Jonathan Hoare

Intracellular localization of the hepatitis B virus HBx protein

The hepatitis B virus (HBV) X protein (HBx) was originally suggested to be a viral transcriptional activator, but its functional mechanisms are still unclear. In this study we have analysed the intracellular localization of HBx in transfected cells and demonstrate that its compartmentalization is dependent on overall expression levels. HBx was exclusively or predominantly localized in the nuclei in weakly expressing cells. However, elevated cellular levels correlated with its accumulation in the cytoplasm, suggesting that the capacity of HBx for nuclear compartmentalization might be limited. Cytoplasmic HBx was detected either as punctate granular staining or in dispersed, finely granular patterns. We have further analysed the detailed cytoplasmic compartmentalization, using confocal microscopy, and show no association with the endoplasmic reticulum, plasma membrane or lysosomes, but a substantial association of HBx with mitochondria. However, a major fraction of cytoplasmic HBx did not localize in mitochondria, indicating the presence of two distinctly compartmentalized cytoplasmic populations. Furthermore, high levels of HBx expression led to an abnormal mitochondrial distribution, involving clumping and organelle aggregation, which was not observed at lower expression levels. The data presented here provide novel insights into the compartmentalization of HBx and may prove important for future evaluations of its functions, both in the viral life-cycle and in the pathology of HBV-related liver disease.

Complement inhibition rescued mice allowing observation of transgene expression following intraportal delivery of baculovirus in mice

The baculovirus Autographa californica nucleo‐polyhedrosis virus (AcNPV) is an alternative to other viral vectors for hepatic gene delivery. A barrier to AcNPV being used in vivo is its susceptibility to inactivation by serum complement 1 . In vivo utility has only been demonstrated using methods that avoid contact with serum 2–5 . We have studied the complement pathways involved in baculovirus inactivation in vitro and the systemic administration of baculovirus vectors in vivo, with the co‐administration of the complement inhibitor, soluble complement inhibitor 1 (sCR1).

Mass Spectrometric Analysis of Exhaled Breath for the Identification of Volatile Organic Compound Biomarkers in Esophageal and Gastric Adenocarcinoma

Objective: The present study assessed whether exhaled breath analysis using Selected Ion Flow Tube Mass Spectrometry could distinguish esophageal and gastric adenocarcinoma from noncancer controls. Background: The majority of patients with upper gastrointestinal cancer present with advanced disease, resulting in poor long-term survival rates. Novel methods are needed to diagnose potentially curable upper gastrointestinal malignancies. Methods: A Profile-3 Selected Ion Flow Tube Mass Spectrometry instrument was used for analysis of volatile organic compounds (VOCs) within exhaled breath samples. All study participants had undergone upper gastrointestinal endoscopy on the day of breath sampling. Receiver operating characteristic analysis and a diagnostic risk prediction model were used to assess the discriminatory accuracy of the identified VOCs. Results: Exhaled breath samples were analyzed from 81 patients with esophageal (N = 48) or gastric adenocarcinoma (N = 33) and 129 controls including Barretts metaplasia (N = 16), benign upper gastrointestinal diseases (N = 62), or a normal upper gastrointestinal tract (N = 51). Twelve VOCs—pentanoic acid, hexanoic acid, phenol, methyl phenol, ethyl phenol, butanal, pentanal, hexanal, heptanal, octanal, nonanal, and decanal—were present at significantly higher concentrations (P < 0.05) in the cancer groups than in the noncancer controls. The area under the ROC curve using these significant VOCs to discriminate esophageal and gastric adenocarcinoma from those with normal upper gastrointestinal tracts was 0.97 and 0.98, respectively. The area under the ROC curve for the model and validation subsets of the diagnostic prediction model was 0.92 ± 0.01 and 0.87 ± 0.03, respectively. Conclusions: Distinct exhaled breath VOC profiles can distinguish patients with esophageal and gastric adenocarcinoma from noncancer controls.

Gastric Cancers Missed During Endoscopy in England.

