Staging of T1 esophageal adenocarcinoma with volumetric laser endomicroscopy: a feasibility study

Background and study aims  Precise staging in T1 esophageal adenocarcinoma (EAC) is critical in determining candidacy for curative endoscopic resection. High-frequency endoscopic ultrasound (EUS) has demonstrated suboptimal accuracy in T1 EAC staging due to insufficient spatial resolution. Volumetric laser endomicroscopy (VLE) allows for high-resolution wide-field visualization of the esophageal microstructure. We aimed to investigate the role of VLE in staging T1 EAC. Patients and methods  Patients undergoing endoscopic mucosal resection (EMR) were prospectively enrolled and only T1 EAC cases were included. EMR specimens were imaged using second-generation VLE immediately after resection. VLE images were analyzed for signal intensity by depth and signal attenuation (dB/mm) in both cross-sectional and en-face orientation. A decision tree model was constructed to combine measured VLE parameters and delineate diagnostic thresholds. Results  Thirty EMR scans were obtained - 15 T1a specimens from 9 patients and 15 T1b specimens from 11 patients. T1b specimen VLE scans exhibited higher signal intensity ( P  < 0.0001) and higher signal attenuation compared to T1a specimens ( P  = 0.03). A combination of signal attenuation and signal intensity at 150 µm depth yielded optimal diagnostic thresholds and an area under the curve (AUC) of 0.77. VLE signal attenuation was significantly associated with grade of differentiation, irrespective of EAC stage. Conclusions  VLE signal intensity and signal attenuation are quantitatively distinct in T1a and T1b EAC and associated with grade of differentiation. This is the first study examining the role of VLE for staging of T1 EAC and demonstrates promising diagnostic performance. With further in vivo validation, VLE may serve a role in staging superficial EAC.

Combined Celiac Ganglia and Plexus Neurolysis Shortens Survival, Without Benefit, vs Plexus Neurolysis Alone

BACKGROUND & AIMS

Pancreatic cancer produces debilitating pain that opioids often ineffectively manage. The suboptimal efficacy of celiac plexus neurolysis (CPN) might result from brief contact of the injectate with celiac ganglia. We compared the effects of endoscopic ultrasound-guided celiac ganglia neurolysis (CGN) vs the effects of CPN on pain, quality of life (QOL), and survival.

METHODS

We performed a randomized, double-blind trial of patients with unresectable pancreatic ductal adenocarcinoma and abdominal pain; 60 patients (age 66.4±11.6 years; male 66%) received CPN and 50 patients (age 66.8±10.0 years; male 56%) received CGN. Primary outcomes included pain control and QOL at week 12 and survival (overall median and 12 months). Secondary outcomes included morphine response, performance status, secondary neurolytic effects, and adverse events.

RESULTS

Rates of pain response at 12 weeks were 46.2% for CGN and 40.4% for CPN (P = .84). There was no significant difference in improvement of QOL between the techniques. The median survival time was significantly shorter for patients receiving CGN (5.59 months) compared to (10.46 months) (hazard ratio for CGN, 1.49; 95% CI, 1.02-2.19; P = .042), particularly for patients with non-metastatic disease (hazard ratio for CGN, 2.95; 95% CI, 1.61-5.45; P < .001). Rates of survival at 12 months were 42% for patients who underwent CPN vs 26% for patients who underwent CGN. The number of adverse events did not differ between techniques.

CONCLUSION

In a prospective study of patients with unresectable pancreatic ductal adenocarcinoma and abdominal pain, we found CGN to reduce median survival time without improving pain, QOL, or adverse events, compared to CPN. The role of CGN must be therefore be reassessed. Clinicaltrials.gov no: NCT01615653.

Accuracy of Endoscopic Ultrasound Imaging in Distinguishing Celiac Ganglia From Celiac Lymph Nodes

BACKGROUND & AIMS

Endoscopic ultrasound (EUS) allows visualization of celiac lymph nodes (CLNs) and celiac ganglia (CG). Reliably distinguishing these structures is important for tumor staging and CG ablative therapies. We aimed to evaluate the accuracy of EUS in distinguishing CLNs from CG using a strict cytopathology reference standard. We also determined the rate of detection of CLN and CG by conventional cross-sectional imaging.

METHODS

From EUS and cytopathology databases, we identified all patients who underwent EUS-FNA of a presumed CLN or CG from October 1, 2004, through March 1, 2017, and compared the findings with those from cytology (reference standard). Indeterminate cytology results were re-reviewed. EUS imaging (ie, index test) results were compared with those from the reference standard. An expert radiologist re-reviewed computed tomography and magnetic resonance images from 100 lesions, from 94 randomly selected patients with a reference standard, to determine the rates of CLN and CG detection.

RESULTS

A total of 504 patients (mean age, 63.4 ± 13.2 years; 292 men) underwent a median of 7 EUS-FNA passes (range, 1-13) for a total of 566 lesions perceived to be either a CLN or CG; the cytology reference standard was available for 521 lesions (92.1%). When we excluded indeterminate cytology results, the EUS accurately identified 281/286 CLNs (98.3%) and 166/186 CGs (89.2%), for an overall accuracy of 447/472 (94.7%). EUS-FNA distinguished CG from CLNs with a 93.3% sensitivity, 93.7% specificity, a positive predictive value of 96.2%, and a negative predictive value of 89.2%. Of 100 lesions in 94 patients randomly selected for a second expert radiology review, computed tomography and magnetic resonance imaging detected 59/67 CLNs (88.1%) and 13/33 CG (39.4%).

CONCLUSION

EUS accurately distinguishes CLNs from CG. EUS might therefore be used to increase the accuracy of tumor staging, to select tumor stage-appropriate therapy, and to guide CG-ablative therapies.

Identification of Prognostic Phenotypes of Esophageal Adenocarcinoma in 2 Independent Cohorts

BACKGROUND & AIMS

Most patients with esophageal adenocarcinoma (EAC) present with de novo tumors. Although this could be due to inadequate screening strategies, the precise reason for this observation is not clear. We compared survival of patients with prevalent EAC with and without synchronous Barrett esophagus (BE) with intestinal metaplasia (IM) at the time of EAC diagnosis.

METHODS

Clinical data were studied using Cox proportional hazards regression to evaluate the effect of synchronous BE-IM on EAC survival independent of age, sex, TNM stage, and tumor location. We analyzed data from a cohort of patients with EAC from the Mayo Clinic (n=411; 203 with BE and IM) and a multicenter cohort from the United Kingdom (n=1417; 638 with BE and IM).

RESULTS

In the Mayo cohort, BE with IM had a reduced risk of death compared to patients without BE and IM (hazard ratio [HR] 0.44; 95% CI, 0.34-0.57; P<.001). In a multivariable analysis, BE with IM was associated with longer survival independent of patient age or sex, tumor stage or location, and BE length (adjusted HR, 0.66; 95% CI, 0.5-0.88; P=.005). In the United Kingdom cohort, patients BE and IM had a reduced risk of death compared with those without (HR, 0.59; 95% CI, 0.5-0.69; P<.001), with continued significance in multivariable analysis that included patient age and sex and tumor stage and tumor location (adjusted HR, 0.77; 95% CI, 0.64-0.93; P=.006).

CONCLUSION

Two types of EAC can be characterized based on the presence or absence of BE. These findings could increase our understanding the etiology of EAC, and be used in management and prognosis of patients.

