Detection of Barrett's oesophagus through exhaled breath using an electronic nose device

Application of electronic nose technology in the diagnosis of gastrointestinal diseases: a review

Electronic noses (eNoses) are electronic bionic olfactory systems that use sensor arrays to produce response patterns to different odors, thereby enabling the identification of various scents. Gastrointestinal diseases have a high incidence rate and occur in 9 out of 10 people in China. Gastrointestinal diseases are characterized by a long course of symptoms and are associated with treatment difficulties and recurrence. This review offers a comprehensive overview of volatile organic compounds, with a specific emphasis on those detected via the eNose system. Furthermore, this review describes the application of bionic eNose technology in the diagnosis and screening of gastrointestinal diseases based on recent local and international research progress and advancements. Moreover, the prospects of bionic eNose technology in the field of gastrointestinal disease diagnostics are discussed.

Overcoming the Limits of Cross-Sensitivity: Pattern Recognition Methods for Chemiresistive Gas Sensor Array

As information acquisition terminals for artificial olfaction, chemiresistive gas sensors are often troubled by their cross-sensitivity, and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing area. Pattern recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas sensors. It is crucial to choose an appropriate pattern recognition method for enhancing data analysis, reducing errors and improving system reliability, obtaining better classification or gas concentration prediction results. In this review, we analyze the sensing mechanism of cross-sensitivity for chemiresistive gas sensors. We further examine the types, working principles, characteristics, and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing arrays. Additionally, we report, summarize, and evaluate the outstanding and novel advancements in pattern recognition methods for gas identification. At the same time, this work showcases the recent advancements in utilizing these methods for gas identification, particularly within three crucial domains: ensuring food safety, monitoring the environment, and aiding in medical diagnosis. In conclusion, this study anticipates future research prospects by considering the existing landscape and challenges. It is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications.

Prospect and Challenges of Volatile Organic Compound Breath Testing in Non-Cancer Gastrointestinal Disorders

Breath analysis, despite being an overlooked biomatrix, has a rich history in disease diagnosis. However, volatile organic compounds (VOCs) have yet to establish themselves as clinically validated biomarkers for specific diseases. As focusing solely on late-stage or malignant disease biomarkers may have limited relevance in clinical practice, the objective of this review is to explore the potential of VOC breath tests for the diagnosis of non-cancer diseases: (1) Precancerous conditions like gastro-esophageal reflux disease (GERD) and Barrett's esophagus (BE), where breath tests can complement endoscopic screening; (2) endoluminal diseases associated with autoinflammation and dysbiosis, such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and coeliac disease, which currently rely on biopsy and symptom-based diagnosis; (3) chronic liver diseases like cirrhosis, hepatic encephalopathy, and non-alcoholic fatty liver disease, which lack non-invasive diagnostic tools for disease progression monitoring and prognostic assessment. A literature search was conducted through EMBASE, MEDLINE, and Cochrane databases, leading to an overview of 24 studies. The characteristics of these studies, including analytical platforms, disorder type and stage, group size, and performance evaluation parameters for diagnostic tests are discussed. Furthermore, how VOCs can be utilized as non-invasive diagnostic tools to complement existing gold standards is explored. By refining study designs, sampling procedures, and comparing VOCs in urine and blood, we can gain a deeper understanding of the metabolic pathways underlying VOCs. This will establish breath analysis as an effective non-invasive method for differential diagnosis and disease monitoring.

Improving esophageal cancer screening across the globe: Translating knowledge into action

Esophageal cancer (EC) is a pressing global health concern, ranking as the eighth most common cancer and the sixth leading cause for cancer-related deaths worldwide. Esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC) are the two major histological types of esophageal cancer associated with distinct risk factors and geographical distributions. Unfortunately, the outcomes for both types of EC remain discouraging, with a five-year survival rate of less than 20% when diagnosed at advanced stages. Advanced endoscopic techniques have the potential to vastly enhance patient outcomes and impede the progression of pre-malignant lesions to cancer. However, low screening rates with endoscopy due to its invasive nature and high cost hinder its effectiveness. Despite extensive research on risk predictors, a significant number of cases still go undiagnosed, highlighting the need for improved screening techniques that can be implemented at the population level. To increase uptake, a shift towards minimally invasive, well-tolerated and cost-effective non-endoscopic technologies is crucial. The implementation of such devices in primary care settings, specifically targeting high-risk populations, can be a promising strategy. With early detection and enrollment in surveillance programs, there is hope for substantial improvement in morbidity and mortality rates through modern minimally invasive endoscopic and surgical techniques.

Design and Evaluation of ScanCap: A Low-Cost, Reusable Tethered Capsule Endoscope with Blue-Green Illumination Imaging for Unsedated Screening and Early Detection of Barrett's Esophagus

Esophageal carcinoma is the sixth-leading cause of cancer death worldwide. A precursor to esophageal adenocarcinoma (EAC) is Barrett's Esophagus (BE). Early-stage diagnosis and treatment of esophageal neoplasia (Barrett's with high-grade dysplasia/intramucosal cancer) increase the five-year survival rate from 10% to 98%. BE is a global challenge; however, current endoscopes for early BE detection are costly and require extensive infrastructure for patient examination and sedation. We describe the design and evaluation of the first prototype of ScanCap, a high-resolution optical endoscopy system with a reusable, low-cost tethered capsule, designed to provide high-definition, blue-green illumination imaging for the early detection of BE in unsedated patients. The tethered capsule (12.8 mm diameter, 35.5 mm length) contains a color camera and rotating mirror and is designed to be swallowed; images are collected as the capsule is retracted manually via the tether. The tether provides electrical power and illumination at wavelengths of 415 nm and 565 nm and transmits data from the camera to a tablet. The ScanCap prototype capsule was used to image the oral mucosa in normal volunteers and ex vivo esophageal resections; images were compared to those obtained using an Olympus CV-180 endoscope. Images of superficial capillaries in intact oral mucosa were clearly visible in ScanCap images. Diagnostically relevant features of BE, including irregular Z-lines, distorted mucosa, and dilated vasculature, were clearly visible in ScanCap images of ex vivo esophageal specimens.

The Public's Intended Uptake of Hypothetical Esophageal Adenocarcinoma Screening Scenarios: A Nationwide Survey

INTRODUCTION

Screening for early esophageal adenocarcinoma (EAC) may potentially reduce EAC-related mortality and morbidity. This study aimed to examine the Dutch population's intended uptake of 3 hypothetical EAC screening test scenarios and preferences for potential future organization.

METHODS

A total of 8,350 Dutch individuals aged 45-75 years were invited, of whom 2,258 completed a web-based survey. Participants were randomly assigned to 1 of 3 hypothetical screening test scenarios (i.e., transnasal endoscopy, ingestible cell collection device, or breath analysis). The primary outcome was intended uptake. Secondary outcomes included acceptance of screening eligibility criteria and preferences regarding invitation, counseling, and diagnostic follow-up. We performed exploratory univariable and multivariable regression analyses to assess which determinants were associated with EAC screening intent.