BACKGROUND & AIMS Single-center studies have estimated that 4.6% to 25.8% of gastric cancers are missed at endoscopy. We performed a population-based study to make a more precise estimate of factors associated with missed lesions in England. METHODS We performed a retrospective population-based observational cohort study of 2727 patients diagnosed with gastric cancer from April 2011 through March 2012 in England, using linked records from 3 national data sets. The primary outcome was the proportion of patients who had undergone endoscopy in the 3 to 36 months before a diagnosis of gastric cancer. We determined this proportion for the entire cohort and for subgroups. RESULTS Of the 2727 patients in the cohort, 8.3% (95% confidence interval, 7.2%-9.3%) underwent endoscopic evaluation in the 3 to 36 months before their diagnosis of gastric cancer. An endoscopy within 3 to 36 months of diagnosis was associated with a diagnosis of early stage cancer (stages 0 or 1, 11.5%; stage 2, 7.9%; stages 3 or 4, 6.9%; P = .01 for stage 0 or 1 vs stage 2 or greater), younger age at diagnosis (<55 y, 13.3% vs ≥55 y, 7.8%; P = .03), and female sex (10% of women vs 7.3% of men; P = .01). Gastric ulcers were detected in 15% of endoscopies performed at any time in the 3 years before cancer diagnosis, and in 64% of endoscopies performed 3 to 6 months before a diagnosis of gastric cancer. CONCLUSIONS Based on a retrospective analysis of medical records in England, in 8.3% of patients with gastric cancer, their cancer was missed at endoscopy within the 3 previous years. A previous endoscopy detected benign gastric ulcers more frequently than any other lesion in patients who later were diagnosed with gastric cancer.

A population-based, retrospective, cohort study of esophageal cancer missed at endoscopy

BACKGROUND AND STUDY AIMS Several studies have suggested that a significant minority of esophageal cancers are missed at endoscopy The aim of this study was to estimate the proportion of esophageal cancers missed at endoscopy on a national level, and to investigate the relationship between miss rates and patient and tumor characteristics. PATIENTS AND METHODS This retrospective, population-based, cohort study identified patients diagnosed with esophageal cancer between April 2011 and March 2012 in England, using two linked databases (National Oesophago-Gastric Cancer Audit and Hospital Episode Statistics). The main outcome was the rate of previous endoscopy within 3 - 36 months of cancer diagnosis. This was calculated for the overall cohort and by patient characteristics, including tumor site and disease stage. RESULTS A total of 6943 new cases of esophageal cancer were identified, of which 7.8 % (95 % confidence interval 7.1 - 8.4) had undergone endoscopy in the 3 - 36 months preceding diagnosis. Of patients with stage 0/1 cancers, 34.0 % had undergone endoscopy in the 3 - 36 months before diagnosis compared with 10.0 % of stage 2 cancers and 4.5 % of stage 3/4 cancers. Of patients with stage 0/1 cancers, 22.1 % were diagnosed after ≥ 3 endoscopies in the previous 3 years. Patients diagnosed with an upper esophageal lesion were more likely to have had an endoscopy in the previous 3 - 12 months (P = 0.040). The most common diagnosis at previous endoscopy was an esophageal ulcer (48.2 % of investigations). CONCLUSION Esophageal cancer may be missed at endoscopy in up to 7.8 % of patients who are subsequently diagnosed with cancer. Endoscopists should make a detailed examination of the whole esophageal mucosa to avoid missing subtle early cancers and lesions in the proximal esophagus. Patients with an esophageal cancer may be misdiagnosed as having a benign esophageal ulcer.

Images of the terminal ileum are more convincing than cecal images for verifying the extent of colonoscopy

