Kenichi Goda

Early Detection of Superficial Squamous Cell Carcinoma in the Head and Neck Region and Esophagus by Narrow Band Imaging: A Multicenter Randomized Controlled Trial

PURPOSE Most of the esophageal squamous cell carcinomas (ESCCs) and cancers of the head and neck (H&N) region are diagnosed at later stages. To achieve better survival, early detection is necessary. We compared the real-time diagnostic yield of superficial cancer in these regions between conventional white light imaging (WLI) and narrow band imaging (NBI) in high-risk patients. PATIENTS AND METHODS In a multicenter, prospective, randomized controlled trial, 320 patients with ESCC were randomly assigned to primary WLI followed by NBI (n = 162) or primary NBI followed by WLI (n = 158) in a back-to-back fashion. The primary aim was to compare the real-time detection rates of superficial cancer in the H&N region and the esophagus between WLI and NBI. The secondary aim was to evaluate the diagnostic accuracy of these techniques. RESULTS NBI detected superficial cancer more frequently than did WLI in both the H&N region and the esophagus (100% v 8%, P < .001; 97% v 55%, P < .001, respectively). The sensitivity of NBI for diagnosis of superficial cancer was 100% and 97.2% in the H&N region and the esophagus, respectively. The accuracy of NBI for diagnosis of superficial cancer was 86.7% and 88.9% in these regions, respectively. The sensitivity and accuracy were significantly higher using NBI than WLI in both regions (P < .001 and P = .02 for the H&N region; P < .001 for both measures for the esophagus, respectively). CONCLUSION NBI could be the standard examination for the early detection of superficial cancer in the H&N region and the esophagus.

Combined use of a magnifying endoscope with a narrow band imaging system and a multibending endoscope for en bloc EMR of early stage gastric cancer.

BACKGROUND En bloc EMR is performed in Japan as a curative treatment for early stage gastric cancer. However, current methods of EMR are technically difficult and require proficiency in determining the extent of the cancer. This study assessed the feasibility of a new method to obviate these problems and to facilitate en bloc EMR. METHODS The new method uses two types of endoscopes: a magnifying endoscope with a narrow band imaging system to enhance the definition of mucosal and microcirculatory structure, and an endoscope with multibending tip deflection to maintain orientation during EMR. Forty-two consecutive cases of mucosal gastric cancer treated by EMR were reviewed retrospectively. In 12 of these patients, 12 lesions that fulfilled guideline criteria for EMR were treated by the modified, en bloc EMR method of circumferential incision and snare resection by using the two endoscopes. RESULTS The rate of complete en bloc resection with the new method of EMR was 91.7%, (11/12). There was no major complication. CONCLUSIONS The new en bloc resection method for EMR with two endoscopes described here is feasible and may be a safe and a reliable technique for curative treatment of mucosal gastric cancer.

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

BACKGROUND AND AIM Magnifying 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). PATIENTS AND METHODS ME-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. RESULTS Multivariate 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). CONCLUSION The 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.

ROLE OF NARROW BAND IMAGING FOR DIAGNOSIS OF EARLY-STAGE ESOPHAGOGASTRIC CANCER: CURRENT CONSENSUS OF EXPERIENCED ENDOSCOPISTS IN ASIA-PACIFIC REGION

In Asian countries, squamous cell carcinoma is the most common type of esophageal cancer, and the incidence of gastric cancer remains have plateaued. To synthesize current information and to illustrate its clinical benefit of narrow band imaging (NBI) for diagnosis of superficial esophageal squamous carcinoma (SESCC) and early gastric cancer (EGC), a consensus conference was held by a panel of nine experts from Asian‐Pacific countries. The experts agreement suggested importance of interpretation of both vascular architecture and surface structure of the lesions and proper processor settings for endoscopic images. Zoom endoscopy was not regarded as absolutely necessary for detection of SESCC, but magnifying observation provided valuable information for characterization of detected lesions in the esophagus and the stomach. In general, NBI is useful for detection and characterization of SESCC, whereas it is beneficial mainly for characterization of EGC. Chromoendoscopy was found to be still worthwhile in certain situations, such as determination of the extent of SESCC by Lugols staining, or detection and delineation of EGC by indigo carmine. NBI could replace chromoendoscopy in routine examination because it is easy to use and adds much information to conventional WLI, but it cannot eliminate chromoendoscopy when we make a final diagnosis for treatment decision‐making. Consequently, the benefit of NBI or magnifying NBI is specific for the organ and the purpose of the examination, thus optimum indication and usage should be understood for maximum clinical benefit.

New approach to diagnosing ampullary tumors by magnifying endoscopy combined with a narrow-band imaging system

BackgroundA newly developed narrow-band imaging (NBI) system, which uses modified optical filters, can yield clear images of microvessels and surface structure in gastric and colonic diseases. In the present study, we investigated the ability of magnifying endoscopy with NBI (MENBI) to diagnose and differentiate between benign and malignant ampullary tumors.MethodsFourteen patients, whose ampullas were noted to be significantly enlarged or protruding with conventional endoscopy, were enrolled in the study. Specimens, which were obtained by forceps biopsy, endoscopic papillectomy, and/or surgery, were retrieved for histopathological examination. The correlation between MENBI images and histopathological findings was investigated. MENBI findings were classified as I, oval-shaped villi; II, pinecone/leaf-shaped villi; or III, irregular/nonstructured. In addition, tortuous, dilated, and network-like vessels noted on the ampullary lesions with MENBI were defined as abnormal vessels.ResultsIn 6 of 14 patients, the ampullary changes were proven to be inflammatory in forceps biopsy specimens, without any evidence of malignancy after more than 1 year of follow-up. In five patients, ampullary lesions were treated by endoscopic papillectomy, and in three, by pancreatoduodenectomy. All adenomas and adenocarcinomas had type II and/or type III surface structures, and patients whose ampulla had a type I surface structure had only inflammatory or hyperplastic changes. In addition, abnormal vessels were seen only in adenocarcinomas and never in adenomas.ConclusionsMENBI has the ability and potential to predict histological characteristics of ampullary lesions.

