Standard-definition White-light,High-definition White-light versus Narrow-band Imaging Endoscopy for Detecting Colorectal Adenomas:A Multicenter Randomized Controlled Trial

Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colorectal lesions in the Chinese population.Methods This was a multicenter,single-blind,randomized,controlled trial with a non-inferiority design.Patients undergoing endoscopy for physical examination,screening,and surveillance were enrolled from July 2017 to December 2020.The primary outcome measure was the adenoma detection rate(ADR),defined as the proportion of patients with at least one adenoma detected.The associated factors for detecting adenomas were assessed using univariate and multivariate logistic regression.Results Out of 653 eligible patients enrolled,data from 596 patients were analyzed.The ADRs were 34.5%in the SD-WL group,33.5%in the HD-WL group,and 37.5%in the HD-NBI group(P=0.72).The advanced neoplasm detection rates(ANDRs)in the three arms were 17.1%,15.5%,and 10.4%(P=0.17).No significant differences were found between the SD group and HD group regarding ADR or ANDR(ADR:34.5%vs.35.6%,P=0.79;ANDR:17.1%vs.13.0%,P=0.16,respectively).Similar results were observed between the HD-WL group and HD-NBI group(ADR:33.5%vs.37.7%,P=0.45;ANDR:15.5%vs.10.4%,P=0.18,respectively).In the univariate and multivariate logistic regression analyses,neither HD-WL nor HD-NBI led to a significant difference in overall adenoma detection compared to SD-WL(HD-WL:OR 0.91,P=0.69;HD-NBI:OR 1.15,P=0.80).Conclusion HD-NBI and HD-WL are comparable to SD-WL for overall adenoma detection among Chinese outpatients.It can be concluded that HD-NBI or HD-WL is not superior to SD-WL,but more effective instruction may be needed to guide the selection of different endoscopic methods in the future.Our study’s conclusions may aid in the efficient allocation and utilization of limited colonoscopy resources,especially advanced imaging technologies.

Could near focus endoscopy,narrow-band imaging,and acetic acid improve the visualization of microscopic features of stomach mucosa?

BACKGROUND Conventional magnifying endoscopy with narrow-band imaging(NBI)observation of the gastric body mucosa shows dominant patterns in relation to the regular arrangement of collecting venules,subepithelial capillary network,and gastric pits.AIM To evaluate the effectiveness of a new one-dual(near)focus,NBI mode in the assessment of the microscopic features of gastric body mucosa compared to conventional magnification.METHODS During 2021 and 2022,68 patients underwent proximal gastrointestinal endoscopy using magnification endoscopic modalities subsequently applying acetic acid(AA).The GIF-190HQ series NBI system with dual focus capability was used for the investigation of gastric mucosa.At the time of the endoscopy,the gastric body mucosa of all enrolled patients was photographed using the white light endoscopy(WLE),near focus(NF),NF-NBI,AA-NF,and AA-NF-NBI modes.RESULTS The WLE,NF and NF-NBI endoscopic modes for all patients(204 images)were classified in the same order into three groups.Two images from each patient for the AA-NF and AA-NF-NBI endoscopic modes were classified in the same order.According to all three observers who completed the work independently,NF magnification was significantly superior to WLE(P<0.01),and the NF-NBI mode was significantly superior to NF magnification(P<0.01).After applying AA,the three observers confirmed that AA-NF-NBI was significantly superior to AA-NF(P<0.01).Interobserver kappa values for WLE were 0.609,0.704,and 0.598,respectively and were 0.600,0.721,and 0.637,respectively,for NF magnification.For the NF-NBI mode,the values were 0.378,0.471,and 0.553,respectively.For AA-NF,they were 0.453,0.603,and 0.480,respectively,and for AA-NF-NBI,they were 0.643,0.506,and 0.354,respectively.CONCLUSION When investigating gastric mucosa in microscopic detail,NF-NBI was the most powerful endoscopic mode for assessing regular arrangement of collecting venules,subepithelial capillary network,and gastric pits among the five endoscopic modalities investigated in this study.AA-NF-NBI was the most powerful endoscopic mode for analyzing crypt opening and intervening part.

