Noboru Yoshimura

Magnifying endoscopy combined with narrow-band imaging for differential diagnosis of superficial depressed gastric lesions

BACKGROUND AND AIMnMagnifying endoscopy combined with narrow-band imaging (ME-NBI) has been used for differential diagnosis of various focal lesions. The aim of our study was to evaluate ME-NBI criteria for cancer diagnosis in superficial depressed gastric lesions in comparison to conventional white light endoscopy (WLE).nnnPATIENTS AND METHODSnME-NBI and WLE images of 100 superficial gastric depressions (55 depressed cancers, 45 benign depressions) were independently evaluated by 11 endoscopists blinded to the diagnosis in each case. The presence or absence of predefined ME-NBI findings relating to microvasculature and fine mucosal structure (FMS) was recorded. A general diagnosis of benign or malignant also had to be given on the basis of a general assessment of features of color and shape as shown in the ME-NBI and WLE images, respectively, without regard to any prespecified criteria.nnnRESULTSnMultivariate and ROC analysis demonstrated that the triad of FMS disappearance, microvascular dilation, and heterogeneity appeared to be the best combination for diagnosis of gastric cancer. ME-NBI diagnosis with the triad attained a good specificity (85 %, theoretically calculated if all of the triad were positive), which was significantly ( P < 0.001) superior to WLE general diagnosis (65 %), and comparable with ME-NBI general diagnosis (80 %). The sensitivities of the three diagnoses (ME-NBI with the triad 69 %, WLE general diagnosis 71 %, ME-NBI general diagnosis 72 %) were comparably moderate. The kappa values (interobserver concordance) for ME-NBI diagnosis with the triad (0.47) and ME-NBI general diagnosis (0.48) were superior to the kappa value for WLE diagnosis (0.34).nnnCONCLUSIONnThe triad of FMS disappearance, microvascular dilation, and heterogeneity has good specificity for the diagnosis of superficial depressed gastric carcinoma, but the sensitivity needs to be improved.

Magnifying endoscopy with narrow-band imaging achieves superior accuracy in the differential diagnosis of superficial gastric lesions identified with white-light endoscopy: a prospective study

BACKGROUNDnConventional, white-light imaging endoscopy (WLE) results in a significant number of misdiagnoses in early gastric cancer. Magnifying endoscopy combined with narrow-band imaging (ME-NBI) is more accurate in the diagnosis of gastric cancer when the diagnostic triad of the disappearance of fine mucosal structure, microvascular dilation, and heterogeneity is used.nnnOBJECTIVEnThe aim of the present study was to evaluate the superiority of ME-NBI in the differential diagnosis of superficial gastric lesions identified with conventional WLE.nnnDESIGNnProspective, comparative study.nnnSETTINGnSingle academic center.nnnPATIENTSnThis study involved patients who underwent WLE and ME-NBI for surveying synchronous or metachronous cancers because they had a high risk of gastric cancer.nnnINTERVENTIONnPatients with superficial gastric lesions that were diagnosed by WLE as cancer or non-cancer with a slight suspicion of cancer were prospectively enrolled in the study. ME-NBI was used to further characterize lesions picked up with WLE.nnnMAIN OUTCOME MEASUREMENTSnSensitivity and specificity for the diagnosis of gastric cancer, with pathology as the criterion standard.nnnRESULTSnA total of 201 lesions (mean diameter [+/- SD] 7.0 +/- 4.0 mm) from 111 patients (98 men, 13 women; mean age 66.3 years) were evaluated. Fourteen of the 201 lesions were pathologically proven as gastric cancer; the others were noncancerous lesions. The sensitivity and specificity for ME-NBI diagnosis with the use of the triad (92.9% and 94.7%, respectively) were significantly better than for WLE (42.9% and 61.0%, respectively; P < .0001).nnnLIMITATIONSnSingle center and a highly selected population at high risk for gastric cancer.nnnCONCLUSIONnME-NBI achieved superior accuracy in the differential diagnosis of superficial gastric lesions identified with WLE. Thus, ME-NBI may increase the diagnostic value of endoscopy in a population at high risk of gastric cancer.

