Diagnostic yield from symptomatic gastroscopy in the UK: British Society of Gastroenterology analysis using data from the National Endoscopy Database

OBJECTIVE

This national analysis aimed to calculate the diagnostic yield from gastroscopy for common symptoms, guiding improved resource utilisation.

DESIGN

A cross-sectional study was conducted of diagnostic gastroscopies between 1 March 2019 and 29 February 2020 using the UK National Endoscopy Database. Mixed-effect logistic regression models were used, incorporating random (endoscopist) and fixed (symptoms, age and sex) effects on two dependent variables (endoscopic cancer; Barrett's oesophagus (BO) diagnosis). Adjusted positive predictive values (aPPVs) were calculated.

RESULTS

382 370 diagnostic gastroscopies were analysed; 30.4% were performed in patients aged <50 and 57.7% on female patients. The overall unadjusted PPV for cancer was 1.0% (males 1.7%; females 0.6%, p<0.01). Other major pathology was found in 9.1% of procedures, whereas 89.9% reported only normal findings or minor pathology (92.5% in females; 94.6% in patients <50).Highest cancer aPPVs were reached in the over 50s (1.3%), in those with dysphagia (3.0%) or weight loss plus another symptom (1.4%). Cancer aPPVs for all other symptoms were below 1%, and for those under 50, remained below 1% regardless of symptom. Overall, 73.7% of gastroscopies were carried out in patient groups where aPPV cancer was <1%.The overall unadjusted PPV for BO was 4.1% (males 6.1%; females 2.7%, p<0.01). The aPPV for BO for reflux was 5.8% and ranged from 3.2% to 4.0% for other symptoms.

CONCLUSIONS

Cancer yield was highest in elderly male patients, and those over 50 with dysphagia. Three-quarters of all gastroscopies were performed on patients whose cancer risk was <1%, suggesting inefficient resource utilisation.

Understanding the malignant potential of gastric metaplasia of the oesophagus and its relevance to Barrett's oesophagus surveillance: individual-level data analysis

OBJECTIVE

Whether gastric metaplasia (GM) of the oesophagus should be considered as Barrett's oesophagus (BO) is controversial. Given concern intestinal metaplasia (IM) may be missed due to sampling, the UK guidelines include GM as a type of BO. Here, we investigated whether the risk of misdiagnosis and the malignant potential of GM warrant its place in the UK surveillance.

DESIGN

We performed a thorough pathology and endoscopy review to follow clinical outcomes in a novel UK cohort of 244 patients, covering 1854 person years of follow-up. We complemented this with a comparative genomic analysis of 160 GM and IM specimens, focused on early molecular hallmarks of BO and oesophageal adenocarcinoma (OAC).

RESULTS

We found that 58 of 77 short-segment (<3 cm) GM (SS-GM) cases (75%) continued to be observed as GM-only across a median of 4.4 years of follow-up. We observed that disease progression in GM-only cases and GM+IM cases (cases with reported GM on some occasions, IM on others) was significantly lower than in the IM-only cases (Kaplan-Meier, p=0.03). Genomic analysis revealed that the mutation burden in GM is significantly lower than in IM (p<0.01). Moreover, GM does not bear the mutational hallmarks of OAC, with an absence of associated signatures and driver gene mutations. Finally, we established that GM found adjacent to OAC is evolutionarily distant from cancer.

CONCLUSION

SS-GM is a distinct entity from SS-IM and the malignant potential of GM is lower than IM. It is questionable whether SS-GM warrants inclusion in BO surveillance.

Long-term risk factors for developing Barrett's oesophagus in patients with gastro-oesophageal reflux disease: a longitudinal cohort study

BACKGROUND AND AIMS

Several characteristics are known to affect the risk of Barrett's oesophagus (BO) in the general population, with symptomatic gastro-oesophageal reflux disease (GORD) being a critical risk factor. In this study, we examined factors that influence BO development in people living with GORD.

DESIGN

People living with GORD were recruited from an endoscopy unit with lifestyle, medical and prescribing history collected. Logistic regression analysis was undertaken to assess the effects of multiple parameters on the likelihood of developing BO.

RESULTS

1197 participants were recruited. Most were Caucasian (n=1188, 99%), had no formal educational qualifications (n=714; 59.6%) and lived with overweight (mean body mass index >25 kg/m2). Many lived in areas of least socioeconomic resource (n=568; 47.4%). 139 (11.6%) had BO at baseline. In adjusted baseline analysis (n=1197), male sex (adjusted OR, aOR 2.04 (95% CI 1.92 to 4.12), p≤0.001), increasing age (aOR 1.03 (95% CI 1.01 to 1.04), p≤0.0001) and proton pump inhibitor use (aOR 3.03 (95% CI 1.80 to 5.13), p≤0.0001) were associated with higher odds of BO. At follow-up (n=363), 22 (6.1%) participants developed BO; male sex (aOR 3.18 (95% CI 1.28 to 7.86), p=0.012), pack-years cigarettes smoked (aOR 1.04 (95% CI 1.00 to 1.08), p=0.046) and increased alcohol intake (aOR 1.02 (95% CI 1.00 to 1.04), p=0.013), were associated with increased odds of BO.

