A novel blood-sensing capsule for rapid detection of upper GI bleeding: a prospective clinical trial

BACKGROUND AND AIMS

Upper GI bleeding (UGIB) is a common medical emergency associated with high resource utilization, morbidity, and mortality. Timely EGD can be challenging from personnel, resource, and access perspectives. PillSense (EnteraSense Ltd, Galway, Ireland) is a novel swallowed bleeding sensor for the detection of UGIB, anticipated to aid in patient triage and guide clinical decision-making for individuals with suspected UGIB.

METHODS

This prospective, open-label, single-arm comparative clinical trial of a novel bleeding sensor for patients with suspected UGIB was performed at a tertiary care center. The PillSense system consists of an optical sensor and an external receiver that processes and displays data from the capsule as "Blood Detected" or "No Blood Detected." Patients underwent EGD within 4 hours of capsule administration; participants were followed up for 21 days to confirm capsule passage.

RESULTS

A total of 126 patients were accrued to the study (59.5% male; mean age, 62.4 ± 14.3 years). Sensitivity and specificity for detecting the presence of blood were 92.9% (P = .02) and 90.6% (P < .001), respectively. The capsule's positive and negative predictive values were 74.3% and 97.8%, and positive and negative likelihood ratios were 9.9 and .08. No adverse events or deaths occurred related to the PillSense system, and all capsules were excreted from patients on follow-up.

CONCLUSIONS

The PillSense system is safe and effective for detecting the presence of blood in patients evaluated for UGIB before upper GI endoscopy. It is a rapidly deployed tool, with easy-to-interpret results that will affect the diagnosis and triage of patients with suspected UGIB. (Clinical trial registration number: NCT05385224.).

Physician perceptions on the current and future impact of artificial intelligence to the field of gastroenterology

BACKGROUND AND AIMS

The use of artificial intelligence (AI) has transformative implications to the practice of gastroenterology and endoscopy. The aims of this study were to understand the perceptions of the gastroenterology community toward AI and to identify potential barriers for adoption.

METHODS

A 16-question online survey exploring perceptions on the current and future implications of AI to the field of gastroenterology was developed by the American Society for Gastrointestinal Endoscopy AI Task Force and distributed to national and international society members. Participant demographic information including age, sex, experience level, and practice setting was collected. Descriptive statistics were used to summarize survey findings, and a Pearson χ2 analysis was performed to determine the association between participant demographic information and perceptions of AI.

RESULTS

Of 10,162 invited gastroenterologists, 374 completed the survey. The mean age of participants was 46 years (standard deviation, 12), and 299 participants (80.0%) were men. One hundred seventy-nine participants (47.9%) had >10 years of practice experience, with nearly half working in the community setting. Only 25 participants (6.7%) reported the current use of AI in their clinical practice. Most participants (95.5%) believed that AI solutions will have a positive impact in their practice. One hundred seventy-six participants (47.1%) believed that AI will make clinical duties more technical but will also ease the burden of the electronic medical record (54.0%). The top 3 areas where AI was predicted to be most influential were endoscopic lesion detection (65.3%), endoscopic lesion characterization (65.8%), and quality metrics (32.6%). Participants voiced a desire for education on topics such as the clinical use of AI applications (64.4%), the advantages and limitations of AI applications (57.0%), and the technical methodology of AI (44.7%). Most participants (42.8%) expressed that the cost of AI implementation should be covered by their hospital. Demographic characteristics significantly associated with this perception included participants' years in practice and practice setting.

CONCLUSIONS

Gastroenterologists have an overall positive perception regarding the use of AI in clinical practice but voiced concerns regarding its technical aspects and coverage of costs associated with implementation. Further education on the clinical use of AI applications with understanding of the advantages and limitations appears to be valuable in promoting adoption.

Clinical Outcomes After Endoscopic Management of Low-Risk and High-Risk T1a Esophageal Adenocarcinoma: A Multicenter Study

INTRODUCTION

Endoscopic eradication therapy (EET) is standard of care for T1a esophageal adenocarcinoma (EAC). However, data on outcomes in high-risk T1a EAC are limited. We assessed and compared outcomes after EET of low-risk and high-risk T1a EAC, including intraluminal EAC recurrence, extraesophageal metastases, and overall survival.

METHODS

Patients who underwent EET for T1a EAC at 3 referral Barrett's esophagus endotherapy units between 1996 and 2022 were included. Patients with submucosal invasion, positive deep margins, or metastases at initial diagnosis were excluded. High-risk T1a EAC was defined as T1a EAC with poor differentiation and/or lymphovascular invasion, with low-risk disease being defined without these features. All pathology was systematically assessed by expert gastrointestinal pathologists. Baseline and follow-up endoscopy and pathology data were abstracted. Time-to-event analyses were performed to compare outcomes between groups.

RESULTS

One hundred eighty-eight patients with T1a EAC were included (high risk, n = 45; low risk, n = 143) with a median age of 70 years, and 84% were men. Groups were comparable for age, sex, Barrett's esophagus length, lesion size, and EET technique. Rates of delayed extraesophageal metastases (11.1% vs 1.4%) were significantly higher in the high-risk group ( P = 0.02). There was no significant difference in the rates of intraluminal EAC recurrence ( P = 0.79) and overall survival ( P = 0.73) between the 2 groups.

DISCUSSION

Patients with high-risk T1a EAC undergoing successful EET had a substantially higher rate of extraesophageal metastases compared with those with low-risk T1a EAC on long-term follow-up. These data should be factored into discussions with patients while selecting treatment approaches. Additional prospective data in this area are critical.

Prevalence and Predictors of Barrett's Esophagus After Negative Initial Endoscopy: Analysis From Two National Databases

BACKGROUND & AIMS

Guidelines suggest a single screening esophagogastroduodenoscopy (EGD) in patients with multiple risk factors for Barrett's esophagus (BE). We aimed to determine BE prevalence and predictors on repeat EGD after a negative initial EGD, using 2 large national databases (GI Quality Improvement Consortium [GIQuIC] and TriNetX).

METHODS

Patients who underwent at least 2 EGDs were included and those with BE or esophageal adenocarcinoma detected at initial EGD were excluded. Patient demographics and prevalence of BE on repeat EGD were collected. Multivariate logistic regression was performed to assess for independent risk factors for BE detected on the repeat EGD.

RESULTS

In 214,318 and 153,445 patients undergoing at least 2 EGDs over a median follow-up of 28-35 months, the prevalence of BE on repeat EGD was 1.7% in GIQuIC and 3.4% in TriNetX, respectively (26%-45% of baseline BE prevalence). Most (89%) patients had nondysplastic BE. The prevalence of BE remained stable over time (from 1 to >5 years from negative initial EGD) but increased with increasing number of risk factors. BE prevalence in a high-risk population (gastroesophageal reflux disease plus ≥1 risk factor for BE) was 3%-4%.

CONCLUSIONS

In this study of >350,000 patients, rates of BE on repeat EGD ranged from 1.7%-3.4%, and were higher in those with multiple risk factors. Most were likely missed at initial evaluation, underscoring the importance of a high-quality initial endoscopic examination. Although routine repeat endoscopic BE screening after a negative initial examination is not recommended, repeat screening may be considered in carefully selected patients with gastroesophageal reflux disease and ≥2 risk factors for BE, potentially using nonendoscopic tools.