Clutch cutter is a safe device for performing endoscopic submucosal dissection of superficial esophageal neoplasms: a western experience

Although the endoscopic submucosal dissection (ESD) has been established to be more efficacious in the treatment of superficial gastrointestinal neoplasia than the piecemeal resection, its use is still limited due to the concern about serious adverse events particularly in the west. Newer ESD knives have been developed that have been said to be safer than the first-generation devices. We aimed to report a Western single center experience regarding the initial safety and performance of ESD for superficial esophageal neoplasia treated with the Clutch Cutter (DP2618DT; Fujifilm Corporation, Tokyo, Japan). Our main outcome was safety in terms of bleeding or perforation. Secondary outcomes included en bloc resection and the R0 resection. Fourteen patients with superficial esophageal neoplasia underwent 15 ESDs using the Clutch Cutter. The mean age was 65 ± 16.7 years and 10 (71.4%) males. Eight (57%) patients had esophageal adenocarcinoma, 3 (21.4%) had high-grade dysplasia, 1 (7%) had nodular low-grade dysplasia, and 2 (14.3%) had squamous cell carcinoma. Mild anticipated intraprocedural bleeding was present with most procedures. However, no significant postoperative bleeding or perforation was encountered. One patient had mild chest pain postprocedure. En bloc resection was achieved in all lesions 100%. Histological R0 was achieved in 5/12 lesions (41.6%). The mean length of the resected area was 24.8 ± 13 mm (IQR: 17-30 mm). All patients were safely discharged home after overnight observation. In conclusion, this is the largest series of esophageal ESD using the multimodal Clutch Cutter in the United States; we found that the device effectively achieved en bloc resection of superficial esophageal neoplasia without significant adverse events. The use of the Clutch Cutter should be considered as one option to minimize adverse events during ESD in the Western population.

Comparative assessment of atherosclerosis of rabbit femoral artery by Duplex Ultrasound Scanning, Optical Coherence Tomography and Fractional Flow Reserve

Duplex Ultrasound Scanning (DUS), Frequency-domain optical coherence tomography (FD-OCT) and fractional flow reserve (FFR) remarkably shape our understanding of the significance of coronary stenosis. The present study aimed to compare the assessment results of the atherosclerotic lesions in rabbit superficial femoral artery by DUS with that of FD-OCT and FFR. A total of 20 atherosclerotic lesions were analyzed. Morphological assessments were prospectively compared through DUS, FD-OCT and quantitative superficial femoral angiography (QFA). In addition, the correlation between DUS derived lesion parameters and FFR was determined. The results show that, compared with FD-OCT and QFA, DUS detected larger reference diameter and higher percent stenosis. However, the minimal lumen diameter (MLD) and distance from profunda femoris to MLD were equivalent measured by the three imaging modalities. There was a poor correlation between FFR and DUS-derived percent diameter stenosis (R2=0.198, P=0.049). In conclusion, hemodynamic significance of lesions assessed by FFR was only related with percent diameter stenosis measured by DUS.

A prospective multicenter study using a new multiband mucosectomy device for endoscopic resection of early neoplasia in Barrett's esophagus

BACKGROUND AND AIMS

Early neoplasia in Barrett's esophagus (BE) can be effectively and safely removed by endoscopic resection (ER) using multiband mucosectomy (MBM). This study aimed to document performance of a novel MBM device designed for improved visualization, easier passage of accessories, and better suction power compared with other marketed MBM devices.

METHODS

This international, single-arm, prospective registry in 14 referral centers (Europe, 10; United States, 3; Canada, 1) included patients with early BE neoplasia scheduled for ER. The primary endpoint was successful ER defined as complete resection of the delineated area in 1 procedure. Secondary outcomes were adverse events and procedure time.

RESULTS

A total of 332 lesions was included in 291 patients (248 men; mean age, 67 years [standard deviation, 9.6]). ER indication was high-grade dysplasia in 64%, early adenocarcinoma in 19%, lesion with low-grade dysplasia in 11%, and a lesion without definite histology in 6%. Successful ER was reached in 322 of 332 lesions (97%; 95% confidence interval [CI], 94.6%-98.4%). A perforation occurred in 3 of 332 procedures (.9%; 95% CI, .31%-2.62%), all were managed endoscopically, and patients were admitted with intravenous antibiotics during days 2, 3, and 9. Postprocedural bleeding requiring an intervention occurred in 5 of 332 resections (1.5%; 95% CI, .65%-3.48%). Dysphagia requiring dilatation occurred in 11 patients (3.8%; 95% CI, 2.1%-6.6%). Median procedure time was 16 minutes (interquartile range, 12.0-26.0).

CONCLUSIONS

In expert hands, the novel MBM device proved to be effective for resection of early neoplastic lesions in BE, with successful ER in 97% of procedures. Severe adverse events were rare and were effectively managed endoscopically or conservatively. (Clinical trial registration number: NCT02482701.).

Volumetric laser endomicroscopy interpretation and feature analysis in dysplastic Barrett's esophagus

BACKGROUND AND AIM

Volumetric laser endomicroscopy (VLE) is used to identify Barrett's esophagus (BE) dysplasia. Selection of a dysplastic region of interest (ROI) can be challenging due to feature variability across a large amount of data. The degree of agreement among VLE users in selecting a ROI has not been studied.

METHODS

High-definition videos that divided a VLE scan from 18 patients with biopsy-proven BE dysplasia into 1-cm segments were reviewed using a four-quadrant grid superimposed for systematic interpretation. VLE scans were selected based on image quality and appropriate visualization of BE epithelium. Four experienced VLE users rated each quadrant as dysplastic or non-dysplastic. For quadrants rated as dysplastic, reviewers selected a single timeframe with representative features. A high-degree of agreement among reviewers was defined as ≥75% agreement on the quadrant diagnosis and ≥50% agreement on selected timeframe (±2 s).

RESULTS

Thirty-one videos, each 32 s in length, comprising 124 quadrants were reviewed. There was high-agreement among reviewers in 99 (80%) quadrants, of which 68 (69%) were rated as dysplastic. Compared with quadrants rated as non-dysplastic, ROIs of quadrants rated as dysplastic contained a higher number of epithelial glands (12.7 vs 1.2, P < 0.001) with atypical architecture (54 vs 1, P < 0.001). A statistically significant difference was observed between the signal intensity profiles of quadrants rated as dysplastic and quadrants rated as non-dysplastic (P = 0.004).

CONCLUSION

This study highlights that experienced VLE users can identify ROIs with high-degree of agreement. Selected ROIs contained VLE features associated with BE dysplasia.

USP7 Cooperates with NOTCH1 to Drive the Oncogenic Transcriptional Program in T-Cell Leukemia

PURPOSE

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease, affecting children and adults. Chemotherapy treatments show high response rates but have debilitating effects and carry risk of relapse. Previous work implicated NOTCH1 and other oncogenes. However, direct inhibition of these pathways affects healthy tissues and cancer alike. Our goal in this work has been to identify enzymes active in T-ALL whose activity could be targeted for therapeutic purposes.

EXPERIMENTAL DESIGN

To identify and characterize new NOTCH1 druggable partners in T-ALL, we coupled studies of the NOTCH1 interactome to expression analysis and a series of functional analyses in cell lines, patient samples, and xenograft models.

RESULTS

We demonstrate that ubiquitin-specific protease 7 (USP7) interacts with NOTCH1 and controls leukemia growth by stabilizing the levels of NOTCH1 and JMJD3 histone demethylase. USP7 is highly expressed in T-ALL and is transcriptionally regulated by NOTCH1. In turn, USP7 controls NOTCH1 levels through deubiquitination. USP7 binds oncogenic targets and controls gene expression through stabilization of NOTCH1 and JMJD3 and ultimately H3K27me3 changes. We also show that USP7 and NOTCH1 bind T-ALL superenhancers, and inhibition of USP7 leads to a decrease of the transcriptional levels of NOTCH1 targets and significantly blocks T-ALL cell growth in vitro and in vivo.

CONCLUSIONS

These results provide a new model for USP7 deubiquitinase activity through recruitment to oncogenic chromatin loci and regulation of both oncogenic transcription factors and chromatin marks to promote leukemia. Our studies also show that targeting USP7 inhibition could be a therapeutic strategy in aggressive leukemia.

Smokeless Tobacco and Cigar and/or Pipe Are Risk Factors for Barrett Esophagus in Male Patients With Gastroesophageal Reflux Disease

OBJECTIVE

To investigate the effect of smokeless tobacco (ST), cigar and/or pipe smoking (CP) on the development of Barrett esophagus (BE) in white male patients with gastroesophageal reflux disease (GERD).