CONCLUSION

Male sex, pack-years cigarettes smoked, and increasing alcohol intake, were independently associated with increased odds of developing BO over 20-year follow-up. These results align with research linking male sex and smoking with BO and extend this by implicating the potential role of alcohol in developing BO, which may require communication through public health messaging.

Dedicated service for Barrett's oesophagus surveillance endoscopy yields higher dysplasia detection and guideline adherence in a non-tertiary setting in the UK: a 5-year comparative cohort study

Objective

Barrett's oesophagus (BO) endoscopic surveillance is performed to varying quality, dedicated services may offer improved outcomes. This study compares a dedicated BO service to standard care, specifically dysplasia detection rate (DDR), guideline adherence and use of advanced imaging modalities in a non-tertiary setting.

Design/method

5-year retrospective comparative cohort study comparing a dedicated BO endoscopy service with surveillance performed on non-dedicated slots at a non-tertiary centre in the UK. All adult patients undergoing BO surveillance between 1 March 2016 and 1 March 2021 were reviewed and those who underwent endoscopy on a dedicated BO service run by endoscopists with training in BO was compared with patients receiving their BO surveillance on any other endoscopy list. Endoscopy reports, histology results and clinic letters were reviewed for DDR and British society of gastroenterology guideline adherence.

Results

921 BO procedures were included (678 patients). 574 (62%) endoscopies were on a dedicated BO list vs 348 (38%) on non-dedicated.DDR was significantly higher in the dedicated cohort 6.3% (36/568) vs 2.7% (9/337) (p=0.014). Significance was sustained when cases with indefinite for dysplasia were excluded: 4.9% 27/533 vs 0.9% 3/329 (p=0.002). Guideline adherence was significantly better on the dedicated endoscopy lists.Factors associated with dysplasia detection in regression analysis included visible lesion documentation (p=0.036), use of targeted biopsies (p=<0.001), number of biopsies obtained (p≤0.001).

Conclusions

A dedicated Barrett's service showed higher DDR and guideline adherence than standard care and may be beneficial pending randomised trial data.

Quality of life measures in dysplastic Barrett's oesophagus are comparable to patients with non-dysplastic Barrett's oesophagus and do not improve after endoscopic therapy

OBJECTIVE

Barrett's oesophagus (BO) is a precursor lesion, via dysplastic phases, to oesophageal adenocarcinoma. Although overall risk from BO is low, it has been shown to adversely affect health-related quality of life (HRQOL). The aim was to compare dysplastic BO patients' HRQOL pre-endoscopic therapy (pre-ET) and post-ET. The pre-ET BO group was also compared with other cohorts: non-dysplastic BO (NDBO), those with colonic polyps, gastro-oesophageal reflux disease (GORD) and healthy volunteers.

DESIGN

Participants in the pre-ET cohort were recruited prior to their endotherapy and HRQOL questionnaires provided pre-ET and post-ET. Wilcoxon rank test was used to compare the pre-ET and post-ET findings. The Pre-ET group was compared to the other cohorts' HRQOL results using multiple linear regression analysis.

RESULTS

Pre-ET group of 69 participants returned the questionnaires prior to and 42 post-ET. Both the pre-ET and post-ET group showed similar levels of cancer worry, despite the treatment. No statistical significance was found for symptoms scores, anxiety and depression or general health measures with the Short Form-36 (SF-36) Score. Education for the BO patients was overall lacking with many of the pre-ET group still reporting unanswered questions about their disease.The Pre-ET group was compared with NDBO group (N=379), GORD (N=132), colonic polyp patients (N=152) and healthy volunteers (N=48). Cancer worry was similar between the NDBO group and the Pre-ET group, despite their lower risk of progression. GORD patients had worse symptom scores from a reflux and heartburn perspective. Only the healthy group has significantly better scores in the SF-36 and improved hospital anxiety and depression scores.

CONCLUSION

These findings suggest that there is a need to improve HRQOL for patients with BO. This should include improved education and devising-specific patient-reported outcome measures for BO to capture relevant areas of HRQOL in future studies.

GWAS meta-analysis of 16 790 patients with Barrett's oesophagus and oesophageal adenocarcinoma identifies 16 novel genetic risk loci and provides insights into disease aetiology beyond the single marker level

OBJECTIVE

Oesophageal cancer (EC) is the sixth leading cause of cancer-related deaths. Oesophageal adenocarcinoma (EA), with Barrett's oesophagus (BE) as a precursor lesion, is the most prevalent EC subtype in the Western world. This study aims to contribute to better understand the genetic causes of BE/EA by leveraging genome wide association studies (GWAS), genetic correlation analyses and polygenic risk modelling.

DESIGN

We combined data from previous GWAS with new cohorts, increasing the sample size to 16 790 BE/EA cases and 32 476 controls. We also carried out a transcriptome wide association study (TWAS) using expression data from disease-relevant tissues to identify BE/EA candidate genes. To investigate the relationship with reported BE/EA risk factors, a linkage disequilibrium score regression (LDSR) analysis was performed. BE/EA risk models were developed combining clinical/lifestyle risk factors with polygenic risk scores (PRS) derived from the GWAS meta-analysis.

