to distinguish between massively submucosal invasive cancers and slightly submucosal invasive cancers by using the vascular pattern with 91.0% sensitivity and 79.4% specificity. The overall accuracy was 88.3%. NBI system has showed to be a valuable technique for distinguishing neoplastic from non-neoplastic lesions, as well as massively from slightly submucosal invasive cancer. Therefore, vascular pattern analysis might be a promising tool for determining treatment selection, whether endoscopical or surgically. [ABSTRACT FROM AUTHOR]

In colorectal cancers, although flat and depressed-type lesions are found by regular endoscopic view, magnification and pit-pattern observation are vital parts of the precise diagnosis of the lesion. The depressed-type lesions appear to have a prominent tendency to show malignant characteristics, and the recognition and timely treatment of such lesions is important for improving the morbidity and mortality of colorectal cancer. Chromoscopy is mandatory for an accurate diagnosis of these lesions. The pit-pattern classification correlates well with actual histological findings and can provide important additional information prior to endoscopic treatment of the lesion. [ABSTRACT FROM AUTHOR]

Abstract The present review describes the changes in views about the early forms of colorectal cancers. In 1985, a concept of ‘flat adenoma’ was born in Japan. At around the same time, depressed type early colorectal cancers started to be reported by Japanese colonoscopists. Neither flat adenomas nor depressed lesions have been frequently reported in Western countries, but increasing numbers of such cases are now described. The problem is that flat adenomas and depressed lesions seem to have been confused by many researchers. The biological aggressiveness of these lesions is quite different. The rate of submucosal invasion is very high in depressed lesions, but fairly low in small flat adenomas. Some adenomas may even look depressed at first, but such lesions should not be mistaken for truly depressed lesions. Ignorance or resistance to the concept may inhibit the detection of flat or depressed lesions. Differences of diagnostic criteria between Japanese and Western pathologists may influence the apparent frequency of mucosal cancers, but not that of invasive carcinomas. Many small adenomas do not grow if followed, but depressed lesions grow rapidly and invade the deeper layers and, as a result, may look elevated as a whole. Many cases in previously published papers suggest that small depressed carcinomas of the large intestine may develop without a precursory stage of an adenomatous polyp. At least two carcinogenic pathways, one through adenomatous polyps and one de novo, should be recognized. In addition, the importance of small depressed cancers should be emphasized. [ABSTRACT FROM AUTHOR]

Background: The clinicopathological features and prognosis of primary small bowel adenocarcinoma (PSBA), excluding duodenal cancer, remain undetermined due to its rarity in Japan. Methods: We analyzed 354 patients with 358 PSBAs, between January 2008 and December 2017, at 44 institutions affiliated with the Japanese Society for Cancer of the Colon and Rectum. Results: The median age was 67 years (218 males, 61.6%). The average tumor size was 49.9 (7–100) mm. PSBA sites consisted of jejunum (66.2%) and ileum (30.4%). A total of 219 patients (61.9%) underwent diagnostic small bowel endoscopy, including single-balloon endoscopy, double-balloon endoscopy, and capsule endoscopy before treatment. Nineteen patients (5.4%) had Lynch syndrome, and 272 patients (76.8%) had symptoms at the initial diagnosis. The rates for stages 0, I, II, III, and IV were 5.4%, 2.5%, 27.1%, 26.0%, and 35.6%, respectively. The 5-year overall survival rates at each stage were 92.3%, 60.0%, 75.9%, 61.4%, and 25.5%, respectively, and the 5-year disease-specific survival (DSS) rates were 100%, 75.0%, 84.1%, 59.3%, and 25.6%, respectively. Patients with the PSBA located in the jejunum, with symptoms at the initial diagnosis or advanced clinical stage had a worse prognosis. However, multivariate analysis using Cox-hazard model revealed that clinical stage was the only significant predictor of DSS for patients with PSBA. Conclusions: Of the patients with PSBA, 76.8% had symptoms at the initial diagnosis, which were often detected at an advanced stage. Detection during the early stages of PSBA is important to ensure a good prognosis. [ABSTRACT FROM AUTHOR]