Magnifying endoscopy with narrow band imaging for predicting the invasion depth of superficial esophageal squamous cell carcinoma

The invasion depth of superficial esophageal squamous cell carcinoma is important in determining therapeutic strategy. The aim of this study was to prospectively investigate the clinical utility of magnifying endoscopy with narrow band imaging compared with that of non-magnifying high-resolution endoscopy or high-frequency endoscopic ultrasonography in predicting the depth of superficial esophageal squamous cell carcinoma. The techniques were carried out in 72 patients with 101 superficial esophageal squamous cell carcinomas, which were then resected by either endoscopic mucosal resection or esophagectomy. The histological invasion depth was divided into two: mucosal or submucosal carcinoma. We investigated the relationship between endoscopic staging and histology of tumor depth. Non-magnifying high-resolution endoscopy, magnifying endoscopy with narrow band imaging, and high-frequency endoscopic ultrasonography had overestimation/underestimation rates of 7/5, 4/4 and 8/3%, respectively. The sensitivity rates for the three techniques were 72, 78, and 83%, respectively, and the specificity rates were 92, 95, and 89%, respectively. There were no statistically significant differences among the three endoscopic techniques. Clinical utility of magnifying endoscopy with narrow band imaging does not seem to be significantly different from that of non-magnifying high-resolution endoscopy or high-frequency endoscopic ultrasonography in predicting the depth of superficial esophageal squamous cell carcinoma. Magnifying endoscopy with narrow band imaging may have potential to reduce overestimation risks of non-magnifying high-resolution endoscopy or high-frequency endoscopic ultrasonography.

Trimodal imaging endoscopy may improve diagnostic accuracy of early gastric neoplasia: a feasibility study

BACKGROUNDnA considerable number of superficial gastric neoplasias are overlooked with conventional white light imaging (WLI) endoscopy.nnnOBJECTIVEnThe aim was to investigate the diagnostic potential of trimodal imaging endoscopy (TME), which combines WLI, autofluorescence imaging (AFI), and narrow-band imaging (NBI), for superficial gastric neoplasia.nnnDESIGNnFeasibility study.nnnSETTINGnSingle academic center.nnnPATIENTSnSixty-two patients with or without gastric neoplasia.nnnINTERVENTIONnEach patient serially assessed with WLI, AFI, and magnifying endoscopy with NBI (ME-NBI) by an endoscopist blinded for clinical information. ME-NBI over WLI and AFI was designated as TME. Histopathology of biopsy and ESD specimens was evaluated and used as the gold standard.nnnMAIN OUTCOME MEASUREMENTSnSensitivity and specificity of endoscopic diagnosis of pathology-proven neoplasia by per-patient and per-lesion analyses.nnnRESULTSnThe study included 47 pathology-proven neoplasias and 44 pathology-proven nonneoplasias that were detected as neoplasias with any of the modalities. By a per-lesion analysis, the sensitivity of TME (89.4%) was higher than that of WLI (76.6%) and AFI (68.1%). The specificity of TME (98.0%) was higher than that of WLI (84.3%) and AFI (23.5%). By a per-patient analysis, the sensitivity of TME (90.9%) was higher than that of WLI (75%) and AFI (68.2%). The specificity of TME (100%) was higher than that of WLI (72.2%) and AFI (44.4%).nnnLIMITATIONSnCase-enriched population at a single center.nnnCONCLUSIONSnHigher diagnostic accuracy of TME over conventional WLI indicates the feasibility of TME for the efficacious diagnosis of early gastric neoplasia.

Assessment of novel endoscopic techniques for visualizing superficial esophageal squamous cell carcinoma: autofluorescence and narrow-band imaging

Lugol chromoendoscopy (LCE) is a useful technique for visualizing superficial esophageal squamous cell carcinoma (SESCC), but the stimulating effect of the Lugol solution can sometimes cause clinical problems. Newly developed techniques such as narrow-band imaging (NBI) and autofluorescence imaging (AFI) enable SESCC to be easily visualized without LCE. This study aimed to assess the visualizing power of white-light imaging (WLI), NBI, and AFI, compared with LCE. Sixteen patients with 16 SESCCs underwent LCE and endoscopy with NBI and AFI before endoscopic or surgical treatment. Twenty sets of endoscopic SESCC images were prepared, each of which contained still images from WLI, NBI, AFI, and LCE. The image sets were shown to 25 endoscopists, who then each completed a questionnaire about the ease-of-detection of the SESCCs, scoring WLI, NBI, and AFI images with reference to a perfect score for LCE; mean scores were compared. Overall, significantly higher scores were given for NBI than for WLI and AFI, with no significant difference between WLI and AFI. Stratification by endoscopist characteristics indicated that younger or less experienced endoscopists gave significantly higher scores for AFI than WLI. Stratification by lesion characteristics revealed that AFI had significantly higher scores than WLI for flat/elevated lesions or those with diameter >or=20 mm; scores were significantly lower for depressed lesions or those with diameter <20 mm. For SESCC, the visualizing power of NBI seems more similar to that of LCE than AFI or WLI: NBI might be more useful than AFI or WLI in detecting SESCC. AFI seems to have both superior and inferior visualizing power to WLI depending on characteristics of endoscopists or SESCC lesions.

