Bimodal Chromoendoscopy with Confocal Laser Endomicroscopy for the Detection of Early Esophageal Squamous Cell Neoplasms

Background/Aims This study aimed to evaluate the diagnostic accuracy of dual-focus narrow-band imaging (dNBI) and Lugol’schromoendoscopy (LCE) combined with probe-based confocal laser endomicroscopy (pCLE) to screen for esophageal squamous cell neoplasms (ESCNs) in patients with a history of head and neck cancer. Methods From March to August 2016, dNBI was performed. Next, LCE was performed, followed by pCLE and biopsy. Histology has historically been the gold standard to diagnose ESCN. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of dNBI and LCE adjunct with pCLE were determined. Results Twenty-four patients were included. Ten ESCNs were found in 8 patients (33%). Forty percent of high-graded intraepithelial neoplasias and all low-grade intraepithelial neoplasias were overlooked by dNBI. The sensitivity, specificity, PPV, NPV, and accuracy of dNBI vs. LCE combined with pCLE were 50% vs. 80%, 62% vs. 67%, 36% vs. 44%, 75% vs. 91%, and 83% vs. 70%, respectively. Conclusions The use of dNBI to detect ESCN was suboptimal. LCE with pCLE following dNBI had additional value for detecting esophageal dysplasia not detected by dNBI. The use of pCLE to detect dNBI-missed lesions yielded a high NPV, while pCLE-guided biopsy could reduce the number of unnecessary biopsies

Real-time semantic segmentation of gastric intestinal metaplasia using a deep learning approach

Background/Aims Previous artificial intelligence (AI) models attempting to segment gastric intestinal metaplasia (GIM) areas have failed to be deployed in real-time endoscopy due to their slow inference speeds. Here, we propose a new GIM segmentation AI model with inference speeds faster than 25 frames per second that maintains a high level of accuracy. Methods Investigators from Chulalongkorn University obtained 802 histological-proven GIM images for AI model training. Four strategies were proposed to improve the model accuracy. First, transfer learning was employed to the public colon datasets. Second, an image preprocessing technique contrast-limited adaptive histogram equalization was employed to produce clearer GIM areas. Third, data augmentation was applied for a more robust model. Lastly, the bilateral segmentation network model was applied to segment GIM areas in real time. The results were analyzed using different validity values. Results From the internal test, our AI model achieved an inference speed of 31.53 frames per second. GIM detection showed sensitivity, specificity, positive predictive, negative predictive, accuracy, and mean intersection over union in GIM segmentation values of 93%, 80%, 82%, 92%, 87%, and 57%, respectively. Conclusions The bilateral segmentation network combined with transfer learning, contrast-limited adaptive histogram equalization, and data augmentation can provide high sensitivity and good accuracy for GIM detection and segmentation

Smart Atlas for Supporting the Interpretation of probe-based Confocal Laser Endomicroscopy (pCLE) of Gastric Lesions: First Classification Results of a Computer-Aided Diagnosis Software based on Image Recognition

International audiencepCLE enables microscopic imaging of gastrointestinal mucosal lesions, in vivo and in real time, during an endoscopy procedure. Recent studies have demonstrated that pCLE enables accurate diagnosis of superfcial gastric neoplasia. In parallel, a computer-aided diagnosis software called Smart Atlas has been developed to assist endoscopists with the interpretation of pCLE sequences. This study aims at evaluating the performance of this software for the classifcation of gastric lesions into four pathological classes: healthy stomach, gastric intestinal metaplasia (GIM), dysplasia, and cancer

Prognostic factor affecting outcomes in patients with malignant gastrointestinal bleeding treated with a novel endoscopically-delivered hemostatic powder