Population Based Time Trends in the Epidemiology and Mortality of Gastroesophageal Junction and Esophageal Adenocarcinoma

BACKGROUND

Limited data are available on the epidemiology of gastroesophageal junction adenocarcinoma (GEJAC), particularly in comparison to esophageal adenocarcinoma (EAC). With the advent of molecular non-endoscopic Barrett's esophagus (BE) detection tests which sample the esophagus and gastroesophageal junction, early detection of EAC and GEJAC has become a possibility and their epidemiology has gained importance.

AIMS

We sought to evaluate time trends in the epidemiology and survival of patients with EAC and GEJAC in a population-based cohort.

METHODS

EAC and GEJAC patients from 1976 to 2019 were identified using ICD 9 and 10 diagnostic codes from the Rochester Epidemiology Project (REP). Clinical data and survival status were abstracted. Poisson regression was used to calculate incidence rate ratios (IRR). Survival analysis and Cox proportional models were used to assess predictors of survival.

RESULTS

We included 443 patients (287 EAC,156 GEJAC). The incidence of EAC and GEJAC during 1976-2019 was 1.40 (CI 1.1-1.74) and 0.83 (CI 0.61-1.11) per 100,000 people, respectively. There was an increase in the incidence of EAC (IRR = 2.45, p = 0.011) and GEJAC (IRR = 3.17, p = 0.08) from 2000 to 2004 compared to 1995-1999, plateauing in later time periods. Most patients had associated BE and presented at advanced stages, leading to high 5-year mortality rates (66% in EAC and 59% in GEJAC). Age and stage at diagnosis were predictors of mortality.

CONCLUSION

The rising incidence of EAC/GEJAC appears to have plateaued somewhat in the last decade. However, both cancers present at advanced stages with persistently poor survival, underscoring the need for early detection.

Long-term outcomes following successful endoscopic treatment of T1 esophageal adenocarcinoma: a multicenter cohort study

BACKGROUND AND AIMS

Endoscopic eradication therapy (EET) is guideline endorsed for management of early-stage (T1) esophageal adenocarcinoma (EAC). Patients with baseline high-grade dysplasia (HGD) and EAC are at highest risk of recurrence after successful EET, but limited data exist on long-term (>5 year) recurrence outcomes. Our aim was to assess the incidence and predictors of long-term recurrence in a multicenter cohort of patients with T1 EAC treated with EET.

METHODS

Patients with T1 EAC achieving successful endoscopic cancer eradication with a minimum of 5 years' clinical follow-up were included. The primary outcome was neoplastic recurrence, defined as dysplasia or EAC, and it was characterized as early (<2 years), intermediate (2-5 years), or late (>5 years). Predictors of recurrence were assessed by time to event analysis.

RESULTS

A total of 84 T1 EAC patients (75 T1a, 9 T1b) with a median 9.1 years (range, 5.1-18.3 years) of follow-up were included. The overall incidence of neoplastic recurrence was 2.0 per 100 person-years of follow-up. Seven recurrences (3 dysplasia, 4 EAC) occurred after 5 years of EAC remission. Overall, 88% of recurrences were treated successfully endoscopically. EAC recurrence-related mortality occurred in 3 patients at a median of 5.2 years from EAC remission. Complete eradication of intestinal metaplasia was independently associated with reduced recurrence (hazard ratio, .13).

CONCLUSIONS

Following successful EET of T1 EAC, neoplastic recurrence occurred after 5 years in 8.3% of cases. Careful long-term surveillance should be continued in this patient population. Complete eradication of intestinal metaplasia should be the therapeutic end point for EET.

Development of Electronic Health Record-Based Machine Learning Models to Predict Barrett's Esophagus and Esophageal Adenocarcinoma Risk

INTRODUCTION

Screening for Barrett's esophagus (BE) is suggested in those with risk factors, but remains underutilized. BE/esophageal adenocarcinoma (EAC) risk prediction tools integrating multiple risk factors have been described. However, accuracy remains modest (area under the receiver-operating curve [AUROC] ≤0.7), and clinical implementation has been challenging. We aimed to develop machine learning (ML) BE/EAC risk prediction models from an electronic health record (EHR) database.

METHODS

The Clinical Data Analytics Platform, a deidentified EHR database of 6 million Mayo Clinic patients, was used to predict BE and EAC risk. BE and EAC cases and controls were identified using International Classification of Diseases codes and augmented curation (natural language processing) techniques applied to clinical, endoscopy, laboratory, and pathology notes. Cases were propensity score matched to 5 independent randomly selected control groups. An ensemble transformer-based ML model architecture was used to develop predictive models.

RESULTS

We identified 8,476 BE cases, 1,539 EAC cases, and 252,276 controls. The BE ML transformer model had an overall sensitivity, specificity, and AUROC of 76%, 76%, and 0.84, respectively. The EAC ML transformer model had an overall sensitivity, specificity, and AUROC of 84%, 70%, and 0.84, respectively. Predictors of BE and EAC included conventional risk factors and additional novel factors, such as coronary artery disease, serum triglycerides, and electrolytes.

DISCUSSION

ML models developed on an EHR database can predict incident BE and EAC risk with improved accuracy compared with conventional risk factor-based risk scores. Such a model may enable effective implementation of a minimally invasive screening technology.

Optimized Surveillance Intervals Following Endoscopic Eradication of Dysplastic Barrett's Esophagus: An International Cohort Study

BACKGROUND & AIMS

Recommended surveillance intervals after complete eradication of intestinal metaplasia (CE-IM) after endoscopic eradication therapy (EET) are largely not evidence-based. Using recurrence rates in a multicenter international Barrett's esophagus (BE) CE-IM cohort, we aimed to generate optimal intervals for surveillance.

METHODS

Patients with dysplastic BE undergoing EET and achieving CE-IM from prospectively maintained databases at 5 tertiary-care centers in the United States and the United Kingdom were included. The cumulative incidence of recurrence was estimated, accounting for the unknown date of actual recurrence that lies between the dates of current and previous endoscopy. This cumulative incidence of recurrence subsequently was used to estimate the proportion of patients with undetected recurrence for various surveillance intervals over 5 years. Intervals were selected that minimized recurrences remaining undetected for more than 6 months. Actual patterns of post-CE-IM follow-up evaluation are described.

RESULTS

A total of 498 patients (with baseline low-grade dysplasia, 115 patients; high-grade dysplasia [HGD], 288 patients; and intramucosal adenocarcinoma [IMCa], 95 patients) were included. Any recurrence occurred in 27.1% and dysplastic recurrence occurred in 8.4% over a median of 2.6 years of follow-up evaluation. For pre-ablation HGD/IMCa, intervals of 6, 12, 18, and 24 months, and then annually, resulted in no patients with dysplastic recurrence undetected for more than 6 months, comparable with current guideline recommendations despite a 33% reduction in the number of surveillance endoscopies. For pre-ablation low-grade dysplasia, intervals of 1, 2, and 4 years balanced endoscopic burden and undetected recurrence risk.

CONCLUSIONS

Lengthening post-CE-IM surveillance intervals would reduce the endoscopic burden after CE-IM with comparable rates of recurrent HGD/IMCa. Future guidelines should consider reduced surveillance frequency.

