Screening for high-grade dysplasia in gastroesophageal reflux disease: is it cost-effective?

Value of oesophagoscopy and bronchoscopy in diagnosis of synchronous malignancies in patients with head and neck squamous cell carcinomas

Background

Routine screening of patients with head and neck squamous cell carcinomas (HNSCCs) for synchronous malignancies using oesophagoscopy and bronchoscopy had been controversial. The aim of this study is therefore to find out the rate of synchronous malignancies in patients with primary HNSCCs, the risk factors for its occurrence and the effectiveness of oesophagoscopy and bronchoscopy from a 10-year experience in a single centre.

Methods

A retrospective review of medical records was conducted from July 2008 to June 2018 in a tertiary referral centre in Hong Kong. All patients with newly diagnosed HNSCCs were screened with oesophagoscopy and bronchoscopy at the time of diagnosis and therefore all patients were included in the study. The incidence of synchronous malignancies along the aerodigestive tract and the yield of oesophagoscopy and bronchoscopy were studied.

Results

Of the 702 patients included in the study, the overall rate of synchronous malignancies was 8.3% (58/702), with the rate of synchronous oesophageal and lung malignancies being 5.8% (41/702) and 0.85% (6/702) respectively. Fourteen out of the 41 oesophageal malignancies were only detectable with oesophagoscopy. Only one of the synchronous lung malignancies was detectable by bronchoscopy. Risk factors for synchronous malignancies include male gender, smokers, drinkers and primary hypopharyngeal cancer.

Conclusions

Oesophagoscopy is essential for detecting synchronous oesophageal malignancies in patients with HNSCCs especially in male patients, smokers and drinkers, and it is most valuable in primary hypopharyngeal cancer patients among all primary subsites. Bronchoscopy had a low yield for synchronous lung malignancies and can be potentially replaced by imaging techniques.

Screening for Barrett's Esophagus: Balancing Clinical Value and Cost-effectiveness

In predisposed individuals with long standing gastroesophageal reflux disease (GERD), esophageal squamous mucosa can transform into columnar mucosa with intestinal metaplasia, commonly called Barrett’s esophagus (BE). Barrett’s mucosa can develop dysplasia, which can be a precursor for esophageal adenocarcinoma (EAC). However, most EAC cases are identified when esophageal symptoms develop, without prior BE or GERD diagnoses. While several gastrointestinal societies have published BE screening guidelines, these vary, and many recommendations are not based on high quality evidence. These guidelines are concordant in recommending targeted screening of predisposed individuals (eg, long standing GERD symptoms with age > 50 years, male sex, Caucasian race, obesity, and family history of BE or EAC), and against population based screening, or screening of GERD patients without risk factors. Targeted endoscopic screening programs provide earlier diagnosis of high grade dysplasia and EAC, and offer potential for endoscopic therapy, which can improve prognosis and outcome. On the other hand, endoscopic screening of the general population, unselected GERD patients, patients with significant comorbidities or patients with limited life expectancy is not cost-effective. New screening modalities, some of which do not require endoscopy, have the potential to reduce costs and expand access to screening for BE.

Methylation Biomarker Panel Performance in EsophaCap Cytology Samples for Diagnosing Barrett's Esophagus: A Prospective Validation Study

PURPOSE

Barrett's esophagus is the only known precursor of esophageal adenocarcinoma (EAC). Although endoscopy and biopsy are standard methods for Barrett's esophagus diagnosis, their high cost and risk limit their use as a screening modality. Here, we sought to develop a Barrett's esophagus detection method based on methylation status in cytology samples captured by EsophaCap using a streamlined sensitive technique, methylation on beads (MOB).

EXPERIMENTAL DESIGN

We conducted a prospective cohort study on 80 patients (52 in the training set; 28 in the test set). We used MOB to extract and bisulfite-convert DNA, followed by quantitative methylation-specific PCR to assess methylation levels of 8 previously selected candidate markers. Lasso regression was applied to establish a prediction model in the training set, which was then tested on the independent test set.

RESULTS

In the training set, five of eight candidate methylation biomarkers (p16, HPP1, NELL1, TAC1, and AKAP12) were significantly higher in Barrett's esophagus patients than in controls. We built a four-biomarker-plus-age lasso regression model for Barrett's esophagus diagnosis. The AUC was 0.894, with sensitivity 94.4% [95% confidence interval (CI), 71%-99%] and specificity 62.2% (95% CI, 44.6%-77.3%) in the training set. This model also performed with high accuracy for Barrett's esophagus diagnosis in an independent test set: AUC = 0.929 (P < 0.001; 95% CI, 0.810%-1%), with sensitivity=78.6% (95% CI, 48.8%-94.3%) and specificity = 92.8% (95% CI, 64.1%-99.6%).

CONCLUSIONS

EsophaCap, in combination with an epigenetic biomarker panel and the MOB method, is a promising, well-tolerated, low-cost esophageal sampling strategy for Barrett's esophagus diagnosis. This approach merits further prospective studies in larger populations.

Identification and structural characterization of the stress degradation products of omeprazole using Q-TOF-LC-ESI-MS/MS and NMR experiments: evaluation of the toxicity of the degradation products

Omeprazole (OMP), a prototype proton pump inhibitor used for the treatment of peptic ulcers and gastroesophageal reflux disease (GERD), was subjected to forced degradation studies as per ICH guidelines Q1A (R2).

Tethered capsule endomicroscopy for microscopic imaging of the esophagus, stomach, and duodenum without sedation in humans (with video)

BACKGROUND AND AIMS

Patients with many different digestive diseases undergo repeated EGDs throughout their lives. Tethered capsule endomicroscopy (TCE) is a less-invasive method for obtaining high-resolution images of the GI mucosa for diagnosis and treatment planning of GI tract diseases. In this article, we present our results from a single-center study aimed at testing the safety and feasibility of TCE for imaging the esophagus, stomach, and duodenum.

METHODS

After being swallowed by a participant without sedation, the tethered capsule obtains cross-sectional, 10 μm-resolution, optical coherence tomography images as the device traverses the alimentary tract. After imaging, the device is withdrawn through the mouth, disinfected, and reused. Safety and feasibility of TCE were tested, focusing on imaging the esophagus of healthy volunteers and patients with Barrett's esophagus (BE) and the duodenum of healthy volunteers. Images were compared with endoscopy and histopathology findings when available.

RESULTS

Thirty-eight patients were enrolled. No adverse effects were reported. The TCE device swallowing rate was 34 of 38 (89%). The appearance of a physiologic upper GI wall, including its microscopic pathology, was visualized with a tissue coverage of 85.4% ± 14.9% and 90.3% ± 6.8% in the esophagus of BE patients with and without endoscopic evidence of a hiatal hernia, respectively, as well as 84.8% ± 7.4% in the duodenum. A blinded comparison of TCE and endoscopic BE measurements showed a strong to very strong correlation (r = 0.7-0.83; P < .05) for circumferential extent and a strong correlation (r = 0.77-0.78; P < .01) for maximum extent (Prague classification). TCE interobserver correlation was very strong, at r = 0.92 and r = 0.84 (P < .01), for Prague classification circumferential (C) and maximal (M) length measurements, respectively.

CONCLUSIONS

TCE is a safe and feasible procedure for obtaining high-resolution microscopic images of the upper GI tract without endoscopic assistance or sedation.