Magnifying narrow-band imaging endoscopy is superior in diagnosis of early gastric cancer

AIM:To evaluate the diagnostic effectiveness of white light endoscopy,magnifying endoscopy(ME),and magnifying narrow-band imaging endoscopy(ME-NBI) in detecting early gastric cancer(EGC).METHODS:From March 2010 to June 2012,a total of 3616 patients received screening for gastric cancer by magnifying endoscopy. There were 3675 focal gastric lesions detected using conventional high definition white light endoscopy(HD-WLE) in four different referentialhospitals that were recruited for further investigation using ME and ME-NBI. The images obtained from HD-WLE,ME,and ME-NBI were reviewed by four experienced endoscopists to evaluate their diagnostic effectiveness for EGC. The diagnosis of cancerous and non-cancerous lesions was conducted by evaluating the microvascular and microsurface patterns using the VS classification system. The final endoscopic diagnosis of each lesion was determined by consultation when a disagreement occurred. We used histopathological results as the gold standard for the diagnosis of EGC.RESULTS:Among the 3675 lesions found,1508 were validated by pathological findings as chronic gastritis,1279 as chronic gastritis with intestinal metaplasia,631 as low-grade neoplasia,and 257 as EGC. The sensitivity,specificity,positive predictive value,negative predictive value,and accuracy of HD-WLE for the diagnosis of EGC were 71.2%,99.1%,85.5%,97.9% and 97.1%,respectively. The results of ME for diagnosing EGC were 81.3%,98.8%,83.3%,98.6% and 97.6%,respectively. The results of ME-NBI for the diagnosis of EGC were 87.2%,98.6%,82.1%,99.0% and 97.8%,respectively. The diagnostic sensitivity and accuracy of paired ME and ME-NBI were significantly better than those of HD-WLE(P < 0.05).CONCLUSION:HD-WLE has a relatively high accuracy for diagnosing EGC and is an effective screening tool. Further investigations of ME and ME-NBI are required to achieve superior accuracy.

Narrow-band imaging with magnifying endoscopy for the evaluation of gastrointestinal lesions

Narrow band imaging(NBI) endoscopy is an optical image enhancing technology that allows a detailed inspection of vascular and mucosal patterns, providing the ability to predict histology during real-time endoscopy. By combining NBI with magnification endoscopy(NBI-ME), the accurate assessment of lesions in the gastrointestinal tract can be achieved, as well as the early detection of neoplasia by emphasizing neovascularization. Promising results of the method in the diagnosis of premalignant and malignant lesions of gastrointestinal tract have been reported in clinical studies. The usefulness of NBI-ME as an adjunct to endoscopic therapy in clinical practice, the potential to improve diagnostic accuracy, surveillance strategies and cost-saving strategies based on this method are summarized in this review. Various classification systems of mucosal and vascular patterns used to differentiate preneoplastic and neoplastic lesions have been reviewed. We concluded that the clinical applicability of NBI-ME has increased, but standardization of endoscopic criteria and classification systems, validation in randomized multicenter trials and training programs to improve the diagnostic performance are all needed before the widespread acceptance of the method in routine practice. However, published data regarding the usefulness of NBI endoscopy are relevant in order to recommend the method as a reliable tool in diagnostic and therapy, even for less experienced endoscopists.

Narrow-band imaging with magnifying endoscopy is accurate for detecting gastric intestinal metaplasia

AIM:To investigate the predictive value of narrowband imaging with magnifying endoscopy (NBI-ME) for identifying gastric intestinal metaplasia (GIM) in unselected patients. METHODS:We prospectively evaluated consecutive patients undergoing upper endoscopy for various indications, such as epigastric discomfort/pain, anaemia, gastro-oesophageal reflux disease, suspicion of peptic ulcer disease, or chronic liver diseases. Patients underwent NBI-ME, which was performed by three blinded, experienced endoscopists. In addition, five biopsies (2 antrum, 1 angulus, and 2 corpus) were taken and examined by two pathologists unaware of the endoscopic findings to determine the presence or absence of GIM. The correlation between light blue crest (LBC) appearance and histology was measured. Moreover, we quantified the degree of LBC appearance as less than 20% (+), 20%-80% (++) and more than 80% (+++) of an image field, and the semiquantitative evaluation of LBC appearance was correlated with IM percentage from the histological findings. RESULTS:We enrolled 100 (58 F/42 M) patients who were mainly referred for gastro-esophageal reflux disease/dyspepsia (46%), cancer screening/anaemia (34%), chronic liver disease (9%), and suspected celiac disease (6%); the remaining patients were referred for other indications. The prevalence of Helicobacter pylori (H. pylori ) infection detected from the biopsies was 31%, while 67% of the patients used proton pump inhibitors. LBCs were found in the antrum of 33 patients (33%); 20 of the cases were classified as LBC+, 9 as LBC++, and 4 as LBC+++. LBCs were found in the gastric body of 6 patients (6%), with 5 of them also having LBCs in the antrum. The correlation between the appearance of LBCs and histological GIM was good, with a sensitivity of 80% (95%CI:67-92), a specificity of 96% (95%CI:93-99), a positive predictive value of 84% (95%CI:73-96), a negative predictive value of 95% (95%CI:92-98), and an accuracy of 93% (95%CI:90-97). The NBI-ME examination overlooked GIM in 8 cases, but the GIM was less than 5% in 7 of the cases. Moreover, in the 6 false positive cases, the histological examination showed the presence of reactive gastropathy (4 cases) or H. pylori active chronic gastritis (2 cases). The semiquantitative correlation between the rate of LBC appearance and the percentage of GIM was 79% (P < 0.01). CONCLUSION:NBI-ME achieved good sensitivity and specificity in recognising GIM in an unselected population. In routine clinical practice, this technique can reliably target gastric biopsies.