Prediction of Progression in Barrett's Esophagus Using a Tissue Systems Pathology Test: A Pooled Analysis of International Multicenter Studies

BACKGROUND & AIMS

Prediction of progression risk in Barrett's esophagus (BE) may enable personalized management. We aimed to assess the adjunct value of a tissue systems pathology test (TissueCypher) performed on paraffin-embedded biopsy tissue, when added to expert pathology review in predicting incident progression, pooling individual patient-level data from multiple international studies METHODS: Demographics, clinical features, the TissueCypher risk class/score, and progression status were analyzed. Conditional logistical regression analysis was used to develop multivariable models predicting incident progression with and without the TissueCypher risk class (low, intermediate, high). Concordance (c-) statistics were calculated and compared with likelihood ratio tests to assess predictive ability of models. A risk prediction calculator integrating clinical variables and TissueCypher risk class was also developed.

RESULTS

Data from 552 patients with baseline no (n = 472), indefinite (n = 32), or low-grade dysplasia (n = 48) (comprising 152 incident progressors and 400 non-progressors) were analyzed. A high-risk test class independently predicted increased risk of progression to high-grade dysplasia/adenocarcinoma (odds ratio, 6.0; 95% confidence interval, 2.9-12.0), along with expert confirmed low-grade dysplasia (odds ratio, 2.9; 95% confidence interval, 1.2-7.2). Model prediction of progression with the TissueCypher risk class incorporated was significantly superior than without, in the whole cohort (c-statistic 0.75 vs 0.68; P < .0001) and the nondysplastic BE subset (c-statistic 0.72 vs 0.63; P < .0001). Sensitivity and specificity of the high risk TissueCypher class were 38% and 94%, respectively.

CONCLUSIONS

An objective tissue systems pathology test high-risk class is a strong independent predictor of incident progression in patients with BE, substantially improving progression risk prediction over clinical variables alone. Although test specificity was high, sensitivity was modest.

Development of a deep learning model for the histologic diagnosis of dysplasia in Barrett's esophagus

BACKGROUND AND AIMS

The risk of progression in Barrett's esophagus (BE) increases with development of dysplasia. There is a critical need to improve the diagnosis of BE dysplasia, given substantial interobserver disagreement among expert pathologists and overdiagnosis of dysplasia by community pathologists. We developed a deep learning model to predict dysplasia grade on whole-slide imaging.

METHODS

We digitized nondysplastic BE (NDBE), low-grade dysplasia (LGD), and high-grade dysplasia (HGD) histology slides. Two expert pathologists confirmed all histology and digitally annotated areas of dysplasia. Training, validation, and test sets were created (by a random 70/20/10 split). We used an ensemble approach combining a "you only look once" model to identify regions of interest and histology class (NDBE, LGD, or HGD) followed by a ResNet101 model pretrained on ImageNet applied to the regions of interest. Diagnostic performance was determined for the whole slide.

RESULTS

We included slides from 542 patients (164 NDBE, 226 LGD, and 152 HGD) yielding 8596 bounding boxes in the training set, 1946 bounding boxes in the validation set, and 840 boxes in the test set. When the ensemble model was used, sensitivity and specificity for LGD was 81.3% and 100%, respectively, and >90% for NDBE and HGD. The overall positive predictive value and sensitivity metric (calculated as F1 score) was .91 for NDBE, .90 for LGD, and 1.0 for HGD.

CONCLUSIONS

We successfully trained and validated a deep learning model to accurately identify dysplasia on whole-slide images. This model can potentially help improve the histologic diagnosis of BE dysplasia and the appropriate application of endoscopic therapy.

Acute Esophageal Necrosis: A Retrospective Cohort Study Highlighting the Mayo Clinic Experience

OBJECTIVE

To describe the clinical, endoscopic, and histologic features in patients with acute esophageal necrosis (AEN).

PATIENTS AND METHODS

In this retrospective cohort study, patients who were diagnosed as having AEN at Mayo Clinic sites in Minnesota, Florida, and Arizona between January 1, 1996, and January 31, 2021, were included. Data were collected on patient clinical characteristics and endoscopic and pathologic findings.

RESULTS

The study included 79 patients with AEN with a median (range) age of 64 years (12 to 91 years); 53 (67.1%) were men. Predominant presenting symptoms were hematemesis (49 of 79 [62.0%]), abdominal pain (29 [36.7%]), and melena (20 [25.3%]). Shock was the triggering event for AEN in 49 (62.0%). The 30- and 90-day mortality were 24.0% (19 of 79) and 31.6% (25), respectively. The presence of coexisting infection or bacteremia was significantly associated with 90-day mortality (P<.01). Endoscopically, involvement of the distal third only, distal two-thirds only, and entire esophagus was observed in 31.6% (24 of 76), 39.5% (30), and 29.0% (22), respectively. The length of esophageal involvement correlated with duration of hospitalization (P=.05). The endoscopic appearance of the esophageal mucosa ranged from predominantly white (21 of 44 [47.7%]) to mixed white and black (13 [29.6%]) to predominantly black (10 [22.7%]), and sloughing was present in 18 (40.9%). In the 26 patients with histopathologic findings available for review, 25 (96.1%) had necrosis and/or ulceration with abundant pigmentation. Among the 79 patients, 39 (49.4%) had a follow-up esophagogastroduodenoscopy; 26 of these 39 patients (66.7%) had resolution while 5 had persistent AEN, 4 of whom had improvement. Esophageal strictures developed in 7 of the 39 patients (18.0%).

CONCLUSION

Acute esophageal necrosis is a serious condition observed in critically ill patients. Its endoscopic appearance can be highly variable. In patients with an unclear diagnosis, esophageal biopsies may be helpful given the characteristic histologic findings.

Artificial intelligence-enhanced volumetric laser endomicroscopy improves dysplasia detection in Barrett's esophagus in a randomized cross-over study

Volumetric laser endomicroscopy (VLE) is an advanced endoscopic imaging tool that can improve dysplasia detection in Barrett’s esophagus (BE). However, VLE scans generate 1200 cross-sectional images that can make interpretation difficult. The impact of a new VLE artificial intelligence algorithm called Intelligent Real-time Image Segmentation (IRIS) is not well-characterized. This is a randomized prospective cross-over study of BE patients undergoing endoscopy who were randomized to IRIS-enhanced or unenhanced VLE first followed by the other (IRIS-VLE vs. VLE-IRIS, respectively) at expert BE centers. The primary outcome was image interpretation time, which served as a surrogate measure for ease of interpretation. The secondary outcome was diagnostic yield of dysplasia for each imaging modality. 133 patients were enrolled. 67 patients were randomized to VLE-IRIS and 66 to IRIS-VLE. Total interpretation time did not differ significantly between groups (7.8 min VLE-IRIS vs. 7 min IRIS-VLE, P = 0.1), however unenhanced VLE interpretation time was significantly shorter in the IRIS-VLE group (2.4 min vs. 3.8 min, P < 0.01). When IRIS was used first, 100% of dysplastic areas were identified, compared with 76.9% when VLE was the first interpretation modality (P = 0.06). IRIS-enhanced VLE reduced the time of subsequent unenhanced VLE interpretation, suggesting heightened efficiency and improved dysplasia detection. It was also able to identify all endoscopically non-visible dysplastic areas.