Ultrathin endoscopy versus high-resolution endoscopy for diagnosing superficial gastric neoplasia

BACKGROUNDnUltrathin endoscopy (UTE) is an acceptable and cost-effective alternative to EGD with the patient under sedation, although the diagnostic accuracy of UTE is not well established.nnnOBJECTIVEnTo compare the diagnostic accuracy of UTE and high-resolution endoscopy (HRE) for superficial gastric neoplasia.nnnDESIGNnProspective comparative study.nnnSETTINGnAcademic center.nnnPATIENTS AND INTERVENTIONSnPatients with or without superficial gastric neoplasia underwent peroral UTE and HRE, back-to-back in a random order while under standard sedation. The procedures were performed by 2 endoscopists who were blinded to the clinical information.nnnMAIN OUTCOME MEASUREMENTSnThe rate of missed lesions and misdiagnosis, sensitivity, and specificity for the diagnosis of gastric neoplasia when using pathology as the reference standard.nnnRESULTSnIn total, 126 lesions (41 superficial gastric neoplasias, 85 nonneoplastic lesions) were recorded in 57 enrolled patients. For the diagnosis of gastric neoplasia, the sensitivity of UTE (58.5%) was significantly (P = .021) lower than that of HRE (78%), and the specificity of UTE (91.8%) was significantly (P = .014) lower than that of HRE (100%). The rate of missed lesions and misdiagnosis of gastric neoplasias when using UTE (41.5%) was significantly (P > .001) higher than that of HRE (22.0%). The corresponding rate of neoplasias at the proximal portion (fornix and corpus) when using UTE (29%) was significantly (P = .002) higher than that of HRE (7.2%), although the rates of neoplasias at the distal portion (angulus and antrum) were comparable for UTE and HRE.nnnLIMITATIONnSmall sample numbers in an enriched population.nnnCONCLUSIONSnThe diagnostic accuracy of UTE is significantly lower than that of HRE for superficial gastric neoplasia, and this difference is particularly striking for neoplasias in the proximal stomach. For UTE to be used as an alternative modality, improvements in optical quality and the incorporation of additional procedures, including close-range observations and chromoendoscopy, are required to enhance visualization.

Diagnostic utility of narrow-band imaging endoscopy for pharyngeal superficial carcinoma.

AIMnTo investigate the endoscopic features of pharyngeal superficial carcinoma and evaluate the utility of narrow-band imaging (NBI) for this disease.nnnMETHODSnIn the present prospective study, 335 patients underwent conventional white light (CWL) endoscopy and non-magnified/magnified NBI endoscopy, followed by an endoscopic biopsy, for 445 superficial lesions in the oropharynx and hypopharynx. The macroscopic appearance of superficial lesions was categorized as either elevated (< 5 mm in height), flat, or depressed (not ulcerous). Superficial carcinoma (SC) was defined as a superficial 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-magnified/magnified NBI endoscopy. An experienced pathologist who was unaware of the endoscopic findings made the histological diagnoses. By comparing endoscopic findings with histology, we determined the endoscopic features of SC and evaluated the diagnostic utility of NBI.nnnRESULTSnThe 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 classified 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 significantly 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 findings 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-magnified NBI endoscopy, the incidence of a brownish area was significantly higher for SC lesions (79% vs 57%, respectively, P < 0.001). On magnified 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 significantly 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 magnified NBI endoscopy was significantly higher in SC than non-SC lesions. Redness alone exhibited significantly higher sensitivity and significantly lower specificity 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 significantly greater than using redness alone (82% vs 62%, respectively, P < 0.001).nnnCONCLUSIONnRedness, IBE, and microvascular irregularities appear to be closely related to SC lesions. Magnified NBI endoscopy may increase the diagnostic accuracy of CWL endoscopy for SC.