PATIENTS AND METHODS

A total of 1015 records of white male adults with BE (cases; n=508) or GERD (controls, n=507) were reviewed for lifestyle factors. Logistic regression analyses were performed after adjusting for lifestyle factors to assess the effects of ST and CP on the risk of developing BE. Differences between patients with BE and those with GERD were compared using chi-square and t tests.

RESULTS

Patients with BE were significantly older than patients with GERD (mean age, 66±12 years for patients with BE and 55±15 years for patients with GERD; P<.001). The odds of developing BE in patients who used CS were 1.7 times higher than that in patients who never smoked cigarettes (odds ratio [OR], 1.7; 95% CI, 1.3-2.2). It was observed that when CS use was combined with either ST or CP use, the odds of having BE significantly increased (OR, 2.5; 95% CI, 1.2-5.2; P=.01 and OR, 1.9; 95% CI, 1.03-3.58; P=.04) in comparison to CS alone. There were no significant differences in body mass index and alcohol consumption between BE and GERD groups.

CONCLUSION

This study suggests that there is indeed an association between CS and BE. We believe that this is the first time that ST and CP were associated with an even higher odds of developing BE. Further studies are needed to investigate whether the use of ST and CP is also associated with an increased risk of developing BE-associated adenocarcinoma.

Highly Discriminant Methylated DNA Markers for the Non-endoscopic Detection of Barrett's Esophagus

BACKGROUND

Minimally invasive methods have been described to detect Barrett's esophagus (BE), but are limited by subjectivity and suboptimal accuracy. We identified methylated DNA markers (MDMs) for BE in tissue and assessed their accuracy on whole esophagus brushings and capsule sponge samples.

METHODS

Step 1: Unbiased whole methylome sequencing was performed on DNA from BE and normal squamous esophagus (SE) tissue. Discriminant MDM candidates were validated on an independent patient cohort (62 BE cases, 30 controls) by quantitative methylation specific PCR (qMSP). Step 2: Selected MDMs were further evaluated on whole esophageal brushings (49 BE cases, 36 controls). 35 previously sequenced esophageal adenocarcinoma (EAC) MDMs were also evaluated. Step 3: 20 BE cases and 20 controls were randomized to swallow capsules sponges (25 mm, 10 pores or 20 pores per inch (ppi)) followed endoscopy. DNA yield, tolerability, and mucosal injury were compared. Best MDM assays were performed on this cohort.

RESULTS

Step 1: 19 MDMs with areas under the ROC curve (AUCs) >0.85 were carried forward. Step 2: On whole esophageal brushings, 80% of individual MDM candidates showed high accuracy for BE (AUCs 0.84-0.94). Step 3: The capsule sponge was swallowed and withdrawn in 98% of subjects. Tolerability was superior with the 10 ppi sponge with minimal mucosal injury and abundant DNA yield. A 2-marker panel (VAV3 + ZNF682) yielded excellent BE discrimination (AUC = 1).

CONCLUSIONS

Identified MDMs discriminate BE with high accuracy. BE detection appears safe and feasible with a capsule sponge. Corroboration in larger studies is warranted. ClinicalTrials.gov number NCT02560623.

Factors Associated With Progression of Barrett's Esophagus: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Endoscopic surveillance of patients with Barrett's esophagus (BE) is inefficient. Risk stratification of patients might improve the effectiveness of surveillance. We performed a systematic review and meta-analysis to identify factors associated with progression of BE without dysplasia or BE with low-grade dysplasia (LGD) to high-grade dysplasia or esophageal adenocarcinoma.

METHODS

We performed a systematic search of databases through May 2016 to identify cohort studies of patients with baseline BE without dysplasia or BE with LGD that reported predictors of progression. Pooled estimates (odds ratios) of associations of age, sex, smoking, alcohol use, obesity, baseline LGD, segment length, and medication use with progression were calculated.

RESULTS

We identified 20 studies, reporting 1231 events in 74943 patients. The studies associated BE progression with increasing age (12 studies; odds ratio [OR], 1.03; 95% CI, 1.01-1.05), male sex (11 studies; OR, 2.16; 95% CI, 1.84-2.53), ever smoking (current or past, 8 studies; OR, 1.47; 95% CI, 1.09-1.98), and increasing BE segment length (10 studies; OR, 1.25; 95% CI, 1.16-1.36), with a low degree of heterogeneity. LGD was associated with a 4-fold increase in risk of BE progression (11 studies; OR, 4.25; 95% CI, 2.58-7.0). Use of proton pump inhibitors (4 studies; OR, 0.55; 95% CI, 0.32-0.96) or statins (3 studies; OR, 0.48; 95% CI, 0.31-0.73) were associated with lower risk of BE progression. Alcohol use and obesity did not associate with risk of progression.

CONCLUSIONS

In a systematic review and meta-analysis, we associated older age, male sex, smoking, longer BE segment, and LGD with risk of progression of BE. Individuals with these features should undergo more intensive surveillance or endoscopic therapy. Smoking is a modifiable risk factor for cancer prevention in patients with BE.

Cryotherapy for persistent Barrett's esophagus after radiofrequency ablation: a systematic review and meta-analysis

BACKGROUND AND AIMS

A small but significant proportion of patients with Barrett's esophagus (BE) have persistent dysplasia or intestinal metaplasia (IM) after treatment with radiofrequency ablation (RFA). Cryotherapy is a cold-based ablative modality that is increasingly being used in this setting. We aimed to better understand the efficacy of second-line cryotherapy in patients with BE who have persistent dysplasia or IM after RFA by conducting a systematic review and meta-analysis.

METHODS

We performed a systematic literature search of Pubmed, EMBASE, and Web of Science through September 1, 2017. Articles were included for meta-analysis based on the following inclusion criteria: ≥5 patients with BE treated with RFA had persistent dysplasia or IM; they subsequently underwent ≥1 session of cryotherapy with follow-up endoscopy; the proportions of patients achieving complete eradication of dysplasia (CE-D) and/or IM (CE-IM) were reported. The main outcomes were pooled proportions of CE-D and CE-IM by using a random effects model.

RESULTS

Eleven studies making up 148 patients with BE treated with cryotherapy for persistent dysplasia or IM after RFA were included. The pooled proportion of CE-D was 76.0% (95% confidence interval [CI] 57.7-88.0), with substantial heterogeneity (I2 = 62%). The pooled proportion of CE-IM was 45.9% (95% CI, 32.0-60.5) with moderate heterogeneity (I2 = 57%). Multiple preplanned subgroup analyses did not sufficiently explain the heterogeneity. Adverse effects were reported in 6.7% of patients.

CONCLUSION

Cryotherapy successfully achieved CE-D in three fourths and CE-IM in half of patients with BE who did not respond to initial RFA. Considering its favorable safety profile, cryotherapy may be a viable second-line option for this therapeutically challenging cohort of patients with BE, but higher-quality studies validating this remain warranted.

Comparative Molecular Analysis of Gastrointestinal Adenocarcinomas

We analyzed 921 adenocarcinomas of the esophagus, stomach, colon, and rectum to examine shared and distinguishing molecular characteristics of gastrointestinal tract adenocarcinomas (GIACs). Hypermutated tumors were distinct regardless of cancer type and comprised those enriched for insertions/deletions, representing microsatellite instability cases with epigenetic silencing of MLH1 in the context of CpG island methylator phenotype, plus tumors with elevated single-nucleotide variants associated with mutations in POLE. Tumors with chromosomal instability were diverse, with gastroesophageal adenocarcinomas harboring fragmented genomes associated with genomic doubling and distinct mutational signatures. We identified a group of tumors in the colon and rectum lacking hypermutation and aneuploidy termed genome stable and enriched in DNA hypermethylation and mutations in KRAS, SOX9, and PCBP1.

Costs associated with Barrett's esophagus screening in the community: an economic analysis of a prospective randomized controlled trial of sedated versus hospital unsedated versus mobile community unsedated endoscopy

BACKGROUND AND AIMS

Data on the economic impact associated with screening for Barrett's esophagus (BE) are limited. As part of a comparative effectiveness randomized trial of unsedated transnasal endoscopy (uTNE) and sedated EGD (sEGD), we assessed costs associated with BE screening.