Feasibility and Safety of Tethered Capsule Endomicroscopy in Patients With Barrett's Esophagus in a Multi-Center Study

BACKGROUND & AIMS

Tethered capsule endomicroscopy (TCE) involves swallowing a small tethered pill that implements optical coherence tomography (OCT) imaging, procuring high resolution images of the whole esophagus. Here, we demonstrate and evaluate the feasibility and safety of TCE and a portable OCT imaging system in patients with Barrett's esophagus (BE) in a multi-center (5-site) clinical study.

METHODS

Untreated patients with BE as per endoscopic biopsy diagnosis were eligible to participate in the study. TCE procedures were performed in unsedated patients by either doctors or nurses. After the capsule was swallowed, the device continuously obtained 10-μm-resolution cross-sectional images as it traversed the esophagus. Following imaging, the device was withdrawn through mouth, and disinfected for subsequent reuse. BE lengths were compared to endoscopy findings when available. OCT-TCE images were compared to volumetric laser endomicroscopy (VLE) images from a patient who had undergone VLE on the same day as TCE.

RESULTS

147 patients with BE were enrolled across all sites. 116 swallowed the capsule (79%), 95/114 (83.3%) men and 21/33 (63.6%) women (P = .01). High-quality OCT images were obtained in 104/111 swallowers (93.7%) who completed the procedure. The average imaging duration was 5.55 ± 1.92 minutes. The mean length of esophagus imaged per patient was 21.69 ± 5.90 cm. A blinded comparison of maximum extent of BE measured by OCT-TCE and EGD showed a strong correlation (r = 0.77-0.79). OCT-TCE images were of similar quality to those obtained by OCT-VLE.

CONCLUSIONS

The capabilities of TCE to be used across multiple sites, be administered to unsedated patients by either physicians or nurses who are not expert in OCT-TCE, and to rapidly and safely evaluate the microscopic structure of the esophagus make it an emerging tool for screening and surveillance of BE patients. Clinical trial registry website and trial number: NCT02994693 and NCT03459339.

Diagnostic performance of volumetric laser endomicroscopy for Barrett's esophagus dysplasia amongst gastroenterology trainees

BACKGROUND

Volumetric laser endomicroscopy (VLE) is an advanced imaging modality used in Barrett's esophagus (BE) surveillance. VLE image interpretation is challenged by subtle grayscale image variation across a large amount of data. Training in VLE interpretation is not standardized. This study aims to determine if VLE training can be incorporated into a gastroenterology (GI) fellowship curriculum with the use of a self-directed module.

METHODS

A standardized, self-directed training module (30 min) was created explaining the background and established VLE criteria for the diagnosis of BE dysplasia. A VLE image dataset was generated from a multicenter VLE database of targeted biopsies. GI trainees were asked to grade each image for the presence or absence of the following criteria (I) increased surface optical frequency domain imaging (OFDI) signal intensity and (II) atypical glands and provide a final diagnosis (dysplastic vs. non-dysplastic). Diagnostic performance was calculated and results compared to VLE expert interpretation using histology as the gold-standard.

RESULTS

The dataset included 50 VLE images (10 high-grade dysplasia, 40 non-dysplastic BE). VLE images were reviewed in a randomized and blinded fashion by 5 GI trainees with no prior VLE experience and 5 experienced VLE users. Sensitivity, specificity and accuracy of GI trainees was 83.3% (95% CI: 71.5-91.7%), 59.0% (95% CI: 51.6-66.0%), and 64.8% (95% CI: 58.5-70.7%) compared to 80.0% (95% CI: 67.7-89.2%), 79.5% (95% CI: 73.0-85.0%), and 79.6% (95% CI: 74.1-84.4%) for VLE experts respectively. The difference in specificity and accuracy between the two groups were statistically significant with P<0.001.

CONCLUSIONS

A brief training session on VLE is inadequate to reach competency in interpretation of VLE by GI trainees. Additional experience is required to accurately interpret VLE images.

Spray cryotherapy prevents need for palliative stenting in patients with esophageal cancer-associated dysphagia

BACKGROUND

Dysphagia is the most common symptom in advanced esophageal cancer patients. Esophageal stent placement (SP) is a common palliation method but can be associated with significant morbidity. Limited data exist regarding the ability of spray cryotherapy (SC) prolong time to SP.

METHODS

A Mayo Clinic (Rochester, MN) patient database was reviewed for cases with a SC indication of esophageal cancer palliation from 2007-2019. Procedures were performed using a liquid nitrogen SC system to apply 2-5 separate 20 second freeze and 60 second thaw cycles based on tumor characteristics. Primary outcome was time to subsequent palliative SP.

RESULTS

Of 56 patients (71.4% male, mean age 77.8 ± 10.2 years) who underwent a total of 199 SC sessions (mean 3.6 ± 2.7, range 1-12 per patient), 41 had adenocarcinoma and 15 squamous cell carcinoma (SCC). Overall, 13 patients underwent subsequent SP within a mean duration of 15.7 ± 11.0 months over a mean follow-up duration of 25.6 ± 29.4 months. Treatment did produce stenosis in 16 patients, who required dilation within a mean period of 193.1 ± 294.1 days; notably, 10 patients had a history of preceding malignant strictures requiring dilation. Two patients experienced bleeding requiring transfusion, whereas 1 experienced perforation at the start of SC. Prior chemotherapy and/or radiation was not associated with developing an SC-related complication (risk ratio (RR) 1.5; 95% CI 0.6-3.7, P > 0.4).

CONCLUSIONS

SC appears to be an effective and safe modality to palliate esophageal cancer in appropriate candidates. Majority of patients who undergo SC avoid the need for future SP. If patients eventually require SP, they are able to, on average, defer stenting for >1 year from SC initiation.

A Practical Guide to the Evaluation of Small Bowel Bleeding

Gastrointestinal bleeding is a common clinical problem encountered in both the inpatient and outpatient settings. Although the evaluation of upper and lower gastrointestinal bleeding is often straightforward, bleeding from the small bowel may pose a clinical challenge. In this article, we review the indications, modalities, and differential diagnoses of small bowel bleeding. On completion of the article, clinicians should be able to identify common causes of small bowel bleeding, understand the advantages and disadvantages of the modalities used to evaluate small bowel bleeding, and enact a stepwise management approach to the patient with presumed small bowel bleeding.

Utilisation of artificial intelligence for the development of an EUS-convolutional neural network model trained to enhance the diagnosis of autoimmune pancreatitis

OBJECTIVE

The diagnosis of autoimmune pancreatitis (AIP) is challenging. Sonographic and cross-sectional imaging findings of AIP closely mimic pancreatic ductal adenocarcinoma (PDAC) and techniques for tissue sampling of AIP are suboptimal. These limitations often result in delayed or failed diagnosis, which negatively impact patient management and outcomes. This study aimed to create an endoscopic ultrasound (EUS)-based convolutional neural network (CNN) model trained to differentiate AIP from PDAC, chronic pancreatitis (CP) and normal pancreas (NP), with sufficient performance to analyse EUS video in real time.