RESULTS

The GWAS meta-analysis identified 27 BE and/or EA risk loci, 11 of which were novel. The TWAS identified promising BE/EA candidate genes at seven GWAS loci and at five additional risk loci. The LDSR analysis led to the identification of novel genetic correlations and pointed to differences in BE and EA aetiology. Gastro-oesophageal reflux disease appeared to contribute stronger to the metaplastic BE transformation than to EA development. Finally, combining PRS with BE/EA risk factors improved the performance of the risk models.

CONCLUSION

Our findings provide further insights into BE/EA aetiology and its relationship to risk factors. The results lay the foundation for future follow-up studies to identify underlying disease mechanisms and improving risk prediction.

Kyoto international consensus report on anatomy, pathophysiology and clinical significance of the gastro-oesophageal junction

OBJECTIVE

An international meeting was organised to develop consensus on (1) the landmarks to define the gastro-oesophageal junction (GOJ), (2) the occurrence and pathophysiological significance of the cardiac gland, (3) the definition of the gastro-oesophageal junctional zone (GOJZ) and (4) the causes of inflammation, metaplasia and neoplasia occurring in the GOJZ.

DESIGN

Clinical questions relevant to the afore-mentioned major issues were drafted for which expert panels formulated relevant statements and textural explanations.A Delphi method using an anonymous system was employed to develop the consensus, the level of which was predefined as ≥80% of agreement. Two rounds of voting and amendments were completed before the meeting at which clinical questions and consensus were finalised.

RESULTS

Twenty eight clinical questions and statements were finalised after extensive amendments. Critical consensus was achieved: (1) definition for the GOJ, (2) definition of the GOJZ spanning 1 cm proximal and distal to the GOJ as defined by the end of palisade vessels was accepted based on the anatomical distribution of cardiac type gland, (3) chemical and bacterial (Helicobacter pylori) factors as the primary causes of inflammation, metaplasia and neoplasia occurring in the GOJZ, (4) a new definition of Barrett's oesophagus (BO).

CONCLUSIONS

This international consensus on the new definitions of BO, GOJ and the GOJZ will be instrumental in future studies aiming to resolve many issues on this important anatomic area and hopefully will lead to better classification and management of the diseases surrounding the GOJ.

Transnasal endoscopy: moving from endoscopy to the clinical outpatient-blue sky thinking in oesophageal testing

BACKGROUND

COVID-19 has severely affected UK endoscopy services with an estimate 86% loss of activity during the first wave. Subsequent delays in diagnostic and surveillance procedures highlight the need for novel solutions to tackle the resultant backlog. Transnasal endoscopy (TNE) provides an attractive option compared with conventional upper gastrointestinal endoscopy given its limited use of space, no sedation and reduced nursing resources.

OUR EXPERIENCE

We describe piloting and then establishing an outpatient model TNE service in the pandemic era and the implications on resource allocation, training and workforce. We also discuss our experiences and outline ways in which services can evolve to undertake more complex endoscopic diagnostic and therapeutic work. Over 90% of patients describe no discomfort and those who have previously experienced conventional transoral endoscopy preferred the transnasal approach. We describe a low complication rate (0.8%) comprising two episodes of mild epistaxis. The average procedure duration was reasonable (9.9±5.0 min) with full adherence to Joint Advisory Group quality standards. All biopsies assessed were deemed sufficient for diagnosis including those for surveillance procedures.

DISCUSSION

TNE can offer a safe, tolerable, high-quality service outside of a conventional endoscopy setting. Expanding procedural capacity without impacting on the current endoscopy footprint has great potential in recovering endoscopy services following the COVID-19 pandemic. Looking forward, TNE has potential to be used both within the endoscopy suite as part of therapeutic procedures, or outside of the endoscopy unit in outpatient clinics, community hospitals, or mobile units and to achieve this in a more sustainable and environmentally friendly way.

Germline variation in inflammation-related pathways and risk of Barrett's oesophagus and oesophageal adenocarcinoma

OBJECTIVE

Oesophageal adenocarcinoma (OA) incidence has risen sharply in Western countries over recent decades. Local and systemic inflammation is considered an important contributor to OA pathogenesis. Established risk factors for OA and its precursor, Barrett's oesophagus (BE), include symptomatic reflux, obesity and smoking. The role of inherited genetic susceptibility remains an area of active investigation. Here, we explore whether germline variation related to inflammatory processes influences susceptibility to BE/OA.

DESIGN

We used data from a genomewide association study of 2515 OA cases, 3295 BE cases and 3207 controls. Our analysis included 7863 single-nucleotide polymorphisms (SNPs) in 449 genes assigned to five pathways: cyclooxygenase (COX), cytokine signalling, oxidative stress, human leucocyte antigen and nuclear factor-κB. A principal components-based analytic framework was employed to evaluate pathway-level and gene-level associations with disease risk.

RESULTS

We identified a significant signal for the COX pathway in relation to BE risk (p=0.0059, false discovery rate q=0.03), and in gene-level analyses found an association with microsomal glutathione-S-transferase 1 (MGST1); (p=0.0005, q=0.005). Assessment of 36 MGST1 SNPs identified 14 variants associated with elevated BE risk (q<0.05). Four of these were subsequently confirmed (p<5.5×10-5) in a meta-analysis encompassing an independent set of 1851 BE cases and 3496 controls, and are known strong expression quantitative trait loci for MGST1. Three such variants were associated with similar elevations in OA risk.