METHODS

Patients were randomly allocated to 3 techniques: sEGD or uTNE in a hospital setting (huTNE) versus uTNE in a mobile research van (muTNE). Patients were called 1 and 30 days after screening to assess loss of work (because of the screening procedure) and medical care sought after procedure. Direct medical costs were extracted from billing claims databases. Indirect costs (loss of work for subject and caregiver) were estimated using patient reported data. Statistical analyses including multivariable analysis accounting for comorbidities were conducted to compare costs.

RESULTS

Two hundred nine patients were screened (61 sEGD, 72 huTNE, and 76 muTNE). Thirty-day direct medical costs and indirect costs were significantly higher in the sEGD than the huTNE and muTNE groups. Total costs (direct medical + indirect costs) were also significantly higher in the sEGD than in the uTNE group. The muTNE group had significantly lower costs than the huTNE group. Adjustment for age, sex, and comorbidities on multivariable analysis did not change this conclusion.

CONCLUSIONS

Short-term direct, indirect, and total costs of screening are significantly lower with uTNE compared with sEGD. Mobile uTNE costs were lower than huTNE costs, raising the possibility of mobile screening as a novel method of screening for BE and esophageal adenocarcinoma.

[Spatial and temporal characteristics of HIV/AIDS in Hubei province, 2010-2013]

Objective: To understand the spatial and temporal distribution of HIV/AIDS in Hubei province, and provide scientific evidence for the prevention and control of AIDS. Methods: GeoDa software was used for autocorrelation analysis, SatScan 9.2 software was used for statistical analysis of spatial scanning, and finally geographic information system was used for visualization. Results: A total of 6 952 HIV/AIDS cases were reported during 2010-2013 in Hubei, and the spatial autocorrelation analysis showed that Global Moran's I index was 0.266 (P<0.05), indicating that there was a positive spatial autocorrelation of HIV/AIDS. Global Moran's I index increased year by year (P<0.05), indicating that the increased spatial aggregation of HIV/AIDS during 2010-2013. The local Moran's I index showed that " high-high" clustering areas were in Wuhan, and the number of " high-high" clustering areas increased during 2010-2013. Moreover, the " high-high" clustering areas expanded from Wuhan to surrounding areas. Spatial and temporal scan analysis revealed that 19 counties in Wuhan, Huangshi, Ezhou, Xianning with a radius of 60.01 km (LLR=625.14, RR=3.23) were the main spatial and temporal clustering area during 2012-2013. Conclusion: The spatial changes of HIV/AIDS seemed to be regular from 2010 to 2013 in Wuhan, spatial correlation at provincial level decreased and the " high-high" clustering areas gradually expanded from Wuhan to surrounding areas, indicating that it is necessary to strengthen the AIDS prevention and control in these areas in Hubei.

Late Recurrence of Barrett's Esophagus After Complete Eradication of Intestinal Metaplasia is Rare: Final Report From Ablation in Intestinal Metaplasia Containing Dysplasia Trial

BACKGROUND & AIMS

The goal of treatment for Barrett's esophagus (BE) with dysplasia is complete eradication of intestinal metaplasia (CEIM). The long-term durability of CEIM has not been well characterized, so the frequency and duration of surveillance are unclear. We report results from a 5-year follow-up analysis of patients with BE and dysplasia treated by radiofrequency ablation (RFA) in the randomized controlled Ablation of Intestinal Metaplasia Containing Dysplasia (AIM) trial.

METHODS

Participants for the AIM Dysplasia trial (18-80 years old) were recruited from 19 sites in the United States and had endoscopic evidence of non-nodular dysplastic BE ≤8 cm in length. Subjects (n = 127) were randomly assigned (2:1 ratio) to receive either RFA (entire BE segment ablated circumferentially) or a sham endoscopic procedure; patients in the sham group were offered RFA treatment 1 year later, and all patients were followed for 5 years. We collected data on BE recurrence (defined as intestinal metaplasia in the tubular esophagus) and dysplastic BE recurrence among patients who achieved CEIM. We constructed Kaplan-Meier estimates and applied parametric survival analysis to examine proportions of patients without any recurrence and without dysplastic recurrence.

RESULTS

Of 127 patients in the AIM Dysplasia trial, 119 received RFA and met inclusion criteria. Of those 119, 110 (92%) achieved CEIM. Over 401 person-years of follow-up (mean, 3.6 years per patient; range, 0.2-5.8 years), 35 of 110 (32%) patients had recurrence of BE or dysplasia, and 19 (17%) had dysplasia recurrence. The incidence rate of BE recurrence was 10.8 per 100 person-years overall (95% CI, 7.8-15.0); 8.3 per 100 person-years among patients with baseline low-grade dysplasia (95% CI, 4.9-14.0), and 13.5 per 100 person-years among patients with baseline high-grade dysplasia (95% CI 8.8-20.7). The incidence rate of dysplasia recurrence was 5.2 per 100 person-years overall (95% CI 3.3-8.2); 3.3 per 100 person-years among patients with baseline low-grade dysplasia (95% CI 1.5-7.2), and 7.3 per 100 person-years among patients with baseline high-grade dysplasia (95% CI 4.2-12.5). Neither BE nor dysplasia recurred at a constant rate. There was a greater probability of recurrence in the first year following CEIM than in the following 4 years combined.

CONCLUSIONS

In this analysis of prospective cohort data from the AIM Dysplasia trial, we found BE to recur after CEIM by RFA in almost one third of patients with baseline dysplastic disease; most recurrences occurred during the first year after CEIM. However, patients who achieved CEIM and remained BE free at 1 year after RFA had a low risk of BE recurrence. Studies are needed to determine when surveillance can be decreased or discontinued; our study did not identify any BE or dysplasia recurrence after 4 years of surveillance.

Editorial: The Effect of Bias on Estimation of Improved Survival After Diagnosis of Barrett's Esophagus

Adjustments for lead and length time bias has been used when examining apparent survival advantages from screening procedures. However, these estimates depend on several assumptions and are modeled from malignancies that are fairly common and large cohorts are available. In smaller retrospective cohorts, adjustments themselves may be based on estimates that may not be biological nor statistically accurate, which can lead to divergent results as has been found in several recent studies of screening in Barrett's esophagus. Only a prospective randomized controlled trial can really determine the benefit though this may not feasible.

Recent Advances in Endoscopy

In this narrative review, invited by the Editors of Gastroenterology, we summarize recent advances in the field of gastrointestinal endoscopy. We have chosen articles published primarily in the past 2-3 years. Although a thorough literature review was performed for each topic, the nature of the article is subjective and systematic and is based on the authors' experience and expertise regarding articles we believed were most likely to be of high clinical and scientific importance.

Radiofrequency Ablation of Barrett's Esophagus: Efficacy, Complications, and Durability

In the last decade, radiofrequency ablation in combination with endoscopic mucosal resection has simplified and improved the treatment of Barrett's esophagus. These treatments not only reduced the progression of dysplastic Barrett's esophagus to esophageal adenocarcinoma but also decreased treatment-related complications. More recent data from larger series with extended follow-up periods are emerging to refine expectations in patients treated with radiofrequency ablation. Although most patients achieve eradication of neoplasia and intestinal metaplasia, in the long-term a substantial portion of patients develop recurrent disease. This article provides an updated review of radiofrequency ablation efficacy, complications, and durability.

Remote malignant intravascular thrombi: EUS-guided FNA diagnosis and impact on cancer staging

BACKGROUND AND AIMS

Malignant vascular invasion usually results from gross direct infiltration from a primary tumor and impacts cancer staging, prognosis, and therapy. However, patients may also develop a remote malignant thrombi (RMT), defined as a malignant intravascular thrombus located remote and noncontiguous to the primary tumor. Our aim was to compare EUS, CT, and magnetic resonance imaging (MRI) findings of RMT and to explore the potential impact on cancer staging.

METHODS

Patients with RMT were identified from a prospectively maintained EUS database. Retrospective chart review was performed to obtain EUS, CT/MRI, clinical, and outcome data.