RESULTS

Intended uptake of screening was highest in the breath analysis scenario (95%), followed by conventional upper endoscopy (78%), an ingestible cell collection device (75%), and transnasal endoscopy (68%) ( P < 0.001). Anticipating discomfort was most strongly associated with decreased intention to undergo transnasal endoscopy (odds ratio 0.18, 95% confidence interval 0.11-0.29) or swallow a cell collection device (odds ratio 0.20, 95% confidence interval 0.13-0.32). Cancer worry and high acceptance of test sensitivity/specificity were consistently associated with a positive intention to participate in screening. Inviting persons for screening based on gastroesophageal reflux disease symptoms, age, or the output of a risk prediction model was acceptable to 74%, 69%, and 66%, respectively. Inviting only men was acceptable for only 41% of women. The majority (58%) preferred to be invited by a public health organization, and 32% of the participants preferred to discuss their decision to participate with a healthcare professional.

DISCUSSION

Participants in this study self-selected through a web-based survey, potentially introducing selection bias. Participants generally intended to participate in EAC screening, although the level of intent depended on the discomfort and performance associated with the offered screening test. Determining eligibility based on gastroesophageal reflux disease symptoms, age, or a risk calculator, but not sex, would be acceptable to most individuals.

Advances in Screening for Barrett Esophagus and Esophageal Adenocarcinoma

Esophageal adenocarcinoma (EAC), the primary form of esophageal cancer in the United States, is a lethal cancer with exponentially increasing incidence. Screening for Barrett esophagus (BE), the only known precursor to EAC, followed by endoscopic surveillance to detect dysplasia and early-stage EAC and subsequent endoscopic treatment (to prevent progression of dysplasia to EAC and to treat early-stage EAC effectively) is recommended by several society guidelines. Sedated endoscopy (the primary current tool for BE screening) is both invasive and expensive, limiting its widespread use. In this review, we aim to provide a comprehensive review of recent innovations in the nonendoscopic detection of BE and EAC. These include swallowable cell sampling devices combined with protein and epigenetic biomarkers (which are now guideline endorsed as alternatives to sedated endoscopy), tethered capsule endomicroscopy, emerging peripheral blood-sampled molecular biomarkers, and exhaled volatile organic compounds. We also summarize progress and challenges in assessing BE and EAC risk, which is an important complementary component of the process for the clinical implementation of these innovative nonendoscopic tools, and propose a new paradigm for the strategy to reduce EAC incidence and mortality.

Dutch, UK and US professionals' perceptions of screening for Barrett's esophagus and esophageal adenocarcinoma: a concept mapping study

BACKGROUND

Novel, less-invasive technologies to screen for Barrett's esophagus (BE) may enable a paradigm shift in early detection strategies for esophageal adenocarcinoma (EAC). Understanding professionals' perspectives on screening is important to determine how to proceed. We aimed to explore and compare professionals' perceptions of screening for BE and EAC screening in three countries.

METHODS

In this study, 29 Dutch, 20 British and 18 American health care professionals (clinicians, researchers and policy makers) participated in concept mapping: a mixed-methods consensus building methodology. Statements on perceived barriers, facilitators, advantages, disadvantages, implications or worries associated with screening for BE and EAC were collected in asynchronous digital brainstorm sessions. Subsequently, participants sorted the statements into groups according to thematic similarity and assessed the relevance of each statement in evaluating the acceptability of BE and EAC screening. Multidimensional scaling and cluster analysis were used to map the associations between generated statements.

RESULTS

Professionals across three countries identified eight consistent themes that relate to their perceptions of screening for BE and EAC: (1) Benefits, (2) Harms, (3) Clinical effectiveness concerns, (4) Screening population, (5) Screening modality, (6) Resources, (7) Ownership, and (8) Public communication. Dutch and American professionals prioritized the potential health benefits of screening but also questioned clinical impact. In contrast, British participants prioritized identification of the screening population and suitable test.

CONCLUSIONS

Most professionals see potential in less-invasive screening tests for BE and EAC but underline the need to define the target screening population and determine benefits and harms before widely employing them. Successful implementation will require thoughtful consideration of the involvement of general practitioners, readiness of endoscopy and pathology services, balanced public communication, and country-specific regulations.

Molecular Biology and Clinical Management of Esophageal Adenocarcinoma

Esophageal adenocarcinoma (EAC) is a highly lethal malignancy. Due to its rising incidence, EAC has become a severe health challenge in Western countries. Current treatment strategies are mainly chosen based on disease stage and clinical features, whereas the biological background is hardly considered. In this study, we performed a comprehensive review of existing studies and discussed how etiology, genetics and epigenetic characteristics, together with the tumor microenvironment, contribute to the malignant behavior and dismal prognosis of EAC. During the development of EAC, several intestinal-type proteins and signaling cascades are induced. The anti-inflammatory and immunosuppressive microenvironment is associated with poor survival. The accumulation of somatic mutations at the early phase and chromosomal structural rearrangements at relatively later time points contribute to the dynamic and heterogeneous genetic landscape of EAC. EAC is also characterized by frequent DNA methylation and dysregulation of microRNAs. We summarize the findings of dysregulations of specific cytokines, chemokines and immune cells in the tumor microenvironment and conclude that DNA methylation and microRNAs vary with each different phase of BE, LGD, HGD, early EAC and invasive EAC. Furthermore, we discuss the suitability of the currently employed therapies in the clinic and possible new therapies in the future. The development of targeted and immune therapies has been hampered by the heterogeneous genetic characteristics of EAC. In view of this, the up-to-date knowledge revealed by this work is absolutely important for future EAC studies and the discovery of new therapeutics.

Research progress of electronic nose technology in exhaled breath disease analysis

Exhaled breath analysis has attracted considerable attention as a noninvasive and portable health diagnosis method due to numerous advantages, such as convenience, safety, simplicity, and avoidance of discomfort. Based on many studies, exhaled breath analysis is a promising medical detection technology capable of diagnosing different diseases by analyzing the concentration, type and other characteristics of specific gases. In the existing gas analysis technology, the electronic nose (eNose) analysis method has great advantages of high sensitivity, rapid response, real-time monitoring, ease of use and portability. Herein, this review is intended to provide an overview of the application of human exhaled breath components in disease diagnosis, existing breath testing technologies and the development and research status of electronic nose technology. In the electronic nose technology section, the three aspects of sensors, algorithms and existing systems are summarized in detail. Moreover, the related challenges and limitations involved in the abovementioned technologies are also discussed. Finally, the conclusion and perspective of eNose technology are presented.

Professionals' views on the justification for esophageal adenocarcinoma screening: A systematic literature search and qualitative analysis

Screening for early esophageal adenocarcinoma (EAC), including screening for its precursor Barrett's esophagus (BE), has the potential to reduce EAC-related mortality and morbidity. This literature review aimed to explore professionals' views on the justification for EAC screening. A systematic search of Ovid Medline, EMBASE, and PsycInfo, from January 1, 2000 to September 22, 2022, identified 5 original studies and 63 expert opinion articles reporting professionals' perspectives on EAC screening. Included articles were qualitatively analyzed using the framework method, which was deductively led by modernized screening principles. The analyses showed that many professionals are optimistic about technological advancements in BE detection and treatment. However, views on whether the societal burden of EAC merits screening were contradictory. In addition, knowledge of the long-term benefits and risks of EAC screening is still considered insufficient. There is no consensus on who to screen, how often to screen, which screening test to use, and how to manage non-dysplastic BE. Professionals further point out the need to develop technology that facilitates automated test sample processing and public education strategies that avoid causing disproportionately high cancer worry and social stigma. In conclusion, modernized screening principles are currently insufficiently fulfilled to justify widespread screening for EAC. Results from future clinical screening trials and risk prediction modeling studies may shift professionals' thoughts regarding justification for EAC screening.