Barrett’s oesophagus: Current controversies

Oesophageal adenocarcinoma is rapidly increasing in Western countries. This tumour frequently presents late in its course with metastatic disease and has a very poor prognosis. Barrett’s oesophagus is an acquired condition whereby the native squamous mucosa of the lower oesophagus is replaced by columnar epithelium following prolonged gastro-oesophageal reflux and is the recognised precursor lesion for oesophageal adenocarcinoma. There are multiple national and society guidelines regarding screening, surveillance and management of Barrett’s oesophagus, however all are limited regarding a clear evidence base for a well-demonstrated benefit and cost-effectiveness of surveillance, and robust risk stratification for patients to best use resources. Currently the accepted risk factors upon which surveillance intervals and interventions are based are Barrett’s segment length and histological interpretation of the systematic biopsies. Further patient risk factors including other demographic features, smoking, gender, obesity, ethnicity, patient age, biomarkers and endoscopic adjuncts remain under consideration and are discussed in full. Recent evidence has been published to support earlier endoscopic intervention by means of ablation of the metaplastic Barrett’s segment when the earliest signs of dysplasia are detected. Further work should concentrate on establishing better risk stratification and primary and secondary preventative strategies to reduce the risk of adenocarcinoma of the oesophagus.

High-resolution microendoscopy for esophageal cancer screening in China: A cost-effectiveness analysis

AIM

To study the cost-effectiveness of high-resolution microendoscopy (HRME) in an esophageal squamous cell carcinoma (ESCC) screening program in China.

METHODS

A decision analytic Markov model of ESCC was developed. Separate model analyses were conducted for cohorts consisting of an average-risk population or a high-risk population in China. Hypothetical 50-year-old individuals were followed until age 80 or death. We compared three different strategies for both cohorts: (1) no screening; (2) standard endoscopic screening with Lugol's iodine staining; and (3) endoscopic screening with Lugol's iodine staining and an HRME. Model parameters were estimated from the literature as well as from GLOBOCAN, the Cancer Incidence and Mortality Worldwide cancer database. Health states in the model included non-neoplasia, mild dysplasia, moderate dysplasia, high-grade dysplasia, intramucosal carcinoma, operable cancer, inoperable cancer, and death. Separate ESCC incidence transition rates were generated for the average-risk and high-risk populations. Costs in Chinese currency were converted to international dollars (I$) and were adjusted to 2012 dollars using the Consumer Price Index.

RESULTS

The main outcome measurements for this study were quality-adjusted life years (QALYs) and incremental cost-effectiveness ratio (ICER). For the average-risk population, the HRME screening strategy produced 0.043 more QALYs than the no screening strategy at an additional cost of I$646, resulting in an ICER of I$11808 per QALY gained. Standard endoscopic screening was weakly dominated. Among the high-risk population, when the HRME screening strategy was compared with the standard screening strategy, the ICER was I$8173 per QALY. For both the high-risk and average-risk screening populations, the HRME screening strategy appeared to be the most cost-effective strategy, producing ICERs below the willingness-to-pay threshold, I$23500 per QALY. One-way sensitivity analysis showed that, for the average-risk population, higher specificity of Lugol's iodine (> 40%) and lower specificity of HRME (< 70%) could make Lugol's iodine screening cost-effective. For the high-risk population, the results of the model were not substantially affected by varying the follow-up rate after Lugol's iodine screening, Lugol's iodine test characteristics (sensitivity and specificity), or HRME specificity.

CONCLUSION

The incorporation of HRME into an ESCC screening program could be cost-effective in China. Larger studies of HRME performance are needed to confirm these findings.

Screening for Barrett's Esophagus

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

Cost considerations in implementing a screening and surveillance strategy for Barrett's oesophagus

There is increasing concern over the rising costs of healthcare leading to debate regarding the use of resources to implement preventive strategies. Oesophageal adenocarcinoma and its precursor, Barrett's oesophagus provides an excellent opportunity to highlight this issue since cancer is uncommon even among individuals with documented Barrett's oesophagus. This review provides a brief introduction to economic analysis in healthcare and summarizes published studies of the cost-effectiveness of strategies to reduce mortality from cancer. Current best estimates highlight the cost-effectiveness of endoscopic ablation among patients with Barrett's oesophagus and high-grade dysplasia and the low cost-effectiveness of ablation among patients without dysplasia. The cost-effectiveness of ablation among patients with Barrett's and low-grade dysplasia is poorly defined due to the ambiguity of diagnosing dysplasia, the unknown risk of cancer among patients with low-grade dysplasia, and the uncertain durability of ablation to maintain remission from metaplasia and dysplasia and prevent cancer.

Preference of endoscopic ablation over medical prevention of esophageal adenocarcinoma by patients with Barrett's esophagus

BACKGROUND & AIMS

Endoscopic intervention or pharmacologic inhibition of cyclooxygenase might be used to prevent progression of Barrett's esophagus (BE) to esophageal adenocarcinoma (EAC). We investigated whether patients with BE prefer endoscopic therapy or chemoprevention of EAC.

METHODS

Eighty-one subjects with nondysplastic BE were given a survey that described 2 scenarios. The survey explained that treatment A (ablation), endoscopy, reduced lifetime risk of EAC by 50%, with 5% risk for esophageal stricture, whereas treatment B (aspirin) reduced lifetime risk of EAC by 50% and the risk of heart attack by 30%, yet increased the risk for ulcer by 75%. Subjects indicated their willingness to undergo either treatment A and/or treatment B if endoscopic surveillance were required every 3-5 years, every 10 years, or were not required. Visual aids were included to represent risk and benefit percentages.

RESULTS

When surveillance was required every 3-5 years, more subjects were willing to undergo treatment A than treatment B (78%, 63 of 81 vs 53%, 43 of 81; P < .01). There were no differences in age, sex, education level, or history of cancer, heart disease, or ulcer between patients willing to undergo treatment A and those willing to undergo treatment B. Altering the frequency of surveillance did not affect patients' willingness to undergo either treatment.

CONCLUSIONS

In a simulated scenario, patients with BE preferred endoscopic intervention over chemoprevention for EAC. Further investigation of the shared decision-making process regarding preventive strategies for patients with BE may be warranted.

Evidence-based endoscopic management of Barrett's esophagus

Barrett’s esophagus (BE) develops as a consequence of chronic esophageal acid exposure, and is the major risk factor for esophageal adenocarcinoma (EAC). The practices of endoscopic screening for—and surveillance of—BE, while widespread, have failed to reduce the incidence of EAC. The majority of EACs are diagnosed in patients without a known history of BE, and current diagnostic tools are lacking in their ability to stratify patients with BE into those at low risk and those at high risk for progression to malignancy. Nonetheless, advances in endoscopic imaging and mucosal therapeutics have provided unprecedented opportunities for intervention for BE, and have vastly altered the approach to management of BE-associated mucosal neoplasia.

Statins and aspirin for chemoprevention in Barrett's esophagus: results of a cost-effectiveness analysis

Data suggest that aspirin, statins, or a combination of the two drugs may lower the progression of Barrett's esophagus to esophageal adenocarcinoma. However, aspirin is associated with potential complications such as gastrointestinal bleeding and hemorrhagic stroke, and statins are associated with myopathy. We developed a simulation disease model to study the effectiveness and cost effectiveness of aspirin and statin chemoprevention against esophageal adenocarcinoma. A decision analytic Markov model was constructed to compare four strategies for Barrett's esophagus management; all regimens included standard endoscopic surveillance regimens: (i) endoscopic surveillance alone, (ii) aspirin therapy, (iii) statin therapy, and (iv) combination therapy of aspirin and statin. Endpoints evaluated were life expectancy, quality-adjusted life years (QALY), costs, and incremental cost-effectiveness ratios (ICER). Sensitivity analysis was performed to determine the impact of model input uncertainty on results. Assuming an annual progression rate of 0.33% per year from Barrett's esophagus to esophageal adenocarcinoma, aspirin therapy was more effective and cost less than (dominated) endoscopic surveillance alone. When combination therapy was compared with aspirin therapy, the ICER was $158,000/QALY, which was above our willingness-to-pay threshold of $100,000/QALY. Statin therapy was dominated by combination therapy. When higher annual cancer progression rates were assumed in the model (0.5% per year), combination therapy was cost-effective compared with aspirin therapy, producing an ICER of $96,000/QALY. In conclusion, aspirin chemoprevention was both more effective and cost less than endoscopic surveillance alone. Combination therapy using both aspirin and statin is expensive but could be cost-effective in patients at higher risk of progression to esophageal adenocarcinoma.