RESULTS

A median of 3 FNAs (range, 1-8) was obtained from RMT in 17 patients (60 ± 14.1 years, 56% men) between April 2003 and August 2016, with the finding of malignant cytology in 12 patients (70.6%; 10 positive, 2 suspicious). CT/MRI detected the RMT in 5 patients (29.4%), 4 of whom had positive or suspicious EUS-FNA cytology. Among the 8 newly diagnosed pancreatic adenocarcinoma (PaC) patients, CT did not detect the RMT in 5 (63%), of whom 3 patients had positive or suspicious intravascular EUS-FNA cytology. For newly diagnosed PaC patients (n = 8), the EUS-FNA diagnosis of a biopsy specimen-proven RMT upstaged 3 patients (37.5%) and converted 2 patients (25%) from CT resectable to unresectable disease. No adverse events were reported. The mean follow-up was 18.9 ± 27.7 months.

CONCLUSIONS

Our study demonstrates the ability and potential safety of intravascular FNA to detect radiographically occult RMT, which substantially impacts cancer staging and resectability.

Prognostic utility of neuroinjury biomarkers in post out-of-hospital cardiac arrest (OHCA) patient management

Despite aggressive intervention, patients who survive an out-of-hospital cardiac arrest (OHCA) generally have very poor prognoses, with nationwide survival rates of approximately 10-20%. Approximately 90% of survivors will have moderate to severe neurological injury ranging from moderate cognitive impairment to brain death. Currently, few early prognostic indicators are considered reliable enough to support patients' families and clinicians' in their decisions regarding medical futility. Blood biomarkers of neurological injury after OHCA may be of prognostic value in these cases. When most bodily tissues are oxygen-deprived, cellular metabolism switches from aerobic to anaerobic respiration. Neurons are a notable exception, however, being dependent solely upon aerobic respiration. Thus, after several minutes without circulating oxygen, neurons sustain irreversible damage, and certain measurable biomarkers are released into the circulation. Prior studies have demonstrated value in blood biomarkers in prediction of survival and neurologic impairment after OHCA. We hypothesize that understanding peptide biomarker kinetics in the early return of spontaneous circulation (ROSC) period, especially in the setting of refractory cardiac arrest, may assist clinicians in determining prognosis earlier in acute resuscitation. Specifically, during and after immediate resuscitation and return of ROSC, clinicians and families face a series of important questions regarding patient prognosis, futility of care and allocation of scarce resources such as the early initiation of extracorporeal cardiopulmonary resuscitation (ECPR). The ability to provide early prognostic information in this setting is highly valuable. Currently available, as well as potential biomarkers that could be good candidates in prognostication of neurological outcomes after OHCA or in the setting of refractory cardiac arrest will be reviewed and discussed.

Simulation Research in Gastrointestinal and Urologic Care-Challenges and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases and National Institute of Biomedical Imaging and Bioengineering Workshop

A workshop on ''Simulation Research in Gastrointestinal and Urologic Care: Challenges and Opportunities'' was held at the National Institutes of Health in June 2016. The purpose of the workshop was to examine the extent to which simulation approaches have been used by skilled proceduralists (not trainees) caring for patients with gastrointestinal and urologic diseases. The current status of research findings in the use and effectiveness of simulation applications was reviewed, and numerous knowledge gaps and research needs were identified by the faculty and the attendees. The paradigm of ''deliberate practice,'' rather than mere repetition, and the value of coaching by experts was stressed by those who have adopted simulation in music and sports. Models that are most useful for the adoption of simulation by expert clinicians have yet to be fully validated. Initial studies on the impact of simulation on safety and error reduction have demonstrated its value in the training domain, but the role of simulation as a strategy for increased procedural safety remains uncertain in the world of the expert practitioner. Although the basic requirements for experienced physicians to acquire new skills have been explored, the widespread availability of such resources is an unrealized goal, and there is a need for well-designed outcome studies to establish the role of simulation in improving the quality of health care.

Screening and Preventive Strategies in Esophagogastric Cancer

Gastric adenocarcinoma, esophageal adenocarcinoma, and esophageal squamous cell carcinoma are among the most prevalent and deadly of malignancies worldwide. Screening and prevention programs will be critical to finally improving outcomes in these diseases. For gastric adenocarcinoma, screening in high-risk populations has significantly reduced mortality. More research is needed on screening high-risk individuals in low-risk populations. For esophageal adenocarcinoma, work is needed to develop efficient and effective techniques in mass screening programs. For most Western populations, current screening is not cost effective. Avoiding environmental risk factors is critical to reducing the incidence of this deadly illness.

Endoscopic Ultrasound Fine-Needle Aspiration Diagnosis of Synchronous Primary Pancreatic Adenocarcinoma and Effects on Staging and Resectability

Synchronous primary pancreatic adenocarcinoma, defined as the simultaneous presence of 2 or more newly identified and anatomically separate primary adenocarcinomas within the pancreas, is reported rarely. We compared endoscopic ultrasound (EUS) and computed tomography (CT) and magnetic resonance imaging (MRI) findings from patients with synchronous primary pancreatic adenocarcinoma and their effects on cancer staging and treatment. We performed a retrospective analysis of the EUS database at the Mayo Clinic, from September 2008 through May 2016, to collect EUS, CT, MRI, and clinical data from patients with synchronous primary pancreatic adenocarcinoma. EUS and separate fine-needle aspiration of both tumors detected synchronous primary pancreatic adenocarcinoma in 11 patients (70.9 ± 10.4 y; 64% men). Of the 22 cancers, CT (n = 9) and MRI (n = 2) detected 9 (41%) cancers; in only 2 patients did CT detect both cancers. EUS increased cancer stage for 7 of the 11 (64%) patients and changed the status from resectable to unresectable for 3 of the 9 (33%) patients, compared with CT or MRI. EUS findings altered the likely extent of surgical resection for 3 patients. Synchronous primary pancreatic adenocarcinoma is reported rarely and may be undetected by CT or MRI; this could account for the false presumption of early tumor recurrence, rather than actual residual second tumor, leading to incomplete resection.

Prevalence and Predictors of Gastroesophageal Reflux Complications in Community Subjects

BACKGROUND

Predictors of erosive esophagitis (EE) and Barrett's esophagus (BE) and the influence of number of risk factors in the community are not well defined.

METHODS

Rates of BE and EE among community residents identified in a randomized screening trial were defined. The risk of EE and BE associated with single and multiple risk factors (gender, age, GERD, Caucasian ethnicity, ever tobacco use, excess alcohol use, family history of BE or EAC, and central obesity) was analyzed.

RESULTS

Sixty-eight (33 %) of 205 subjects had EE and/or BE. BE prevalence was 7.8 % with dysplasia present in 1.5 %. Rates were comparable between subjects with and without GERD. Male sex and central obesity were independent risk factors. The odds of EE or BE were 3.7 times higher in subjects with three or four risk factors and 5.7 times higher in subjects with five or more risk factors compared with those with two or less factors.

CONCLUSIONS

EE and BE are prevalent in the community regardless of the presence of GERD. Risk appeared to be additive, increasing substantially with three or more risk factors.

Screening for Barrett's esophagus

Barrett's esophagus is the only known esophageal precursor for the development of esophageal adenocarcinoma. However, screening for Barrett's esophagus remains controversial. Although screening is advocated in selected populations, it is unclear how it should be implemented. In this review, the current definition of Barrett's esophagus will be discussed. There will be a review of the emerging evidence supporting the cost-effectiveness of screening and surveillance for Barrett's esophagus in preventing esophageal adenocarcinoma. The known risk factors for Barrett's esophagus and the development of esophageal adenocarcinoma, currently utilized to determine the appropriate populations to screen, will be reviewed. Finally we will review the standard techniques utilized to screen for Barrett's esophagus and examine new technologies that might improve the efficacy and availability of Barrett's esophagus screening.

Systematic review with meta-analysis: prevalent vs. incident oesophageal adenocarcinoma and high-grade dysplasia in Barrett's oesophagus

BACKGROUND

The proportion of oesophageal adenocarcinoma that is detected concurrently with initial Barrett's oesophagus diagnosis is not well studied.