DESIGN

A database of still image and video data obtained from EUS examinations of cases of AIP, PDAC, CP and NP was used to develop a CNN. Occlusion heatmap analysis was used to identify sonographic features the CNN valued when differentiating AIP from PDAC.

RESULTS

From 583 patients (146 AIP, 292 PDAC, 72 CP and 73 NP), a total of 1 174 461 unique EUS images were extracted. For video data, the CNN processed 955 EUS frames per second and was: 99% sensitive, 98% specific for distinguishing AIP from NP; 94% sensitive, 71% specific for distinguishing AIP from CP; 90% sensitive, 93% specific for distinguishing AIP from PDAC; and 90% sensitive, 85% specific for distinguishing AIP from all studied conditions (ie, PDAC, CP and NP).

CONCLUSION

The developed EUS-CNN model accurately differentiated AIP from PDAC and benign pancreatic conditions, thereby offering the capability of earlier and more accurate diagnosis. Use of this model offers the potential for more timely and appropriate patient care and improved outcome.

Neoplasia Detection Rate in Barrett's Esophagus and Its Impact on Missed Dysplasia: Results from a Large Population-Based Database

BACKGROUND & AIMS

It is a challenge to detect dysplasia in Barrett's esophagus (BE) and esophageal adenocarcinomas (EACs) are missed in 25%-33% of cases. The neoplasia detection rate (NDR), defined as the rate of high-grade dysplasia (HGD) or EAC detection during initial surveillance endoscopy, has been proposed as a quality metric for endoscopic evaluation of patients with BE. However, current estimates are from referral center cohorts, which might overestimate NDR. Effects on rates of missed dysplasia are also unknown. We analyzed data from a large cohort of patients with BE to estimate the NDR and factors associated with it, and assess the effects of the NDR on the rate of missed dysplasia.

METHODS

We analyzed data from 1066 patients in the Rochester Epidemiology Project-linked medical record system, a population-based cohort of patients with BE (confirmed by review of the endoscopic and histologic reports) from 11 southeastern Minnesota counties from 1991 through 2019. Biopsies reported to contain dysplasia were confirmed by expert gastrointestinal pathologists. The NDR was calculated as the rate of HGD or EAC detected by histologic analyses of biopsies collected during the first surveillance endoscopy. Patients without HGD or EAC at their initial endoscopy (n = 391) underwent repeat endoscopy within 12 months; HGD or EAC detected at the repeat endoscopy were considered to be missed on index endoscopy. Factors associated with NDR and missed dysplasia were identified using univariate and multivariate logistic regression models.

RESULTS

The NDR was 4.9% (95% CI, 3.8-6.4); 3.1% of patients had HGD, 1.8% had EAC, and 10.6% had low-grade dysplasia. Factors associated with higher rates of detection of neoplasia included older age, male sex, smoking, increasing length of BE, and surveillance endoscopies by gastroenterologists. This NDR was associated with a substantially lower rate of missed dysplasia (13%).

CONCLUSIONS

In an analysis of 1066 patients with BE in a population-based cohort, we found a lower NDR and lower rate of missed dysplasia than previously reported. NDR may have value as a quality metric in BE surveillance if validated in other cohorts.

Prospective development and validation of a volumetric laser endomicroscopy computer algorithm for detection of Barrett's neoplasia

BACKGROUND AND AIMS

Volumetric laser endomicroscopy (VLE) is an advanced imaging modality used to detect Barrett's esophagus (BE) dysplasia. However, real-time interpretation of VLE scans is complex and time-consuming. Computer-aided detection (CAD) may help in the process of VLE image interpretation. Our aim was to train and validate a CAD algorithm for VLE-based detection of BE neoplasia.

METHODS

The multicenter, VLE PREDICT study, prospectively enrolled 47 patients with BE. In total, 229 nondysplastic BE and 89 neoplastic (high-grade dysplasia/esophageal adenocarcinoma) targets were laser marked under VLE guidance and subsequently underwent a biopsy for histologic diagnosis. Deep convolutional neural networks were used to construct a CAD algorithm for differentiation between nondysplastic and neoplastic BE tissue. The CAD algorithm was trained on a set consisting of the first 22 patients (134 nondysplastic BE and 38 neoplastic targets) and validated on a separate test set from patients 23 to 47 (95 nondysplastic BE and 51 neoplastic targets). The performance of the algorithm was benchmarked against the performance of 10 VLE experts.

RESULTS

Using the training set to construct the algorithm resulted in an accuracy of 92%, sensitivity of 95%, and specificity of 92%. When performance was assessed on the test set, accuracy, sensitivity, and specificity were 85%, 91%, and 82%, respectively. The algorithm outperformed all 10 VLE experts, who demonstrated an overall accuracy of 77%, sensitivity of 70%, and specificity of 81%.

CONCLUSIONS

We developed, validated, and benchmarked a VLE CAD algorithm for detection of BE neoplasia using prospectively collected and biopsy-correlated VLE targets. The algorithm detected neoplasia with high accuracy and outperformed 10 VLE experts. (The Netherlands National Trials Registry (NTR) number: NTR 6728.).

Outcomes of radiofrequency ablation by manual versus self-sizing circumferential balloon catheters for the treatment of dysplastic Barrett's esophagus: a multicenter comparative cohort study

BACKGROUND AND AIMS

Radiofrequency ablation (RFA) is the preferred ablative modality for treating dysplastic Barrett's esophagus. The recently introduced self-sizing circumferential ablation catheter eliminates the need for a sizing balloon. Although it enhances efficiency, outcomes have not been compared with the previous manual-sizing catheter. We evaluated the comparative safety and efficacy of these 2 ablation systems in a large, multicenter cohort.

METHODS

Patients undergoing RFA at 3 tertiary care centers from 2005 to 2018 were included. Circumferential RFA was performed in a standard fashion, followed by focal RFA as needed. Outcomes were compared between the self-sizing and manual-sizing groups. The primary outcome was the rate of adverse events, including strictures, perforation, and bleeding. Secondary outcomes were procedure time and treatment efficacy, as assessed by rates and time to complete eradication of dysplasia (CE-D) and intestinal metaplasia (CE-IM).

RESULTS

Three hundred eighteen patients were included, 90 (28.3%) treated with the self-sizing catheter and 228 (71.7%) with the manual-sizing catheter. Twenty-one patients (6.6%) developed strictures (8 [8.9%] in the self-sizing group and 13 [5.7%] in the manual-sizing group, P = .32). Of the self-sizing strictures, 75% occurred at the 12J dose before widespread adoption of the current 10J treatment standard. One patient developed bleeding, and no perforations were encountered. Procedure time was significantly shorter in the self-sizing group. No significant differences were observed in rates of and time to CE-D and CE-IM.

CONCLUSIONS

These findings suggest that both systems are comparable in safety and efficacy. The use of the self-sizing system may enhance the efficiency of RFA for treating dysplastic Barrett's esophagus.

Expert assessment on volumetric laser endomicroscopy full scans in Barrett's esophagus patients with or without high grade dysplasia or early cancer

BACKGROUND

Volumetric laser endomicroscopy (VLE) allows for near-microscopic imaging of the superficial esophageal wall and may improve detection of early neoplasia in Barrett's esophagus (BE). Interpretation of a 6-cm long, circumferential VLE "full scan" may however be challenging for endoscopists. We aimed to evaluate the accuracy of VLE experts in correctly diagnosing VLE full scans of early neoplasia and non-dysplastic BE (NDBE).