Screening for oesophageal cancer

BACKGROUND

Oesophageal cancer is a global heath problem. The prognosis for advanced oesophageal cancer is generally unfavourable, but early-stage asymptomatic oesophageal cancer is basically curable and could achieve better survival rates. The two most commonly used tests are cytologic examination and endoscopy with mucosal iodine staining. The efficacy of the screening tests is controversial, and the true benefit and efficacy of screening remains uncertain because of the potential lead-time and length-time biases. This review was conducted to examine the evidence for the efficacy of screening for oesophageal cancer (squamous cell carcinoma and adenocarcinoma).

OBJECTIVES

To determine the efficacy of early screening, using endoscopy with iodine staining or cytologic examination, in reducing mortality from oesophageal cancer in asymptomatic individuals from high-risk and general populations.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2012, Issue 8), The Cochrane Library (2012, Issue 8), MEDLINE (1950 to August 2012), EMBASE (1980 to August 2012), Allied and Complementary Medicine (AMED) (1985 to August 2012), Chinese Biomedical Database (CBM) (January 1975 to August 2012), VIP Database (January 1989 to August 2012), China National Knowledge Infrastructure (CNKI) (January 1979 to August 2012), and the Internet. We also searched reference lists, conference proceedings, and databases of ongoing trials. There was no restriction on language or publication status in the search for trials.

SELECTION CRITERIA

We included only randomised controlled trials (RCT) of screening versus no screening for oesophageal cancer. Randomisation of groups or clusters of individuals was acceptable.

DATA COLLECTION AND ANALYSIS

Two review authors independently scanned the titles and abstracts from the initial search for potential trials for inclusion. We did not find any trials that met the inclusion criteria.

MAIN RESULTS

The electronic search identified 3482 studies. Two authors independently reviewed the references. The reports of 18 studies were retrieved for further investigation. None met the eligibility criteria for a RCT investigation of the effects of screening versus no screening for oesophageal cancer.

AUTHORS' CONCLUSIONS

There were no RCTs that determined the efficacy of screening for oesophageal cancer. Non-RCTs showed a high incidence and the reported better survival after screening could be caused by selection bias, lead-time and length-time biases. RCTs are needed to determine the efficacy of screening for oesophageal cancer.

The cost effectiveness of radiofrequency ablation for Barrett's esophagus

BACKGROUND & AIMS

Radiofrequency ablation (RFA) reduces the risk of esophageal adenocarcinoma (EAC) in patients with Barrett's esophagus (BE) with high-grade dysplasia (HGD), but its effects in patients without dysplasia are debatable. We analyzed the effectiveness and cost effectiveness of RFA for the management of BE.

METHODS

We constructed a decision analytic Markov model. We conducted separate analyses of hypothetical cohorts of patients with BE with dysplasia (HGD or low-grade [LGD]) and without dysplasia. In the analysis of the group with HGD, we compared results of initial RFA with endoscopic surveillance with surgery when cancer was detected. In analyzing the group with LGD or no dysplasia, we compared 3 strategies: endoscopic surveillance with surgery when cancer was detected (S1), endoscopic surveillance with RFA when HGD was detected (S2), and initial RFA followed by endoscopic surveillance (S3).

RESULTS

Among patients with HGD, initial RFA was more effective and less costly than endoscopic surveillance. Among patients with LGD, when S3 was compared with S2, the incremental cost-effectiveness ratio was $18,231/quality-adjusted life-year, assuming an annual rate of progression rate from LGD to EAC of 0.5%/year. For patients without dysplasia, S2 was more effective and less costly than S1. In a comparison of S3 with S2, the incremental cost-effectiveness ratios were $205,500, $124,796, and $118,338/quality-adjusted life-year using annual rates of progression of no dysplasia to EAC of 0.12%, 0.33%, or 0.5% per year, respectively.

CONCLUSIONS

By using updated data, initial RFA might not be cost effective for patients with BE without dysplasia, within the range of plausible rates of progression of BE to EAC, and be prohibitively expensive, from a policy perspective. RFA might be cost effective for confirmed and stable LGD. Initial RFA is more effective and less costly than endoscopic surveillance in HGD.

Management of cancer risk in Barrett's esophagus

The importance of Barrett's esophagus (BE) lies in its potential to give rise to esophageal adenocarcinoma (EAC), postulated to be through a series of progressive degrees of dysplasia; from intestinal metaplasia to low-grade dysplasia, high-grade dysplasia, and subsequently, to cancer. The management strategies for the detection and treatment of dysplasia and early esophageal cancer on a background of BE have changed significantly in the last few decades, with the emergence of newer and less invasive non-operative alternatives. This review aims to outline BE and its relation to EAC, the rationale and cost-effectiveness of both screening and surveillance programs, methods of diagnosing and identifying dysplasia and early cancer in Barrett's, and approaches to individualizing their endoscopic and surgical management based on best-available staging techniques.

Developing a nonendoscopic screening test for Barrett's esophagus

Barrett's esophagus (BE) arises as a complication of chronic gastro-esophageal reflux disease and is the precursor lesion for esophageal adenocarcinoma. The prevalence of esophageal adenocarcinoma has been increasing in Western countries and the overall prognosis from this cancer remains dismal. Surveillance for BE is highly controversial since although early cancer detection through surveillance programs benefits individuals, surveillance has not been proven to reduce population mortality from the disease. One factor contributing to this apparent paradox is that an estimated >80% cases of BE are undiagnosed and, therefore, do not have the benefit of surveillance. Some form of screening modality is required to achieve more comprehensive detection of BE, which in turn, may lead to early detection of cancerous lesions and early intervention in order to reduce progression to invasive and symptomatic cancer. The advent of endoscopic therapy makes this paradigm attractive. A number of methods could be considered for screening. These include a nonendoscopic sampling method using a Cytosponge that needs to be coupled with a biomarker to obtain required levels of sensitivity and specificity. For screening to be recommended consideration needs to be given to the point of delivery, cost and acceptability to patients.

Treatment for Barrett's oesophagus

BACKGROUND

Treatments for Barrett's oesophagus, the precursor lesion of adenocarcinoma, are available but whether these therapies effectively prevent the development of adenocarcinoma, and in some cases eradicate the Barrett's oesophagus segment, remains unclear.

OBJECTIVES

To summarise, quantify and compare the efficacy of pharmacological, surgical and endoscopic treatments for the eradication of dysplastic and non-dysplastic Barrett's oesophagus and prevention of these states from progression to adenocarcinoma.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2004, issue 4), MEDLINE (1966 to June 2008) and EMBASE (1980 to June 2008).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing medical, endoscopic or non-resectional surgical treatments for Barrett's oesophagus. The primary outcome measures were complete eradication of Barrett's and dysplasia at 12 months, and reduction in the number of patients progressing to cancer at five years or latest time point.

DATA COLLECTION AND ANALYSIS

Three authors independently extracted data and assessed the quality of the trials included in the analysis.