Standard vs magnifying narrow-band imaging endoscopy for diagnosis of Helicobacter pylori infection and gastric precancerous conditions

BACKGROUND Advances in endoscopic imaging enable the identification of patients at high risk of gastric cancer.However,there are no comparative data on the utility of standard and magnifying narrow-band imaging(M-NBI)endoscopy for diagnosing Helicobacter pylori(H.pylori)infection,gastric atrophy,and intestinal metaplasia.AIM To compare the diagnostic performance of standard and M-NBI endoscopy for H.pylori gastritis and precancerous conditions.METHODS In 254 patients,standard endoscopy findings were classified into mosaic-like appearance(type A),diffuse homogenous redness(type B),and irregular redness with groove(type C).Gastric mucosal patterns visualized by M-NBI were classified as regular round pits with polygonal sulci(type Z-1),more dilated and linear pits without sulci(type Z-2),and loss of gastric pits with coiled vessels(type Z-3).RESULTS The diagnostic accuracy of standard and M-NBI endoscopy for H.pylori gastritis was 93.3%and 96.1%,respectively.Regarding gastric precancerous conditions,the accuracy of standard and M-NBI endoscopy was 72.0%vs 72.6%for moderate to severe atrophy,and 61.7%vs.61.1%for intestinal metaplasia in the corpus,respectively.Compared to type A and Z-1,types B+C and Z-2+Z-3 were significantly associated with moderate to severe atrophy[odds ratio(OR)=5.56 and 8.67]and serum pepsinogen I/II ratio of≤3(OR=4.48 and 5.69).CONCLUSION Close observation of the gastric mucosa by standard and M-NBI endoscopy is useful for the diagnosis of H.pylori gastritis and precancerous conditions.

Narrow-band imaging endoscopy with and without magnification in diagnosis of colorectal neoplasia

AIM:To evaluate the diagnostic efficacies of narrowband imaging(NBI) endoscopy with and without high magnification in distinguishing neoplasia from nonneoplasia colorectal lesions.METHODS:A total of 118 patients with 123 colorectal lesions examined by NBI endoscopy in the Zhejiang Provincial People's Hospital from September 2008 to April 2010 were enrolled in this study.These lesions were classified by pit pattern and capillary pattern,and then assessed by histopathology.RESULTS:Ten lesions not meeting the diagnostic criteria were excuded,the overall diagnostic accuracy of NBI endoscopy in distinguishing neoplasia from non-neoplasia colorectal lesions was 91.2%(103/113),and that of NBI endoscopy with and without high magnification was 93.0%(40/43) and 90.0%(63/70),respectively.Both were significantly higher than that of conventional colonoscopy reported in the literature(P < 0.05),but there was no significant difference between the two groups(P > 0.05).CONCLUSION:Besides NBI magnifying endoscopy,NBI endoscopy without magnification may also be used to distinguish neoplasia from non-neoplasia colorectal lesions.

Role of magnifying narrow-band imaging endoscopy for diagnosis of Helicobacter pylori infection and gastric precancerous conditions:Few issues

Standard endoscopy with biopsy and narrow-band imaging with guided biopsy are techniques for the detection of Helicobacter pylori(H.pylori)-related gastritis and precancerous lesions.In this study,the authors compared standard endoscopy and magnified narrow-band imaging(commonly known as NBI-M)in the diagnosis of H.pylori infections,atrophic gastritis,and intestinal metaplasia.Although the sensitivity of NBI-M is better than standard endoscopy,the diagnostic accuracy did not differ substantially between the diagnostic modalities.Future prospective studies may guide endoscopists in difficult cases regarding which modality is more useful and cost-effective for the diagnosis of H.pylorirelated gastritis and precancerous conditions.