METHODS

29 VLE full scan videos (15 neoplastic and 14 NDBE) were randomly evaluated by 12 VLE experts using a web-based module. Experts were blinded to the endoscopic BE images and histology. The 15 neoplastic cases contained a subtle endoscopically visible lesion, which on endoscopic resection showed high grade dysplasia or cancer. NDBE cases had no visible lesions and an absence of dysplasia in all biopsies. VLE videos were first scored as "neoplastic" or "NDBE." If neoplastic, assessors located the area most suspicious for neoplasia. Primary outcome was the performance of VLE experts in differentiating between non-dysplastic and neoplastic full scan videos, calculated by accuracy, sensitivity, and specificity. Secondary outcomes included correct location of neoplasia, interobserver agreement, and level of confidence.

RESULTS

VLE experts correctly labelled 73 % (95 % confidence interval [CI] 67 % - 79 %) of neoplastic VLE videos. In 54 % (range 27 % - 66 %) both neoplastic diagnosis and lesion location were correct. NDBE videos were consistent with endoscopic biopsies in 52 % (95 %CI 46 % - 57 %). Interobserver agreement was fair (kappa 0.28). High level of confidence was associated with a higher rate of correct neoplastic diagnosis (81 %) and lesion location (73 %).

CONCLUSIONS

Identification of subtle neoplastic lesions in VLE full scans by experts was disappointing. Future studies should focus on improving methodologies for reviewing full scans, development of refined VLE criteria for neoplasia, and computer-aided diagnosis of VLE scans.

Longitudinal and Circumferential Distributions of Dysplasia and Early Neoplasia in Barrett's Esophagus: A Pooled Analysis of Three Prospective Studies

INTRODUCTION

Studies have shown that dysplasia in Barrett's esophagus (BE) has a predilection for the right hemisphere. There is limited information on the longitudinal distribution. The aim was to determine both the longitudinal and circumferential distributions of dysplasia and early neoplasia from 3 prospective studies.

METHODS

This is a pooled analysis from 3 prospective studies of patients with treatment-naive BE. Both circumferential and longitudinal locations (for BE segments greater than 1 cm) of dysplastic and early neoplastic lesions were recorded.

RESULTS

A total of 177 dysplastic and early neoplastic lesions from 91 patients were included in the pooled analysis; of which 59.3% (n = 105) were seen on high-definition white light endoscopy, 29.4% (n = 52) on advanced imaging, and 11.2% (n = 20) with random biopsies. The average Prague score was C3M5. Of 157 lesions within BE segments greater than 1 cm, 49 (34.8%) lesions were in the proximal half, whereas 92 lesions (65.2%) were in the distal half (P < 0.001). The right hemisphere of the esophagus contained 55% (86/157) of the total lesions compared with 45% (71/157) for the left hemisphere (P = 0.02). This was because of the presence of high-grade dysplasia being concentrated in the right hemisphere compared with the left hemisphere (60% vs 40%, P = 0.002).

DISCUSSION

In this pooled analysis of prospective studies, both low-grade dysplasia and high-grade dysplasia are more frequently found in the distal half of the Barrett's segment. This study confirms that the right hemisphere is a hot spot for high-grade dysplasia. Careful attention to these locations is important during surveillance endoscopy.

Epidemiology and Outcomes of Young-Onset Esophageal Adenocarcinoma: An Analysis from a Population-Based Database

BACKGROUND

Esophageal adenocarcinoma is a lethal cancer with rising incidence. There are limited data in younger (<50 years) patients with esophageal adenocarcinoma. We aimed to assess time trends in the incidence and outcomes of "young-onset" esophageal adenocarcinoma using a population-based database.

METHODS

We queried the Surveillance, Epidemiology, and End Results 9 database to identify patients with esophageal adenocarcinoma between 1975 and 2015. Patients were stratified into three age strata: <50, 50 to 69, and ≥70 years. Staging was stratified as localized, regional, and distant. Trends in incidence, disease stage, and survival were assessed in three periods (1975-89, 1990-99, and 2000-2015). Univariate and multivariate models were created to identify predictors of mortality.

RESULTS

Esophageal adenocarcinoma incidence has increased in patients <50 years of age, with an annual percentage change of 2.9% (95% confidence interval, 1.4%-4.4%) from 1975 to 2015. Young-onset esophageal adenocarcinoma presented at more advanced stages (regional + distant) compared with older patients (84.9% vs. 67.3%; P < 0.01), with increasing proportion of advanced stages over the study period. These patients also experienced poorer 5-year esophageal adenocarcinoma-free survival compared with older patients (22.9%% vs. 29.6%; P < 0.01), although this finding was attenuated on stage-stratified analysis.

CONCLUSIONS

Young-onset esophageal adenocarcinoma, while uncommon, is rising in incidence. Concerningly, the proportion of advanced disease continues to increase. Young-onset esophageal adenocarcinoma also presents at more advanced stages, resulting in poorer esophageal adenocarcinoma-free survival.

IMPACT

Patients with esophageal adenocarcinoma younger than 50 years present at more advanced stages with higher esophageal adenocarcinoma-specific mortality compared with older peers. Current diagnostic and management strategies for young-onset esophageal adenocarcinoma may need to be reevaluated.

Multicenter study on the diagnostic performance of multiframe volumetric laser endomicroscopy targets for Barrett's esophagus neoplasia with histopathology correlation

Volumetric laser endomicroscopy (VLE) has been shown to improve detection of early neoplasia in Barrett's esophagus (BE). However, diagnostic performance using histopathology-correlated VLE regions of interest (ROIs) has not been adequately studied. We evaluated the diagnostic accuracy of VLE assessors for identification of early BE neoplasia in histopathology-correlated VLE ROIs. In total, 191 ROIs (120 nondysplastic and 71 neoplastic) from 50 BE patients were evaluated in a random order using a web-based module. All ROIs contained histopathology correlations enabled by VLE laser marking. Assessors were blinded to endoscopic BE images and histology. ROIs were first scored as nondysplastic or neoplastic. Level of confidence was assigned to the predicted diagnosis. Outcome measures were: (i) diagnostic performance of VLE assessors for identification of BE neoplasia in all VLE ROIs, defined as accuracy, sensitivity, and specificity; (ii) diagnostic performance of VLE assessors for only high level of confidence predictions; and (iii) interobserver agreement. Accuracy, sensitivity, and specificity for BE neoplasia identification were 79% (confidence interval [CI], 75-83), 75% (CI, 71-79), and 81% (CI, 76-86), respectively. When neoplasia was identified with a high level of confidence, accuracy, sensitivity, and specificity were 88%, 83%, and 90%, respectively. The overall strength of interobserver agreement was fair (k = 0.29). VLE assessors can identify BE neoplasia with reasonable diagnostic accuracy in histopathology-correlated VLE ROIs, and accuracy is enhanced when BE neoplasia is identified with high level of confidence. Future work should focus on renewed VLE image reviewing criteria and real-time automatic assessment of VLE scans.