Dutch individuals' views of screening for oesophageal cancer: a focus group study

OBJECTIVE

Screening for early oesophageal adenocarcinoma (OAC), including its precursor Barrett's oesophagus (BO), can potentially reduce OAC-related morbidity and mortality. This study explores Dutch at-risk individuals' views of screening an at-risk population for BO/OAC.

DESIGN

We invited 372 individuals with risk factors for OAC from primary care practices, 73 individuals with surveillance experience, and 221 participants of previous studies (BO/OAC screening trial or survey) to participate in focus groups. Transcripts were inductively and thematically analysed by two independent researchers.

RESULTS

A total of 50 individuals (42% with gastro-oesophageal reflux symptoms) of 50-75 years participated. Themes that were raised included: theme 1 'screening intentions' describing participants' motivation to be screened (eg, early diagnosis, potential reassurance, physician recommendation, and knowing someone with cancer) or decline screening (eg, anticipated discomfort or suboptimal accuracy of the test); theme 2 'risk-based eligibility' describing the tension between effectiveness (eg, targeting high-risk individuals) and inclusivity (eg, making screening available for everyone); theme 3 'distributive justice', in which the pressure of a potential new screening programme on healthcare resources was discussed; and theme 4 'information needs' describing the perceived lack of information access and individuals' preference to discuss screening with their general practitioner.

CONCLUSION

Individuals not only expressed high willingness to be screened but also voiced the concern that a new screening programme may pressure limited healthcare resources. If implemented, it is crucial to develop educational materials that meet the public's information needs and explain the test procedures and eligibility criteria while avoiding stigmatising language.

Management of Post Ablative Barrett's Esophagus: a Review of Current Practices and Look at Emerging Technologies

Purpose of review

Endoscopic eradication therapy is an effective and durable treatment for Barrett's esophagus (BE) related neoplasia, but even after achieving successful eradication, these patients remain at risk for recurrence and require ongoing routine examinations. The optimal surveillance protocol including endoscopic technique, sampling strategy, and timing are still being refined. The aim of this review is to discuss current management principles for the post ablation patient and emerging technologies to guide clinical practice.

Recent findings

There is increasing evidence to support less frequent surveillance exams in the first year after complete eradication of intestinal metaplasia and a move towards targeted biopsies of visible lesions and sampling high-risk locations such as the gastroesophageal junction. Promising technologies on the horizon that could impact management include novel biomarkers, personalized surveillance intervals, and non-endoscopic approaches.

Summary

Ongoing high-quality examinations after endoscopic eradication therapy are key to limiting recurrent BE. Surveillance intervals should be based on the pretreatment grade of dysplasia. Future research should focus on technologies and surveillance practices that are most efficient for patients and the healthcare system.

Diagnosing Non-Small Cell Lung Cancer by Exhaled Breath Profiling Using an Electronic Nose: A Multicenter Validation Study

BACKGROUND

Despite the potential of exhaled breath analysis of volatile organic compounds to diagnose lung cancer, clinical implementation has not been realized, partly due to the lack of validation studies.

RESEARCH QUESTION

This study addressed two questions. First, can we simultaneously train and validate a prediction model to distinguish patients with non-small cell lung cancer from non-lung cancer subjects based on exhaled breath patterns? Second, does addition of clinical variables to exhaled breath data improve the diagnosis of lung cancer?

STUDY DESIGN AND METHODS

In this multicenter study, subjects with non-small cell lung cancer and control subjects performed 5 min of tidal breathing through the aeoNose, a handheld electronic nose device. A training cohort was used for developing a prediction model based on breath data, and a blinded cohort was used for validation. Multivariable logistic regression analysis was performed, including breath data and clinical variables, in which the formula and cutoff value for the probability of lung cancer were applied to the validation data.

RESULTS

A total of 376 subjects formed the training set, and 199 subjects formed the validation set. The full training model (including exhaled breath data and clinical parameters from the training set) were combined in a multivariable logistic regression analysis, maintaining a cut off of 16% probability of lung cancer, resulting in a sensitivity of 95%, a specificity of 51%, and a negative predictive value of 94%; the area under the receiver-operating characteristic curve was 0.87. Performance of the prediction model on the validation cohort showed corresponding results with a sensitivity of 95%, a specificity of 49%, a negative predictive value of 94%, and an area under the receiver-operating characteristic curve of 0.86.

INTERPRETATION

Combining exhaled breath data and clinical variables in a multicenter, multi-device validation study can adequately distinguish patients with lung cancer from subjects without lung cancer in a noninvasive manner. This study paves the way to implement exhaled breath analysis in the daily practice of diagnosing lung cancer.

CLINICAL TRIAL REGISTRATION

The Netherlands Trial Register; No.: NL7025; URL: https://trialregister.nl/trial/7025.

Identification and validation of volatile organic compounds in bile for differential diagnosis of perihilar cholangiocarcinoma

Early and differential diagnosis of perihilar cholangiocarcinoma (PHCCA) is highly challenging. This study aimed to evaluate whether volatile organic compounds (VOCs) in bile samples could be emerging diagnostic biomarkers for PHCCA. We collected 200 bile samples from patients with PHCCA and benign biliary diseases (BBD), including a 140-patient training cohort and an 60-patient test cohort. Gas chromatography-ion mobility spectrometry (GC-IMS) was used for VOCs detection. The predictive models were constructed using machine learning algorithms. Our analysis detected 19 VOC substances using GC-IMS in the bile samples and resulted in the identification of three new VOCs, 2-methoxyfuran, propyl isovalerate, and diethyl malonate that were found in bile. Unsupervised hierarchical clustering analysis supported that VOCs detected in the bile could distinguish PHCCA from BBD. Twelve VOCs defined according to 32 signal peaks had significant statistical significance between BBD and PHCCA, including four up-regulated VOCs in PHCCA, such as 2-ethyl-1-hexanol, propyl isovalerate, cyclohexanone, and acetophenone, while the rest eight VOCs were down-regulated. ROC curve analysis revealed that machine learning models based on VOCs could help diagnosing PHCCA. Among them, SVM provided the highest AUC of 0·966, with a sensitivity and specificity of 93·1% and 100%, respectively. The diagnostic model based on different VOC spectra could be a feasible method for the differential diagnosis of PHCCA.