Background and Aim: Computer‐aided detection (CADe) systems can efficiently detect polyps during colonoscopy. However, false‐positive (FP) activation is a major limitation of CADe. We aimed to compare the rate and causes of FP using CADe before and after an update designed to reduce FP. Methods: We analyzed CADe‐assisted colonoscopy videos recorded between July 2022 and October 2022. The number and causes of FPs and excessive time spent by the endoscopist on FP (ET) were compared pre‐ and post‐update using 1:1 propensity score matching. Results: During the study period, 191 colonoscopy videos (94 and 97 in the pre‐ and post‐update groups, respectively) were recorded. Propensity score matching resulted in 146 videos (73 in each group). The mean number of FPs and median ET per colonoscopy were significantly lower in the post‐update group than those in the pre‐update group (4.2 ± 3.7 vs 18.1 ± 11.1; P < 0.001 and 0 vs 16 s; P < 0.001, respectively). Mucosal tags, bubbles, and folds had the strongest association with decreased FP post‐update (pre‐update vs post‐update: 4.3 ± 3.6 vs 0.4 ± 0.8, 0.32 ± 0.70 vs 0.04 ± 0.20, and 8.6 ± 6.7 vs 1.6 ± 1.7, respectively). There was no significant decrease in the true positive rate (post‐update vs pre‐update: 95.0% vs 99.2%; P = 0.09) or the adenoma detection rate (post‐update vs pre‐update: 52.1% vs 49.3%; P = 0.87). Conclusions: The updated CADe can reduce FP without impairing polyp detection. A reduction in FP may help relieve the burden on endoscopists. [ABSTRACT FROM AUTHOR]

The European Society of Gastrointestinal Endoscopy does not recommend self-expanding metal stent (SEMS) placement as a bridge to surgery (BTS) for malignant colorectal obstruction (MCRO). However, no universally accepted consensus has been determined. The present study aimed to evaluate the short- and long-term outcomes of SEMS placement vs. emergency surgery (ES) for MCRO. Surgical resection of colorectal cancer was performed in 3,840 patients between April 2001 and June 2016. Of these, 93 patients had MCRO requiring emergency decompression. Only patients in whom the colorectal lesion was ultimately resected were included; thus, the present study included 62 patients treated with MCRO via SEMS placement as a BTS (n=25) or via ES (n=37). The rates of laparoscopic surgery, primary anastomosis, stoma formation, lymph node dissection, adverse events, 30-day mortality and disease-free survival were evaluated. The clinical success rate of SEMS placement was 92.0% (23/25). Compared with the ES group, the SEMS group had higher rates of laparoscopic surgery (68.0 vs. 2.7%; P<0.001) and primary anastomosis (88.0 vs. 51.4%; P=0.003), a greater number of dissected lymph nodes (30 vs. 18; P=0.001), and lower incidences of stoma formation (24.0 vs. 67.6%; P=0.002) and overall adverse events (24.0 vs. 62.2%; P=0.004). The 30-day mortality and disease-free survival of the SEMS group were not significantly different to that of the ES group (0 vs. 2.7%; P=1.000; log-rank test; P=0.10). In conclusion, as long as adverse events such as perforation are minimized, SEMS placement as a BTS could be a first treatment option for MCRO. The present study is registered in the University Hospital Medical Network Clinical Trials Registry (UMIN R000034868). [ABSTRACT FROM AUTHOR]

The article presents case studies of 42-year-old man and 42-year-old woman who were diagnosed with colitis-associated neoplasia (CAN) which thereby was observed with endocytoscopy. It presents information on observation of enlarged nuclei and irregular lumens using methylene blue staining in the 42-year-old woman. It presents information on use of artificial intelligence technology for diagnosis of CAN. It states that the 42-year-old man underwent surveillance colonoscopy.

The article discusses a study which is aimed to evaluate the performance of artificial intelligence (AI)-assisted endocytoscopy in the clinical setting, which supports optical biopsy of colorectal polyps. In AI-assisted endocytoscopy, images acquired by an endocytoscope are analyzed in real time during colonoscopy. The study assessed 144 diminutive polyps using AI-assisted endocytoscopy.