CONCLUSIONS

This study provides the most comprehensive evaluation of inflammation-related germline variation in relation to risk of BE/OA and suggests that variants in MGST1 influence disease susceptibility.

Endoscopic management of Barrett's and early oesophageal neoplasia

Barrett's oesophagus (BO) is the only known precursor to oesophageal adenocarcinoma (OAC). Dysplasia and intramucosal cancer arising in BO can safely be treated with endoscopic eradication therapy (EET) due to the low risk of subsequent lymph node metastasis. Treatment at an early stage is paramount due to the ongoing poor prognosis and outcomes of patients with advanced OAC. The mainstay of treatment is endoscopic resection of visible lesions for accurate staging followed by ablation therapy to all remaining columnar-lined epithelium, most commonly with radiofrequency ablation. Successful eradication of dysplasia can be achieved in >95% of patients with this EET combined approach.

Monitoring the premalignant potential of Barrett's oesophagus'

The landscape for patients with Barrett's oesophagus (BE) has changed significantly in the last decade. Research and new guidelines have helped gastroenterologists to better identify those patients with BE who are particularly at risk of developing oesophageal adenocarcinoma. In parallel, developments in endoscopic image enhancement technology and optical biopsy techniques have improved our ability to detect high-risk lesions. Once these lesions have been identified, the improvements in minimally invasive endoscopic therapies has meant that these patients can potentially be cured of early cancer and high-risk dysplastic lesions without the need for surgery, which still has a significant morbidity and mortality. The importance of reaching an accurate diagnosis of BE remains of paramount importance. More work is needed, however. The vast majority of those undergoing surveillance for their BE do not progress towards cancer and thus undergo a regular invasive procedure, which may impact on their psychological and physical well-being while incurring significant cost to the health service. New work that explores cheaper endoscopic or non-invasive ways to identify the at-risk individual provides exciting avenues for research. In future, the diagnosis and monitoring of patients with BE could move away from hospitals and into primary care.

Transnasal endoscopy: no gagging no panic!

BACKGROUND

Transnasal endoscopy (TNE) is performed with an ultrathin scope via the nasal passages and is increasingly used. This review covers the technical characteristics, tolerability, safety and acceptability of TNE and also diagnostic accuracy, use as a screening tool and therapeutic applications. It includes practical advice from an ear, nose, throat (ENT) specialist to optimise TNE practice, identify ENT pathology and manage complications.

METHODS

A Medline search was performed using the terms "transnasal", "ultrathin", "small calibre", "endoscopy", "EGD" to identify relevant literature.

RESULTS

There is increasing evidence that TNE is better tolerated than standard endoscopy as measured using visual analogue scales, and the main area of discomfort is nasal during insertion of the TN endoscope, which seems remediable with adequate topical anaesthesia. The diagnostic yield has been found to be similar for detection of Barrett's oesophagus, gastric cancer and GORD-associated diseases. There are some potential issues regarding the accuracy of TNE in detecting small early gastric malignant lesions, especially those in the proximal stomach. TNE is feasible and safe in a primary care population and is ideal for screening for upper gastrointestinal pathology. It has an advantage as a diagnostic tool in the elderly and those with multiple comorbidities due to fewer adverse effects on the cardiovascular system. It has significant advantages for therapeutic procedures, especially negotiating upper oesophageal strictures and insertion of nasoenteric feeding tubes.

CONCLUSIONS

TNE is well tolerated and a valuable diagnostic tool. Further evidence is required to establish its accuracy for the diagnosis of early and small gastric malignancies. There is an emerging role for TNE in therapeutic endoscopy, which needs further study.

Derivation of genetic biomarkers for cancer risk stratification in Barrett's oesophagus: a prospective cohort study

OBJECTIVE

The risk of developing adenocarcinoma in non-dysplastic Barrett's oesophagus is low and difficult to predict. Accurate tools for risk stratification are needed to increase the efficiency of surveillance. We aimed to develop a prediction model for progression using clinical variables and genetic markers.

METHODS

In a prospective cohort of patients with non-dysplastic Barrett's oesophagus, we evaluated six molecular markers: p16, p53, Her-2/neu, 20q, MYC and aneusomy by DNA fluorescence in situ hybridisation on brush cytology specimens. Primary study outcomes were the development of high-grade dysplasia or oesophageal adenocarcinoma. The most predictive clinical variables and markers were determined using Cox proportional-hazards models, receiver operating characteristic curves and a leave-one-out analysis.

RESULTS

A total of 428 patients participated (345 men; median age 60 years) with a cumulative follow-up of 2019 patient-years (median 45 months per patient). Of these patients, 22 progressed; nine developed high-grade dysplasia and 13 oesophageal adenocarcinoma. The clinical variables, age and circumferential Barrett's length, and the markers, p16 loss, MYC gain and aneusomy, were significantly associated with progression on univariate analysis. We defined an 'Abnormal Marker Count' that counted abnormalities in p16, MYC and aneusomy, which significantly improved risk prediction beyond using just age and Barrett's length. In multivariate analysis, these three factors identified a high-risk group with an 8.7-fold (95% CI 2.6 to 29.8) increased HR when compared with the low-risk group, with an area under the curve of 0.76 (95% CI 0.66 to 0.86).