Expanding beyond endoscopy: A review of non-invasive modalities in Barrett’s esophagus screening and surveillance

Barrett’s esophagus (BE) is a condition that results from replacement of the damaged normal squamous esophageal mucosa to intestinal columnar mucosa and is the most significant predisposing factor for development of esophageal adenocarcinoma. Current guidelines recommend endoscopic evaluation for screening and surveillance based on various risk factors which has limitations such as invasiveness, availability of a trained specialist, patient logistics and cost. Trans-nasal endoscopy is a less invasive modality but still has similar limitations such as limited availability of trained specialist and costs. Non-endoscopic modalities, in comparison, require minimal intervention, can be done in an office visit and has the potential to be a more ideal choice for mass public screening and surveillance, particularly in patents at low risk for BE. These include newer generations of esophageal capsule endoscopy which provides direct visualization of BE, and tethered capsule endomicroscopy which can obtain high-resolution images of the esophagus. Various cell collection devices coupled with biomarkers have been used for BE screening. Cytosponge, in combination with TFF3, as well as EsophaCap and EsoCheck have shown promising results in various studies when used with various biomarkers. Other modalities including circulatory microRNAs and volatile organic compounds that have demonstrated favorable outcomes. Use of these cell collection methods for BE surveillance is a potential area of future research.

Limitations of Heartburn and Other Societies' Criteria in Barrett's Screening for Detecting De Novo Esophageal Adenocarcinoma

BACKGROUND & AIMS

Despite extensive Barrett's esophagus (BE) screening efforts, most patients with esophageal adenocarcinoma (EAC) present de novo. It is unclear how much of this problem is the result of insensitivity or poor applications of current screening guidelines. We aimed to evaluate the sensitivity of guidelines by determining the proportion of prevalent EAC cases that meet the American College of Gastroenterology (ACG) or the British Society of Gastroenterology (BSG) guidelines for BE screening and determine whether changes to criteria would enhance detection.

METHODS

A retrospective single-center cohort from the United States (n = 663) and a prospective multicenter cohort from the United Kingdom (n = 645) were collected and analyzed independently. Screening eligibility was determined as patients with chronic reflux and at least 2 or more risk factors as defined by the guidelines. We calculated the proportion of screening-eligible patients and then compared BE/EAC risk factors between screening-eligible and screening-ineligible patients using the chi-squared or Student t test as appropriate.

RESULTS

In the Mayo clinic cohort there were 54.9% EAC cases and in the UK cohort there were 38.9% EAC cases that were not identified by ACG or BSG screening criteria, respectively. Among patients who did not meet the screening criteria, lack of heartburn was observed in 86.5% in the Mayo clinic cohort and in 61.4% in the UK cohort. Other risk factors that were lacking included obesity (defined as a body mass index of ≥30 kg/m²) and family history of EAC. Eliminating chronic reflux from the ACG/BSG criteria improved eligibility for screening from 45.1% to 81.3% (P < .001) in the Mayo Clinic cohort and from 61.1% (n = 394) to 81.5% (n = 526; P < .001) in the UK cohort. However, reflux may be difficult to ascertain from the history, and by including proton pump inhibitor use status in addition to the BSG criteria, screening eligibility improved by 10.0% in the UK cohort (n = 459; P < .001).

CONCLUSIONS

ACG/BSG BE screening guidelines have limited our ability to detect prevalent EAC. An optimized approach to identifying the individuals most suitable for EAC screening needs to be implemented, particularly one that does not rely on chronic reflux symptoms.

Unsedated transnasal endoscopy for the detection of Barrett's esophagus: systematic review and meta-analysis

Conventional esophagogastroduodenoscopy (cEGD) is currently the gold standard endoscopic procedure for diagnosis and surveillance of Barrett's esophagus (BE). This procedure is however less suitable for widespread screening because of its invasiveness and costs. An alternative endoscopic procedure is unsedated transnasal endoscopy (uTNE). We performed a systematic review and meta-analysis to evaluate the diagnostic accuracy, patient tolerability, technical success rate, and safety of uTNE compared with cEGD for detecting BE and related neoplasia. PubMed, EMBASE, and Cochrane Library were searched for studies that reported the diagnostic accuracy of uTNE compared with cEGD for detecting BE and related neoplasia. Eight prospective studies were included, in which 623 patients underwent both uTNE and cEGD. Pooled sensitivity and specificity of uTNE for detecting columnar epithelium were 98% (95% CI 83-100%) and 99% (95% CI 82-100%), respectively. Pooled sensitivity and specificity of uTNE for detecting intestinal metaplasia in biopsies were 89% (95% CI 78-95%) and 93% (95% CI 71-98%), respectively. In three of the six studies that reported patient tolerability, a higher patient tolerability of uTNE compared with cEGD was reported. The technical success rate of uTNE ranged from 89% to 100% and no (serious) adverse events were reported. This systematic review and meta-analysis provides evidence that uTNE is an accurate, safe, and well-tolerated procedure for the detection of columnar epithelium and can be considered as screening modality for BE.

Detection of differentiated thyroid carcinoma in exhaled breath with an electronic nose

This proof-of-principle study investigates the diagnostic performance of the Aeonose in differentiating malignant from benign thyroid diseases based on volatile organic compound analysis in exhaled breath. All patients with a suspicious thyroid nodule planned for surgery, exhaled in the Aeonose. Definitive diagnosis was provided by histopathological determination after surgical resection. Breath samples were analyzed utilizing artificial neural networking. About 133 participants were included, 48 of whom were diagnosed with well-differentiated thyroid cancer. A sensitivity of 0.73 and a negative predictive value (NPV) of 0.82 were found. The sensitivity and NPV improved to 0.94 and 0.95 respectively after adding clinical variables via multivariate logistic regression analysis. This study demonstrates the feasibility of the Aeonose to discriminate between malignant and benign thyroid disease. With a high NPV, low cost, and non-invasive nature, the Aeonose may be a promising diagnostic tool in the detection of thyroid cancer.

Age-specific incidence, treatment, and survival trends in esophageal cancer: a Dutch population-based cohort study

BACKGROUND

Data on the age-specific incidence of esophageal cancer are lacking. Our aim was to investigate the age-stratified incidence, treatment, and survival trends of esophageal cancer in the Netherlands, with a focus on adults <50 years.

MATERIAL AND METHODS

Patients diagnosed with esophageal cancer were included from the nationwide Netherlands Cancer Registry (1989-2018). Follow-up data were available until 31 December 2018. Annual percentage changes of incidence were analyzed according to age group (<50, 50-74, and ≥75 years) and histology type: adenocarcinoma (EAC) and squamous cell carcinoma (ESCC). Treatment trends and relative survival rates (RSR) were estimated by age and stage grouping.

RESULTS

A total 59,584 patients were included. In adults <50 years, EAC incidence tripled (mean increase per year: males 1.5%, females 3%), while the incidence of ESCC decreased (mean decrease per year: males -5.3%, females -4.3%). Patients <50 years more often presented with advanced disease stages compared to older patients and were more likely to receive multimodality treatments. Most patients <50 years with potentially curable disease were treated with neoadjuvant chemoradiotherapy followed by surgery compared to patients 50-74 and ≥75 years (74% vs. 55% vs. 15%, respectively; p < .001), and received more frequent systemic therapy once staged with palliative disease (72% vs. 54% vs. 19%, respectively; p < .001). The largest RSR improvement was seen in patients <50 years with early-stage (five years: +47%), potentially curable (five years: +22%), and palliative disease (one year: +11%). Over time, a trend of increasing survival difference was seen between patients <50 and ≥75 years with potentially curable (five-year difference: 17% to 27%) and palliative disease (one-year difference: 11% to 20%).

