Narrow-band imaging for the diagnosis of nonerosive reflux disease: an international, multicenter, randomized controlled trial.

BACKGROUND AND AIMS: We examined the accuracy of narrow-band imaging (NBI) findings in nonerosive reflux disease (NERD) patients compared with control subjects and the impact of proton pump inhibitor (PPI) therapy on these mucosal changes in a multicenter, double-blind, randomized controlled trial. METHODS: NERD patients (typical symptoms using a validated GERD questionnaire, absence of erosive esophagitis, and abnormal 48-hour pH study) and control subjects underwent high-definition white-light endoscopy followed by NBI and biopsy sampling of the distal esophagus. Then, NERD patients were randomized to esomeprazole 40 mg/day or placebo for 8 weeks, followed by repeat endoscopy. The presence of distal esophageal mucosal changes on NBI were recorded at baseline and after treatment: intrapapillary capillary loops (IPCLs; number, dilation, and tortuosity), microerosions, increased vascularity, columnar islands, and ridge/villous pattern (RVP) above the squamocolumnar junction. RESULTS: Of 122 screened, 21 NERD and 21 control subjects were identified (mean age, 49.5 ± 14.6 years; 62% men; and 85% white). The combination of IPCL tortuosity, RVP, and microerosions (62% vs 19%, P < .05) had a high specificity (86%) and moderate sensitivity (60%) for NERD with an area under the curve of .74. In 10 NERD patients treated with PPIs, resolution of microerosions was most significant (P = .047) compared with placebo (n = 11). RVP resolved in all NERD patients after therapy (P = .02) and correlated with acid exposure time (P = .004). Papillary length (P = .02) and basal cell thickness (P = .02) significantly correlated with a combination of IPCL tortuosity, RVP, and microerosions. CONCLUSIONS: In this randomized controlled trial, RVP on NBI demonstrated a high specificity, correlated with acid exposure time, and improved with PPI therapy, suggesting that it could be used as a surrogate marker for diagnosis of NERD. (Clinical trial registration number: NCT02081404.).

Forkhead box F1 induces columnar phenotype and epithelial-to-mesenchymal transition in esophageal squamous cells to initiate Barrett's like metaplasia.

Multiple genome-wide association studies (GWAS) have linked Forkhead Box F1 (FOXF1) to Barrett's esophagus (BE). Understanding whether FOXF1 is involved in initiation of Barrett's metaplasia could allow FOXF1 to be used for risk stratification and for therapy. Two-dimensional cell cultures and three-dimensional organoid cultures and well-annotated human biopsies were used to determine the role of FOXF1 in BE pathogenesis. Multiple established esophageal squamous and BE cell lines were tested in gain- and loss-of-function studies. Initiation of a BE-like metaplastic change was evaluated by measuring characteristic cytokeratins and global gene expression profiling and by culturing organoids. Epithelial-mesenchymal transition (EMT) was evaluated by immunostaining for E-cadherin, vimentin and Snail, and by cell motility assay. Columnar esophageal epithelium of BE patients exhibited higher expression of FOXF1 compared to normal squamous esophageal epithelium of GERD patients (P < 0.001). Acidic bile salts induced nuclear FOXF1 in esophageal squamous cells. FOXF1 overexpression in normal esophageal squamous cells: (a) increased columnar cytokeratins and decreased squamous cytokeratins, (b) converted squamous organoids to glandular organoids, and (c) switched global gene profiles to resemble that of human BE epithelium (P = 2.1685e - 06 for upregulated genes and P = 8.3378e - 09 for downregulated genes). FOXF1 inhibition in BE cell lines led to loss of BE differentiation markers, CK7, and mucin 2. Also, FOXF1 induced EMT and promoted cell motility in normal esophageal squamous epithelial cells. FOXF1-induced genes mapped to pathways such as Cancer, Cellular Assembly and Organization, DNA Replication, Recombination, and Repair. In conclusion, FOXF1 promotes a BE-like columnar phenotype and cell motility in esophageal squamous epithelial cells, which may have a critical role in BE development. FOXF1 should be studied further as a biomarker for BE and as a target for BE treatment.

Low Risk of Progression of Barrett's Esophagus to Neoplasia in Women.