CONCLUSIONS

A prediction model based on age, Barrett's length and the markers p16, MYC and aneusomy determines progression risk in non-dysplastic Barrett's oesophagus.

Asia-Pacific consensus on the management of gastro-oesophageal reflux disease: an update focusing on refractory reflux disease and Barrett's oesophagus

OBJECTIVE

Since the publication of the Asia-Pacific consensus on gastro-oesophageal reflux disease in 2008, there has been further scientific advancement in this field. This updated consensus focuses on proton pump inhibitor-refractory reflux disease and Barrett's oesophagus.

METHODS

A steering committee identified three areas to address: (1) burden of disease and diagnosis of reflux disease; (2) proton pump inhibitor-refractory reflux disease; (3) Barrett's oesophagus. Three working groups formulated draft statements with supporting evidence. Discussions were done via email before a final face-to-face discussion. We used a Delphi consensus process, with a 70% agreement threshold, using Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria to categorise the quality of evidence and strength of recommendations.

RESULTS

A total of 32 statements were proposed and 31 were accepted by consensus. A rise in the prevalence rates of gastro-oesophageal reflux disease in Asia was noted, with the majority being non-erosive reflux disease. Overweight and obesity contributed to the rise. Proton pump inhibitor-refractory reflux disease was recognised to be common. A distinction was made between refractory symptoms and refractory reflux disease, with clarification of the roles of endoscopy and functional testing summarised in two algorithms. The definition of Barrett's oesophagus was revised such that a minimum length of 1 cm was required and the presence of intestinal metaplasia no longer necessary. We recommended the use of standardised endoscopic reporting and advocated endoscopic therapy for confirmed dysplasia and early cancer.

CONCLUSIONS

These guidelines standardise the management of patients with refractory gastro-oesophageal reflux disease and Barrett's oesophagus in the Asia-Pacific region.

The use of optical imaging techniques in the gastrointestinal tract

With significant advances in the management of gastrointestinal disease there has been a move from diagnosing advanced pathology, to detecting early lesions that are potentially amenable to curative endoscopic treatment. This has required an improvement in diagnostics, with a focus on identifying and characterising subtle mucosal changes. There is great interest in the use of optical technologies to predict histology and enable the formulation of a real-time in vivo diagnosis, a so-called 'optical biopsy'. The aim of this review is to explore the evidence for the use of the current commercially available imaging techniques in the gastrointestinal tract.

Evolution of oesophageal adenocarcinoma from metaplastic columnar epithelium without goblet cells in Barrett's oesophagus

OBJECTIVE

Barrett's oesophagus commonly presents as a patchwork of columnar metaplasia with and without goblet cells in the distal oesophagus. The presence of metaplastic columnar epithelium with goblet cells on oesophageal biopsy is a marker of cancer progression risk, but it is unclear whether clonal expansion and progression in Barrett's oesophagus is exclusive to columnar epithelium with goblet cells.

DESIGN

We developed a novel method to trace the clonal ancestry of an oesophageal adenocarcinoma across an entire Barrett's segment. Clonal expansions in Barrett's mucosa were identified using cytochrome c oxidase enzyme histochemistry. Somatic mutations were identified through mitochondrial DNA sequencing and single gland whole exome sequencing.

RESULTS

By tracing the clonal origin of an oesophageal adenocarcinoma across an entire Barrett's segment through a combination of histopathological spatial mapping and clonal ordering, we find that this cancer developed from a premalignant clonal expansion in non-dysplastic ('cardia-type') columnar metaplasia without goblet cells.

CONCLUSION

Our data demonstrate the premalignant potential of metaplastic columnar epithelium without goblet cells in the context of Barrett's oesophagus.

Impact of surveillance for Barrett's oesophagus on tumour stage and survival of patients with neoplastic progression

OBJECTIVE

Endoscopic surveillance for Barrett's oesophagus (BO) is under discussion given the overall low incidence of neoplastic progression and lack of evidence that it prevents advanced oesophageal adenocarcinoma (OAC). The aim of this study was to evaluate the impact of endoscopic BO surveillance on tumour stage and survival of patients with neoplastic progression.

DESIGN

783 patients with BO of at least 2 cm were included in a multicentre prospective cohort and followed during surveillance according to the American College of Gastroenterology guidelines. Cases of high-grade dysplasia and OAC were identified during follow-up. OAC staging was performed according to the 7th UICC-AJCC classification. Survival data were collected and crosschecked using death and municipal registries. Data from patients with OAC in the general population were obtained from the Dutch cancer registry. We compared survival of patients with BO with neoplastic progression during surveillance with those of patients without neoplastic progression and patients with OAC in the general population.

RESULTS

53 patients with BO developed high-grade dysplasia or OAC during surveillance. Thirty-five (66%) were classified as stage 0, 14 (26%) as stage 1 and 4 (8%) as stage 2. OAC was diagnosed at an earlier stage during BO surveillance than in the general population (p<0.001). Survival of patients with BO with neoplastic progression was not significantly worse than those of patients without neoplastic progression and similar to survival of patients with stage 0 or stage 1 OAC in the general population.

CONCLUSIONS

OAC is detected at an earlier stage during BO surveillance than in the general population with good survival rates.