CONCLUSION

The incidence of EAC is increasing in adults <50 years in the Netherlands. Differences in the use of multimodality treatments with curative or life-prolonging intent in different age categories may account for increasing survival gaps.

Artificial Intelligence in the Management of Barrett’s Esophagus and Early Esophageal Adenocarcinoma

Simple Summary

Esophageal adenocarcinoma is increasing in incidence and is the most common subtype of esophageal cancer in Western societies. AI systems are currently under development and validation in many fields of gas-troenterology.

Abstract

Esophageal adenocarcinoma is increasing in incidence and is the most common subtype of esophageal cancer in Western societies. The stepwise progression of Barrett´s metaplasia to high-grade dysplasia and invasive adenocarcinoma provides an opportunity for screening and surveillance. There are important unresolved issues, which include (i) refining the definition of the screening population in order to avoid unnecessary invasive diagnostics, (ii) a more precise prediction of the (very heterogeneous) individual progression risk from metaplasia to invasive cancer in order to better tailor surveillance recommendations, (iii) improvement of the quality of endoscopy in order to reduce the high miss rate for early neoplastic lesions, and (iv) support for the diagnosis of tumor infiltration depth in order to guide treatment decisions. Artificial intelligence (AI) systems might be useful as a support to better solve the above-mentioned issues.

Public acceptance and uptake of oesophageal adenocarcinoma screening strategies: A mixed-methods systematic review

Oesophageal adenocarcinoma (OAC) is increasingly diagnosed and often fatal, thus representing a growing global health concern. Screening for its precursor, Barrett's oesophagus (BO), combined with endoscopic surveillance and treatment of dysplasia might prevent OAC. This review aimed to systematically explore the public's acceptance and uptake of novel screening strategies for OAC. We systematically searched three electronic databases (Ovid Medline/PubMed, Ovid EMBASE and PsycINFO) from date of inception to July 2, 2021 and hand-searched references to identify original studies published in English on acceptability and uptake of OAC screening. Two reviewers independently reviewed and appraised retrieved records and two reviewers extracted data (verified by one other reviewer). Of the 3674 unique records, 19 studies with 15 249 participants were included in the review. Thematic analysis of findings showed that acceptability of OAC screening is related to disease awareness, fear, belief in benefit, practicalities and physical discomfort. The findings were mapped on the Integrated Screening Action Model. Minimally invasive screening tests are generally well-tolerated: patient-reported outcomes were reported for sedated upper endoscopy (tolerability ++), transnasal endoscopy (tolerability +), tethered capsule endomicroscopy (tolerability +/-), and the Cytosponge-TFF3 test (acceptability ++). In discrete choice experiments, individuals mainly valued screening test accuracy. OAC screening has been performed in trials using conventional upper endoscopy (n = 231 individuals), transnasal endoscopy (n = 966), capsule endoscopy (n = 657) and the Cytosponge-TFF3 test (n = 9679), with uptake ranging from 14·5% to 48·1%. Intended participation in OAC screening in questionnaire-based studies ranged from 62·8% to 71·4%. We conclude that the general public seems to have interest in OAC screening. The findings will provide input for the design of a screening strategy that incorporates the public's values and preferences to improve informed participation. Identification of a screening strategy effective in reducing OAC mortality and morbidity remains a crucial prerequisite.

FUNDING

This study was funded by the Netherlands Organization for Health Research and Development (ZonMw) under grant 555,004,206.

Diagnosis and Management of Barrett's Esophagus: An Updated ACG Guideline

Barrett's esophagus (BE) is a common condition associated with chronic gastroesophageal reflux disease. BE is the only known precursor to esophageal adenocarcinoma, a highly lethal cancer with an increasing incidence over the last 5 decades. These revised guidelines implement Grading of Recommendations, Assessment, Development, and Evaluation methodology to propose recommendations for the definition and diagnosis of BE, screening for BE and esophageal adenocarcinoma, surveillance of patients with known BE, and the medical and endoscopic treatment of BE and its associated early neoplasia. Important changes since the previous iteration of this guideline include a broadening of acceptable screening modalities for BE to include nonendoscopic methods, liberalized intervals for surveillance of short-segment BE, and volume criteria for endoscopic therapy centers for BE. We recommend endoscopic eradication therapy for patients with BE and high-grade dysplasia and those with BE and low-grade dysplasia. We propose structured surveillance intervals for patients with dysplastic BE after successful ablation based on the baseline degree of dysplasia. We could not make recommendations regarding chemoprevention or use of biomarkers in routine practice due to insufficient data.

Applying the electronic nose for pre-operative SARS-CoV-2 screening

BACKGROUND

Infection with SARS-CoV-2 causes corona virus disease (COVID-19). The most standard diagnostic method is reverse transcription-polymerase chain reaction (RT-PCR) on a nasopharyngeal and/or an oropharyngeal swab. The high occurrence of false-negative results due to the non-presence of SARS-CoV-2 in the oropharyngeal environment renders this sampling method not ideal. Therefore, a new sampling device is desirable. This proof-of-principle study investigated the possibility to train machine-learning classifiers with an electronic nose (Aeonose) to differentiate between COVID-19-positive and negative persons based on volatile organic compounds (VOCs) analysis.

METHODS

Between April and June 2020, participants were invited for breath analysis when a swab for RT-PCR was collected. If the RT-PCR resulted negative, the presence of SARS-CoV-2-specific antibodies was checked to confirm the negative result. All participants breathed through the Aeonose for five minutes. This device contains metal-oxide sensors that change in conductivity upon reaction with VOCs in exhaled breath. These conductivity changes are input data for machine learning and used for pattern recognition. The result is a value between - 1 and + 1, indicating the infection probability.

RESULTS

219 participants were included, 57 of which COVID-19 positive. A sensitivity of 0.86 and a negative predictive value (NPV) of 0.92 were found. Adding clinical variables to machine-learning classifier via multivariate logistic regression analysis, the NPV improved to 0.96.

CONCLUSIONS

The Aeonose can distinguish COVID-19 positive from negative participants based on VOC patterns in exhaled breath with a high NPV. The Aeonose might be a promising, non-invasive, and low-cost triage tool for excluding SARS-CoV-2 infection in patients elected for surgery.

Barrett's Esophagus: Diagnosis, Management, and Key Updates

Barrett's esophagus (BE) is the precursor lesion for esophageal adenocarcinoma (EAC) development. Unfortunately, BE screening/surveillance has not provided the anticipated EAC reduction benefit. Noninvasive techniques are increasingly available or undergoing testing to screen for BE among those with/without known risk factors, and the use of artificial intelligence platforms to aid endoscopic screening and surveillance will likely become routine, minimizing missed cases or lesions. Management of high-grade dysplasia and intramucosal EAC is clear with endoscopic eradication therapy preferred to surgery. BE with low-grade dysplasia can be managed with removal of visible lesions combined with endoscopic eradication therapy or endoscopic surveillance at present.