Prospective multicenter study to evaluate capsule endoscopy competency using a validated assessment tool

BACKGROUND AND AIMS

Capsule endoscopy (CE) is an established, noninvasive modality for examining the small bowel. Minimum training requirements are based primarily on guidelines and expert opinion. A validated tool to assess the competence of CE is lacking. In this prospective, multicenter study, we determined the minimum number of CE procedures required to achieve competence during gastroenterology fellowship; validated a capsule competency test (CapCT); and evaluated any correlation between CE competence and endoscopy experience.

METHODS

We included second- and third-year gastroenterology fellows from 3 institutions between 2013 and 2018 in a structured CE training program with supervised CE interpretation. Fellows completed the CapCT with a maximal score of 100. For comparison, expert faculty completed the same CapCT. Trainee competence was defined as a score ≥90% compared with the mean expert score. Fellows were tested after 15, 25, and 35 supervised CE interpretations. CapCT was validated using expert consensus and item analysis. Data were collected on the number of previous endoscopies.

RESULTS

A total of 68 trainees completed 102 CapCTs. Fourteen CE experts completed the CapCT with a mean score of 94. Mean scores for fellows after 15, 25, and 35 cases were 83, 86, and 87, respectively. Fellows with at least 25 interpretations achieved a mean score ≥84 in all 3 institutions. CapCT item analysis showed high interobserver agreement among expert faculty (k = 0.85). There was no correlation between the scores and the number of endoscopies performed.

CONCLUSION

After a structured CE training program, gastroenterology fellows should complete a minimum of 25 supervised CE interpretations before assessing competence using the validated CapCT, regardless of endoscopy experience.

Interpretation of volumetric laser endomicroscopy in Barrett's esophagus using image enhancement software

Image interpretation of Barrett's esophagus (BE) with volumetric laser endomicroscopy (VLE) can be enhanced by image processing software that highlights established features using a color-graded scale (intelligent real-time image segmentation, IRIS). This study aims to provide a description of IRIS features of various gastroesophageal tissue types using histologic correlation. A database of 80 VLE laser-marked targets with histologic correlation was reviewed for various tissue types. IRIS was applied off-line to the VLE scans, laser-marked targets were identified, and feature review was performed. Squamous epithelium targets (N = 7) showed IRIS layered architecture with lack of surface hyper-reflectivity and epithelial glands. Gastric cardia targets (N = 10) showed absent layering (100%) and surface hyper-reflectivity with epithelial glands (40%). Nondysplastic BE targets (N = 39) showed surface hyper-reflectivity (64%), epithelial glands (51%), and lack of layering (74%). Targets of BE with early neoplasia (N = 24), showed surface hyper-reflectivity (96%), epithelial glands (67%), and lack of layering (96%). IRIS features that characterize each tissue type appear to mirror the nonenhanced VLE counterparts that define them.

Verteporfin- and sodium porfimer-mediated photodynamic therapy enhances pancreatic cancer cell death without activating stromal cells in the microenvironment

The goal of our study was to determine the susceptibility of different pancreatic cell lines to clinically applicable photodynamic therapy (PDT). The efficacy of PDT of two different commercially available photosensitizers, verteporfin and sodium porfimer, was compared using a panel of four different pancreatic cancer cell lines, PANC-1, BxPC-3, CAPAN-2, and MIA PaCa-2, and an immortalized non-neoplastic pancreatic ductal epithelium cell line, HPNE. The minimum effective concentrations and dose-dependent curves of verteporfin and sodium porfimer on PANC-1 were determined. Since pancreatic cancer is known to have significant stromal components, the effect of PDT on stromal cells was also assessed. To mimic tumor-stroma interaction, a co-culture of primary human fibroblasts or human pancreatic stellate cell (HPSCs) line with PANC-1 was used to test verteporfin-PDT-mediated cell death of PANC-1. Two cytokines (TNF-α and IL-1β) were used for stimulation of primary fibroblasts (derived from human esophageal biopsies) or HPSCs. The increased expression of smooth muscle actin (α-SMA) confirmed the activation of fibroblasts or HPSC upon treatment with TNF-α and IL-1β. Cell death assays showed that both sodium porfimer- and verteporfin-mediated PDT-induced cell death in a dose-dependent manner. However, verteporfin-PDT treatment had a greater efficiency with 60  ×   lower concentration than sodium porfimer-PDT in the PANC-1 incubated with stimulated fibroblasts or HPSC. Moreover, activation of stromal cells did not affect the treatment of the pancreatic cancer cell lines, suggesting that the effects of PDT are independent of the inflammatory microenvironment found in this two-dimensional culture model of cancers.

Volumetric laser endomicroscopy features of dysplasia at the gastric cardia in Barrett's oesophagus: results from an observational cohort study

Objective

Volumetric laser endomicroscopy (VLE) is an advanced imaging modality used in Barrett’s oesophagus (BE) to help identify dysplasia in the oesophagus. VLE criteria exist for oesophageal dysplasia but not for dysplasia in the gastric cardia. The aim of this study was to determine if there are in vivo VLE features that can predict gastric cardia dysplasia in BE.

Design

This was a single-centre observational cohort study from August 2016 to August 2018. Patients were included if they had BE, were undergoing a VLE exam as standard of care, and had a suspicious target laser marked at the gastric cardia. The following VLE features were correlated to histology to determine if an association existed between histology subtype and VLE feature: wide crypts, irregular surface, one large isolated gland, multiple glands, and complex glands.

Results

A total of 110 in vivo gastric cardia targets in 77 patients with BE were analysed. The following abnormalities were identified: 61 wide crypts, 34 isolated glands, 16 irregular surfaces, 15 multiple glands, and 11 complex glands. Complex glands were the only VLE feature that correlated to any histology subtype. They were present in 71% of targets with high-grade dysplasia (HGD), T1a cancer or T1b cancer and had a sensitivity, specificity, and accuracy of 71%, 99%, and 85%, respectively. Of the 10 patients with complex glands on VLE and HGD/cancer on histology, 4 had a normal-appearing mucosa (40%) on endoscopy.

Conclusion

Identification of complex glands on VLE may aid in detection of HGD or early cancer in the gastric cardia in BE. This is particularly important, as dysplasia at the gastric cardia can be difficult to see endoscopically.

Timeline and location of recurrence following successful ablation in Barrett's oesophagus: an international multicentre study

OBJECTIVE

Surveillance interval protocols after complete remission of intestinal metaplasia (CRIM) post radiofrequency ablation (RFA) in Barrett's oesophagus (BE) are currently empiric and not based on substantial evidence. We aimed to assess the timeline, location and patterns of recurrence following CRIM to inform these guidelines.

DESIGN

Data on patients undergoing RFA for BE were obtained from prospectively maintained databases of five (three USA and two UK) tertiary referral centres. RFA was performed until CRIM was confirmed on two consecutive endoscopies.

RESULTS

594 patients achieved CRIM as of 1 May 2017. 151 subjects developed recurrent BE over a median (IQR) follow-up of 2.8 (1.4-4.4) years. There was 19% cumulative recurrence risk of any BE within 2 years and an additional 49% risk over the next 8.6 years. There was no evidence of a clinically meaningful change in the recurrence hazard rate of any BE, dysplastic BE or high-grade dysplasia/cancer over the duration of follow-up, with an estimated 2% (95% CI -7% to 12%) change in recurrence rate of any BE in a doubling of follow-up time. 74% of BE recurrences developed at the gastro-oesophageal junction (GOJ) (24.1% were dysplastic) and 26% in the tubular oesophagus. The yield of random biopsies from the tubular oesophagus, in the absence of visible lesions, was 1% (BE) and 0.2% (dysplasia).