Precision endoscopy in the management of colorectal polyps and early colorectal cancer has emerged as the standard of care. It includes optical characterization of polyps and estimation of submucosal invasion depth of large nonpedunculated colorectal polyps to select the appropriate endoscopic resection modality. Over time, several imaging modalities have been implemented in endoscopic practice to improve optical performance. Among these, image‐enhanced endoscopy systems and magnification endoscopy represent now well‐established tools. New advanced technologies, such as endocytoscopy and confocal laser endomicroscopy, have recently shown promising results in predicting the histology of colorectal polyps. In recent years, artificial intelligence has continued to enhance endoscopic performance in the characterization of colorectal polyps, overcoming the limitations of other imaging modes. In this review we retrace the path of precision endoscopy, analyzing the yield of various endoscopic imaging techniques in personalizing management of colorectal polyps and early colorectal cancer. [ABSTRACT FROM AUTHOR]

Watch a video of this article. [ABSTRACT FROM AUTHOR]

Meticulous inspection of the mucosa during colonoscopy, represents a lengthier withdrawal time, but has been shown to increase adenoma detection rate (ADR). We investigated if artificial intelligence-aided speed monitoring can improve suboptimal withdrawal time. We evaluated the implementation of a computer-aided speed monitoring device during colonoscopy at a large academic endoscopy center. After informed consent, patients ≥18 years undergoing colonoscopy between 5 March and 29 April 2021 were examined without the use of the speedometer, and with the speedometer between 29 April and 30 June 2021. All colonoscopies were recorded, and withdrawal time was assessed based on the recordings in a blinded fashion. We compared mean withdrawal time, percentage of withdrawal time ≥6 min, and ADR with and without the speedometer. One hundred sixty-six patients in each group were eligible for analyses. Mean withdrawal time was 9 min and 6.6 s (95% CI: 8 min and 34.8 s to 9 min and 39 s) without the use of the speedometer, and 9 min and 9 s (95% CI: 8 min and 45 s to 9 min and 33.6 s) with the speedometer; difference 2.3 s (95% CI: −42.3–37.7, p = 0.91). The ADRs were 45.2% (95% CI: 37.6–52.8) without the speedometer as compared to 45.8% (95% CI: 38.2–53.4) with the speedometer (p = 0.91). The proportion of colonoscopies with withdrawal time ≥6 min without the speedometer was 85.5% (95% CI: 80.2–90.9) versus 86.7% (95% CI: 81.6–91.9) with the speedometer (p = 0.75). Use of speed monitoring during withdrawal did not increase withdrawal time or ADR in colonoscopy. NCT04710251 [ABSTRACT FROM AUTHOR]

The number of artificial intelligence (AI) tools for colonoscopy on the market is increasing with supporting clinical evidence. Nevertheless, their implementation is not going smoothly for a variety of reasons, including lack of data on clinical benefits and cost‐effectiveness, lack of trustworthy guidelines, uncertain indications, and cost for implementation. To address this issue and better guide practitioners, the World Endoscopy Organization (WEO) has provided its perspective about the status of AI in colonoscopy as the position statement. WEO Position Statement: Statement 1.1: Computer‐aided detection (CADe) for colorectal polyps is likely to improve colonoscopy effectiveness by reducing adenoma miss rates and thus increase adenoma detection; Statement 1.2: In the short term, use of CADe is likely to increase health‐care costs by detecting more adenomas; Statement 1.3: In the long term, the increased cost by CADe could be balanced by savings in costs related to cancer treatment (surgery, chemotherapy, palliative care) due to CADe‐related cancer prevention; Statement 1.4: Health‐care delivery systems and authorities should evaluate the cost‐effectiveness of CADe to support its use in clinical practice; Statement 2.1: Computer‐aided diagnosis (CADx) for diminutive polyps (≤5 mm), when it has sufficient accuracy, is expected to reduce health‐care costs by reducing polypectomies, pathological examinations, or both; Statement 2.2: Health‐care delivery systems and authorities should evaluate the cost‐effectiveness of CADx to support its use in clinical practice; Statement 3: We recommend that a broad range of high‐quality cost‐effectiveness research should be undertaken to understand whether AI implementation benefits populations and societies in different health‐care systems. [ABSTRACT FROM AUTHOR]