BACKGROUND AND AIMS: Men are at a higher risk for Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC), but little is known about BE progression to dysplasia and EAC in women. We performed a retrospective, multicenter cohort study to assess risk of BE progression to dysplasia and EAC in women compared with men. We also investigated comorbidities, medication use, and endoscopic features that contribute to sex differences in risk of BE progression. METHODS: We collected data from large cohort of patients with BE seen at 6 centers in the United States and Europe, followed for a median 5.7 years. We obtained demographic information (age, sex, ethnicity), clinical history (tobacco use, body mass index, comorbidities), endoscopy results (procedure date, BE segment length), and histopathology findings. Neoplasia was graded as low-grade dysplasia, high-grade dysplasia (HGD), or EAC. Rates of disease progression between women and men were compared using χ2 analysis and the Student t test. Multivariable logistic regression was used to assess the association between sex and disease progression after adjusting for possible confounding variables. RESULTS: Of the total 4263 patients in the cohort, 2145 met the inclusion criteria, including 324 (15%) women. There was a total of 34 (1.6%) incident EACs, with an overall annual incidence of 0.3% (95% confidence interval: 0.2%-0.4%). We found significant differences between women and men in annual incidence rates of EAC (0.05% for women vs. 0.3% in men; P=0.04) and in the combined endpoint of HGD or EAC (0.1% for women vs. 1.1% for men; P<0.001). Female gender was an independent predictor for reduced progression to HGD or EAC when rates of progression were adjusted for body mass index, smoking history, race, use of aspirin, nonsteroidal anti-inflammatory drugs, proton-pump inhibitors, or statins, hypertriglyceridemia, BE length, and histology findings at baseline (hazard ratio: 0.11; 95% confidence interval: 0.03-0.45; P=0.002). CONCLUSIONS: In a multicenter study of men versus women with BE, we found a significantly lower risk of disease progression to cancer and HGD in women. The extremely low risk of EAC in women with BE (0.05%/y) indicates that surveillance endoscopy may not be necessary for this subgroup of patients with BE.

Surveillance of neo-squamous epithelium after ablation of Barrett's esophagus: is it better to use jumbo over standard biopsy forceps?

BACKGROUND AND AIMS: As obtaining adequate tissue on biopsy is critical for the detection of residual and recurrent intestinal metaplasia/dysplasia in Barrett's esophagus (BE) patients undergone Barrett's endoscopic eradication therapy (BET), we decided to compare the adequacy of biopsy specimens using jumbo versus standard biopsy forceps. METHODS: This is a two-center study of patients' post-radiofrequency ablation of dysplastic BE. After BET, jumbo (Boston Scientific©, Radial Jaw 4, opening diameter 2.8 mm) or standard (Boston Scientific©, Radial Jaw 4, opening diameter 2.2 mm) biopsy forceps were utilized to obtain surveillance biopsies from the neo-squamous epithelium. Presence of lamina propria and proportion of squamous epithelium with partial or full thickness lamina propria was recorded by two experienced gastrointestinal pathologists who were blinded. Squamous epithelial biopsies that contained at least two-thirds of lamina propria were considered 'adequate'. RESULTS: In a total of 211 biopsies from 55 BE patients, 145 biopsies (29 patients, 18 males, mean age 61 years, interquartile range [IQR] 33-83) were obtained using jumbo forceps and 66 biopsies (26 patients, all males, mean age 65 years, IQR 56-76) using standard forceps biopsies. Comparing jumbo versus standard forceps, the proportion of specimens with any subepithelial lamina propria was 51.7% versus 53%, P = 0.860 and the presence of adequate subepithelial lamina propria was 17.9% versus 9.1%, P = 0.096 respectively. CONCLUSIONS: Use of jumbo forceps does not appear to have added advantage over standard forceps to obtain adequate biopsy specimens from the neo-squamous mucosa post-ablation.

Development and Validation of a Model to Determine Risk of Progression of Barrett's Esophagus to Neoplasia.