Topic highlight on texture and color enhancement imaging in gastrointestinal diseases

Olympus Corporation developed texture and color enhancement imaging(TXI)as a novel image-enhancing endoscopic technique.This topic highlights a series of hot-topic articles that investigated the efficacy of TXI for gastrointestinal disease identification in the clinical setting.A randomized controlled trial demonstrated improvements in the colorectal adenoma detection rate(ADR)and the mean number of adenomas per procedure(MAP)of TXI compared with those of white-light imaging(WLI)observation(58.7%vs 42.7%,adjusted relative risk 1.35,95%CI:1.17-1.56;1.36 vs 0.89,adjusted incident risk ratio 1.48,95%CI:1.22-1.80,respectively).A cross-over study also showed that the colorectal MAP and ADR in TXI were higher than those in WLI(1.5 vs 1.0,adjusted odds ratio 1.4,95%CI:1.2-1.6;58.2%vs 46.8%,1.5,1.0-2.3,respectively).A randomized controlled trial demonstrated non-inferiority of TXI to narrow-band imaging in the colorectal mean number of adenomas and sessile serrated lesions per procedure(0.29 vs 0.30,difference for non-inferiority-0.01,95%CI:-0.10 to 0.08).A cohort study found that scoring for ulcerative colitis severity using TXI could predict relapse of ulcerative colitis.A cross-sectional study found that TXI improved the gastric cancer detection rate compared to WLI(0.71%vs 0.29%).A cross-sectional study revealed that the sensitivity and accuracy for active Helicobacter pylori gastritis in TXI were higher than those of WLI(69.2%vs 52.5%and 85.3%vs 78.7%,res-pectively).In conclusion,TXI can improve gastrointestinal lesion detection and qualitative diagnosis.Therefore,further studies on the efficacy of TXI in clinical practice are required.

Diagnostic performance of magnifying narrow-band imaging for early gastric cancer: A meta-analysis

AIM: To investigate the performance of magnifying endoscopy with narrow-band imaging(ME-NBI) in the diagnosis of early gastric cancer(EGC).METHODS: Systematic literature searches were conducted until February 2014 in Pub Med, EMBASE, Web of Science, Ovid, Scopus and the Cochrane Library databases by two independent reviewers. Meta-analysis was performed to calculate the pooled sensitivity, specificity and diagnostic odds ratio and to construct a summary receiver operating characteristic(ROC) curve. Subgroup analyses were performed based on the morphology type of lesions, diagnostic standard, the size of lesions, type of assessment, country and sample size to explore possible sources of heterogeneity. A Deeks' asymmetry test was used to evaluate the publication bias.RESULTS: Fourteen studies enrolling 2171 patients were included. The pooled sensitivity, specificity and diagnostic odds ratio for ME-NBI diagnosis of EGC were 0.86(95%CI: 0.83-0.89), 0.96(95%CI: 0.95-0.97) and 102.75(95%CI: 48.14-219.32), respectively, with the area under ROC curve being 0.9623. Among the 14 studies, six also evaluated the diagnostic value of conventional white-light imaging, with a sensitivityof 0.57(95%CI: 0.50-0.64) and a specificity of 0.79(95%CI: 0.76-0.81). When using "VS"(vessel plus surface) ME-NBI diagnostic systems in gastric lesions of depressed macroscopic type, the pooled sensitivity and specificity were 0.64(95%CI: 0.52-0.75) and 0.96(95%CI: 0.95-0.98). For the lesions with a diameter less than 10 mm, the sensitivity and specificity were 0.74(95%CI: 0.65-0.82) and 0.98(95%CI: 0.97-0.98).CONCLUSION: ME-NBI is a promising endoscopic tool in the diagnosis of early gastric cancer and might be helpful in further target biopsy.

Investigation of relationships among gastroesophageal reflux disease subtypes using narrow band imaging magnifying endoscopy

AIM:To investigate the relationships among subtypes of gastroesophageal reflux disease(GERD)using narrow band imaging(NBI)magnifying endoscopy.METHODS:A reflux disease questionnaire was used to screen 120 patients representing the three subtypes of GERD(n=40 for each subtypes):nonerosive reflux disease(NERD),reflux esophagitis(RE)and Barrett’s esophagus(BE).NBI magnifying endoscopic procedure was performed on the patients as well as on 40 healthy controls.The demographic and clinical characteristics,and NBI magnifying endoscopic features,were recorded and compared among the groups.Targeted biopsy and histopathological examination were conducted if there were any abnormalities.SPSS 18.0 software was used for all statistical analysis.RESULTS:Compared with healthy controls,a significantly higher proportion of GERD patients had increased number of intrapapillary capillary loops(IPCLs)(78.3%vs 20%,P<0.05),presence of microerosions(41.7%vs 0%,P<0.05),and a non-round pit pattern below the squamocolumnar junction(88.3%vs 30%,P<0.05).The maximum(228±4.8 vs 144±4.7,P<0.05),minimum(171±3.8 vs 103±4.4,P<0.05),and average(199±3.9 vs 119±3.9,P<0.05)numbers of IPCLs/field were also significantly greater in GERD patients.However,comparison among groups of the three subtypes showed no significant differences or any linear trend,except that microerosions were present in 60%of the RE patients,but in only 35%and 30%of the NERD and BE patients,respectively(P<0.05).CONCLUSION:Patients with GERD,irrespective of subtype,have similar micro changes in the distal esophagus.The three forms of the disease are probably independent of each other.