CONCLUSIONS

BE recurrence risk following CRIM remained constant over time, suggesting that lengthening of follow-up intervals, at least in the first 5 years after CRIM, may not be advisable. Sampling the GOJ is critical to detecting recurrence. The requirement for random biopsies of the neosquamous epithelium in the absence of visible lesions may need to be re-evaluated.

Esophageal Stricture Following Radiation, Concurrent Immunochemotherapy, Treated With Hyperbaric Oxygen and Dilation

Low-dose palliative radiation may offer symptomatic relief in patients with spinal metastases from primary renal cell cancer and is unlikely to result in radiation injury. Patients with advanced malignancy requiring palliative radiation are often also receiving chemotherapy. Synergistic adverse effects resulting from combined palliative radiation and novel antiprogrammed cell death-1 (anti-PD 1) and/or multityrosine kinase inhibitors are rare.

We report about a 60-year-old woman with metastatic clear-cell renal cancer, status post-left nephrectomy, with debilitating mid-back pain from metastatic tumor burden and foraminal nerve compression. Her chemotherapeutic regimen was repeatedly altered because of progression of disease until she was maintained on the anti-PD 1 checkpoint inhibitor, nivolumab. She received palliative radiation to her thoracic spine over a 2-week period, and nivolumab was then switched to cabozantinib midway through a course of palliative radiation. The patient rapidly developed severe esophagitis, progressing to esophageal stricture, and required placement of a percutaneous endoscopic gastrostomy tube. She was successfully treated with serial esophageal dilation and hyperbaric oxygen treatments to diminish inflammation and improve tissue vascularity. Concurrent use of anti-PD 1 and/or multityrosine kinase drugs may accelerate development of radiation injury regardless of radiation dosage. Radiation-induced esophageal stricture was managed successfully in this patient with serial esophageal dilation and adjuvant hyperbaric oxygen.

Patient-oriented education and visual-aid intervention are inadequate to identify patients with potential capsule retention: a prospective randomized study

Background/aims: The key procedure-related risk with video capsule endoscopy (VCE) is capsule retention, which should be suspected in patients who have not reported capsule passage. The study aims were to determine the frequency of capsule passage visualization and the difference in self-reporting of capsule passage between patients who receive patient-oriented education (POE) and patients who receive POE and a visual aid intervention in the form of a wrist band (WB). Methods: This was a prospective randomized study that enrolled patients undergoing VCE. Patients were randomly assigned to a POE group versus a POE and WB group. POE consisted of verbal education and an information booklet. Both groups received instructions to notify the study team regarding capsule passage. Results: Sixty patients (mean age 57 ± 18 years; 61% female) were included. A total of 57 patients were included in the analysis (3 lost to follow-up; 28 in POE group; 29 in WB group). Capsule passage status was reported by 68% without significant difference between POE and WB groups (72% vs. 64%; p = .51). Capsule passage status was obtained from all 57 patients with the addition of a proactive follow-up. Only 56% (n = 32) reported visualizing capsule passage. Of the remaining patients who did not visualize capsule passage, 60% (n = 15) reported on this without significant difference between the POE and WB groups (p = .23). Conclusions: Lack of visualization of capsule passage is a poor indicator of retention. Self-reporting of VCE passage status is suboptimal and the addition of a visual aid did not improve this parameter.

Outcome of endoscopic mucosal resection in Barrett's esophagus determined by systematic quantification of epithelial glands using volumetric laser endomicroscopy

BACKGROUND

Dysplastic Barrett's esophagus (BE) lesions ≤2 cm in size can be targeted for en-bloc endoscopic mucosal resection (EMR). White-light endoscopy can underestimate the size of a lesion, limiting complete resection. Volumetric laser endomicroscopy (VLE) provides high-resolution cross-sectional imaging of BE. Epithelial glands are a VLE feature associated with BE dysplasia. We study the association between VLE gland quantification and outcome of resection.

METHODS

EMR specimens of BE lesions targeted for en-bloc resection were imaged with VLE using an established protocol. Manual and automated quantification of epithelial glands was performed blinded to resection outcome. The presence of epithelial glands at the resection margins was recorded. Histologic en-bloc (R0) resection of the targeted lesion was defined by the absence and incomplete (R1) resection by the presence of dysplasia/neoplasia at specimen margins.

RESULTS

Thirty-seven EMRs with a mean (standard deviation) size of 1.04 (0.37) cm were imaged with VLE. The highest grade of dysplasia found was low-grade dysplasia (n = 12), high-grade dysplasia (n = 19), and intramucosal cancer (n = 6). The en-bloc resection rate was 37.8% (R0, n = 14; R1, n = 23). The mean (standard deviation) number of epithelial glands quantified with VLE was 13.0 (6.7) and 28.8 (23.9) for R0 and R1 specimens, respectively, with a significant mean difference of 15.8 glands (95% confidence interval, 2-29; P = .02). The presence of glands at the specimen margin was associated with incomplete resection (P < .001).

CONCLUSION

Systematic quantification of BE epithelial glands using VLE can determine the outcome of endoscopic resection. VLE may have a potential role in assessment of lesion margins.

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.

Upper Gastrointestinal Bleeding: Etiologies and Management

Upper gastrointestinal bleeding is a medical condition routinely encountered in clinical practice. Overt upper gastrointestinal bleeding usually presents as melena or hematemesis but can also present as hematochezia in cases of brisk bleeding. The initial evaluation of a patient with suspected upper gastrointestinal bleeding begins with assessment of hemodynamic status, identification of potential risk factors, and appropriate triage of level of care. After resuscitation measures, endoscopic evaluation can be performed to diagnose and potentially treat the source of bleeding. Risk factors that increase the propensity for recurrent bleeding should be identified and addressed.

The evolution of treatment and complications of esophageal food impaction

Background

Esophageal food impaction is relatively common and increasing over time. Treatment ranges from medications to invasive endoscopic therapies. The endoscopic push technique has been advised against in favor of endoscopic retrieval for safety concerns. We sought to assess use patterns and safety of treatments for food impaction in a population-based retrospective review.

Methods

A database of recorded esophageal food impactions in Olmsted County, MN, USA, from 1975-2011 was reviewed for patient demographics, treatment, and complications.

Results

A total of 645 impactions occurred, with increasing incidence over time, peaking at 23.2 per year (2000-2004). Medications (almost exclusively glucagon) were successful in relieving impactions 34.5% of the time when trialed. Urgent endoscopy was common (74.0%), as was the need for endoscopic therapy (67.1%). Endoscopic therapy increased over time, with the endoscopic push technique becoming most common. Esophageal complications (deep mucosal injury or perforation) increased over time but remained rare (peak 11%). There was no difference in complications between push and retrieval techniques.

Conclusions

The endoscopic push technique is safe in comparison to endoscopic retrieval in esophageal food impactions. While complications surrounding impaction have increased, they remain rare. Medication trials are reasonable, as long as they do not delay endoscopy, and may prevent the need for emergent endoscopy in one-third of cases.