AIM

To compare the proportion of prevalent adenocarcinoma vs. incident adenocarcinoma found during surveillance of Barrett's.

METHODS

We performed a systematic search of MEDLINE, EMBASE and Web of Science (from their inception to 31 May 2015) for cohort studies in adults with Barrett's (nondysplastic Barrett's ± Barrett's with low-grade dysplasia) with minimum average follow-up of 3 years, and providing numbers of prevalent adenocarcinoma detected (concurrently with Barrett's diagnosis and up to 1 year afterwards) vs. incident adenocarcinoma detected (greater than 1 year after Barrett's diagnosis). Pooled weighted proportions of prevalent and incident adenocarcinoma were calculated, using a random effects model.

RESULTS

On meta-analysis of 13 studies reporting on 603 adenocarcinomas in 9657 Barrett's patients, 85.1% of adenocarcinomas were classified as prevalent [95% confidence interval (CI), 78.1-90.2%) and 14.9% as incident (95% CI, 9.8-21.9%), with substantial heterogeneity (I(2) = 66%). Among nine studies reporting on 787 high-grade dysplasia and oesophageal adenocarcinomas in 8098 Barrett's patients, the proportion of prevalent high-grade dysplasia-oesophageal adenocarcinoma was similar at 80.5% (95% CI, 68.1-88.8%, I(2) = 87%). These results remained stable across multiple subgroup analyses including study quality, setting, duration of follow-up and presence of baseline dysplasia.

CONCLUSIONS

In our meta-analysis, four of five patients diagnosed with adenocarcinoma or high-grade dysplasia at index endoscopy or within 1 year of Barrett's follow-up were considered to be prevalent cases. Continued efforts are needed to identify patients with Barrett's before the development of adenocarcinoma.

Risk of recurrence of Barrett's esophagus after successful endoscopic therapy

BACKGROUND AND AIMS

Previous estimates of incidence of intestinal metaplasia (IM) recurrence after achieving complete remission of IM (CRIM) through endoscopic therapy of Barrett's esophagus (BE) have varied widely. We performed a systematic review and meta-analysis of studies to estimate an accurate recurrence risk after CRIM.

METHODS

We performed a systematic search of multiple literature databases through June 2015 to identify studies reporting long-term follow-up after achieving CRIM through endoscopic therapy. Pooled incidence rate (IR) of recurrent IM, dysplastic BE, and high-grade dysplasia (HGD)/esophageal adenocarcinoma (EAC) per person-year of follow-up after CRIM was estimated. Factors associated with recurrence were also assessed.

RESULTS

We identified 41 studies that reported 795 cases of recurrence in 4443 patients over 10,427 patient-years of follow-up. This included 21 radiofrequency ablation studies that reported 603 cases of IM recurrence in 3186 patients over 5741 patient-years of follow-up. Pooled IRs of recurrent IM, dysplastic BE, and HGD/EAC after radiofrequency ablation were 9.5% (95% CI, 6.7-12.3), 2.0% (95% CI, 1.3-2.7), and 1.2% (95% CI, .8-1.6) per patient-year, respectively. When all endoscopic modalities were included, pooled IRs of recurrent IM, dysplastic BE, and HGD/EAC were 7.1% (95% CI, 5.6-8.6), 1.3% (95% CI, .8-1.7), and .8% (95% CI, .5-1.1) per patient-year, respectively. Substantial heterogeneity was noted. Increasing age and BE length were predictive of recurrence; 97% of recurrences were treated endoscopically.

CONCLUSIONS

The incidence of recurrence after achieving CRIM through endoscopic therapy was substantial. A small minority of recurrences were dysplastic BE and HGD/EAC. Hence, continued surveillance after CRIM is imperative. Additional studies with long-term follow-up are needed.

Comparative diagnostic performance of volumetric laser endomicroscopy and confocal laser endomicroscopy in the detection of dysplasia associated with Barrett's esophagus

BACKGROUND AND AIMS

Probe-based confocal laser endomicroscopy (pCLE) and volumetric laser endomicroscopy (VLE) (also known as frequency domain optical coherence tomography) are advanced endoscopic imaging modalities that may be useful in the diagnosis of dysplasia associated with Barrett's esophagus (BE). We performed pCLE examination in ex-vivo EMR specimens and compared the diagnostic performance of using the current VLE scoring index (previously established as OCT-SI) and a novel VLE diagnostic algorithm (VLE-DA) for the detection of dysplasia.

METHODS

A total of 27 patients with BE enrolled in a surveillance program at a tertiary-care center underwent 50 clinically indicated EMRs that were imaged with VLE and pCLE and classified into neoplastic (N = 34; high-grade dysplasia, intramucosal adenocarcinoma) and nonneoplastic (N = 16; low-grade dysplasia, nondysplastic BE), based on histology. Image datasets (VLE, N = 50; pCLE, N = 50) were rated by 3 gastroenterologists trained in the established diagnostic criteria for each imaging modality as well as a new diagnostic algorithm for VLE derived from a training set that demonstrated association of specific VLE features with neoplasia. Sensitivity, specificity, and diagnostic accuracy were assessed for each imaging modality and diagnostic criteria.

RESULTS

The sensitivity, specificity, and diagnostic accuracy of pCLE for detection of BE dysplasia was 76% (95% confidence interval [CI], 59-88), 79% (95% CI, 53-92), and 77% (95% CI, 72-82), respectively. The optimal diagnostic performance of OCT-SI showed a sensitivity of 70% (95% CI, 52-84), specificity of 60% (95% CI, 36-79), and diagnostic accuracy of 67%; (95% CI, 58-78). The use of the novel VLE-DA showed a sensitivity of 86% (95% CI, 69-96), specificity of 88% (95% CI, 60-99), and diagnostic accuracy of 87% (95% CI, 86-88). The diagnostic accuracy of using the new VLE-DA criteria was significantly superior to the current OCT-SI (P < .01).

CONCLUSION

The use of a new VLE-DA showed enhanced diagnostic performance for detecting BE dysplasia ex vivo compared with the current OCT-SI. Further validation of this algorithm in vivo is warranted.

Magnitude of Missed Esophageal Adenocarcinoma After Barrett's Esophagus Diagnosis: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

A proportion of patients with Barrett's esophagus (BE) are diagnosed with esophageal adenocarcinoma (EAC) within 1 year of an endoscopic examination that produced negative findings. These cases of missed cancers have not been well studied, despite current surveillance strategies for BE. We performed a systematic review and meta-analysis to determine the magnitude of missed EAC in cohorts of patients with BE.

METHODS

We searched MEDLINE, EMBASE, and Web of Science from their inception to May 31, 2015 to identify cohort studies of adults with BE (baseline nondysplastic BE ± BE with low-grade dysplasia) and at least a 3-year follow-up period, providing data on missed and incident EACs (diagnosed within 1 year and diagnosed more than 1 year after the initial endoscopy in which BE was diagnosed, respectively). The main outcome measure was pooled proportion of missed and incident EACs (of all EACs detected after initial endoscopy) among BE cohorts, using a random effects model.

RESULTS

In a meta-analysis of 24 studies reporting on 820 missed and incident EACs, 25.3% were classified as missed (95% confidence interval: 16.4%-36.8%) and 74.7% as incident EACs (95% CI: 63.2%-83.6%), although there was substantial heterogeneity among studies (I2 = 74%). When the analysis was restricted to nondysplastic BE cohorts (15 studies), 23.9% of EACs were classified as missed (95% confidence interval: 15.3%-35.4%; I2 = 0%). In a meta-analysis of 10 studies with follow-up periods of ≥5 years (a total of 239 EACs), 22.0% were classified as missed (95% confidence interval: 8.7%-45.5%), with substantial heterogeneity (I2 = 68%).

CONCLUSIONS

Among adults with nondysplastic BE (or BE with low-grade dysplasia) at their index endoscopy and at least a 3-year follow-up period, 25% of EACs are diagnosed within 1 year after the index endoscopy. Additional resources should be allocated to detect missed EAC.