Innovations in Screening Tools for Barrett's Esophagus and Esophageal Adenocarcinoma

PURPOSE OF REVIEW

Esophageal adenocarcinoma (EAC) is a lethal disease with rapidly rising incidence. Screening for EAC and its metaplastic precursor, Barrett's esophagus (BE), followed by endoscopic surveillance and endoscopic treatment of dysplasia or early EAC are promising approaches to decreasing EAC incidence and EAC mortality. Historically, screening for EAC has been completed with a traditional per-oral esophagogastroduodenoscopy (EGD); however, this method has limitations including cost, tolerability, and accessibility. For this reason, much effort has been put forward to develop more effective, minimally invasive, and accessible BE and EAC screening tools. The purpose of this review is to describe recent developments of these novel tools.

RECENT FINDINGS

While endoscopic alternatives such as transnasal endoscopy are cheaper and well tolerated, they have not gained acceptance. Non-endoscopic modalities namely, swallowable cell collection devices coupled with biomarker analysis have been found to have excellent performance characteristics, tolerability, and cost effectiveness. In this article, we provide an update on innovative developments in EAC/BE screening modalities including transnasal endoscopy, capsule endomicroscopy, swallowable cell collection devices, and exhaled volatile organic compound analyses.

Trends and projections in the incidence of oesophageal cancer in the Netherlands: An age-period-cohort analysis from 1989 to 2041

In Western populations, the incidence of oesophageal squamous cell carcinoma (OSCC) has been declining, whereas the incidence of oesophageal adenocarcinoma (OAC) has been increasing. Our study examines temporal trends in the incidence of oesophageal cancer in the Netherlands between 1989 and 2016, in addition to predicting future trends through 2041. Data from the Netherlands Cancer Registry and Statistics Netherlands were collected to obtain incidence trends of OSCC and OAC for the period 1989 to 2016. Age‐period‐cohort (APC) modelling was used to estimate the contribution of age, calendar period and birth cohort on the observed incidence trends. To predict the future numbers of new cases of both OSCC and OAC from 2017 to 2041, log‐linear APC models were fitted to the trends of 1989 to 2016. The age‐standardised incidence rates of OSCC have decreased slightly for men and increased slightly for women. In contrast, a marked increase in the incidence of OAC was observed, ranging from 2.8 per 100 000 persons in 1989 to 10.1 in 2016. This increase in OAC incidence was more prominent in men, and it will result in an increased risk of OAC for successive generations. Future projections indicate that the incidence of OAC will further increase to 13.1 per 100 000 persons in 2037 to 2041, meaning that there will be 13 259 cases of OAC in 2037 to 2041, as compared to 9386 diagnoses in 2017 to 2021. The changing epidemiologic trends in oesophageal cancer in the Netherlands should be reflected in the development of prevention, early detection and treatment strategies.

What's new?

The incidence of esophageal adenocarcinoma (OAC) is on the rise in Western countries. Better understanding of this trend could facilitate critical improvements in OAC prevention, early detection, and treatment strategies. Here, the authors investigated trends in OAC incidence from 1989 to 2016 for successive birth cohorts in the Netherlands. OAC incidence was found to have increased significantly since 1989, with risk rising most noticeably in men. Analyses through 2037‐2041 predict continued growth in OAC cases. The findings highlight the importance of promoting measures to prevent esophageal cancer, particularly those aimed at controlling modifiable risk factors, such as obesity and smoking.

Systematic review with meta-analysis: the effects of family history on the risk of Barrett's oesophagus and oesophageal adenocarcinoma

BACKGROUND

Current guidelines recommend different screening approaches for individuals with a family history of Barrett's oesophagus (BO) or oesophageal adenocarcinoma (OAC), varying from no screening to screening all individuals with a positive family history.

AIMS

To determine evidence-based risk estimates for individuals with a family history of BO or OAC METHODS: We systematically searched Pubmed, Embase and Cochrane Library until October 2020 to identify all studies that reported on the association between family history and the risk of BO and OAC. Pooled summary estimates of adjusted relative risks and prevalence of familial BO/OAC with 95% confidence intervals (CIs) were calculated using a random effects model.

RESULTS

Fourteen studies comprising 16 189 BO/OAC patients were analysed. Familial clustering was seen in 8.84% (95% CI: 5.54-13.82) and 4.37% (95% CI: 2.15-8.69) of patients with BO and OAC, respectively (nine studies). Screening first-degree relatives of BO patients had a diagnostic yield between 12% and 44% for BO (four studies). However, the yield for high-grade dysplasia and OAC was low (<2%). Individuals with a positive family history had a higher risk of having BO (aRR 3.26; 95% CI 1.43-7.40; I²  = 46%; three studies) and OAC (aRR 2.19; 95% CI 1.14-4.21; I²  = 48%; five studies) compared to individuals without a family history.

CONCLUSIONS

A verified family history of BO or OAC is a strong risk factor for both BO and OAC. A positive family history could be a clinically meaningful way to identify high-risk individuals who may benefit from early detection strategies.

Assessment of Breathomics Testing Using High-Pressure Photon Ionization Time-of-Flight Mass Spectrometry to Detect Esophageal Cancer

IMPORTANCE

A triage test is needed to increase the detection rate for esophageal cancer.

OBJECTIVE

To investigate whether breathomics can detect esophageal cancer among patients without a previous diagnosis of cancer using high-pressure photon ionization time-of-flight mass spectrometry (HPPI-TOFMS).

DESIGN, SETTING, AND PARTICIPANTS

This diagnostic study included participants who planned to receive an upper endoscopy or surgery of the esophagus at a single center in China. Exhaled breath was collected with a self-designed collector and air bags before participants underwent these procedures. Sample collection and analyses were performed by trained researchers following a standardized protocol. Participants were randomly divided into a discovery data set and a validation data set. Data were collected from December 2020 to March 2021.

EXPOSURES

Breath samples were analyzed by HPPI-TOFMS, and the support vector machine algorithm was used to construct a detection model.

MAIN OUTCOMES AND MEASURES

The accuracy of breathomics was measured by the sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve.

RESULTS

Exhaled breath samples were obtained from 675 patients (216 [32%] with esophageal cancer; 459 [68%] with noncancer diseases). Of all patients, 206 (31%) were women, and the mean (SD) age was 64.0 (11.9) years. In the validation data set, esophageal cancer was detected with an accuracy of 93.33%, sensitivity of 97.83%, specificity of 83.72%, positive predictive value of 94.74%, negative predictive value of 92.78%, and area under the receiver operating characteristic curve of 0.89. Notably, for 16 patients with high-grade intraepithelial neoplasia, 12 (75%) were predicted to have esophageal cancer.

CONCLUSIONS AND RELEVANCE

In this diagnostic study, testing breathomics using HPPI-TOFMS was feasible for esophageal cancer detection and totally noninvasive, which could help to improve the diagnosis of esophageal cancer.

Validation of a methylated DNA marker panel for the nonendoscopic detection of Barrett's esophagus in a multisite case-control study

BACKGROUND AND AIMS

We previously identified a 5 methylated DNA marker (MDM) panel for the detection of nonendoscopic Barrett's esophagus (BE). In this study, we aimed to recalibrate the performance of the 5 MDM panel using a simplified assay in a training cohort, validate the panel in an independent test cohort, and explore the accuracy of an MDM panel with only 3 markers.