MAIN RESULTS

Sixteen studies, including 1074 patients, were included. The mean number of participants in the studies was small (n = 49; range 8 to 208). Most studies did not report on the primary outcomes. Medical and surgical interventions to reduce symptoms and sequelae of gastro-oesophageal reflux disease (GORD) did not induce significant eradication of Barrett's oesophagus or dysplasia. Endoscopic therapies (photodynamic therapy (PDT with aminolevulinic acid or porfimer sodium), argon plasma coagulation (APC) and radiofrequency ablation (RFA)) all induced regression of Barrett's oesophagus and dysplasia. The data for photodynamic therapy were heterogeneous with a mean eradication rate of 51% for Barrett's oesophagus and between 56% and 100% for dysplasia, depending on the treatment regimens. The variation in photodynamic therapy eradication rates for dysplasia was dependent on the drug, source and dose of light. Radiofrequency ablation resulted in eradication rates of 82% and 94% for Barrett's oesophagus and dysplasia respectively, compared to a sham treatment. Endoscopic treatments were generally well tolerated, however all were associated with some buried glands, particularly following argon plasma coagulation and photodynamic therapy, as well as photosensitivity and strictures induced by porfimer sodium based photodynamic therapy in particular.

AUTHORS' CONCLUSIONS

Despite their failure to eradicate Barrett's oesophagus, the role of medical and surgical interventions to reduce the troubling symptoms and sequelae of GORD is not questioned. Whether therapies for GORD reduce the cancer risk is not yet known. Ablative therapies have an increasing role in the management of dysplasia within Barrett's and current data would favour the use of radiofrequency ablation compared with photodynamic therapy. Radiofrequency ablation has been shown to yield significantly fewer complications than photodynamic therapy and is very efficacious at eradicating both dysplasia and Barrett's itself. However, long-term follow-up data are still needed before radiofrequency ablation can be used in routine clinical care without the need for very careful post-treatment surveillance. More clinical trial data and in particular randomised controlled trials are required to assess whether or not the cancer risk is reduced in routine clinical practice.

Age- and sex-specific yield of Barrett's esophagus by endoscopy indication

BACKGROUND

Barrett's esophagus is a precursor of esophageal adenocarcinoma, both of which are associated with GERD. Screening GERD patients for Barrett's esophagus has been suggested, but it is not known which patients should be screened and at what age.

OBJECTIVE

To determine the age-specific yield of endoscopy for Barrett's esophagus stratified by sex and indication for endoscopy.

DESIGN

Retrospective cross-sectional study.

SETTING

National Endoscopic Database of the Clinical Outcomes Research Initiative (CORI).

PATIENTS

A total of 155,641 patients undergoing their first endoscopy at one of the CORI sites for clinical indications.

MAIN OUTCOME MEASUREMENTS

Age-specific yield of Barrett's esophagus.

RESULTS

Among white men with GERD, the yield of Barrett's esophagus increases steeply from early adulthood (2.1% in the third decade of life) to middle adulthood (9.3% in the sixth decade) and then plateaus (the difference for the eighth decade minus the sixth decade is -1.1%; 95% CI, -3.9% to 1.7%). There is no difference in the yield of Barrett's esophagus between middle-aged white women with GERD and white men without GERD (difference is -0.46%; 95% CI, -1.23% to 0.31%).

LIMITATIONS

Possible bias by selection for endoscopy and the potential for misclassification of GERD status.

CONCLUSIONS

The yield of upper endoscopy for the diagnosis of Barrett's esophagus increases rapidly among white men with GERD until approximately age 50 and then reaches a plateau. White women with GERD are at no increased risk compared with white men without GERD.

Cost-effectiveness of endoscopic screening followed by surveillance for Barrett's esophagus: a review

Screening interventions for Barrett's esophagus (BE) are appealing, but there is little supporting evidence. We reviewed health economics studies about BE endoscopic screening followed by, as required, endoscopic surveillance ("screening and surveillance" hereafter) to help inform the design and conduct of future research. Health economics studies about BE screening and surveillance were identified using electronic database searches and personal contact with authors of identified studies. No studies examined general population screening. Five US studies published between 2003 and 2007 examined the cost effectiveness of screening and surveillance (against no intervention) in patients with chronic gastroesophageal reflux disease (GERD). There was no randomized trial evidence to inform model construction. Assumptions about prevalence and transition probabilities between BE histologic subtypes and about surveillance and treatment protocols varied substantially between studies. Parameters such as potential BE diagnosis-related reduction in quality of life or increase in health care use, diagnostic accuracy, and infrastructural costs (for quality assurance) were considered either "optimistically" or not at all. Only 2 studies considered endoscopic treatments. No study considered the recently introduced radiofrequency ablation technique, or the potential for biomarker-based risk stratification of surveillance interval or duration. Current health economics evidence is likely to have provided optimistic cost-effectiveness estimates and is not sufficient to support introduction of endoscopic BE screening programs among GERD patients. The evidence does not adequately incorporate novel (endoscopic) treatments and the potential for (clinical, endoscopic, or biomarker-based) risk stratification of surveillance. Future research should aim to encompass both these factors.

A cost-utility analysis of ablative therapy for Barrett's esophagus

BACKGROUND & AIMS

Recommendations for patients with Barrett's esophagus (BE) include endoscopic surveillance with esophagectomy for early-stage cancer, although new technologies to ablate dysplasia and metaplasia are available. This study compares the cost utility of ablation with that of endoscopic surveillance strategies.

METHODS

A decision analysis model was created to examine a population of patients with BE (mean age 50), with separate analyses for patients with no dysplasia, low-grade dysplasia (LGD), or high-grade dysplasia (HGD). Strategies compared were no endoscopic surveillance; endoscopic surveillance with ablation for incident dysplasia; immediate ablation followed by endoscopic surveillance in all patients or limited to patients in whom metaplasia persisted; and esophagectomy. Ablation modalities modeled included radiofrequency, argon plasma coagulation, multipolar electrocoagulation, and photodynamic therapy.

RESULTS

Endoscopic ablation for patients with HGD could increase life expectancy by 3 quality-adjusted years at an incremental cost of <$6,000 compared with no intervention. Patients with LGD or no dysplasia can also be optimally managed with ablation, but continued surveillance after eradication of metaplasia is expensive. If ablation permanently eradicates >or=28% of LGD or 40% of nondysplastic metaplasia, ablation would be preferred to surveillance.

CONCLUSIONS

Endoscopic ablation could be the preferred strategy for managing patients with BE with HGD. Ablation might also be preferred in subjects with LGD or no dysplasia, but the cost effectiveness depends on the long-term effectiveness of ablation and whether surveillance endoscopy can be discontinued after successful ablation. As further postablation data become available, the optimal management strategy will be clarified.

Barrett's oesophagus

Barrett's oesophagus is a metaplastic change of the lining of the oesophagus, such that the normal squamous epithelium is replaced by specialised or intestinalised columnar epithelium. The disorder seems to be a complication of chronic gastro-oesophageal reflux disease, although asymptomatic individuals might also be affected, and it is a risk factor for the development of oesophageal adenocarcinoma, a cancer with rapidly increasing incidence in developed societies. We review the presentation, epidemiology, and risk factors for this condition. We discuss the molecular changes necessary for the development of Barrett's oesophagus and its progression to cancer, and new strides in both the endoscopic detection of the lesion and the treatment of dysplastic disease. Also, we assess the effectiveness of efforts to screen patients at risk of Barrett's oesophagus, and whether such efforts avert cancer death. We conclude with a discussion of future directions for research, focusing on treatment of early neoplasia, and modifications of current practices to show our evolving understanding of this condition.

Screening, surveillance, and prevention for esophageal cancer

The incidence of esophageal cancer, especially esophageal adenocarcinoma, is increasing and its high mortality rate is a notable fact. Improving survival rates of this disease depend on earlier detection through screening and surveillance; however, standard diagnostic modalities, such as endoscopy with biopsy, have several limitations as screening tools, including low negative predictive value and relatively high cost. Recently developed biomarkers such as FISH and improved imaging techniques, may help overcome current problems and provide improved screening and surveillance for esophageal cancer.