Diagnosing gastrointestinal illnesses using fecal headspace volatile organic compounds

Volatile organic compounds (VOCs) emitted from stool are the components of the smell of stool representing the end products of microbial activity and metabolism that can be used to diagnose disease. Despite the abundance of hydrogen, carbon dioxide, and methane that have already been identified in human flatus, the small portion of trace gases making up the VOCs emitted from stool include organic acids, alcohols, esters, heterocyclic compounds, aldehydes, ketones, and alkanes, among others. These are the gases that vary among individuals in sickness and in health, in dietary changes, and in gut microbial activity. Electronic nose devices are analytical and pattern recognition platforms that can utilize mass spectrometry or electrochemical sensors to detect these VOCs in gas samples. When paired with machine-learning and pattern recognition algorithms, this can identify patterns of VOCs, and thus patterns of smell, that can be used to identify disease states. In this review, we provide a clinical background of VOC identification, electronic nose development, and review gastroenterology applications toward diagnosing disease by the volatile headspace analysis of stool.

Inhibition of Notch signaling enhances transdifferentiation of the esophageal squamous epithelium towards a Barrett's-like metaplasia via KLF4

Barrett's esophagus (BE) is defined as an incomplete intestinal metaplasia characterized generally by the presence of columnar and goblet cells in the formerly stratified squamous epithelium of the esophagus. BE is known as a precursor for esophageal adenocarcinoma. Currently, the cell of origin for human BE has yet to be clearly identified. Therefore, we investigated the role of Notch signaling in the initiation of BE metaplasia. Affymetrix gene expression microarray revealed that BE samples express decreased levels of Notch receptors (NOTCH2 and NOTCH3) and one of the the ligands (JAG1). Furthermore, BE tissue microarray showed decreased expression of NOTCH1 and its downstream target HES1. Therefore, Notch signaling was inhibited in human esophageal epithelial cells by expression of dominant-negative-Mastermind-like (dnMAML), in concert with MYC and CDX1 overexpression. Cell transdifferentiation was then assessed by 3D organotypic culture and evaluation of BE-lineage specific gene expression. Notch inhibition promoted transdifferentiation of esophageal epithelial cells toward columnar-like cells as demonstrated by increased expression of columnar keratins (K8, K18, K19, K20) and glandular mucins (MUC2, MUC3B, MUC5B, MUC17) and decreased expression of squamous keratins (K5, K13, K14). In 3D culture, elongated cells were observed in the basal layer of the epithelium with Notch inhibition. Furthermore, we observed increased expression of KLF4, a potential driver of the changes observed by Notch inhibition. Interestingly, knockdown of KLF4 reversed the effects of Notch inhibition on BE-like metaplasia. Overall, Notch signaling inhibition promotes transdifferentiation of esophageal cells toward BE-like metaplasia in part via upregulation of KLF4. These results support a novel mechanism through which esophageal epithelial transdifferentiation promotes the evolution of BE.

Radiofrequency Ablation Is Associated With Decreased Neoplastic Progression in Patients With Barrett's Esophagus and Confirmed Low-Grade Dysplasia

BACKGROUND & AIMS

Barrett's esophagus (BE) with low-grade dysplasia (LGD) can progress to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) has been shown to be an effective treatment for LGD in clinical trials, but its effectiveness in clinical practice is unclear. We compared the rate of progression of LGD after RFA with endoscopic surveillance alone in routine clinical practice.

METHODS

We performed a retrospective study of patients who either underwent RFA (n = 45) or surveillance endoscopy (n = 125) for LGD, confirmed by at least 1 expert pathologist, from October 1992 through December 2013 at 3 medical centers in the United States. Cox regression analysis was used to assess the association between progression and RFA.

RESULTS

Data were collected over median follow-up periods of 889 days (interquartile range, 264-1623 days) after RFA and 848 days (interquartile range, 322-2355 days) after surveillance endoscopy (P = .32). The annual rates of progression to HGD or EAC were 6.6% in the surveillance group and 0.77% in the RFA group. The risk of progression to HGD or EAC was significantly lower among patients who underwent RFA than those who underwent surveillance (adjusted hazard ratio = 0.06; 95% confidence interval: 0.008-0.48).

CONCLUSIONS

Among patients with BE and confirmed LGD, rates of progression to a combined end point of HGD and EAC were lower among those treated with RFA than among untreated patients. Although selection bias cannot be excluded, these findings provide additional evidence for the use of endoscopic ablation therapy for LGD.

Inter-Observer Agreement among Pathologists Using Wide-Area Transepithelial Sampling With Computer-Assisted Analysis in Patients With Barrett's Esophagus

OBJECTIVES

The histopathological diagnosis of Barrett's esophagus (BE)-associated dysplasia has poor inter-observer agreement. The wide-area transepithelial sampling (WATS) procedure uses a minimally invasive brush biopsy technique for acquiring wide-area sampling of BE tissue followed by computer-assisted analysis. In this study, our aim was to assess inter-observer agreement among pathologists in the diagnosis of Barrett's-associated dysplasia using the WATS computer-assisted analysis technique.

METHODS

WATS slides with varying degrees of BE dysplasia were randomly selected and distributed to four pathologists. Each pathologist graded the slides as nondysplastic, low-grade dysplasia (LGD), or high-grade dysplasia/esophageal adenocarcinoma (HGD/EAC) and completed a standardized case report form (CRF) for each slide.

RESULTS

In all, 149 BE slides were evaluated in a blinded manner by 4 pathologists. The slides included the following: no dysplasia (n=109), LGD, and HGD/EAC (n=40). The overall mean kappa value for all 3 diagnoses for the 4 observers was calculated at 0.86 (95% confidence interval (CI) 0.75-0.97). The kappa values (95% CI) for HGD/EAC, IND/LGD, and no dysplasia were 0.95 (0.88-0.99), 0.74 (0.61-0.85), and 0.88 (0.81-0.94), respectively.

CONCLUSIONS

The diagnosis of BE and associated dysplasia using the WATS technique has very high inter-observer agreement. This appears to be significantly higher as compared with previously published data using standard histopathology.

Use of probe-based confocal laser endomicroscopy (pCLE) in gastrointestinal applications. A consensus report based on clinical evidence

BACKGROUND

Probe-based confocal laser endomicroscopy (pCLE) provides microscopic imaging during an endoscopic procedure. Its introduction as a standard modality in gastroenterology has brought significant progress in management strategies, affecting many aspects of clinical care and requiring standardisation of practice and training.

OBJECTIVE

This study aimed to provide guidance on the standardisation of its practice and training in Barrett's oesophagus, biliary strictures, colorectal lesions and inflammatory bowel diseases.

METHODS

Initial statements were developed by five group leaders, based on the available clinical evidence. These statements were then voted and edited by the 26 participants, using a modified Delphi approach. After two rounds of votes, statements were validated if the threshold of agreement was higher than 75%.

RESULTS

Twenty-six experts participated and, among a total of 77 statements, 61 were adopted (79%) and 16 were rejected (21%). The adoption of each statement was justified by the grade of evidence.

CONCLUSION

pCLE should be used to enhance the diagnostic arsenal in the evaluation of these indications, by providing microscopic information which improves the diagnostic performance of the physician. In order actually to implement this technology in the clinical routine, and to ensure good practice, standardised initial and continuing institutional training programmes should be established.