METHODS

Participants were recruited from 3 medical centers. The sponge on a string device (EsophaCap; CapNostics, Concord, NC, USA) was swallowed and withdrawn, followed by endoscopy, in BE cases and control subjects. A 5 MDM panel was blindly assayed using a simplified assay. Random forest modeling analysis was performed, in silico cross-validated in the training set, and then locked down, before test set analysis.

RESULTS

The training set had 199 patients: 110 BE cases and 89 control subjects, and the test set had 89 patients: 60 BE cases and 29 control subjects. Sensitivity of the 5 MDM panel for BE diagnosis was 93% at 90% specificity in the training set and 93% at 93% specificity in the test set. Areas under the receiver operating characteristic curves were .96 and .97 in the training and test sets, respectively. Model accuracy was not influenced by age, sex, or smoking history. Multiple 3 MDM panels achieved similar accuracy.

CONCLUSIONS

A 5 MDM panel for BE is highly accurate in training and test sets in a blinded multisite case-control analysis using a simplified assay. This panel may be reduced to only 3 MDMs in the future. (Clinical trial registration number: NCT02560623.).

Increased risk of Barrett's oesophagus and related neoplasia in individuals with a positive family history

BACKGROUND

Considering the poor prognosis of oesophageal adenocarcinoma (EAC), it is important to identify individuals at increased risk of developing EAC who may benefit from early detection and prevention strategies. We aimed to determine whether individuals with a positive family history of Barrett's oesophagus (BE) and EAC are at an increased risk of oesophageal neoplasia.

METHODS

In a multi-centre case-control study, BE patients with or without related oesophageal neoplasia and randomly selected population controls filled out a questionnaire to collect information on family history and other risk factors for BE and EAC. Positive family history was defined as having ≥1 first-degree relative with BE or EAC whose diagnosis was histologically confirmed in the Dutch nationwide histopathology database.

FINDINGS

We included 480 BE patients and 420 controls without BE who had a total of 6393 first-degree relatives. A pathologically confirmed positive family history was significantly higher in BE patients compared with controls (6.5% versus 0.9; p < 0.001). Positive family history was independently associated with an increased risk of BE (OR 5.04; 95% CI 1.45-17.58; p = 0.01) after adjusting for known risk factors, such as gastroesophageal reflux disease and body mass index, and family size.

INTERPRETATION

We found that familial clustering of BE and EAC is present in 6.5% of Dutch BE patients. Subjects with ≥1 first-degree relative with BE or EAC have a 5-fold increased risk of BE and EAC. These findings emphasize the importance of a detailed family history in patients with BE or EAC to identify individuals at increased risk who may benefit from early detection strategies to prevent EAC-related mortality.

Comparative Cost Effectiveness of Reflux-Based and Reflux-Independent Strategies for Barrett's Esophagus Screening

INTRODUCTION

Minimally invasive tests for Barrett's esophagus (BE) detection have raised the prospect of broader nonreflux-based testing. Cost-effectiveness studies have largely studied men aged 50 years with chronic gastroesophageal reflux disease (GERD) symptoms. We evaluated the comparative cost effectiveness of BE screening tests in GERD-based and GERD-independent testing scenarios.

METHODS

Markov modeling was performed in 3 scenarios in 50 years old individuals: (i) White men with chronic GERD (GERD-based); (ii) GERD-independent (all races, men and women), BE prevalence 1.6%; and (iii) GERD-independent, BE prevalence 5%. The simulation compared multiple screening strategies with no screening: sedated endoscopy (sEGD), transnasal endoscopy, swallowable esophageal cell collection devices with biomarkers, and exhaled volatile organic compounds. A hypothetical cohort of 500,000 individuals followed for 40 years using a willingness to pay threshold of $100,000 per quality-adjusted life year (QALY) was simulated. Incremental cost-effectiveness ratios (ICERs) comparing each strategy with no screening and comparing screening strategies with each other were calculated.

RESULTS

In both GERD-independent scenarios, most non-sEGD BE screening tests were cost effective. Swallowable esophageal cell collection devices with biomarkers were cost effective (<$35,000/QALY) and were the optimal screening tests in all scenarios. Exhaled volatile organic compounds had the highest ICERs in all scenarios. ICERs were low (<$25,000/QALY) for all tests in the GERD-based scenario, and all non-sEGD tests dominated no screening. ICERs were sensitive to BE prevalence and test costs.

DISCUSSION

Minimally invasive nonendoscopic tests may make GERD-independent BE screening cost effective. Participation rates for these strategies need to be studied.

Public Preferences and Predicted Uptake for Esophageal Cancer Screening Strategies: A Labeled Discrete Choice Experiment

INTRODUCTION:

As novel, less invasive (non)endoscopic techniques for detection of Barrett's esophagus (BE) have been developed, there is now renewed interest in screening for BE and related neoplasia. We aimed to determine public preferences for esophageal adenocarcinoma screening to understand the potential of minimally invasive screening modalities.

METHODS:

A discrete choice experiment was conducted in 1,500 individuals, aged 50–75 years, from the general population. Individuals were repeatedly asked to choose between screening scenarios based on conventional upper endoscopy, transnasal endoscopy, nonendoscopic cell collection devices, breath analysis, and a blood test, combined with various levels of test sensitivity and specificity, and no screening. A multinomial logit model was used to estimate individuals' preferences and to calculate expected participation rates.

RESULTS:

In total, 554 respondents (36.9%) completed the survey. The average predicted uptake was 70.5% (95% confidence interval: 69.1%–71.8%). Test sensitivity (47.7%), screening technique (32.6%), and specificity (19.7%) affected screening participation (all P < 0.05). A low test sensitivity had the highest impact on screening participation, resulting in a 25.0% (95% confidence interval: 22.6%–27.7%) decrease. Respondents preferred noninvasive screening tests over endoscopic and capsule-based techniques, but only if sensitivity and specificity were above 80%.

DISCUSSION:

Our study suggests that individuals generally prefer noninvasive BE screening tests. However, these tests would unlikely improve screening uptake when associated with a much lower accuracy for detecting BE and esophageal adenocarcinoma compared with conventional upper endoscopy. Improving accuracy of minimally invasive screening strategies and informing the target population about these accuracies is therefore essential to maximally stimulate screening participation.

Breath analysis for the detection of digestive tract malignancies: systematic review

Background

In recent decades there has been growing interest in the use of volatile organic compounds (VOCs) in exhaled breath as biomarkers for the diagnosis of multiple variants of cancer. This review aimed to evaluate the diagnostic accuracy and current status of VOC analysis in exhaled breath for the detection of cancer in the digestive tract.

Methods

PubMed and the Cochrane Library database were searched for VOC analysis studies, in which exhaled air was used to detect gastro-oesophageal, liver, pancreatic, and intestinal cancer in humans, Quality assessment was performed using the QUADAS-2 criteria. Data on diagnostic performance, VOCs with discriminative power, and methodological information were extracted from the included articles.