Should patients with Barrett's oesophagus be kept under surveillance? The case for

Oesophageal adenocarcinoma is associated with high mortality rates and its incidence is increasing more rapidly than any other gastrointestinal cancer in the Western world. Several factors, including gastro-oesophageal reflux disease, smoking, alcohol and male gender, are associated with oesophageal adenocarcinoma but none can be used to identify accurately those individuals who will develop adenocarcinoma. It is generally accepted that oesophageal adenocarcinoma arises predominantly in Barrett's oesophagus and it is arguable that Barrett's oesophagus is currently the only clinically useful predictor of oesophageal adenocarcinoma. Surveillance - periodic testing to detect adenocarcinoma or its precursor, high grade dysplasia - is widely recommended for patients with Barrett's oesophagus with the aim of reducing mortality from oesophageal adenocarcinoma. The annual incidence of oesophageal adenocarcinoma in patients with Barrett's oesophagus is 0.5%-1.0% although there is marked variation between studies, attributable variously to publication bias, concurrent acid suppression therapy and differences in patient characteristics. There is limited evidence that surveillance reduces the incidence of oesophageal adenocarcinoma or consequent mortality and the cause of death for patients undergoing surveillance is often unrelated to oesophageal disease. There are, nonetheless, observational studies which suggest that surveillance is associated with earlier detection of malignancy and a reduction in mortality; in addition, data from modelling studies suggest that surveillance can be cost-effective. Furthermore, the advent of new, non-surgical treatments (endoscopic mucosal resection, photodynamic therapy, argon plasma coagulation) for high grade dysplasia and early cancer has reduced the risks associated with therapy for disease detected during surveillance. Surveillance programs have high drop out rates and, for patients who continue surveillance, adherence to standard, published protocols is highly variable. The establishment of specialist Barrett's oesophagus surveillance programs, with coordinator support, has considerable potential to improve adherence to current guidelines, pending the acquisition and publication of data from ongoing studies of chemoprophylaxis and surveillance in the management of Barrett's oesophagus. In consequence, although there is a paucity of data providing unequivocal demonstration of benefit, there is no proof that surveillance is ineffective. It is, therefore, appropriate to offer surveillance for Barrett's oesophagus in accordance with locally-applicable published guidelines after a full informed discussion of the risks and benefits of surveillance and therapy; continued participation should be reviewed regularly to accommodate changes in the patient's health and expectations.

Blinded comparison of esophageal capsule endoscopy versus conventional endoscopy for a diagnosis of Barrett's esophagus in patients with chronic gastroesophageal reflux

BACKGROUND

Esophageal capsule endoscopy (ECE) is an alternative to EGD for Barrett's esophagus screening. A multicenter study found ECE to be safe, well tolerated, and accurate; however, a post hoc adjudication process was used that may have biased results.

OBJECTIVE

To assess the accuracy of ECE for the diagnosis of Barrett's esophagus.

DESIGN

Prospective and blinded, with no adjudication.

PATIENTS

Screening patients with chronic gastroesophageal reflux and surveillance patients with known Barrett's esophagus.

INTERVENTIONS

ECE followed by EGD in each subject.

MAIN OUTCOME MEASUREMENTS

Sensitivity, specificity, and positive and negative predictive values of ECE for Barrett's esophagus by using EGD results, with histologic confirmation as the criterion standard.

RESULTS

Ninety-six subjects were enrolled, of whom 90 (94%) completed the study, including 66 screening and 24 surveillance patients. ECE was 67% sensitive and 84% specific for identifying Barrett's esophagus, diagnosing 14 of 21 cases of biopsy-confirmed Barrett's esophagus. Positive and negative predictive values were 22% and 98%, respectively (calculated for screening patients only). Sensitivity for short- and long-segment Barrett's esophagus was similar.

CONCLUSIONS

Our blinded, unadjudicated study shows that ECE had only moderate sensitivity and specificity for identifying Barrett's esophagus. ECE in its present form is not suitable as a primary screening tool for Barrett's esophagus but may be used in patients unwilling to undergo EGD. Inadequate visualization of the gastroesophageal junction may be the cause of suboptimal ECE accuracy; this may be improved by advances in ingestion protocol and capsule calibration.

Endoscopic therapy of dysplasia and early-stage cancers of the esophagus

Endoscopic treatments have become a viable alternative for some patients with early-stage esophageal neoplasia. Although esophagectomy remains the standard of care for high-grade dysplasia and superficial cancers, surgical morbidity and mortality may deter patients who are medically unfit or reluctant to undergo surgery. Photodynamic therapy (PDT) and endoscopic mucosal resection (EMR) are the best-studied nonsurgical approaches at present. PDT has been reported to eradicate high-grade dysplasia (HGD) and early Barrett's cancers at rates ranging from 75% to 100% and 17% to 100%, respectively, and a recent randomized controlled trial confirmed that PDT may prevent progression of HGD to cancer. Complete remission rates greater than 90% have also been reported with EMR and other mucosa-ablating interventions, although recurrence rates necessitate close endoscopic surveillance and retreatment in some patients. In addition to PDT and EMR, several emerging endoscopic treatment options for superficial esophageal neoplasia may provide attractive alternatives to surgery.

Cost utility of screening for Barrett's esophagus with esophageal capsule endoscopy versus conventional upper endoscopy

BACKGROUND & AIMS

Screening for Barrett's esophagus with conventional esophagoduodenoscopy (EGD) is recommended to decrease mortality from esophageal adenocarcinoma. Esophageal capsule endoscopy (ECE) has recently been shown to be accurate in detecting Barrett's esophagus. We aimed to compare the cost-effectiveness of screening by ECE with screening by EGD.

METHODS

A Markov model of 50-year-old white men with symptoms of gastroesophageal reflux was constructed to compare screening modalities. The model incorporated direct medical costs and indirect costs of lost productivity and followed the patients until age 80 years or death. Outcomes were analyzed from the societal perspective.

RESULTS

EGD screening prevented 60% of cancer deaths at a cost of $11,254 per quality-adjusted life year gained compared with no screening. ECE prevented 53% of cancer deaths and provided 9 fewer quality-adjusted days at greater cost than EGD. If society were only willing to pay $50,000 per quality-adjusted life year gained, then capsule screening would be preferred if the income of the patient and driver were each greater than $280,682. Otherwise, the findings were robust to all sensitivity analyses.

CONCLUSIONS

Screening for Barrett's esophagus with either EGD or ECE results in similar outcomes, but EGD is the preferred strategy. Both strategies appear cost-effective, and the model does not take into account patient preferences for screening modality or adherence.

Identifying intestinal metaplasia at the squamocolumnar junction by using optical coherence tomography

BACKGROUND

Optical coherence tomography (OCT) is an optical imaging method that produces high-resolution cross-sectional images of the esophagus. The accuracy of OCT for differentiating tissue types at the squamocolumnar junction (SCJ) has not been established.

OBJECTIVE

The purpose of this study was to identify and validate OCT image criteria for distinguishing metaplastic from nonmetaplastic tissue at the SCJ.

DESIGN

A total of 196 biopsy-correlated OCT images of the SCJ were acquired from 113 patients undergoing upper endoscopy. A pathologist blinded to the OCT results reviewed each pathology specimen and determined the presence of the following histopathology: gastric cardia, squamous mucosa, pancreatic metaplasia, and intestinal metaplasia. An algorithm for diagnosing specialized intestinal metaplasia (SIM) was created by reviewing a training set of 40 biopsy-correlated OCT images. Two blinded investigators prospectively tested the algorithm on a validation set of 123 images.