Clinical relevance of fluorodeoxyglucose positron emission tomography/computed tomography and magnifying endoscopy with narrow band imaging in decision-making regarding the treatment strategy for esophageal squamous cell carcinoma

BACKGROUND Recent advances in endoscopic technology,especially magnifying endoscopy with narrow band imaging(ME-NBI)enable us to detect superficial esophageal squamous cell carcinoma(ESCC),but determining the appropriate method of resection,endoscopic resection(ER)vs surgical resection,is often challenging.Recently,several studies have reported that 18F-fluorodeoxyglucose positron emission tomography(FDG-PET)is a useful indicator for decision-making regarding treatment for superficial ESCC.Although,there are not enough reports on association between FDG-PET uptake and clinicopathological characteristics of superficial ESCC.And,there are not enough reports on evaluating the usefulness of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC.This study evaluated clinical relevance of FDG-PET and ME-NBI in decision-making regarding the treatment strategy for ESCC.AIM To investigate the association between FDG uptake and the clinicopathological characteristics of superficial ESCC and its usefulness of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC.METHODS A database of all patients with superficial ESCC who had undergone both MENBI and FDG-PET for pre-treatment staging at Aichi Cancer Center Hospital between January 2008 and November 2018 was retrospectively analyzed.FDG uptake was defined positive or negative whether the primary lesion was visualized or could be distinguished from the background,or not.The invasion depth of ESCC was classified according to the Japan Esophageal Society.Primary endpoint is to evaluate the association between FDG uptake and clinicopathological characteristics of superficial ESCC.Secondary endpoint is to investigate the efficacy of combination of FDG-PET and ME-NBI for determining the treatment strategy for superficial ESCC.RESULTS A total of 82 lesions in 82 patients were included.FDG-PET showed positive uptake in 29(35.4%)lesions.Univariate analysis showed that uptake of FDG-PET had significant correlations with circumferential extension(P=0.014),pathological depth of tumor invasion(P<0.001),infiltrative growth pattern(P<0.001),histological grade(P=0.002),vascular invasion(P=0.001),and lymphatic invasion(P<0.001).On multivariate analysis,only depth of tumor invasion was independently correlated with FDG-PET/computed tomography visibility(P=0.018).The sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV),and accuracy of Type B2 in ME-NBI for the invasion depth of T1a muscularis mucosae and T1b upper submucosal layer were 68.4%/79.4%/50.0%/89.3%/76.8%,respectively,and those of Type B3 for the depth of T1b middle and deeper submucosal layers(SM2 and SM3)were 46.7%/100%/100%/89.3%/90.2%,respectively.On the other hand,those of FDGPET for SM2 and SM3 were 93.3%/77.6%/48.2%/98.1%/80.5%,respectively,whereas,if the combination of positive FDG uptake and type B2 and B3 was defined as an indicator for radical esophagectomy or definitive chemoradiotherapy,the sensitivity,specificity,PPV,NPV,and accuracy were 78.3%/91.5%/78.3%/91.5%/87.8%,respectively.CONCLUSION FDG uptake was correlated with the invasion depth of superficial ESCC.Combined use of FDG-PET and ME-NBI,especially with the microvascular findings of Type B2 and B3,is useful to determine whether ER is indicated for the lesion.

Diagnostic performance of narrow-band imaging international colorectal endoscopic and Japanese narrow-band imaging expert team classification systems for colorectal cancer and precancerous lesions