BACKGROUND & AIMS: A system is needed to determine the risk of patients with Barrett's esophagus for progression to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). We developed and validated a model to determine of progression to HGD or EAC in patients with BE, based on demographic data and endoscopic and histologic findings at the time of index endoscopy. METHODS: We performed a longitudinal study of patients with BE at 5 centers in United States and 1 center in Netherlands enrolled in the Barrett's Esophagus Study database from 1985 through 2014. Patients were excluded from the analysis if they had less than 1 year of follow-up, were diagnosed with HGD or EAC within the past year, were missing baseline histologic data, or had no intestinal metaplasia. Seventy percent of the patients were used to derive the model and 30% were used for the validation study. The primary outcome was development of HGD or EAC during the follow-up period (median, 5.9 years). Survival analysis was performed using the Kaplan-Meier method. We assigned a specific number of points to each BE risk factor, and point totals (scores) were used to create categories of low, intermediate, and high risk. We used Cox regression to compute hazard ratios and 95% confidence intervals to determine associations between risk of progression and scores. RESULTS: Of 4584 patients in the database, 2697 were included in our analysis (84.1% men; 87.6% Caucasian; mean age, 55.4 ± 20.1 years; mean body mass index, 27.9 ± 5.5 kg/m2; mean length of BE, 3.7 ± 3.2 cm). During the follow-up period, 154 patients (5.7%) developed HGD or EAC, with an annual rate of progression of 0.95%. Male sex, smoking, length of BE, and baseline-confirmed low-grade dysplasia were significantly associated with progression. Scores assigned identified patients with BE that progressed to HGD or EAC with a c-statistic of 0.76 (95% confidence interval, 0.72-0.80; P < .001). The calibration slope was 0.9966 (P = .99), determined from the validation cohort. CONCLUSIONS: We developed a scoring system (Progression in Barrett's Esophagus score) based on male sex, smoking, length of BE, and baseline low-grade dysplasia that identified patients with BE at low, intermediate, and high risk for HGD or EAC. This scoring system might be used in management of patients.

Lower Annual Rate of Progression of Short-Segment vs Long-Segment Barrett's Esophagus to Esophageal Adenocarcinoma.

BACKGROUND & AIMS: European guidelines recommend different surveillance intervals of non-dysplastic Barrett's esophagus (NDBE) based on segment length, as opposed to guidelines in the United States, which do recommend surveillance intervals based on BE length. We studied rates of progression of NDBE to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) in patients with short-segment BE using the definition of BE in the latest guidelines (length ≥1 cm). METHODS: We collected demographic, clinical, endoscopy, and histopathology data from 1883 patients with endoscopic evidence of NDBE (mean age, 57.3 years; 83.5% male; 88.1% Caucasians) seen at 7 tertiary referral centers. Patients were followed for a median 6.4 years. Cases of dysplasia or EAC detected within 1 year of index endoscopy were considered prevalent and were excluded. Unadjusted rates of progression to HGD or EAC were compared between patients with short (≥1 and <3) and long (≥3) BE lengths using log-rank tests. A subgroup analysis was performed on patients with a documented Prague C&M classification. We used a multivariable proportional hazards model to evaluate the association between BE length and progression. Adjusted hazards ratios were calculated after adjusting for variables associated with progression. RESULTS: We found 822 patients to have a short-segment BE (SSBE) and 1061 to have long segment BE (LSBE). We found patients with SSBE to have a significantly lower annual rate of progression to EAC (0.07%) than of patients with LSBE (0.25%) (P = .001). For the combined endpoint of HGD or EAC, annual progression rates were significantly lower among patients with SSBE (0.29%) compared to compared to LSBE (0.91%) (P < .001). This effect persisted in multivariable analysis (hazard ratio, 0.32; 95% CI, 0.18-0.57; P < .001). CONCLUSION: We analyzed progression of BE (length ≥1 cm) to HGD or EAC in a large cohort of patients seen at multiple centers and followed for a median 6.4 years. We found a lower annual rate of progression of SSBE to EAC (0.07%/year) than of LSBE (0.25%/year). We propose lengthening current surveillance intervals for patients with SSBE.

Increasing prevalence of high-grade dysplasia and adenocarcinoma on index endoscopy in Barrett's esophagus over the past 2 decades: data from a multicenter U.S. consortium.