Ligand-Induced Proton Transfer and Low-Barrier Hydrogen Bond Revealed by X-ray Crystallography

Ligand binding can change the pKa of protein residues and influence enzyme catalysis. Herein, we report three ultrahigh resolution X-ray crystal structures of CTX-M β-lactamase, directly visualizing protonation state changes along the enzymatic pathway: apo protein at 0.79 Å, precovalent complex with nonelectrophilic ligand at 0.89 Å, and acylation transition state (TS) analogue at 0.84 Å. Binding of the noncovalent ligand induces a proton transfer from the catalytic Ser70 to the negatively charged Glu166, and the formation of a low-barrier hydrogen bond (LBHB) between Ser70 and Lys73, with a length of 2.53 Å and the shared hydrogen equidistant from the heteroatoms. QM/MM reaction path calculations determined the proton transfer barrier to be 1.53 kcal/mol. The LBHB is absent in the other two structures although Glu166 remains neutral in the covalent complex. Our data represents the first X-ray crystallographic example of a hydrogen engaged in an enzymatic LBHB, and demonstrates that desolvation of the active site by ligand binding can provide a protein microenvironment conducive to LBHB formation. It also suggests that LBHBs may contribute to stabilization of the TS in general acid/base catalysis together with other preorganized features of enzyme active sites. These structures reconcile previous experimental results suggesting alternatively Glu166 or Lys73 as the general base for acylation, and underline the importance of considering residue protonation state change when modeling protein-ligand interactions. Additionally, the observation of another LBHB (2.47 Å) between two conserved residues, Asp233 and Asp246, suggests that LBHBs may potentially play a special structural role in proteins.

Impact of celiac neurolysis on survival in patients with pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) often produces pain that is difficult to control. Celiac neurolysis (CN) is performed with the goal of improving pain control and quality of life while reducing opioid-related side effects.

OBJECTIVE

We aimed to evaluate whether CN provides a survival advantage for PC patients.

DESIGN

Retrospective case-control study.

SETTING

Single tertiary-care referral center.

PATIENTS

Review of a prospectively maintained database identified patients with unresectable PC who underwent CN over a 12-year period. Each patient was matched to 2 control patients with unresectable PC.

INTERVENTION

CN, which included both celiac plexus neurolysis (CPN) and celiac ganglia neurolysis (CGN).

MAIN OUTCOME MEASUREMENTS

Median survival in Kaplan-Meier curves and hazard ratios.

RESULTS

A total of 417 patients underwent CN and were compared with 840 controls with PC. Baseline characteristics were similar except the CN group had greater weight loss and pain requiring opioids. A mean of 16.6 ± 5.8 mL of alcohol was administered. For patients who underwent CN, the median survival from the time of presentation was shorter compared with controls (193 vs 246 days; hazard ratio 1.32; 95% confidence interval, 1.13-1.54). There was no difference in survival with unilateral or bilateral injection. However, EUS-guided CN was associated with longer survival compared with non-EUS approaches, and those who received CPN had longer survival compared with CGN.

LIMITATIONS

Single center, retrospective.

CONCLUSION

Our study suggests that CN is an independent predictor of shortened survival in PC patients. A prospective study is needed to verify the findings and determine whether shortened survival results from CN or from other features such as performance status and tumor-related characteristics. It is also imperative to verify our finding that EUS-guided CN provides a survival advantage over other approaches and whether CPN prolongs survival compared with CGN.

Molecular pathogenesis of Barrett esophagus: current evidence

This article focuses on recent findings on the molecular mechanisms involved in esophageal columnar metaplasia. Signaling pathways and their downstream targets activate specific transcription factors leading to the expression of columnar and the more specific intestinal-type of genes, which gives rise to Barrett metaplasia. Several animal models have been generated to validate and study these distinct molecular pathways but also to identify the Barrett progenitor cell. Currently, the many aspects involved in the development of esophageal metaplasia that have been elucidated can serve to develop novel molecular therapies to improve treatment or prevent metaplasia. Nevertheless, several key events are still poorly understood and require further investigation.

EUS-derived criteria for distinguishing benign from malignant metastatic solid hepatic masses

BACKGROUND

Detection of hepatic metastases during EUS is an important component of tumor staging.

OBJECTIVE

To describe our experience with EUS-guided FNA (EUS-FNA) of solid hepatic masses and derive and validate criteria to help distinguish between benign and malignant hepatic masses.

DESIGN

Retrospective study, survey.

SETTING

Single, tertiary-care referral center.

PATIENTS

Medical records were reviewed for all patients undergoing EUS-FNA of solid hepatic masses over a 12-year period.

INTERVENTIONS

EUS-FNA of solid hepatic masses.

MAIN OUTCOME MEASUREMENTS

Masses were deemed benign or malignant according to predetermined criteria. EUS images from 200 patients were used to create derivation and validation cohorts of 100 cases each, matched by cytopathologic diagnosis. Ten expert endosonographers blindly rated 15 initial endosonographic features of each of the 100 images in the derivation cohort. These data were used to derive an EUS scoring system that was then validated by using the validation cohort by the expert endosonographer with the highest diagnostic accuracy.

RESULTS

A total of 332 patients underwent EUS-FNA of a hepatic mass. Interobserver agreement regarding the initial endosonographic features among the expert endosonographers was fair to moderate, with a mean diagnostic accuracy of 73% (standard deviation 5.6). A scoring system incorporating 7 EUS features was developed to distinguish benign from malignant hepatic masses by using the derivation cohort with an area under the receiver operating curve (AUC) of 0.92; when applied to the validation cohort, performance was similar (AUC 0.86). The combined positive predictive value of both cohorts was 88%.

LIMITATIONS

Single center, retrospective, only one expert endosonographer deriving and validating the EUS criteria.

CONCLUSION

An EUS scoring system was developed that helps distinguish benign from malignant hepatic masses. Further study is required to determine the impact of these EUS criteria among endosonographers of all experience.

Detection of peritoneal carcinomatosis by EUS fine-needle aspiration: impact on staging and resectability (with videos)

BACKGROUND

Peritoneal carcinomatosis (PC) greatly affects cancer staging and resectability.

OBJECTIVE

To compare the PC detection rate by using EUS and noninvasive imaging and to determine the impact on staging and resectability.

DESIGN

Retrospective study.

SETTING

Single tertiary-care referral center.

PATIENTS

A prospectively maintained EUS database was reviewed to identify patients who underwent EUS-guided FNA (EUS-FNA) of a peritoneal anomaly. Findings were compared with a strict criterion standard that incorporated cytohistologic, radiologic, and clinical data.

INTERVENTION

EUS-FNA of a peritoneal anomaly.

MAIN OUTCOME MEASUREMENTS

Safety and diagnostic yield.

RESULTS

Of 106 patients, a criterion standard was available in 98 (39 female patients; median age, 65 years). The sensitivity, specificity, and accuracy of EUS-FNA versus CT/magnetic resonance imaging (MRI) was 91% versus 28%, 100% versus 85%, and 94% versus 47%, respectively. In newly diagnosed cancer patients, peritoneal FNA upstaged 17 patients (23.6%). Of 32 patients deemed resectable by pre-EUS CT/MRI, 15 (46.9%) were deemed unresectable based solely on peritoneal FNA. The odds of FNA changing the resectability status remained highly significant after adjustment for cancer type, time between CT/MRI and EUS-FNA, and the quality of CT/MRI. The malignant appearance of the peritoneal anomaly but not the presence of ascites on EUS predicted a positive FNA finding (odds ratio 2.56; 95% confidence interval, 1.23-5.4 and odds ratio 0.83; 95% confidence interval, 0.4-1.8, respectively). There were 3 adverse events among 4 patients. Two of the patients developed abdominal pain and one each hypertensive urgency and pancreatitis.

LIMITATIONS

Retrospective design, single-center, bias toward EUS as a diagnostic test.

CONCLUSION

Peritoneal EUS-FNA appears to safely detect radiographically occult PC and improve cancer staging and patient care.

Screening for Barrett's Esophagus

The large increase in the incidence of esophageal adenocarcinoma in the West during the past 30 years has stimulated interest in screening for Barrett's esophagus (BE), a precursor to esophageal cancer. Effective endoscopic treatments for dysplasia and intramucosal cancer, coupled with screening programs to detect BE, could help reverse the increase in the incidence of esophageal cancer. However, there are no accurate, cost-effective, minimally invasive techniques available to screen for BE, reducing the enthusiasm of gastroenterologists. Over the past 5 years, there has been significant progress in the development of screening technologies. We review existing and developing technologies, new minimally invasive imaging techniques, nonendoscopic devices for cell collection, and biomarkers that can be measured in blood or stool samples. We discuss the status of these approaches, data from clinical studies of their effects, and their anticipated strengths and weaknesses in screening. The area is rapidly evolving, and new tools will soon be ready for prime time.