Prognostic factor affecting outcomes in patients with malignant gastrointestinal bleeding treated with a novel endoscopically-delivered hemostatic powderAbstractBackground and study aim: The effectiveness of endoscopic hemostatic technique for gastrointestinal (GI) tumor bleeding remains poor. HemosprayTM appears useful in many active GI bleeding etiologies, including tumor bleeding. This study aims to define factors predicting decreased rebleeding and improved six-month survival in affected patients. Materials and Methods: This is a retrospective study. Ninety-nine patients with active GI bleeding from primary or metastatic tumors to the digestive tract and treated with HemosprayTM were enrolled. Eleven patients were excluded because of incomplete data. Appropriate data on patient characteristics and possible predictive factors of 72-hour, 7, 14 and 30-day re-bleeding rates, as well as six-month survival were assessed. Results: The majority of patients were male (62/88; 70.5%) with a mean age at 65 ±14 years. Half of patients (43/88) had high ECOG performance status (score 3 or 4). An upper GI cancer was found in nearly 60 percent (50/88), followed by hepatobiliary cancers invading the upper GI tract (17/88; 19%), distant metastases to the upper GI tract (12/88; 14%), and lower GI cancers (9/88;10%). Three-fourths of patients' cancers (64/88) were stage 4, with an overall 55% (48/88) six-month survival. Immediate hemostasis by using HemospayTM was achieved in 97.7% of patients with malignant active GI bleeding. Early (<72 hr) and delayed (7, 14 and 30 days) rebleeding were noted in 13 of 86 (15%) and 11 of 63 (17%) patients, respectively. In univariable analysis, INR >1.3(38% vs.11%) was significantly associated with early re-bleeding, while an ECOG 3-4 (30% vs. 10%) and not receiving definite hemostatic treatment (39% vs. 9%) were with delayed rebleeding. Comorbidity with another type of cancer vs. no comorbidity (28.6%vs.58.6%), a low ECOG score 0-2 vs. 3-4 (91.1%vs.16.3%), primary upper and lower GI cancer/lymphoma vs. distant metastases to the upper GI tract (62% and 77.8%, respectively vs.25%), disease staging 1-3 vs. 4 (87.5% vs. 42.2%), and receiving definite hemostatic treatment vs. none (82.7% vs. 13.9%) were all significantly predictive of six-month survival. In multivariable analysis, receiving definite hemostastic treatment with any combination of surgery/ chemotherapy/ radiotherapy/ embolization was the only significant predictor of delayed rebleeding (p=0.04, OR=0.06, 95%CI 0.01-0.84) and of six-month survival (p=0.002, HR=0.21, 95%CI 0.08-0.57) after adjusting for comorbidity, performance status, type of cancer bleeding and cancer stage. Conclusions: HemosprayTM is a promising therapy for the initial hemostasis of tumoral GI bleeding as it can stop bleeding acutely in a great majority of cases, and appears to do so for at least the first few days. Definite hemostatic treatment with any combination of modalities is the sole identified independent predictor of delayed rebleeding and six-month survival, regardless of performance status or other patient-dependent variables such as cancer type and staging.Facteurs pronostics influencant le devenir des patients avec une hemorragie digestive maligne ayant ete traites avec une nouvelle poudre hemostatique appliquee par voie ndoscopiqueAbstractToile de fond et objectifs: L'efficacité des méthodes endoscopiques hémostatiques pour saignements malins demeure limitée. L'Hemospray® apparait utile pour les saignements digestifs de maintes étiologies, y compris les causes malignes. Cette étude a pour objectif de définir les facteurs prédisant une diminution des taux de resaignement et une amélioration de la survie à 6 mois. Méthodes: Cette étude rétrospective comprend 99 patients présentant une hémorragie digestive active due à une tumeur primaire ou métastatique ayant été traités par Hemospray®. Onze patients furent exclus pour cause de données manquantes. Nous avons évalué les données pertinentes des caractéristiques de patients et facteurs prédisant les resaignements à72 heures, 7, 14, et 30 jours ainsi que les taux de survie à 6 mois. Résultats: La majorité des patients étaient males (62/88; 70.5%) avec un âge moyen de 65 ±14 ans. La moitié des patients (43/88) présentaient un indice ECOG de performance élevé (scores 3 ou 4). Un cancer du tractus digestif supérieur a été noté chez presque 60 pourcent (50/88) des patients, suivi d'un cancer hepatobiliaire affectant le tractus digestif supérieur (17/88; 19%), des métastases distantes affectant le tractus digestif supérieur (12/88; 14%), et de cancers digestifs des voies basses (9/88;10%). Trois-quarts des cancers (64/88) étaient de stade 4, avec une survie globale de 55% (48/88) à 6 mois. Une hémostase immédiate fut notée avec l' Hemospray® chez 97.7%. Des resaignements précoces (<72 hres) ou à retardement (7, 14 et 30 jours) furent notés chez 13 de 86 (15%) et 11 de 63 (17%) patients, respectivement. En analyse univariée, l'INR >1.3 (38% vs.11%) était significativement associé à un resaignement précoce alors qu'un score ECOG 3-4 (30% vs. 10%) et l'absence de traitement hémostatique subséquent (39% vs. 9%) l'étaient avec les saignements à retardement. Une comorbidité d'un autre cancer vs. aucune (28.6%vs.58.6%), un score ECOG bas 0-2 vs. 3-4 (91.1% vs.16.3%), une tumeur primaire des tractus digestifs hauts et bas/lymphomes vs. métastases distantes au tractus digestif supérieur (62% and 77.8%, respectivement vs. 25%), stade de cancer 1-3 vs. 4 (87.5% vs. 42.2%), et recevoir un traitement hémostatique définitif vs. aucun (82.7% vs. 13.9%) tous prédirent la survie à 6 mois de façon significative. En analyse multivariée, un traitement hémostatique définitif avec toute combinaison de chirurgie/ chimiothérapie/ radiothérapie/ embolisation était le seul facteur prédictif significatif d'un saignement à retardement (p=0.04, OR=0.06, 95%IC 0.01-0.84) et de survie a 6 mois (p=0.002, HR=0.21, 95%IC 0.08-0.57) après ajustement pour comorbidité, score de performance, type de cancer hémorragique et stade de cancer. Conclusions: L'HemosprayTM est une thérapie prometteuse pour l'hémostase initiale de tumeurs digestives hémorragiques car ce produit permet de mettre fin au saignement en phase aigüe chez la majorité des patients, et semble accomplir ceci pour les quelques premiers jours. Un traitement hémostatique définitif avec toute combinaison de modalités est le seul facteur prédictif d'un resaignement à retardement et de survie à 6 mois, indépendamment du stage de performance ou de toute autre caractéristique démographique, y compris le type et le stade du cancer