BACKGROUND In recent years,two new narrow-band imaging(NBI)classifications have been proposed:The NBI international colorectal endoscopic(NICE)classification and Japanese NBI expert team(JNET)classification.Most validation studies of the two new NBI classifications were conducted in classification setting units by experienced endoscopists,and the application of use in different centers among endoscopists with different endoscopy skills remains unknown.AIM To evaluate clinical application and possible problems of NICE and JNET classification for the differential diagnosis of colorectal cancer and precancerous lesions.METHODS Six endoscopists with varying levels of experience participated in this study.Eighty-seven consecutive patients with a total of 125 lesions were photographed during non-magnifying conventional white-light colonoscopy,non-magnifying NBI,and magnifying NBI.The three groups of endoscopic pictures of each lesion were evaluated by the six endoscopists in randomized order using the NICE and JENT classifications separately.Then we calculated the six endoscopists’sensitivity,specificity,accuracy,positive predictive value,and negative predictive value for each category of the two classifications.RESULTS The sensitivity,specificity,and accuracy of JNET classification type 1 and 3 were similar to NICE classification type 1 and 3 in both the highly experienced endoscopist(HEE)and less-experienced endoscopist(LEE)groups.The specificity of JNET classification type 1 and 3 and NICE classification type 3 in both the HEE and LEE groups was>95%,and the overall interobserver agreement was good in both groups.The sensitivity of NICE classification type 3 lesions for diagnosis of SM-d carcinoma in the HEE group was significantly superior to that in the LEE group(91.7%vs 83.3%;P=0.042).The sensitivity of JNET classification type 2B lesions for the diagnosis of high-grade dysplasia or superficial submucosal invasive carcinoma in the HEE and LEE groups was 53.8%and 51.3%,respectively.Compared with other types of JNET classification,the diagnostic ability of type 2B was the weakest.CONCLUSION The treatment strategy of the two classification type 1 and 3 lesions can be based on the results of endoscopic examination.JNET type 2B lesions need further examination.

Two cases of adenocarcinoma occurring in sporadic fundic gland polyps observed by magnifying endoscopy with narrow band imaging

Gastric fundic gland polyps(FGPs) are common nonadenomatous gastric polyps arising from normal fundic mucosa without Helicobacter pylori(H. pylori) infection. Although systemic FGPs associated with familial adenomatous polyposis(FAP) often have dysplasia, there are few reports of dysplasia occurring in sporadic F G P s, e s p e c i a l l y w h e n d e t e c t e d b y m a g n i f y i n g endoscopy with narrow band imaging(ME-NBI). We experienced two cases of adenocarcinoma occurring in sporadic FGPs, and their ME-NBI findings were very useful for differentiating FGP with cancer from nondysplastic FGP. A 68-year-old man and a 63-year-old woman were referred to our institution for medical checkup. H. pylori was negative in both patients. Endoscopic examination revealed a small reddishpolypoid lesion on the anterior wall of the upper gastric body and several FGPs. ME-NBI showed an irregular microvascular architecture composed of closed loop- or open loop-type vascular components, plus an irregular microsurface structure composed of oval-type surface components which was different from that of FGPs. FAP was denied because of the absence of colon polyps and no familial history of FAP. Pathological diagnosis was adenocarcinoma occurring in sporadic FGP.

Diagnostic utility of narrow-band imaging endoscopy for pharyngeal superfi cial carcinoma

AIM: To investigate the endoscopic features of pharyngeal superfi cial carcinoma and evaluate the utility of narrow-band imaging (NBI) for this disease. METHODS: In the present prospective study, 335 patients underwent conventional white light (CWL) en-doscopy and non-magnifi ed/magnifi ed NBI endoscopy, followed by an endoscopic biopsy, for 445 superfi cial lesions in the oropharynx and hypopharynx. The macroscopic appearance of superfi cial lesions was categorized as either elevated (< 5 mm in height), flat, or depressed (not ulcerous). Superficial carcinoma (SC) was defi ned as a superfi cial lesion showing high-grade dysplasia or squamous cell carcinoma on histology. The color, delineation, and macroscopic appearances of the lesions were evaluated by CWL endoscopy. The ratio of the brownish area/intervascular brownish epithelium (IBE), as well as microvascular proliferation, dilation, and irregularities, was determined by non-magnifi ed/ magnifi ed NBI endoscopy. An experienced pathologist who was unaware of the endoscopic fi ndings made the histological diagnoses. By comparing endoscopic fi ndings with histology, we determined the endoscopic features of SC and evaluated the diagnostic utility of NBI. RESULTS: The 445 lesions were divided histologically into two groups: a non-SC group, including non-neoplasia and low-grade dysplasia cases, and an SC group. Of the 445 lesions examined, 333 were classified as non-SC and 112 were classif ied as SC. There were no significant differences in age, gender, or the location of the lesions between the patients in the two groups. The mean diameter of the SC lesions was signif icantly greater than that of non-SC lesions (11.0 ± 7.6 mm vs 4.6 ± 3.6 mm, respectively, P < 0.001). Comparisons of CWL endoscopy fi ndings for SC and non-SC lesions by univariate analysis revealed that the incidence of redness (72% vs 41%, respectively, P < 0.001) and a flat or depressed type of lesion (58% vs 44%, respectively, P = 0.013) was significantly higher in the SC group. Using non-magnifi ed NBI endoscopy, the incidence of a brownish area was signifi cantly higher for SC lesions (79% vs 57%, respectively, P < 0.001). On magnifi ed NBI endoscopy, the incidence of IBE (68% vs 33%, P < 0.001) and microvascular proliferation (82% vs 51%, P < 0.001), dilation (90% vs 76%, P =0.002), and irregularity (82% vs 31%, P < 0.001) was also signifi cantly higher for the SC compared with the non-SC lesions. Multivariate analysis revealed that the incidence of redness (P = 0.022) on CWL endoscopy and IBE (P < 0.001) and microvascular irregularities (P < 0.001) on magnif ied NBI endoscopy was signif icantly higher in SC than non-SC lesions. Redness alone exhibited signifi cantly higher sensitivity and signifi cantly lower specifi city for the diagnosis of SC compared with redness plus IBE and microvascular irregularities (72% vs 52%, P = 0.002; and 59% vs 92%, P < 0.001, respectively). The accuracy of redness plus IBE and irregularities for the diagnosis of SC was signifi cantly greater than using redness alone (82% vs 62%, respectively, P < 0.001). CONCLUSION: Redness, IBE, and microvascular irregularities appear to be closely related to SC lesions. Magnifi ed NBI endoscopy may increase the diagnostic accuracy of CWL endoscopy for SC.