Length of Barrett's oesophagus and cancer risk: implications from a large sample of patients with early oesophageal adenocarcinoma

OBJECTIVE

Although it is well understood that the risk of oesophageal adenocarcinoma increases with Barrett length, transition risks for cancer associated with different Barrett lengths are unknown. We aimed to estimate annual cancer transition rates for patients with long-segment (≥3 cm), short-segment (≥1 to <3 cm) and ultra-short-segment (<1 cm) Barrett's oesophagus.

DESIGN

We used three data sources to estimate the annual cancer transition rates for each Barrett length category: (1) the distribution of long, short and ultra-short Barrett's oesophagus among a large German cohort with newly diagnosed T1 oesophageal adenocarcinoma; (2) population-based German incidence of oesophageal adenocarcinoma; and (3) published estimates of the population prevalence of Barrett's oesophagus for each Barrett length category.

RESULTS

Among 1017 patients with newly diagnosed T1 oesophageal adenocarcinoma, 573 (56%) had long-segment, 240 (24%) short-segment and 204 (20%) ultra-short-segment Barrett's oesophagus. The base-case estimates for the prevalence of Barrett's oesophagus among the general population were 1.5%, 5% and 14%, respectively. The annual cancer transition rates for patients with long, short and ultra-short Barrett's oesophagus were 0.22%, 0.03% and 0.01%, respectively. To detect one cancer, 450 patients with long-segment Barrett's oesophagus would need to undergo annual surveillance endoscopy; in short segment and ultra-short segment, the corresponding numbers of patients would be 3440 and 12,364. Similar results were obtained when applying US incidence data.

CONCLUSIONS

The large number of patients, who need to undergo endoscopic surveillance to detect one cancer, raises questions about the value of surveillance endoscopy in patients with short segment or ultra-short segment of Barrett's oesophagus.

Barrett's oesophagus length is established at the time of initial endoscopy and does not change over time: results from a large multicentre cohort

OBJECTIVE

It is unclear whether Barrett's oesophagus (BO) length changes over time or whether the full length of the segment is established at the onset of disease recognition. The objectives of this study were to evaluate the association of age and BO length and to evaluate the changes in BO length over time.

DESIGN

This is a prospective, multicentre cohort study involving patients with BO from five centres. Patients were divided into groups based on the decade of initial diagnosis of BO. The mean BO length and the mean change in BO length were calculated for each age decade. The mean change in BO length was also calculated between the index endoscopy and the last surveillance endoscopy.

RESULTS

3635 patients with BO were included in the study: 87.8% men, 92.8% Caucasians, mean age 60.9 years and mean BO length 3.5 cm. The mean change in BO length was 0.9 cm. The mean BO length did not significantly change for each age category: <30 years (4.6 cm), 30-39.9 years (3.2 cm), 40-49.9 years (3.1 cm), 50-59.9 years (3.1 cm), 60-69.9 years (3.6 cm), 70-79.7 (4.0 cm) and >80 years (4.5 cm), p=0.47. On subgroup analysis of patients with non-dysplastic BO who had at least 1 year of endoscopic follow up, there was a significant decrease in mean change in BO length across age categories ranging from +1.7 to -0.8 cm, p=0.03.

CONCLUSIONS

There was no significant difference in BO length by age category in decades. In addition, the change in BO length from index to follow-up endoscopy was similar among patients >30 years. These findings suggest that a patient's BO segment length attains its full extent by the time of the initial endoscopic examination.

Emerging optical methods for surveillance of Barrett's oesophagus

The rapid rise in incidence of oesophageal adenocarcinoma has motivated the need for improved methods for surveillance of Barrett's oesophagus. Early neoplasia is flat in morphology and patchy in distribution and is difficult to detect with conventional white light endoscopy (WLE). Light offers numerous advantages for rapidly visualising the oesophagus, and advanced optical methods are being developed for wide-field and cross-sectional imaging to guide tissue biopsy and stage early neoplasia, respectively. We review key features of these promising methods and address their potential to improve detection of Barrett's neoplasia. The clinical performance of key advanced imaging technologies is reviewed, including (1) wide-field methods, such as high-definition WLE, chromoendoscopy, narrow-band imaging, autofluorescence and trimodal imaging and (2) cross-sectional techniques, such as optical coherence tomography, optical frequency domain imaging and confocal laser endomicroscopy. Some of these instruments are being adapted for molecular imaging to detect specific biological targets that are overexpressed in Barrett's neoplasia. Gene expression profiles are being used to identify early targets that appear before morphological changes can be visualised with white light. These targets are detected in vivo using exogenous probes, such as lectins, peptides, antibodies, affibodies and activatable enzymes that are labelled with fluorescence dyes to produce high contrast images. This emerging approach has potential to provide a 'red flag' to identify regions of premalignant mucosa, outline disease margins and guide therapy based on the underlying molecular mechanisms of cancer progression.

Improvement over time in outcomes for patients undergoing endoscopic therapy for Barrett's oesophagus-related neoplasia: 6-year experience from the first 500 patients treated in the UK patient registry

BACKGROUND

Barrett's oesophagus (BE) is a pre-malignant condition leading to oesophageal adenocarcinoma (OAC). Treatment of neoplasia at an early stage is desirable. Combined endoscopic mucosal resection (EMR) followed by radiofrequency ablation (RFA) is an alternative to surgery for patients with BE-related neoplasia.