RESULTS

OCT images of squamous mucosa were characterized by a layered appearance without epithelial glands; gastric cardia, by vertical pit and gland structure, a well-defined epithelial surface reflectivity, and relatively poor image penetration; and SIM by an irregular architecture and good image penetration. The OCT criteria were 85% sensitive and 95% specific for SIM when applied retrospectively to the training set. When applied to the validation set, the algorithm was 81% sensitive for both OCT readers and 66% and 57% specific for diagnosing SIM. The interobserver agreement was good (kappa = 0.53).

CONCLUSIONS

OCT imaging can identify SIM at the SCJ with an accuracy similar to that of endoscopy.

Barrett's oesophagus: an audit of surveillance over a 17-year period

OBJECTIVE

To audit whether our patients with Barrett's oesophagus (BO) enter into our endoscopic surveillance programme and whether they continue with it after entry. We have determined the incidence of oesophageal adenocarcinoma among our surveyed patients.

DESIGN

We retrospectively audited prospectively collected data from our BO surveillance programme over the years 1987-2003.

SETTING

An inner city teaching hospital.

RESULTS

During these years, 466 patients with BO were diagnosed (392 long segment, >or=3 cm), 29 had oesophageal adenocarcinoma at diagnosis, 232 [195 with intestinal metaplasia (IM) on biopsy] had at least one follow-up endoscopy, and 205 have not been re-endoscoped. In 27 out of 205 no IM was present. Of the remaining 178 out of 205 with IM, 30 were within 2 years of diagnosis and 148 have not been re-endoscoped for the following reasons: age (51), non-attendance (35), not referred back by general practitioner (30), non-oesophageal cancer (14), severe concurrent illness (12), death (three), refused follow-up (two), left the area (one). The 195 patients with IM who entered endoscopic surveillance consisted of 108 men and 87 women (aged 62.9 years, range 31-96), were followed for a total of 1068 patient-years (average 5.5 years), and had 556 endoscopies (average 2.9 per patient). Ninety-seven out of 195 patients remain under active endoscopic surveillance but 98 discontinued for the following reasons: age (31), non attendance (21), death (21 including one from oesophageal adenocarcinoma), refused follow up (seven), concurrent illness (six), left the area (four), no IM on repeat biopsies (three). Of the 195 patients with IM, four developed low-grade dysplasia, two high-grade dysplasia and four adenocarcinoma (incidence 0.37%); 178 out of 195 have been maintained on proton pump inhibitor (PPI) therapy.

CONCLUSIONS

The majority of patients with BO either do not enter or do not continue in an endoscopic surveillance programme. This needs to be acknowledged when the workload and cost of BO surveillance programmes are considered. The incidence of adenocarcinoma was low compared with many published series, and we speculate whether this is the result of maintenance PPI therapy.

Defining a clinically significant adverse impact of diagnosing Barrett's esophagus

BACKGROUND

Diagnosing a potentially life-threatening disease may adversely affect patient quality of life (QOL) independent of biologic effects. It is unknown whether the mere diagnosis of Barrett's esophagus (BE) adversely impacts patients' preferences (health-state utility) sufficiently to impair the cost-effectiveness of endoscopic screening for esophageal adenocarcinoma.

GOAL

To calculate the threshold impact on utility incurred by diagnosing BE that would allow screening to remain cost-effective.

STUDY

A Markov model was developed to examine strategies of no screening, and screening with surveillance of BE. Patients were 50-year-old white men with symptoms of gastroesophageal reflux followed until 80 years of age or death. The primary outcomes were the threshold decrements in utility incurred by diagnosing BE based on willingness to pay (WTP) of dollar 50,000 and dollar 100,000 per quality-adjusted life-year (QALY) gained.

RESULTS

For a WTP of dollar 50,000/QALY, the decrement in utility could be as great as 9%, meaning that screening is cost-effective as long as diagnosing BE does not impair QOL by more than 9%. For a WTP of dollar 100,000, the decrement could be as great as 10.5%.

CONCLUSIONS

The decrement in utility caused by diagnosing BE may be substantial without compromising the cost-effectiveness of endoscopic screening.

The rationale for screening and surveillance of Barrett's metaplasia

Oesophageal adenocarcinoma is a rare cancer; however, it is the most rapidly increasing cancer in the western world. Barrett's oesophagus is the only recognised precursor and is associated with the majority of cases of adenocarcinoma. The role of screening and surveillance in patients with Barrett's oesophagus remains controversial. There is insufficient evidence to show that screening improves survival and is cost-effective. Indirect evidence suggests that patients diagnosed with cancer while undergoing surveillance endoscopy are diagnosed at an earlier stage and have an improved survival. The problems with current surveillance techniques include lack of data on natural history of Barrett's oesophagus, test invasiveness, costs, lack of standardisation and validation of biopsy and treatment protocols, and endoscopy intervals. The use of novel endoscopic techniques and biomarkers combined with better identification of high-risk groups could make screening and surveillance a cost-effective practice in the future.

Barrett’s Esophagus: Diagnostic Approaches and Surveillance

In an effort to identify those patients at risk for developing esophageal adenocarcinoma, the American College of Gastroenterology recommends screening endoscopy in patients with chronic gastroesophageal reflux disease. Surveillance endoscopy is recommended every 3 years in those patients without dysplasia. For those patients with verified low-grade dysplasia, yearly surveillance endoscopy is recommended. In the case of high-grade dysplasia (HGD), either intensive endoscopic surveillance (focal HGD) or ablation/resection can be performed (multifocal HGD). Both observational and cost-effectiveness analyses suggest a potential benefit of endoscopic screening and surveillance, though these findings remain to be validated in controlled clinical trials. The development of new endoscopic imaging modalities may enhance the yield of biopsies obtained during screening and surveillance regimens.

Does screening for Barrett's esophagus and adenocarcinoma of the esophagus prolong survival?

Despite the paucity of data supporting its use, screening upper endoscopy for patients with chronic gastroesophageal reflux disease symptoms to assess for Barrett's esophagus and esophageal adenocarcinoma has become a widely accepted practice. We apply the principles of screening to Barrett's esophagus and esophageal adenocarcinoma. Critical application of the key criteria of screening to this situation demonstrates that several criteria are unfulfilled. Key data are not available with which to judge other criteria. The major fault with screening for Barrett's esophagus is that the at-risk population is too broadly characterized and that too many cancers occur outside of this risk pool. Thus, recommendations for screening cannot be endorsed. Efforts may be better directed at further research identifying groups at risk for esophageal adenocarcinoma, developing more accurate and less-invasive methods of diagnosis, and discovering the underlying factors which continue to drive the increased incidence of this disease.

The cost-effectiveness of biomarkers for predicting the development of oesophageal adenocarcinoma

BACKGROUND

The recommended surveillance strategy for oesophageal adenocarcinoma may prevent as few as 50% of cancer deaths. Tissue biomarkers have been proposed to identify high-risk patients.

AIM

To determine performance characteristics of an ideal biomarker, or panel of biomarkers, that would make its use more cost-effective than the current surveillance strategy.

METHODS

We created a Markov model using data from published literature, and performed a cost-utility analysis. The population consisted of 50-year-old Caucasian men with gastro-oesophageal reflux, who were monitored until age 80. We examined strategies of observation only, current practice (dysplasia-guided surveillance), surveillance every 3 months for patients with a positive biomarker (biomarker-guided surveillance), and oesophagectomy immediately for a positive biomarker (biomarker-guided oesophagectomy). The primary outcome was the threshold cost and performance characteristics needed for a biomarker to be more cost-effective than current practice.

RESULTS

Regardless of the cost, the biomarker needs to be at least 95% specific for biomarker-guided oesophagectomy to be cost-effective. For biomarker-guided surveillance to be cost-effective, a $100 biomarker could be 80% sensitive and specific.

CONCLUSIONS

Biomarkers predicting the development of oesophageal adenocarcinoma would need to be fairly accurate and inexpensive to be cost-effective. These results should guide the development of biomarkers for oesophageal adenocarcinoma.