Brown slits for colorectal adenoma crypts on conventional magnifying endoscopy with narrow band imaging using the X1 system

BACKGROUND Accurate diagnosis of colorectal premalignant polyps,including adenomas,is vital in clinical practice.AIM To investigate the diagnostic yields of novel findings of brown slits for adenomas.METHODS Patients who underwent colonoscopy at the Toyoshima Endoscopy Clinic were enrolled.Polyps sized≥5 mm suspected of adenomas or clinically significant serrated polyps were included in the study.We defined the surface structures of colorectal polyps,which were brown curves inside and along the tubular glands identified using a combination of a new X1 system(Olympus Corporation)and a conventional magnifying colonoscope with non-staining narrow band imaging(NBI),as brown slits.The brown slits corresponded to slit-like lumens on endocytoscopy and histological crypt openings of an adenoma.We evaluated the diagnostic performance of brown slits for adenoma.RESULTS A total of 108 Lesions from 62 patients were eligible.The average age was 60.4 years and 41.9%were male.The mean polyp size was 7.45±2.83 mm.Fifty-seven lesions were positive for brown slits.Histopathological diagnosis comprised 59 low-grade tubular adenomas,16 sessile serrated lesions,and 33 hyperplastic polyps.Among 59 adenomas,56(94.9%)were positive for brown slits.Among 16 sessile serrated lesions,0(0%)was positive for brown slits.Among 33 hyperplastic polyps,1(3.0%)was positive for brown slits.The sensitivity,specificity,and accuracy of brown slits for adenoma were 94.9%,98.0%,and 96.3%,respectively.The positive predictive value and negative predictive value of brown slits for adenoma were also excellent for 98.2%,and 94.1%,respectively.CONCLUSION Brown slits on conventional magnifying endoscopy with non-staining NBI using the X1 system were useful for diagnosing colorectal adenoma.The new endoscopy system could be examined using new standards.

Simplified criteria for diagnosing superficial esophageal squamous neoplasms using Narrow Band Imaging magnifying endoscopy

AIM To simplify the diagnostic criteria for superficial esophageal squamous cell carcinoma(SESCC) on Narrow Band Imaging combined with magnifying endoscopy(NBI-ME).METHODS This study was based on the post-hoc analysis of a randomized controlled trial. We performed NBI-ME for 147 patients with present or a history of squamous cell carcinoma in the head and neck, or esophagus between January 2009 and June 2011. Two expert endoscopistsdetected 89 lesions that were suspicious for SESCC lesions, which had been prospectively evaluated for the following 6 NBI-ME findings in real time: "intervascular background coloration"; "proliferation of intrapapillary capillary loops(IPCL)"; and "dilation", "tortuosity", "change in caliber", and "various shapes(VS)" of IPCLs(i.e., Inoue's tetrad criteria). The histologic examination of specimens was defined as the gold standard for diagnosis. A stepwise logistic regression analysis was used to identify candidates for the simplified criteria from among the 6 NBI-ME findings for diagnosing SESCCs. We evaluated diagnostic performance of the simplified criteria compared with that of Inoue's criteria.RESULTS Fifty-four lesions(65%) were histologically diagnosed as SESCCs and the others as low-grade intraepithelial neoplasia or inflammation. In the univariate analysis, proliferation, tortuosity, change in caliber, and VS were significantly associated with SESCC(P < 0.01). The combination of VS and proliferation was statistically extracted from the 6 NBI-ME findings by using the stepwise logistic regression model. We defined the combination of VS and proliferation as simplified dyad criteria for SESCC. The areas under the curve of the simplified dyad criteria and Inoue's tetrad criteria were 0.70 and 0.73, respectively. No significant difference was shown between them. The sensitivity, specificity, and accuracy of diagnosis for SESCC were 77.8%, 57.1%, 69.7% and 51.9%, 80.0%, 62.9% for the simplified dyad criteria and Inoue's tetrad criteria, respectively.CONCLUSION The combination of proliferation and VS may serve as simplified criteria for the diagnosis of SESCC using NBIME.