METHODS

We examined prospective data from the UK registry of patients undergoing RFA/EMR for BE-related neoplasia from 2008 to 2013. Before RFA, visible lesions were removed by EMR. Thereafter, patients had RFA 3-monthly until all BE was ablated or cancer developed (endpoints). End of treatment biopsies were recommended at around 12 months from first RFA treatment or when endpoints were reached. Outcomes for clearance of dysplasia (CR-D) and BE (CR-IM) at end of treatment were assessed over two time periods (2008-2010 and 2011-2013). Durability of successful treatment and progression to OAC were also evaluated.

RESULTS

508 patients have completed treatment. CR-D and CR-IM improved significantly between the former and later time periods, from 77% and 56% to 92% and 83%, respectively (p<0.0001). EMR for visible lesions prior to RFA increased from 48% to 60% (p=0.013). Rescue EMR after RFA decreased from 13% to 2% (p<0.0001). Progression to OAC at 12 months is not significantly different (3.6% vs 2.1%, p=0.51).

CONCLUSIONS

Clinical outcomes for BE neoplasia have improved significantly over the past 6 years with improved lesion recognition and aggressive resection of visible lesions before RFA. Despite advances in technique, the rate of cancer progression remains 2-4% at 1 year in these high-risk patients.

TRIAL REGISTRATION NUMBER

ISRCTN93069556.

Surveillance in patients with long-segment Barrett's oesophagus: a cost-effectiveness analysis

OBJECTIVE

Surveillance is recommended for Barrett's oesophagus (BO) to detect early oesophageal adenocarcinoma (OAC). The aim of this study was to evaluate the cost-effectiveness of surveillance.

DESIGN

We included 714 patients with long-segment BO in a multicentre prospective cohort study and used a multistate Markov model to calculate progression rates from no dysplasia (ND) to low-grade dysplasia (LGD), high-grade dysplasia (HGD) and OAC. Progression rates were incorporated in a decision-analytic model, including costs and quality of life data. We evaluated different surveillance intervals for ND and LGD, endoscopic mucosal resection (EMR), radiofrequency ablation (RFA) and oesophagectomy for HGD or early OAC and oesophagectomy for advanced OAC. The incremental cost-effectiveness ratio (ICER) was calculated in costs per quality-adjusted life-year (QALY).

RESULTS

The annual progression rate was 2% for ND to LGD, 4% for LGD to HGD or early OAC and 25% for HGD or early OAC to advanced OAC. Surveillance every 5 or 4 years with RFA for HGD or early OAC and oesophagectomy for advanced OAC had ICERs of €5.283 and €62.619 per QALY for ND. Surveillance every five to one year had ICERs of €4.922, €30.067, €32.531, €41.499 and €75.601 per QALY for LGD. EMR prior to RFA was slightly more expensive, but important for tumour staging.

CONCLUSIONS

Based on a Dutch healthcare perspective and assuming a willingness-to-pay threshold of €35.000 per QALY, surveillance with EMR and RFA for HGD or early OAC, and oesophagectomy for advanced OAC is cost-effective every 5 years for ND and every 3 years for LGD.

Barrett's oesophagus: how should we manage it?

Endoscopic surveillance remains the core management of non-dysplastic Barrett's oesophagus, although questions regarding its efficacy in reducing mortality from oesophageal adenocarcinoma have yet to be definitively answered, and randomised trial data are awaited. One of the main goals of current research is to achieve risk stratification, identifying those at high risk of progression. The recent British Society of Gastroenterology (BSG) guidelines on surveillance have taken a step in this direction with interval stratification on clinicopathological grounds. The majority of Barrett's oesophagus remains undiagnosed, and this has led to investigation of methods of screening for Barrett's oesophagus, ideally non-endoscopic methods capable of reliably identifying dysplasia. Chemoprevention to prevent progression is currently under investigation, and may become a key component of future treatment. The availability of effective endotherapy means that accurate identification of dysplasia is more important than ever. There is now evidence to support intervention with radiofrequency ablation (RFA) for low-grade dysplasia (LGD), but recent data have emphasised the need for consensus pathology for LGD. Ablative treatment has become well established for high-grade dysplasia, and should be employed for flat lesions where there is no visible abnormality. Of the ablative modalities, RFA has the strongest evidence base. Endoscopic resection should be performed for all visible lesions, and is now the treatment of choice for T1a tumours. Targeting those with high-risk disease will, hopefully, lead to efficacious and cost-effective surveillance, and the trend towards earlier intervention to halt progression gives cause for optimism that this will ultimately result in fewer deaths from oesophageal adenocarcinoma.

Oesophageal adenocarcinoma and prior diagnosis of Barrett's oesophagus: a population-based study

OBJECTIVE

Endoscopic surveillance of Barrett's oesophagus (BO) provides an opportunity to detect early stage oesophageal adenocarcinoma (OAC). We sought to determine the proportion of OAC patients with a prior diagnosis of BO on a population basis and to evaluate the influence of a prior diagnosis of BO on survival, taking into account lead and length time biases.