INTRODUCTION: Data on time trends of dysplasia and esophageal adenocarcinoma (EAC) in Barrett's esophagus (BE) during the index endoscopy (ie, prevalent cases) are limited. Our aim was to determine the prevalence patterns of BE-associated dysplasia on index endoscopy over the past 25 years. METHODS: The Barrett's Esophagus Study is a multicenter outcome project of a large cohort of patients with BE. Proportions of patients with index endoscopy findings of no dysplasia (NDBE), low-grade dysplasia (LGD), high-grade dysplasia (HGD), and EAC were extracted per year of index endoscopy, and 5-yearly patient cohorts were tabulated over years 1990 to 2010+ (2010-current). Prevalent dysplasia and endoscopic findings were trended over the past 25 years using percentage dysplasia (LGD, HGD, EAC, and HGD/EAC) to assess changes in detection of BE-associated dysplasia over the last 25 years. Statistical analysis was done using SAS version 9.4 software (SAS, Cary, NC). RESULTS: A total of 3643 patients were included in the analysis with index endoscopy showing NDBE in 2513 (70.1%), LGD in 412 (11.5%), HGD in 193 (5.4%), and EAC in 181 (5.1%). Over time, there was an increase in the mean age of patients with BE (51.7 ± 29 years vs 62.6 ± 11.3 years) and the proportion of males (84% vs 92.6%) diagnosed with BE but a decrease in the mean BE length (4.4±4.3 cm vs 2.9±3.0 cm) as time progressed (1990-1994 to 2010-2016 time periods). The presence of LGD on index endoscopy remained stable over 1990 to 2016. However, a significant increase (148% in HGD and 112% in EAC) in the diagnosis of HGD, EAC, and HGD/EAC was noted on index endoscopy over the last 25 years (P < .001). There was also a significant increase in the detection of visible lesions on index endoscopy (1990-1994, 5.1%; to 2005-2009, 6.3%; and 2010+, 16.3%) during the same period. CONCLUSION: Our results suggest that the prevalence of HGD and EAC has significantly increased over the past 25 years despite a decrease in BE length during the same period. This increase parallels an increase in the detection of visible lesions, suggesting that a careful examination at the index examination is crucial.

Low Risk of High-Grade Dysplasia or Esophageal Adenocarcinoma Among Patients With Barrett's Esophagus Less Than 1 cm (Irregular Z Line) Within 5 Years of Index Endoscopy.

BACKGROUND & AIMS: Many patients with a < 1 cm segment of columnar metaplasia in the distal esophagus, also called an irregular Z line, are encountered. These patients, often referred to as patients with Barrett's esophagus (BE), are enrolled in surveillance programs. However, little is known about their risk of high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC). We aimed to determine the incidence of HGD and EAC in patients with irregular Z line with intestinal metaplasia. METHODS: We performed a prospective, multicenter cohort study of patients who underwent endoscopic examination for BE at tertiary care referral centers in the United States and Europe. We analyzed data from 1791 patients (mean age, 56 ± 17 years) found to have non-dysplastic BE at the index endoscopy and after 1 year or more of follow-up. Patients were followed for a median of 5.9 years (interquartile range, 3.1-8.3 years). We calculated rates of progression to HGD or EAC between groups of patients with irregular Z line (n = 167) and those with BE of ≥ 1 cm (n = 1624). RESULTS: A higher proportion of patients in the irregular Z-line group were female (26.3%) than in the BE group (14.8% female BE) (P <.001). A lower proportion of patients in the irregular Z-line group were smokers (33.5%) than in the BE group (52.6% smokers). None of the patients with irregular Z line developed HGD or EAC during a median follow-up period of 4.8 years (interquartile range, 3.2-8.3 years). All 71 incident cases of HGD or EAC developed in patients with BE of ≥1 cm in length. On multivariate analysis, patients with irregular Z line and patients with BE of ≥ 1 cm did not differ significantly in age, race, or duration of follow-up. CONCLUSIONS: In a prospective, multicenter cohort study, we found that patients with irregular Z line do not develop HGD or esophageal cancer within 5 years after index endoscopy.

Discordance Among Pathologists in the United States and Europe in Diagnosis of Low-Grade Dysplasia for Patients With Barrett's Esophagus.

BACKGROUND & AIMS: There is suboptimal inter-observer agreement, even among expert gastrointestinal pathologists, in the diagnosis of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE). We analyzed histopathologic criteria required for a diagnosis of LGD using the new subcategories of LGD with inflammatory and dysplastic features. We categorized each diagnosis based on the level of confidence and assessed inter-observer agreement among gastrointestinal pathologists from 5 tertiary centers in the United States and Europe. METHODS: In the first phase of the study, 3 pathologists held a consensus conference at which they discussed the diagnostic criteria for LGD. In the second phase, 79 slides from patients with BE (23 samples of non-dysplastic BE, 22 samples of LGD, and 34 samples of high-grade dysplasia) were identified, randomly assigned to 7 pathologists (4 from the United States and 3 from Europe), and interpreted in a blinded fashion. κ Values were calculated for inter-observer agreement. We performed multinomial logistic regression analysis to assess the weighting of histologic features with the diagnosis. RESULTS: The overall κ value for diagnosis was 0.43 (95% confidence interval [CI], 0.42-0.48). When categorized based on degree of dysplasia, the κ value was 0.22 (95% CI, 0.11-0.29) for non-dysplastic BE, 0.11 (95% CI, 0.004-0.15) for LGD, and 0.43 (95% CI, 0.36-0.46) for high-grade dysplasia. When all pathologists made a diagnosis with high confidence, the inter-observer agreement was substantial among the US pathologists (κ, 0.63; 95% CI, 0.61-0.66) and European pathologists (κ, 0.80; 95% CI, 0.74-0.97). The κ values for all diagnoses made by European pathologists were higher than those made by US pathologists. CONCLUSIONS: In an analysis of criteria used in histopathologic diagnosis of LGD, we did not observe improvement in level of agreement among experienced pathologists, even after accounting for inflammation. The level of inter-observer agreement increased with level of pathologist confidence. There was also a difference in reading of histopathology samples of BE tissues between US and European pathologists.