Narrow band imaging with magnification for the diagnosis of lesions in the upper gastrointestinal tract

Endoscopy plays an important role in the diagnosis and management of gastrointestinal(GI)tract disorders.Chromoendoscopy has proven to be superior to white light endoscopy for early detection of various GI lesions.This has however been fraught with problems.The use of color stains,time taken to achieve an effect and the learning curve associated with the technique has been some of the pitfalls.Narrow band imaging(NBI)particularly in combination with magnifying endoscopy may allow the endoscopist to accomplish a fairly accurate diagnosis with good histological correlation similar to results achieved with chromoendoscopy.Such enhanced detection of pre-malignant and early neoplastic lesions in the gastrointestinal tract should allow better targeting of biopsies and could ultimately prove to be cost effective.Various studies have been done demonstrating the utility of this novel technology.This article will review the impact of NBI in the diagnosis of upper gastrointestinal tract disorders.

Comparative study on artificial intelligence systems for detecting early esophageal squamous cell carcinoma between narrow-band and white-light imaging

BACKGROUND Non-magnifying endoscopy with narrow-band imaging(NM-NBI)has been frequently used in routine screening of esophagus squamous cell carcinoma(ESCC).The performance of NBI for screening of early ESCC is,however,significantly affected by operator experience.Artificial intelligence may be a unique approach to compensate for the lack of operator experience.AIM To construct a computer-aided detection(CAD)system for application in NMNBI to identify early ESCC and to compare it with our previously reported CAD system with endoscopic white-light imaging(WLI).METHODS A total of 2167 abnormal NM-NBI images of early ESCC and 2568 normal images were collected from three institutions(Zhongshan Hospital of Fudan University,Xuhui Hospital,and Kiang Wu Hospital)as the training dataset,and 316 pairs of images,each pair including images obtained by WLI and NBI(same part),were collected for validation.Twenty endoscopists participated in this study to review the validation images with or without the assistance of the CAD systems.The diagnostic results of the two CAD systems and improvement in diagnostic efficacy of endoscopists were compared in terms of sensitivity,specificity,accuracy,positive predictive value,and negative predictive value.RESULTS The area under receiver operating characteristic curve for CAD-NBI was 0.9761.For the validation dataset,the sensitivity,specificity,accuracy,positive predictive value,and negative predictive value of CAD-NBI were 91.0%,96.7%,94.3%,95.3%,and 93.6%,respectively,while those of CAD-WLI were 98.5%,83.1%,89.5%,80.8%,and 98.7%,respectively.CAD-NBI showed superior accuracy and specificity than CAD-WLI(P=0.028 and P≤0.001,respectively),while CAD-WLI had higher sensitivity than CAD-NBI(P=0.006).By using both CAD-WLI and CAD-NBI,the endoscopists could improve their diagnostic efficacy to the highest level,with accuracy,sensitivity,and specificity of 94.9%,92.4%,and 96.7%,respectively.CONCLUSION The CAD-NBI system for screening early ESCC has higher accuracy and specificity than CAD-WLI.Endoscopists can achieve the best diagnostic efficacy using both CAD-WLI and CAD-NBI.

Narrow-band imaging observation of colorectal lesions using NICE classification to avoid discarding significant lesions

AIM: To assess the risk of failing to detect diminutive and small colorectal cancers with the "resect and discard" policy.METHODS: Patients who received colonoscopy and polypectomy were recruited in the retrospective study. Probable histology of the polyps was predicted by six colonoscopists by the use of NICE classification. The incidence of diminutive and small colorectal cancersand their endoscopic features were assessed. RESULTS: In total, we found 681 cases of diminutive(1-5 mm) lesions in 402 patients and 197 cases of small(6-9 mm) lesions in 151 patients. Based on pathology of the diminutive and small polyps, 105 and 18 were non-neoplastic polyps, 557 and 154 were low-grade adenomas, 18 and 24 were high-grade adenomas or intramucosal/submucosal(SM) scanty invasive carcinomas, 1 and 1 were SM deeply invasive carcinoma, respectively. The endoscopic features of invasive cancer were classified as NICE type 3 endoscopically.CONCLUSION: The risk of failing to detect diminutive and small colorectal invasive cancer with the "resect and discard" strategy might be avoided through the use of narrow-band imaging observation with the NICE classification scheme and magnifying endoscopy.