Results

Twenty-three articles were included (gastro-oesophageal cancer n = 14, liver cancer n = 1, pancreatic cancer n = 2, colorectal cancer n = 6). Methodological issues included different modalities of patient preparation and sampling and platform used. The sensitivity and specificity of VOC analysis ranged from 66.7 to 100 per cent and from 48.1 to 97.9 per cent respectively. Owing to heterogeneity of the studies, no pooling of the results could be performed. Of the VOCs found, 32 were identified in more than one study. Nineteen were reported as cancer type-specific, whereas 13 were found in different cancer types. Overall, decanal, nonanal, and acetone were the most frequently identified.

Conclusion

The literature on VOC analysis has documented a lack of standardization in study designs. Heterogeneity between the studies and insufficient validation of the results make interpretation of the outcomes challenging. To reach clinical applicability, future studies on breath analysis should provide an accurate description of the methodology and validate their findings.

Screening for Barrett's Oesophagus: Are We Ready for it?

Purpose of review

The targeted approach adopted for Barrett’s oesophagus (BO) screening is sub-optimal considering the large proportion of BO cases that are currently missed. We reviewed the literature highlighting recent technological advancements in efforts to counteract this challenge. We also provided insights into strategies that can improve the outcomes from current BO screening practises.

Recent findings

The standard method for BO detection, endoscopy, is invasive and expensive and therefore inappropriate for mass screening. On the other hand, endoscopy is more cost-effective for screening a high-risk population. A consensus has however not been reached on who should be screened. Risk prediction algorithms have been tested as an enrichment pre-screening tool reporting modest AUC’s but require more prospective evaluation studies. Less invasive endoscopy methods like trans-nasal endoscopy, oesophageal capsule endsocopy and non-endoscopic cell collection devices like the Cytosponge coupled with biomarker analysis have shown promise in BO detection with randomised clinical trial evidence.

Summary

A three-tier precision cancer programme whereby risk prediction algorithms and non-endoscopic minimally invasive cell collection devices are used to triage test a wider pool of individuals may improve the detection rate of current screening practises with minimal cost implications.

Current Trends in Endoscopic Diagnosis and Treatment of Early Esophageal Cancer

Simple Summary

Early esophageal cancer is diagnosed in the context of reflux disease, surveillance of Barrett’s metaplasia, or during upper gastrointestinal endoscopy for other indications. High definition and virtual or dye chromoendoscopy are mandatory for the screening and evaluation of neoplasia. Endoscopic treatment options include endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD). Resection is considered curative if histopathology confirms low or absent risk of lymph node metastasis. Barrett’s high-grade dysplasia or early adenocarcinoma is treated by EMR or ESD, followed by ablation of Barrett’s epithelium to avoid metachronous cancer. ESD is the treatment of choice for squamous cell neoplasia. Excellent outcomes have been reported if the ESD of squamous cell cancer with slight submucosal infiltration and thus substantial risk for lymph node metastasis was combined with adjuvant chemo-radiotherapy. In contrast, infiltration of squamous cell cancer exceeding the lamina propria mucosae is not curative. However, despite a substantial risk of lymph node metastasis, excellent outcomes have recently been reported if endoscopic resection of tumors with up to 200 µm submucosal infiltration was combined with adjuvant chemo-radiotherapy.

Abstract

Diagnosis of esophageal adenocarcinoma mostly occurs in the context of reflux disease or surveillance of Barrett’s metaplasia. Optimal detection rates are obtained with high definition and virtual or dye chromoendoscopy. Smaller lesions can be treated with endoscopic mucosal resection. Endoscopic submucosal dissection (ESD) is an option for larger lesions. Endoscopic resection is considered curative (i.e., without significant risk of lymph node metastasis) if histopathology confirms en bloc and R0 resection of a well-differentiated (G1/2) tumor without infiltration of lymphatic or blood vessels and the maximal submucosal infiltration depth is 500µm. Ablation of remaining Barrett’s metaplasia is important, to reduce the risk of metachronous cancer. Esophageal squamous cell cancer is associated with different risk factors, and most of the detected lesions are diagnosed during upper gastrointestinal endoscopy for other indications. Virtual high definition and dye chromoendoscopy with Lugol’s solution are used for screening and evaluation. ESD is the preferred resection technique. The criteria for curative resection are similar to Barrett’s cancer, but the maximum infiltration depth must not exceed lamina propria mucosae. Although a submucosal infiltration depth of up to 200 µm carries a substantial risk of lymph node metastasis, ESD combined with adjuvant chemo-radiotherapy gives excellent results. The complication rates of endoscopic resection are low, and the functional outcomes are favorable compared to surgery.

Progress in Screening for Barrett's Esophagus: Beyond Standard Upper Endoscopy

The rapid increase in the incidence of esophageal adenocarcinoma in Western populations over the past 4 decades and its associated poor prognosis, unless detected early has generated great interest in screening for the precursor lesion Barrett's esophagus (BE). Recently, there have been significant developments in imaging-based modalities and esophageal cell-sampling devices coupled with biomarker assays. In this review, the authors discuss the rationale for screening for BE and the factors to consider for targeting the at-risk population. They also explore future avenues for research in this area.

Potential of the Electronic Nose for the Detection of Respiratory Diseases with and without Infection

Respiratory tract infections are common, and when affecting the lower airways and lungs, can result in significant morbidity and mortality. There is an unfilled need for simple, non-invasive tools that can be used to screen for such infections at the clinical point of care. The electronic nose (eNose) is a novel technology that detects volatile organic compounds (VOCs). Early studies have shown that certain diseases and infections can result in characteristic changes in VOC profiles in the exhaled breath. This review summarizes current knowledge on breath analysis by the electronic nose and its potential for the detection of respiratory diseases with and without infection.

Individuals' Preferences for Esophageal Cancer Screening: A Discrete Choice Experiment

OBJECTIVES

The increasing incidence of esophageal adenocarcinoma (EAC) and the dismal prognosis has stimulated interest in the early detection of EAC. Our objective was to determine individuals' preferences for EAC screening and to assess to what extent procedural characteristics of EAC screening tests predict willingness for screening participation.

METHODS

A discrete choice experiment questionnaire was sent by postal mail to 1000 subjects aged 50 to 75 years who were randomly selected from the municipal registry in the Netherlands. Each subject answered 12 discrete choice questions of 2 hypothetical screening tests comprising 5 attributes: EAC-related mortality risk reduction, procedure-related pain and discomfort, screening location, test specificity, and costs. A multinomial logit model was used to estimate individuals' preferences for each attribute level and to calculate expected rates of uptake.

RESULTS

In total, 375 individuals (37.5%) completed the questionnaire. Test specificity, pain and discomfort, mortality reduction, and out-of-pocket costs all had a significant impact on respondents' preferences. The average expected uptake of EAC screening was 62.8% (95% confidence interval [CI] 61.1-64.5). Severe pain and discomfort had the largest impact on screening uptake (-22.8%; 95% CI -26.8 to -18.7). Male gender (β 2.81; P < .001), cancer worries (β 1.96; P = .01), endoscopy experience (β 1.46; P = .05), and upper gastrointestinal symptoms (β 1.50; P = .05) were significantly associated with screening participation.

CONCLUSIONS

EAC screening implementation should consider patient preferences to maximize screening attendance uptake. Based on our results, an optimal screening test should have high specificity, cause no or mild to moderate pain or discomfort, and result in a decrease in EAC-related mortality.