A Multi-Institutional Prospective Trial Confirms Noninvasive Blood Test Maintains Predictive Value in African American Men.

PURPOSE: The 4Kscore® test accurately detects aggressive prostate cancer and reduces unnecessary biopsies. However, its performance in African American men has been unknown. We assessed test performance in a cohort of men with a large African American representation. MATERIALS AND METHODS: Men referred for prostate biopsy at 8 Veterans Affairs medical centers were prospectively enrolled in the study. All men underwent phlebotomy for 4Kscore test assessment prior to prostate biopsy. The primary outcome was the detection of Grade Group 2 or higher cancer on biopsy. We assessed the discrimination, calibration and clinical usefulness of 4Kscore to predict Grade Group 2 or higher prostate cancer and compared it to a base model consisting of age, digital rectal examination and prostate specific antigen. Additionally, we compared test performance in African American and nonAfrican American men. RESULTS: Of the 366 enrolled men 205 (56%) were African American and 131 (36%) had Grade Group 2 or higher prostate cancer. The 4Kscore test showed better discrimination (AUC 0.81 vs 0.74, p <0.01) and higher clinical usefulness on decision curve analysis than the base model. Test prediction closely approximated the observed risk of Grade Group 2 or higher prostate cancer. There was no difference in test performance in African American and nonAfrican American men (0.80 vs 0.84, p = 0.32), The test outperformed the base model in each group. CONCLUSIONS: The 4Kscore test accurately predicts aggressive prostate cancer for biopsy decision making in African American and nonAfrican American men.

Validation of Probe-based Confocal Laser Endomicroscopy (pCLE) Criteria for Diagnosing Colon Polyp Histology.

BACKGROUND: Validated probe-based confocal endomicroscopy (pCLE) criteria for distinguishing hyperplastic polyps (HPs) and tubular adenomas (TA) have not yet been developed. AIM: To develop pCLE criteria for distinguishing HP from TA and evaluate its performance characteristics among experts. METHODS: pCLE criteria for colon polyp histology were developed and tested in 2 phases prospectively. Phase I: 8 preliminary criteria were developed and tested internally. Criteria achieving an accuracy of >75% (epithelial surface: regular vs. irregular; goblet cells: increased vs. decreased; gland axis: horizontal vs. vertical; gland shape: slit/stellate vs. villiform; image scale: gray vs. dark) were evaluated in Phase II of study wherein external assessors evaluated these criteria in a separate set of pCLE videos. Accuracy and interobserver agreement (95% confidence intervals) were determined for colon histology prediction. RESULTS: Phase I (criteria development/internal testing): 8 criteria were assessed by 4 pCLE experts using 28 videos (14 HP/14 TA). Five of 8 pCLE criteria met selection for phase II (accuracy >75%). Phase II (external validation): 36 pCLE colon polyp videos (HP 16/TA 20) were evaluated by 8 external assessors. Overall accuracy in diagnosis of colon polyp histology was 84.9% (95% confidence interval, 81.7-87.7). Of predictions made with high confidence (75%), histology was predicted with an accuracy of 91%, sensitivity 83%, specificity 100%, negative predictive value 87% and positive predictive value 98%. Interobserver agreement was substantial (κ=0.73). CONCLUSIONS: We demonstrate the development and validation of pCLE criteria for prediction of colon polyp histology. Using these criteria, overall accuracy in differentiating TA from HP was high with substantial interobserver agreement.

In-class didactic versus self-directed teaching of the probe-based confocal laser endomicroscopy (pCLE) criteria for Barrett's esophagus.