Endoscopic ultrasound-guided needle-based confocal laser endomicroscopy for diagnosis of solid pancreatic lesions

An accurate diagnosis of solid pancreatic lesions (SPLs) is important because pancreatic cancer cannot be ignored if curative treatment is possible. Prompt and reliable diagnostic procedures are greatly needed for patients presenting with SPLs, particularly where resection is possible for a malignant mass. Several endoscopic ultrasound (EUS)-related technologies including a novel EUS-guided needle-based confocal laser endomicroscopy (EUS-nCLE) can provide real-time images at the cellular level (1,000-fold magnification). A 19-gauge EUS-guided fine needle aspiration (EUS-FNA) needle is recommended because its channel is large enough for the 0.85-mm diameter nCLE miniprobe. The procedure is performed by standard EUS-FNA techniques with either pre- or post-loading technique. Ten percent fluorescein sodium (2.5–5 mL) is used as an enhancing agent and is intravenously injected immediately before puncturing the lesion. Only a few studies have used the technique and reported results. A recent study from 19 malignant and 3 benign SPLs classified EUS-nCLE findings according to 4 signs: dark clumps, and dilated vessels (predominantly seen in malignant SPLs) and fine white fibrous bands and normal acini (predominantly seen in benign SPLs). Using these criteria, researchers correctly diagnosed 18 of the malignant SPLs (94.7%). Another study described 2 lesions as having “dark cells aggregates with pseudo-glandular aspects, and straight hyperdense elements more or less thick corresponding to tumoral fibrosis” in 17 of 18 malignant SPLs. Thus far, no large and systematic study has been performed to evaluate the potential clinical use of EUS-nCLE for diagnosing SPLs. However, based on available information from a few studies and the current limitations of EUS-FNA, EUS-nCLE can potentially provide a complementary role in diagnosing such lesions. Nevertheless, more studies are certainly needed

Flexible Spectral Imaging Color Enhancement and Probe-based Confocal Laser Endomicroscopy in Minimal Change Esophageal Reflux Disease