DESIGN

A retrospective population-based study of all OAC patients in Northern Ireland between 2003 and 2008. A prior BO diagnosis was determined by linkage to the Northern Ireland BO register. Stage distribution at diagnosis and histological grade were compared between patients with and without a prior BO diagnosis. Overall survival, using Cox models, was compared between patients with and without a prior BO diagnosis. The effect of adjusting the survival differences for histological grade and estimates of lead and length time bias was assessed.

RESULTS

There were 716 OAC cases, 52 (7.3%) of whom had a prior BO diagnosis. Patients with a prior BO diagnosis had significantly lower tumour stage (44.2% vs. 11.1% had stage 1 or 2 disease; p<0.001), a higher rate of surgical resection (50.0% vs. 25.5%; p<0.001) and had a higher proportion of low/intermediate grade tumours (46.2% vs. 26.5%; p=0.011). A prior BO diagnosis was associated with significantly better survival (HR for death 0.39; 95% CI 0.27 to 0.58), which was minimally influenced by adjustment for age, sex and tumour grade (adjusted HR 0.44; 95% CI 0.30 to 0.64). Correction for lead time bias attenuated but did not abolish the survival benefit (HR 0.65; 95% CI 0.45 to 0.95) and further adjustment for length time bias had little effect.

CONCLUSIONS

The proportion of OAC patients with a prior diagnosis of BO is low; however, prior identification of BO is associated with an improvement in survival in OAC patients.

The human squamous oesophagus has widespread capacity for clonal expansion from cells at diverse stages of differentiation

OBJECTIVE

Knowledge of the cellular mechanisms involved in homeostasis of human squamous oesophagus in the steady state and following chronic injury is limited. We aimed to better understand these mechanisms by using a functional 3D approach.

DESIGN

Proliferation, mitosis and the expression of progenitor lineage markers were assessed in normal squamous oesophagus from 10 patients by immunofluorescence on 3D epithelial whole mounts. Cells expressing differential levels of epithelial and progenitor markers were isolated using flow cytometry sorting and characterised by qPCR and IF. Their self-renewing potential was investigated by colony forming cells assays and in vitro organotypic culture models.

RESULTS

Proliferation and mitotic activity was highest in the interpapillary basal layer and decreased linearly towards the tip of the papilla (p<0.0001). The orientation of mitosis was random throughout the basal layer, and asymmetric divisions were not restricted to specific cell compartments. Cells sorted into distinct populations based on the expression of epithelial and progenitor cell markers (CD34 and EpCAM) showed no difference in self-renewal in 2D culture, either as whole populations or as single cells. In 3D organotypic cultures, all cell subtypes were able to recapitulate the architecture of the tissue of origin and the main factor determining the success of the 3D culture was the number of cells plated, rather than the cell type.

CONCLUSIONS

Oesophageal epithelial cells demonstrate remarkable plasticity for self-renewal. This situation could be viewed as an ex vivo wounding response and is compatible with recent findings in murine models.

Barrett's oesophagus: epidemiology, cancer risk and implications for management

Although endoscopic surveillance of patients with Barrett's oesophagus has been widely implemented, its effectiveness is debateable. The recently reported low annual oesophageal adenocarcinoma risk in population studies, the failure to identify most Barrett's patients at risk of disease progression, the poor adherence to surveillance and biopsy protocols, and the significant risk of misclassification of dysplasia all tend to undermine the effectiveness of current management, in particular, endoscopic surveillance programmes, to prevent or improve the outcomes of patients with oesophageal adenocarcinoma. The ongoing increase in incidence of Barrett's oesophagus and consequent growth of the surveillance population, together with the associated discomfort and costs of endoscopic surveillance, demand improved techniques for accurately determining individual risk of oesophageal adenocarcinoma. More accurate techniques are needed to run efficient surveillance programmes in the coming decades. In this review, we will discuss the current knowledge on the epidemiology of Barrett's oesophagus, and the challenging epidemiological dilemmas that need to be addressed when assessing the current screening and surveillance strategies.

British Society of Gastroenterology guidelines on the diagnosis and management of Barrett's oesophagus

These guidelines provide a practical and evidence-based resource for the management of patients with Barrett's oesophagus and related early neoplasia. The Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument was followed to provide a methodological strategy for the guideline development. A systematic review of the literature was performed for English language articles published up until December 2012 in order to address controversial issues in Barrett's oesophagus including definition, screening and diagnosis, surveillance, pathological grading for dysplasia, management of dysplasia, and early cancer including training requirements. The rigour and quality of the studies was evaluated using the SIGN checklist system. Recommendations on each topic were scored by each author using a five-tier system (A+, strong agreement, to D+, strongly disagree). Statements that failed to reach substantial agreement among authors, defined as >80% agreement (A or A+), were revisited and modified until substantial agreement (>80%) was reached. In formulating these guidelines, we took into consideration benefits and risks for the population and national health system, as well as patient perspectives. For the first time, we have suggested stratification of patients according to their estimated cancer risk based on clinical and histopathological criteria. In order to improve communication between clinicians, we recommend the use of minimum datasets for reporting endoscopic and pathological findings. We advocate endoscopic therapy for high-grade dysplasia and early cancer, which should be performed in high-volume centres. We hope that these guidelines will standardise and improve management for patients with Barrett's oesophagus and related neoplasia.