BACKGROUND AND AIMS: Optimal teaching methods for disease recognition using probe-based confocal laser endomicroscopy (pCLE) have not been developed. Our aim was to compare in-class didactic teaching vs. self-directed teaching of Barrett's neoplasia diagnosis using pCLE. METHODS: This randomized controlled trial was conducted at a tertiary academic center. Study participants with no prior pCLE experience were randomized to in-class didactic (group 1) or self-directed teaching groups (group 2). For group 1, an expert conducted a classroom teaching session using standardized educational material. Participants in group 2 were provided with the same material on an audio PowerPoint. After initial training, all participants graded an initial set of 20 pCLE videos and reviewed correct responses with the expert (group 1) or on audio PowerPoint (group 2). Finally, all participants completed interpretations of a further 40 videos. RESULTS: Eighteen trainees (8 medical students, 10 gastroenterology trainees) participated in the study. Overall diagnostic accuracy for neoplasia prediction by pCLE was 77 % (95 % confidence interval [CI] 74.0 % - 79.2 %); of predictions made with high confidence (53 %), the accuracy was 85 % (95 %CI 81.8 % - 87.8 %). The overall accuracy and interobserver agreement was significantly higher in group 1 than in group 2 for all predictions (80.4 % vs. 73 %; P = 0.005) and for high confidence predictions (90 % vs. 80 %; P < 0.001). Following feedback (after the initial 20 videos), the overall accuracy improved from 73 % to 79 % (P = 0.04), mainly driven by a significant improvement in group 1 (74 % to 84 %; P < 0.01). Accuracy of prediction significantly improved with time in endoscopy training (72 % students, 77 % FY1, 82 % FY2, and 85 % FY3; P = 0.003). CONCLUSION: For novice trainees, in-class didactic teaching enables significantly better recognition of the pCLE features of Barrett's esophagus than self-directed teaching. The in-class didactic group had a shorter learning curve and were able to achieve 90 % accuracy for their high confidence predictions.

RalA is overactivated in medulloblastoma.

Medulloblastoma (MDB) represents a major form of malignant brain tumors in the pediatric population. A vast spectrum of research on MDB has advanced our understanding of the underlying mechanism, however, a significant need still exists to develop novel therapeutics on the basis of gaining new knowledge about the characteristics of cell signaling networks involved. The Ras signaling pathway, one of the most important proto-oncogenic pathways involved in human cancers, has been shown to be involved in the development of neurological malignancies. We have studied an important effector down-stream of Ras, namely RalA (Ras-Like), for the first time and revealed overactivation of RalA in MDB. Affinity precipitation analysis of active RalA (RalA-GTP) in eight MDB cell lines (DAOY, RES256, RES262, UW228-1, UW426, UW473, D283 and D425) revealed that the majority contained elevated levels of active RalA (RalA-GTP) as compared with fetal cerebellar tissue as a normal control. Additionally, total RalA levels were shown to be elevated in 20 MDB patient samples as compared to normal brain tissue. The overall expression of RalA, however, was comparable in cancerous and normal samples. Other important effectors of RalA pathway including RalA binding protein-1 (RalBP1) and protein phosphatase A (PP2A) down-stream of Ral and Aurora kinase A (AKA) as an upstream RalA activator were also investigated in MDB. Considering the lack of specific inhibitors for RalA, we used gene specific silencing in order to inhibit RalA expression. Using a lentivirus expressing anti-RalA shRNA we successfully inhibited RalA expression in MDB and observed a significant reduction in proliferation and invasiveness. Similar results were observed using inhibitors of AKA and geranyl-geranyl transferase (non-specific inhibitors of RalA signaling) in terms of loss of in vivo tumorigenicity in heterotopic nude mouse model. Finally, once tested in cells expressing CD133 (a marker for MDB cancer stem cells), higher levels of RalA activation was observed. These data not only bring RalA to light as an important contributor to the malignant phenotype of MDB but introduces this pathway as a novel target in the treatment of this malignancy.

Clinical outcomes in patients with a diagnosis of "indefinite for dysplasia" in Barrett's esophagus: a multicenter cohort study.