BACKGROUND AND STUDY AIMS Independent verification of colonoscopy completion is important for quality assurance. Cecal photographs aimed at showing key landmarks, including the ileocecal valve (ICV) and appendiceal orifice are the currently recommended standard, but are often perceived as unreliable. Images of the terminal ileum demonstrating villi may provide more robust evidence of completion. We sought to prospectively evaluate the ease of routine intubation of the terminal ileum and to compare the effectiveness of terminal ileum and cecal photographs in convincing independent reviewers that total colonoscopy had been accomplished. PATIENTS AND METHODS A prospective, observational study evaluated 216 consecutively completed colonoscopies performed in routine clinical practice. Cecal and terminal ileum photographs were evaluated and scored by independent reviewers. Frequency of terminal ileum intubation, time required, and safety parameters were recorded. RESULTS The terminal ileum was intubated and photographed in 188/216 (87%) of cases. Median time taken to intubate, or attempt to intubate the terminal ileum was 1 min 24 s, and was achieved without complications or requirement for additional sedation. Terminal ileum images were significantly more likely to be considered convincing than cecal images ( P<0.0001 for all reviewers). There was excellent interobserver agreement amongst the opinion of reviewers regarding terminal ileum photographs (kappa=0.91). CONCLUSION Terminal ileum intubation is achievable rapidly and safely in the majority of patients undergoing colonoscopy. Terminal ileum images provide more convincing evidence of complete examination of the colon than cecal images, even when attempts to capture images specifically of the ICV and appendiceal orifice are made.

Looking towards objective quality evaluation in colonoscopy: Analysis of visual gaze patterns

There are currently limited training and assessment tools available to novice endoscopists. A potential tool for the objective assessment of endoscopist visual search strategy is eye‐tracking technology. The aim of this study is to assess whether eye‐tracking technology can be used to differentiate the visual gaze patterns (VGP) of experienced and novice endoscopists, and to characterize any differences arising between the two groups.

53 Six Year Disease Durability Outcomes on Patients Treated With Endoscopic Therapy for Barrett's Related Neoplasia From the UK Registry

Introduction Endoscopic therapy with combined Endoscopic mucosal resection (EMR) followed by Radiofrequency ablation (RFA) is now the recommended first line treatment for patients with Barrett’s (BE) related neoplasia confined to the oesophageal mucosa. Method We examine prospective data from the United Kingdom registry of patients undergoing RFA/EMR for BE neoplasia since 2008. Before RFA, visible lesions and nodularity were entirely removed by EMR. Thereafter patients underwent RFA 3 monthly until all visible BE was ablated or cancer developed (endpoints). Biopsies were taken at 12 months or when endpoints reached. Follow up endoscopies were performed periodically in all patients to check for recurrences thereafter. All patients who had completed at least 12 months of follow up after successful treatment were included in the analysis to examine durability of disease reversal long term. Results 282 patients (81% male, mean age 70 years) have completed the 12 month treatment protocol with a minimum of 12 months follow up thereafter. At median follow up of 37 months (IQR 29–49), 93% of patients with successful disease reversal were still free of neoplasia and 88% free of intestinal metaplasia recurrence. Cancer progression at this same time was seen in 1.4% of patients. Kaplan Meier (KM) statistics demonstrated a predicted 3 year neoplasia free survival in 88% of patients. At 5 and 6 years this was 86%. Similarly KM analysis showed that at 3 years 81% of patients would be free form BE and at 5 and 6 years this figure was 73%. Conclusion We report long term outcomes of a large cohort of patients with BE neoplasia who have had successful endoscopic therapy with RFA/EMR. This approach appears to have a lasting disease free benefit in the majority of patients. Recurrences do occur in a minority of patients and highlights the need for follow up in those fit for endoscopy. All collaborators of the UK RFA registry are acknowledged for their contributions to data collection for this work. Disclosure of interest None Declared.

Gastrointestinal Images: Complete Tubular Duplication of the Oesophagus in an Adult

IntroductionDuplication of the oesophagus is a rare congenital abnormality that usually presents in children. Presentation in adults is extremely rare.Case HistoryWe report a case of a19-year-old gentleman presenting with general gastrointestinal symptoms of pain and dysphagia. Diagnosis was made with CT and contrast studies, demonstrating complete tubular duplication of the oesophagus with communications at both ends of the duplication. The patient was managed conservatively.DiscussionWe describe the difficulty in diagnosing these rare congenital abnormalities. We recommend that with a multi-disciplinary approach, conservative management can be considered.

Population-based cohort study of the management and survival of patients with early-stage oesophageal adenocarcinoma in England

Until recently, oesophagectomy was the treatment of choice for early oesophageal cancer. Endoscopic treatment has been introduced relatively recently. This observational national database study aimed to describe how endoscopic therapy has been introduced in England and to examine the safety of this approach.