Background : /Aims: Although flexible spectral imaging color enhancement (FICE) can facilitate the diagnosis of minimal change esophageal reflux disease (MERD), the complicated diagnostic criteria cause suboptimal inter-observer agreement. Confocal laser endomicroscopy (CLE) yields good diagnostic results but its inter-observer agreement has never been explored. This study compares the diagnostic value of magnifying FICE and probe-based CLE (pCLE) for MERD and evaluates the inter-observer agreement of both techniques. Methods : : Thirty-six patients with suspected MERD and 18 asymptomatic controls were recruited. Magnifying FICE was used for evaluation of distal esophagus. pCLE counted the number of intrapapillary capillary loops (IPCLs) using more than five IPCLs in 500×500 micron area as a criterion for MERD diagnosis. The validity scores and interobserever agreement of both FICE and pCLE were assessed. Results : : For FICE vs. pCLE, the accuracy was 79% vs. 87%, sensitivity 94% vs. 97%, specificity 50% vs. 66%, positive predictive value 79% vs. 85%, and negative predictive value 82% vs. 92%. Interobserver agreement of FICE was fair to substantial, whereas pCLE had substantial to almost perfect agreement. Conclusion : s: Both FICE and pCLE have good operating characteristics and can facilitate the MERD diagnosis. However, among different observers, pCLE is more consistent on MERD diagnosis. (Korean J Gastroenterol 2016;68:29-35

Factors associated with high mortality of gastric adenocarcinoma in Thailand versus Japan

Background and aim: Thailand and Japan have high prevalence of Helicobacter pylori infection but prevalence of gastric cancer and mortality rate are difference. Most international comparative studies are epidemiologic studies and the difference in actual clinicopathological data has not been clarified. This study aimed to investigate the difference in clinicopathological characteristics of gastric adenocarcinoma between Thailand and Japan. Methods: This retrospective study was conducted in two high-volume hospitals for gastric cancer in Thailand and Japan. Baseline characteristics, clinical manifestations, tumor characteristics, treatments and mortality rate of gastric cancer patients in the two institutions were examined. Results: A total of 403 Thai and 2,318 Japanese patients were retrieved from the electronic database. Finally, 332 Thai and 414 Japanese patients (randomly sampled) with gastric adenocarcinoma were eligible for analysis. Thai gastric adenocarcinoma patients were significantly younger than the Japanese (59 ± 13 vs. 68 ±10 years old, p<0.001) and the majority of Thai patients were female (55% vs. 25%, p<0.001). The rate of smoking (5.1% vs. 23%, p<0.001) and alcohol drinking (2.7% vs. 34%, p<0.001) were lower in Thai patients when compared with those in Japanese. The mortality rate at the conclusion of this study (July 2016) was significantly higher in Thai patients (75.3% vs. 7%, p<0.001). In multivariate analysis, ethnicity, clinical UICC stage II-IV compared to I, and resection-based treatment were significant prognostic factors after adjusting for age, gender, presence of alarm symptom, lesion extension and histology. Conclusion: Thai patients with gastric adenocarcinoma were different from Japanese patients in all aspects. Advanced stage of disease, country, and un-resected tumor were associated with poor prognosis. An individual strategy to improve survival of gastric adenocarcinoma in a low-prevalence area such as Thailand should be explored

Helicobacter pylori Infection in Thailand: A Nationwide Study of the CagA Phenotype.

The risk to develop gastric cancer in Thailand is relatively low among Asian countries. In addition, the age-standardized incidence rate (ASR) of gastric cancer in Thailand varies with geographical distribution; the ASR in the North region is 3.5 times higher than that in the South region. We hypothesized that the prevalence of H. pylori infection and diversity of CagA phenotype contributes to the variety of gastric cancer risk in various regions of Thailand.We conducted a nationwide survey within Thailand. We determined H. pylori infection prevalence by detecting H. pylori, using histochemical and immunohistochemical methods. The anti-CagA antibody and anti-East-Asian type CagA antibody (α-EAS Ab), which showed high accuracy in several East Asian countries, were used to determine CagA phenotype.Among 1,546 patients from four regions, including 17 provinces, the overall prevalence of H. pylori infection was 45.9% (710/1,546). Mirroring the prevalence of H. pylori infection, histological scores were the lowest in the South region. Of the 710 H. pylori-positive patients, 93.2% (662) were immunoreactive with the anti-CagA antibody. CagA-negative strain prevalence in the South region was significantly higher than that in other regions (17.9%; 5/28; p < 0.05). Overall, only 77 patients (11.6%) were immunoreactive with the α-EAS Ab. There were no differences in the α-EAS Ab immunoreactive rate across geographical regions.This is the first study using immunohistochemistry to confirm H. pylori infections across different regions in Thailand. The prevalence of East-Asian type CagA H. pylori in Thailand was low. The low incidence of gastric cancer in Thailand may be attributed to the low prevalence of precancerous lesions. The low incidence of gastric cancer in the South region might be associated with the lower prevalence of H. pylori infection, precancerous lesions, and CagA-positive H. pylori strains, compared with that in the other regions