BACKGROUND AND STUDY AIM: Data are limited on the natural history of patients with Barrett's esophagus with a diagnosis of "indefinite for dysplasia" (IND). The aims of this study were to: (i) determine rates of progression to high grade dysplasia (HGD) or esophageal adenocarcinoma, and compare these with rates for low grade dysplasia (LGD); and (ii) determine the proportion of patients whose histological IND diagnosis changed on follow-up endoscopy. PATIENTS AND METHODS: Demographic, endoscopic, and histologic information of patients with diagnoses of IND and LGD and at least 12 months of follow-up were extracted from the database of a multicenter Barrett's esophagus study. Rates and times for progression to HGD and esophageal adenocarcinoma and regression to nondysplastic epithelium were calculated. Proportions of diagnoses upgraded to HGD/esophageal adenocarcinoma or downgraded to nondysplastic epithelium at first follow-up endoscopy were evaluated. RESULTS: Amongst 2264 patients, 83 with a diagnosis of IND (mean age 60 years, 95 % men, 95 % white; mean follow-up 5.6 years) and 79 with diagnosis of LGD were identified. In the IND group, annual incidences of esophageal adenocarcinoma and HGD were 0.21 % and 0.64 %, respectively, representing a combined incidence of 0.8 %. Mean time to progression was 4.72 years. Within the IND group 55 % patients showed regression to nondysplastic epithelium at first follow-up endoscopy and the overall regression rate was 80 %. Corresponding rates in LGD patients were similar. CONCLUSIONS: Lesions diagnosed as IND and LGD show similar biological behavior and can be treated as a single category with respect to surveillance and follow-up.

Persistence of nondysplastic Barrett's esophagus identifies patients at lower risk for esophageal adenocarcinoma: results from a large multicenter cohort.

BACKGROUND & AIMS: Recent population-based studies have shown a low risk of esophageal adenocarcinoma (EAC) in patients with nondysplastic Barrett's esophagus (NDBE). We evaluated whether persistence of NDBE over multiple consecutive surveillance endoscopic examinations could be used in risk stratification of patients with Barrett's esophagus (BE). METHODS: We performed a multicenter outcomes study of a large cohort of patients with BE. Based on the number of consecutive surveillance endoscopies showing NDBE, we identified 5 groups of patients. Patients in group 1 were found to have NDBE at their first esophagogastroduodenoscopy (EGD). Patients in group 2 were found to have NDBE on their first 2 consecutive EGDs. Similarly, patients in groups 3, 4, and 5 were found to have NDBE on 3, 4, and 5 consecutive surveillance EGDs. A logistic regression model was built to determine whether persistence of NDBE independently protected against development of cancer. RESULTS: Of a total of 3515 patients with BE, 1401 patients met the inclusion criteria (93.3% white; 87.5% men; median age, 60 ±17 years). The median follow-up period was 5 ± 3.9 years (7846 patient-years). The annual risk of EAC in groups 1 to 5 was 0.32%, 0.27%, 0.16%, 0.2%, and 0.11%, respectively (P for trend = .03). After adjusting for age, sex, and length of BE, persistence of NDBE, based on multiple surveillance endoscopies, was associated with a gradually lower likelihood of progression to EAC. CONCLUSIONS: Persistence of NDBE over several endoscopic examinations identifies patients who are at low risk for development of EAC. These findings support lengthening surveillance intervals or discontinuing surveillance of patients with persistent NDBE.

Standard endoscopy with random biopsies versus narrow band imaging targeted biopsies in Barrett's oesophagus: a prospective, international, randomised controlled trial.

BACKGROUND: White light endoscopy with random biopsies is the standard for detection of intestinal metaplasia (IM) and neoplasia in patients with Barrett's oesophagus (BO). Narrow band imaging (NBI) highlights surface patterns that correlate with IM and neoplasia in BO. OBJECTIVE: To compare high-definition white light (HD-WLE) and NBI for detection of IM and neoplasia in BO. DESIGN: International, randomised, crossover trial comparing HD-WLE and NBI. Patients referred for BO screening/surveillance at three tertiary referral centres were prospectively enrolled and randomised to HD-WLE or NBI followed by other procedures in 3-8 weeks. During HD-WLE, four quadrant biopsies every 2 cm, together with targeted biopsies of visible lesions (Seattle protocol), were obtained. During NBI examination, mucosal and vascular patterns were noted and targeted biopsies were obtained. All biopsies were read by a single expert gastrointestinal pathologist in a blinded fashion. RESULTS: 123 patients with BO (mean age 61; 93% male; 97% Caucasian) with mean circumferential and maximal extents of 1.8 and 3.6 cm, respectively, were enrolled. Both HD-WLE and NBI detected 104/113 (92%) patients with IM, but NBI required fewer biopsies per patient (3.6 vs 7.6, p<0.0001). NBI detected a higher proportion of areas with dysplasia (30% vs 21%, p=0.01). During examination with NBI, all areas of high-grade dysplasia and cancer had an irregular mucosal or vascular pattern. CONCLUSIONS: NBI targeted biopsies can have the same IM detection rate as an HD-WLE examination with the Seattle protocol while requiring fewer biopsies. In addition, NBI targeted biopsies can detect more areas with dysplasia. Regular appearing NBI surface patterns did not harbour high-grade dysplasia/cancer, suggesting that biopsies could be avoided in these areas.