Review article: anti-reflux surgery and endoluminal therapies

In the short term, fundoplication and antisecretory medication are equally effective in the management of gastro-oesophageal reflux disease. However, over the long term, the fundoplication wrap tends to become loose, and many surgical patients continue to take antisecretory medication after surgery. The operation is technically complex and takes a long time to learn. Inexperience of the individual surgeon is a major factor contributing to the occurrence of postsurgical complications. Fundoplication does not prevent the occurrence of Barrett's oesophagus nor its progression to oesophageal adenocarcinoma. There is no evidence to suggest that the procedure is less costly or more cost-effective than long-term maintenance therapy with antisecretory medications, especially if surgical failures and postsurgical complications are taken into account. Fundoplication represents an alternative to medical therapy in patients with gastro-oesophageal reflux disease who cannot or do not want to be on long-term maintenance therapy with antisecretory medication. Endoluminal procedures, such as radiofrequency ablation, endoscopic suturing and injection at the gastro-oesophageal junction, work only in mild forms of reflux disease. They fail to provide complete relief of reflux symptoms and do not heal erosive oesophagitis. All endoluminal procedures would have to undergo major technological improvements before they could become comparable with fundoplication or antisecretory therapy.

A critical review of the diagnosis and management of Barrett's esophagus: the AGA Chicago Workshop

BACKGROUND & AIMS

The diagnosis and management of Barrett's esophagus (BE) are controversial. We conducted a critical review of the literature in BE to provide guidance on clinically relevant issues.

METHODS

A multidisciplinary group of 18 participants evaluated the strength and the grade of evidence for 42 statements pertaining to the diagnosis, screening, surveillance, and treatment of BE. Each member anonymously voted to accept or reject statements based on the strength of evidence and his own expert opinion.

RESULTS

There was strong consensus on most statements for acceptance or rejection. Members rejected statements that screening for BE has been shown to improve mortality from adenocarcinoma or to be cost-effective. Contrary to published clinical guidelines, they did not feel that screening should be recommended for adults over age 50, regardless of age or duration of heartburn. Members were divided on whether surveillance prolongs survival, although the majority agreed that it detects curable neoplasia and can be cost-effective in selected patients. The majority did not feel that acid-reduction therapy reduces the risk of esophageal adenocarcinoma but did agree that nonsteroidal antiinflammatory drugs are associated with a cancer risk reduction and are of promising (but unproven) value. Participants rejected the notion that mucosal ablation with acid suppression prevents adenocarcinoma in BE but agreed that this may be an appropriate strategy in a subgroup of patients with high-grade dysplasia.

CONCLUSIONS

Based on this review of BE, the opinions of workshop members on issues pertaining to screening and surveillance are at variance with published clinical guidelines.

Serological testing for coeliac disease in patients with symptoms of irritable bowel syndrome: a cost-effectiveness analysis

BACKGROUND

Patients diagnosed with irritable bowel syndrome may have coeliac disease.

AIM

To evaluate the cost-effectiveness of coeliac disease testing in suspected irritable bowel syndrome.

METHODS

We used decision analysis to estimate the number of coeliac disease cases detected, quality-adjusted life-years gained, and costs resulting from testing suspected irritable bowel syndrome patients for tissue transglutaminase antibody or an antibody panel (tissue transglutaminase, gliadin, total immunoglobulin A). Positive tests prompted endoscopic biopsy. A gluten-free diet improved quality of life in coeliac disease.

RESULTS

Assuming a coeliac disease prevalence of 3%, tissue transglutaminase detected 28 and the panel detected 29 of 30 coeliac disease cases among 1000 suspected irritable bowel syndrome patients. The cost/case detected was $4600 with tissue transglutaminase and $8800 with the panel. The cost/quality-adjusted life-year gained with tissue transglutaminase was $7400, and the incremental cost/quality-adjusted life-year gained for the panel vs. tissue transglutaminase was $287 000. Tissue transglutaminase cost under $100 000/quality-adjusted life-year gained at a coeliac disease prevalence >/=1.1%, assuming a modest utility gain of 0.005 with coeliac disease diagnosis.

CONCLUSIONS

Testing for coeliac disease in patients with suspected irritable bowel syndrome is likely to be cost-effective even at a relatively low coeliac disease prevalence and with small improvements in quality of life with a gluten-free diet.

Cost-effectiveness of aspirin chemoprevention for Barrett's esophagus

BACKGROUND

Recent data suggest that nonsteroidal anti-inflammatory drugs, including aspirin, may prevent the progression of Barrett's esophagus to adenocarcinoma. However, use of aspirin is associated with numerous potential complications, including gastrointestinal bleeding and hemorrhagic strokes. We used a modeling approach to determine and compare the effectiveness and cost-effectiveness of aspirin with and without endoscopic surveillance to prevent esophageal adenocarcinoma.

METHODS

A Markov Monte Carlo decision model was constructed to compare four strategies for management of Barrett's esophagus: aspirin therapy, endoscopic surveillance with biopsies, both, or neither. Patients who took a daily enteric-coated aspirin were modeled to have a 50% reduction in the incidence of esophageal adenocarcinoma but could have complications related to therapy, at which point the aspirin was discontinued. Potential cardiac benefits of aspirin and its role in the chemoprevention of other cancers were not included in the analysis. The analysis was from a societal perspective from age 55 years until death. Sensitivity analyses were performed to investigate the effects of changes in model parameters on estimated costs and effectiveness outcomes across a wide range of assumptions.

RESULTS

Aspirin therapy was more effective and less costly than no therapy, resulting in 0.19 more quality-adjusted life years (QALYs). The combination of aspirin and endoscopic surveillance produced 0.27 more QALYs than no therapy at a cost of 13,400 U.S. dollars more, for an associated incremental cost-effectiveness ratio of 49,600 U.S. dollars/QALY. Aspirin use in combination with endoscopic surveillance dominated endoscopic surveillance alone, resulting in 0.06 more QALYs and 11,400 U.S. dollars less cost. The model's results were sensitive to increasing age and to decreased benefit or delay in aspirin's chemopreventive efficacy.

CONCLUSION

Using published values of parameters, regardless of whether a patient undergoes endoscopic surveillance, aspirin use in the management of Barrett's esophagus appears to be a cost-effective strategy to prevent esophageal adenocarcinoma.

Review article: screening and surveillance of Barrett's oesophagus: what is a cost-effective framework?

There is a strong association between symptomatic gastro-oesophageal reflux and oesophageal adenocarcinoma. With this in mind, the American College of Gastroenterology has recently revised its practice guidelines for the screening of patients with chronic gastro-oesophageal reflux disease (GERD) to identify those at risk of oesophageal adenocarcinoma, and recommends surveillance to identify curable oesophageal neoplasms in patients with established Barrett's oesophagus. Patients with chronic GERD symptoms, particularly those aged over 50 years, should undergo upper endoscopy. Patients found to have Barrett's oesophagus should be treated with acid suppression for GERD symptoms and then undergo regular surveillance endoscopy. Surveillance endoscopy every 3 years is recommended for those without dysplasia. For patients with verified low-grade dysplasia, yearly surveillance endoscopy is recommended. For those with focal high-grade dysplasia (defined as high-grade dysplastic changes involving fewer than five crypts), the condition may be followed with endoscopic surveillance performed at 3-month intervals. If there is verified, multifocal high-grade dysplasia, intervention (e.g. oesophagectomy) may be considered. Both observational and computer models suggest a benefit associated with screening and surveillance. Endoscopic screening and surveillance for Barrett's oesophagus compares favourably with mammography for the detection of breast cancer and other accepted medical practices.