Narrow-Band Imaging Magnifying Endoscopy versus Lugol Chromoendoscopy with Pink-Color Sign Assessment in the Diagnosis of Superficial Esophageal Squamous Neoplasms: A Randomised Noninferiority Trial

Previous studies have shown the high diagnostic accuracy of narrow-band imaging magnifying endoscopy (NBI-ME) and Lugol chromoendoscopy with pink-color sign assessment (LCE-PS) for superficial esophageal squamous cell carcinoma (SESCC). However, there has been no controlled trial comparing these two diagnostic techniques. We conducted a randomized noninferiority trial to compare the diagnostic accuracy of NBI-ME and LCE-PS. We recruited patients with, or with a history of, squamous cell carcinoma in the head and neck region or in the esophagus. They were randomly assigned to either NBI-ME or LCE-PS. When lesions > 5u2009mm in diameter were found as brownish areas on NBI or as Lugol-voiding lesions (LVL), they were evaluated to determine whether they are SESCC on the basis of the findings of NBI-ME or PS in the LVL. NBI-ME and LCE-PS were completed in 147 patients each. There was no significant difference in all diagnostic values between the two techniques. Compared with LCE-PS, NBI-ME showed a significantly shorter examination time but a larger number of misdiagnosed lesions especially in patients with many irregularly shaped multiform LVLs. Compared with LCE-PS, NBI-ME might be similarly accurate and less invasive, but less reliable in patients with many LVLs, in the diagnosis of SESCC.

Bacteremia and endotoxemia after endoscopic submucosal dissection for gastric neoplasia: pilot study

BackgroundBecause the invasive procedure of endoscopic submucosal dissection (ESD) entails a large mucosal defect which is left open, with extensive submucosal exposure to the indigenous bacterial flora, the procedure may have a substantial risk for bacteremia. Our aim was to examine gastric ESD-related bacteremia and endotoxemia in gastric neoplasia patients.MethodsIn patients who underwent ESD for superficial gastric neoplasia, blood cultures and plasma endotoxin measurements were done before, immediately after, and on day 2 after ESD. Clinically manifest infections and inflammatory markers, including C-reactive protein (CRP) and white blood cells, were monitored.ResultsFifty patients (aged 69xa0±xa08xa0years; mean ± SD) were enrolled. The diameter of the resected specimens was 38xa0±xa018xa0mm and the procedure time of ESD was 66xa0±xa053xa0min. Two percent (2/100) of blood cultures after ESD were positive, with findings as follows: Propionibacterium species immediately after ESD, and Enterobacter aerogenes on day 2 after ESD, but no clinically manifest infection was observed. In 30% of the enrolled patients, CRP on day 2 after ESD had increased to levels higher than 1.0xa0mg/l. Plasma endotoxin levels, immediately after and on day 2 after ESD were correlated with CRP levels on day 2 after ESD.ConclusionsIn spite of the invasive procedure with massive submucosal exposure to the indigenous bacterial flora, gastric ESD has a low risk for bacteremia. Gastric ESD-related endotoxemia may be linked to inflammatory reactions such as those shown by the increase of CRP or fever observed after ESD.

CLINICAL IMPACT OF NARROW-BAND IMAGING MAGNIFYING ENDOSCOPY FOR ‘BASAL LAYER TYPE SQUAMOUS CELL CARCINOMA’ IN THE ESOPHAGUS

A 61‐year‐old man had received endoscopic submucosal dissection (ESD) for early gastric cancer twice. Then he had undergone annual control esophagogastroduodenoscopy using narrow‐band imaging (NBI) magnifying endoscope. At the esophagogastroduodenoscopy, we were not able to detect any significant finding in the esophagus by conventional endoscopy. Switching to NBI mode, a brownish area was showed in the middle esophagus. The lesion showing the brownish area was predicted to be mucosal squamous cell carcinoma (SCC) as a result of assessment of morphologic change of intraepithelial papillary capillary loop under magnifying NBI observation. Lugol chromoendoscopy displayed the lesion as unstained area corresponding to the brownish area visualized by NBI. The ESD was performed for the lesion. Histology from ESD specimen showed SCC with minimal invasion to lamina propria at multifocal sites. The SCC was surrounded by low‐grade intraepithelial neoplasia. Most of the SCC showed a high degree of cytological and architectural atypia confined to the lower half of the epithelium. The type of SCC was called as ‘basal layer type SCC’ mainly by Japanese pathologists. We suggest that magnifying NBI endoscopy can be useful for detecting and diagnosing ‘basal layer type SCC’.