Clinical utility and interobserver agreement of autofluorescence imaging and magnification narrow-band imaging for the evaluation of Barrett's esophagus: a prospective tandem study.

BACKGROUND: New endoscopic imaging techniques, such as autofluorescence imaging (AFI) and narrow-band imaging (NBI), have been developed to improve the detection of neoplastic lesions in Barrett's esophagus (BE). OBJECTIVE: To evaluate the clinical utility of AFI and magnification NBI to detect high-grade dysplasia (HGD) and early esophageal adenocarcinoma (EAC) and the interobserver agreement. DESIGN: Prospective tandem study of eligible patients. SETTING: Single, academic tertiary care center. PATIENTS: Forty-two patients with a history of confirmed BE were prospectively enrolled. INTERVENTIONS: The BE segment was examined under high-definition white-light endoscopy, and the presence of visible lesions was recorded. Subsequently, AFI and magnification NBI were performed in tandem on areas of the BE segment away from visible lesions; images obtained by these 2 systems were graded according to the color of reflected light and surface patterns, respectively. Biopsy specimens were obtained at the end of the procedure. MAIN OUTCOME MEASUREMENTS: The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of the AFI and NBI patterns for the detection of HGD/EAC and interobserver agreement. RESULTS: Of the 42 patients enrolled, 14 (33%) had HGD/EAC. On patient-based analysis, AFI alone had a sensitivity, specificity, and NPV of 50%, 61%, and 71%, respectively, and the overall accuracy for the detection of HGD/EAC patients was 57%. By using magnification NBI in tandem fashion, the sensitivity and NPV improved to 71% and 76%, respectively, with a decrease in specificity to 46% and in overall accuracy to 55%. The 2 techniques had moderate interobserver agreement for both the patterns and prediction of histology. LIMITATIONS: Uncontrolled study performed at an academic center by expert endoscopists in a high-risk population. CONCLUSIONS: By using a multimodality endoscope, both AFI and magnification NBI had limited clinical accuracy and moderate overall interobserver agreement. AFI does not appear to be useful as a broad-based technique for the detection of neoplasia in patients with BE.

Risk factors for progression of low-grade dysplasia in patients with Barrett's esophagus.

BACKGROUND & AIMS: Data vary on the progression of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE); in patients with LGD, we investigated the incidence of high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) and compared progression in patients with different forms of LGD (prevalent vs incident and multifocal vs unifocal). We assessed the effects of consensus diagnosis of LGD on progression rates to HGD and EAC among expert pathologists. METHODS: In a multicenter outcomes project, 210 patients with BE and LGD (classified as incident, prevalent, or persistent) were included. Patients were followed up for an average of 6.2 years (959.6 patient-years). Persistent LGD was defined as detection of LGD on ≥2 consecutive occasions during the follow-up period and extent as either unifocal (LGD at one level of BE segment) or multifocal (>1 level). Histology specimens were reviewed by 2 blinded pathologists. RESULTS: Six patients developed EAC (incidence of 0.44%/year), and 21 developed HGD (incidence of 1.6%/year). The incidence of the combination of HGD and EAC was 1.83%/year. There were no associations between presence of prevalent, incident, or persistent LGD and the extent of LGD with progression rates. Based on consensus diagnosis of 88 reviewed specimens, there was no difference in the progression of LGD to either EAC (the incidence based on analyses by the local pathologist was 0.18%/year, the incidence when there was agreement between the local and one central pathologist was 0.21%/year, and the incidence when all 3 pathologists were in agreement was 0.39%/year) or combined HGD and EAC (0.94%/year, 0.87%/year, and 0.84%/year, respectively). CONCLUSIONS: Overall, patients with BE and LGD have a low annual incidence of EAC, similar to nondysplastic BE. There are no risk factors for progression and there is significant interobserver variation in diagnosis, even among expert pathologists.