A prospective, blinded study of diagnostic esophagoscopy with a superthin, stand-alone, battery-powered esophagoscope

OBJECTIVES

A more widely available, well-tolerated, and cost-effective technique is needed to screen a broad population at risk for esophageal cancer. An ideal solution might be to perform unsedated esophagoscopy with an entirely self-contained, small-caliber endoscope. In a prospective, blinded study in three phases, we compared the feasibility, patient tolerance, and diagnostic accuracy of esophagoscopy performed with a prototype, superthin, battery-powered esophagoscope (BPE) with standard video esophagogastroduodenoscopy (SVE).

METHODS

In phase I, 10 healthy volunteers underwent both peroral and transnasal esophagoscopy with BPE to evaluate the technical feasibility of the examination. For phases II and III, patients were recruited to have BPE before SVE. In phase II, both procedures were performed with conscious sedation. In phase III, the BPE was performed with only topical anesthesia. Two endoscopists assessed the technical performance of the endoscope and patient tolerance and recorded the esophageal findings independently.

RESULTS

In phase I, all endoscopists reported adequate visualization of the esophagus in the 10 volunteers. A total of 181 patients were evaluated in phases II and III (89 in phase II, 92 in phase III). The sensitivity for detecting columnar lined esophagus was 94% in phase II and 95% in phase III. The sensitivity for all esophageal findings was 87% and 86% in phases II and III, respectively. The technical performance of the endoscope was significantly worse for BPE compared with the SVE. The patient tolerance as evaluated by the endoscopist was similar for both procedures. Ninety-five percent of the patients undergoing unsedated BPE were willing to have the procedure repeated under similar circumstances.

CONCLUSIONS

Unsedated esophagoscopy with a 3.1-mm, battery-powered, stand-alone esophagoscope is feasible, well tolerated, and accurate in detecting esophageal pathologies. It might be an efficient and cost-effective screening tool for the detection of columnar lined esophagus.

Clinical Manifestations and Esophageal Complications of GERD

This report focuses on the manifestations of gastroesophageal reflux disease (GERD) that are caused directly by contact between refluxed gastric juice and the esophageal mucosa. These manifestations include heartburn, peptic esophageal erosion and ulceration, peptic esophageal stricture, and Barrett esophagus. Peptic esophageal erosions and ulcerations are excavated defects in the esophageal mucosa that result when epithelial cells succumb to the caustic effects of refluxed acid and pepsin. Uncommonly, esophageal ulcers are complicated by hemorrhage, perforation, and penetration into the airway. Esophageal ulcers can stimulate fibrous tissue production and collagen deposition that result in stricture formation, and the ulcers can heal through a metaplastic process in which an intestinal-type epithelium replaces the damaged squamous cells (Barrett esophagus). The management of these conditions is discussed below.

Living with chronic heartburn: insights into its debilitating effects

Heartburn is a common, often disabling condition. Twenty percent of adults exhibit symptoms at least once weekly. Few obtain complete satisfactory relief of their symptoms without the simultaneous implementation of significant lifestyle modifications and appropriate pharmacologic intervention. Poor sleep and chronic symptoms impair the QoL in 25% to 30% of such cases. Nocturnal symptoms are more troublesome, more difficult to treat, and are often manifested by extraesophageal symptoms. Several patients, however, unknown to their physicians continue to experience heartburn, despite lifestyle changes and taking prescription drugs. Adequate acid suppression is currently essential to effective management of the condition.

Barrett's oesophagus: optimal strategies for prevention and treatment

Barrett's oesophagus is a change in the lining of the distal oesophagus recognised at endoscopy and documented to have intestinal metaplasia by biopsy. It is thought that it is an acquired condition resulting from chronic gastro-oesophageal reflux disease (GORD). Barrett's oesophagus has the potential to progress to adenocarcinoma of the oesophagus. Evidence to support the association between Barrett's oesophagus and GORD appears to be strong but circumstantial. The intermediate steps that lead from GORD to Barrett's oesophagus are speculative and the timeline for the development of this condition remains obscure. It has yet to be demonstrated that erosive oesophagitis is a necessary intermediate step for the development of Barrett's oesophagus. In spite of effective therapy, documentation that medical or surgical therapy prevents Barrett's oesophagus is lacking. The goal of screening for Barrett's oesophagus is ultimately to improve the survival of patients with adenocarcinoma of the oesophagus. This goal has not been achieved and the evidence-based criteria for screening remain to be defined. Medical and surgical therapy of Barrett's oesophagus is effective in controlling reflux, although not proven to prevent neoplastic progression of the at risk mucosa. Endoscopic techniques of mucosal injury have been applied as alternatives to oesophagectomy in efforts to prevent progression to cancer. Surveillance endoscopy and biopsy is the currently accepted method aimed at early intervention and improved survival for oesophageal adenocarcinoma. A working surveillance protocol to accomplish this is proposed based on dysplasia grade. If no dysplasia is found and confirmed with subsequent endoscopy and biopsy, a 3-year interval is recommended. If only low grade dysplasia is confirmed, then annual endoscopy until no dysplasia is recognised is recommended. On the basis of defined risk factors, high grade dysplasia can lead to intense surveillance every 3 months or an intervention. Future developments in understanding the biology of Barrett's oesophagus and in therapeutic interventions will provide an opportunity for more effective screening, surveillance and prevention of neoplastic progression.

Review article: test and treat or treat and test in reflux disease?

The role of diagnostic testing in reflux disease is in evolution. There is little question that patients with dysphagia, bleeding or other 'alarm' symptoms, should undergo early endoscopy. A substantial proportion of patients presenting with reflux symptoms have endoscopy negative reflux disease. pH testing is both inconvenient and lacks the sensitivity and specificity required for a 'gold standard'. Empirical trials of therapy using proton pump inhibitors have shown that a trial of treatment may be the most accurate way of diagnosing gastro-oesophageal reflux disease (GERD) and may the optimal strategy from a cost-effectiveness standpoint. On the other hand, the increasing rate of oesophageal adenocarcinoma has raised questions about the possible value of screening endoscopy to determine if Barrett's oesophagus is present. The role of endoscopic testing in the average patient is therefore shifting from a diagnostic modality to one that helps manage risk by identifying Barrett's oesophagus.

A case-control study of endoscopy and mortality from adenocarcinoma of the esophagus or gastric cardia in persons with GERD

BACKGROUND

This study assessed whether EGD reduces mortality from adenocarcinoma of the esophagus or gastric cardia for patients with gastroesophageal reflux.

METHODS

A case-control study was performed. A total of 245 incident cases of death caused by adenocarcinoma of the esophagus or gastric cardia (1995-1999) in which reflux was present were identified using Veterans Health Administration databases. A total of 980 controls with reflux but no death from adenocarcinoma were frequency matched for age, gender, and race. The occurrences of EGD from 1990 onward were compared for cases and controls. Logistic regression analysis with adjustment for potential confounding factors was performed.

RESULTS

All the subjects were men. Cases were significantly less likely to have had an EGD in the time period of interest as compared with controls (adjusted odds ratio 0.66: 95% CI [0.45, 0.96], p = 0.03). This negative association was as strong for any EGD performed within 1 to 8 years before diagnosis as for a more recent EGD. However, there were no controls that included esophagectomy and no controls with a nonfatal diagnosis of adenocarcinoma, raising the question of whether EGD and reduced mortality are causally linked. The risk of dying from adenocarcinoma was significantly lower for men with a diagnosis of GERD as an inpatient relative to men in whom the diagnosis was made as an outpatient (adjusted odds ratio 0.21: 95% CI [0.15, 0.31], p < 0.01).

CONCLUSIONS

For patients with GERD, performing an EGD is associated with reduced mortality from adenocarcinoma of the esophagus or gastric cardia, but whether this is a causative association remains unclear.