Development and Validation of a Classification System to Identify High-Grade Dysplasia and Esophageal Adenocarcinoma in Barrett's Esophagus Using Narrow-Band Imaging

BACKGROUND & AIMS Although several classification systems have been proposed for characterization of Barretts esophagus (BE) surface patterns based on narrow-band imaging (NBI), none have been widely accepted. The Barretts International NBI Group (BING) aimed to develop and validate an NBI classification system for identification of dysplasia and cancer in patients with BE. METHODS The BING working group, composed of NBI experts from the United States, Europe, and Japan, met to develop a validated, consensus-driven NBI classification system for identifying dysplasia and cancer in BE. The group reviewed 60 NBI images of nondysplastic BE, high-grade dysplasia, and esophageal adenocarcinoma to characterize mucosal and vascular patterns visible by NBI; these features were used to develop the BING criteria. We then recruited adult patients undergoing surveillance or endoscopic treatment for BE at 4 institutions in the United States and Europe, obtaining high-quality NBI images and performing histologic analysis of biopsies. Experts individually reviewed 50 NBI images to validate the BING criteria, and then evaluated 120 additional NBI images (not previously viewed) to determine whether the criteria accurately predicted the histology results. RESULTS The BING criteria identified patients with dysplasia with 85% overall accuracy, 80% sensitivity, 88% specificity, 81% positive predictive value, and 88% negative predictive value. When dysplasia was identified with a high level of confidence, these values were 92%, 91%, 93%, 89%, and 95%, respectively. The overall strength of inter-observer agreement was substantial (κ = 0.681). CONCLUSIONS The BING working group developed a simple, internally validated system to identify dysplasia and EAC in patients with BE based on NBI results. When images are assessed with a high degree of confidence, the system can classify BE with >90% accuracy and a high level of inter-observer agreement.

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

BACKGROUND A considerable number of superficial gastric neoplasias are overlooked with conventional white light imaging (WLI) endoscopy. OBJECTIVE The 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. DESIGN Feasibility study. SETTING Single academic center. PATIENTS Sixty-two patients with or without gastric neoplasia. INTERVENTION Each 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. MAIN OUTCOME MEASUREMENTS Sensitivity and specificity of endoscopic diagnosis of pathology-proven neoplasia by per-patient and per-lesion analyses. RESULTS The 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%). LIMITATIONS Case-enriched population at a single center. CONCLUSIONS Higher diagnostic accuracy of TME over conventional WLI indicates the feasibility of TME for the efficacious diagnosis of early gastric neoplasia.

Endoscopic assessment and grading of Barrett's esophagus using magnification endoscopy and narrow-band imaging: accuracy and interobserver agreement of different classification systems (with videos)

BACKGROUND Three different classification systems for the evaluation of Barretts esophagus (BE) using magnification endoscopy (ME) and narrow-band imaging (NBI) have been proposed. Until now, no comparative and external evaluation of these systems in a clinical-like situation has been performed. OBJECTIVE To compare and validate these 3 classification systems. DESIGN Prospective validation study. SETTING Tertiary-care referral center. Nine endoscopists with different levels of expertise from Europe and Japan participated as assessors. PATIENTS Thirty-two patients with long-segment BE. INTERVENTIONS From a group of 209 standardized prospective recordings collected on BE by using ME combined with NBI, 84 high-quality videos were randomly selected for evaluation. Histologically, 28 were classified as gastric type mucosa, 29 as specialized intestinal metaplasia (SIM), and 27 as SIM with dysplasia/cancer. Assessors were blinded to underlying histology and scored each video according to the respective classification system. Before evaluation, an educational set concerning each classification system was carefully studied. At each assessment, the same 84 videos were displayed, but in different and random order. MAIN OUTCOME MEASUREMENTS Accuracy for detection of nondysplastic and dysplastic SIM. Interobserver agreement related to each classification. RESULTS The median time for video evaluation was 25 seconds (interquartile range 20-39 seconds) and was longer with the Amsterdam classification (P < .001). In 65% to 69% of the videos, assessors described certainty about the histology prediction. The global accuracy was 46% and 47% using the Nottingham and Kansas classifications, respectively, and 51% with the Amsterdam classification. The accuracy for nondysplastic SIM identification ranged between 57% (Kansas and Nottingham) and 63% (Amsterdam). Accuracy for dysplastic tissue was 75%, irrespective of the classification system and assessor expertise level. Interobserver agreement ranged from fair (Nottingham, κ = 0.34) to moderate (Amsterdam and Kansas, κ = 0.47 and 0.44, respectively). LIMITATION No per-patient analysis. CONCLUSIONS All of the available classification systems could be used in a clinical-like environment, but with inadequate interobserver agreement. All classification systems based on combined ME and NBI, revealed substantial limitations in predicting nondysplastic and dysplastic BE when assessed externally. This technique cannot, as yet, replace random biopsies for histopathological analysis.

Endoscopic diagnosis of superficial non‐ampullary duodenal epithelial tumors in Japan: Multicenter case series

To verify the current status in Japan on endoscopic diagnosis of superficial non‐ampullary duodenal epithelial tumors (SNADET) by a multicenter case series through a questionnaire survey.