Conclusions from the histological diagnosis of low-grade intraepithelial neoplasia in Barrett's oesophagus

High Proportions of Newly Detected Visible Lesions and Pathology Grade Change Among Patients with Barrett's Esophagus Referred to Expert Centers

BACKGROUND AND AIMS

Endoscopic eradication therapy for Barrett's esophagus (BE)-related neoplasia is increasingly being performed at tertiary and community centers. While it has been suggested that these patients should be evaluated at expert centers, the impact of this practice has not been evaluated. We aimed to assess the impact of referral of BE-related neoplasia patients to expert centers by assessing the proportion of patients with change in pathological diagnosis and visible lesions detected.

METHODS

Multiple databases were searched until December 2021 for studies of patients with BE referred from the community to expert center. The proportions of pathology grade change and newly detected visible lesions at expert centers were pooled using a random-effects model. Subgroup analyses were performed based on baseline histology and other relevant factors.

RESULTS

Twelve studies were included (1630 patients). The pooled proportion of pathology grade change after expert pathologist review was 47% (95% CI 34-59%) overall and 46% (95% CI 31-62%) among patients with baseline low-grade dysplasia. When upper endoscopy was repeated at an expert center, the pooled proportion of pathology grade change was still high 47% (95% 26-69%) overall and 40% (95% CI 34-45%) among patients with baseline LGD. The pooled proportion of newly detected visible lesions was 45% (95% CI 28-63%) and among patients referred with LGD was 27% (95% CI 22-32%).

CONCLUSION

An alarmingly high proportion of newly detected visible lesions and pathology grade change were found when patients were referred to expert centers supporting the need for centralized care for BE-related neoplasia patients.

Risk of progression in Barrett's esophagus based on diagnoses of general and gastrointestinal pathologists. A retrospective case-control study from Northern and Central Finland

BACKGROUND

Esophageal adenocarcinoma (EAC) is the sixth leading cause of cancer-related death worldwide. It develops through Barrett's metaplasia - dysplasia sequence. However, the effectiveness of endoscopic surveillance is limited, since diagnosis of low-grade dysplasia (LGD) is known to be challenging for pathologists. Our aim was to compare the risk of Barrett's progression based on diagnoses of general and expert gastrointestinal (GI) pathologists in a population-based cohort.

METHODS

A total of 60 patients with non-dysplastic metaplasia (BE) or LGD progressing to high grade dysplasia (HGD) or EAC during follow-up could be identified in the population. For comparison, series representing non-progressive BE (n = 56) and LGD cases (n = 54), matched for age, gender, and length of follow-up were collected. All available original HE stained slides (n = 292) were blindly re-evaluated by two experienced GI pathologists and patient groups of progressive non-progressive BE and LGD were formed according to revised diagnoses.

RESULTS

Original diagnosis for each sample was changed in 25% of BE, 59% of LGD, and 33% of HGD diagnoses. Of the original LGD diagnoses, 53% were downgraded to BE or indefinite for dysplasia (ID). Of LGD diagnoses made by an expert GI pathologist, 61% were in the progressive LGD group, whereas only 42% of general pathologists' LGD diagnoses were in the progressive LGD group.

CONCLUSION

Based on this retrospective case-control study, LGD is strongly over-diagnosed among general pathologists. LGD diagnosed by expert GI pathologists predicts progressive disease. Recommendation for consensus diagnosis by expert GI pathologists is justified also in the Finnish population-based setting.

Optimizing Outcomes with Radiofrequency Ablation of Barrett's Esophagus: Candidates, Efficacy and Durability

The treatment of early Barrett's esophagus (BE) has undergone a paradigm shift from surgical subtotal esophagectomy to organ-saving endoluminal treatment. Over the past 15 years, several high-quality studies were conducted to assess safe oncological outcome of endoscopic resection of mucosal adenocarcinoma and high-grade dysplasia. It became clear that add-on ablative therapy with radiofrequency ablation (RFA) significantly reduces recurrence risk of neoplasia after resection. In this review, we highlight the most essential elements to optimize outcomes of RFA of BE, addressing the correct indication and patient selection in combination with the most efficient and safest treatment protocols to obtain long-term durability.

Histopathologist features predictive of diagnostic concordance at expert level among a large international sample of pathologists diagnosing Barrett's dysplasia using digital pathology

OBJECTIVE

Guidelines mandate expert pathology review of Barrett's oesophagus (BO) biopsies that reveal dysplasia, but there are no evidence-based standards to corroborate expert reviewer status. We investigated BO concordance rates and pathologist features predictive of diagnostic discordance.

DESIGN

Pathologists (n=51) from over 20 countries assessed 55 digitised BO biopsies from across the diagnostic spectrum, before and after viewing matched p53 labelling. Extensive demographic and clinical experience data were obtained via online questionnaire. Reference diagnoses were obtained from a review panel (n=4) of experienced Barrett's pathologists.

RESULTS

We recorded over 6000 case diagnoses with matched demographic data. Of 2805 H&E diagnoses, we found excellent concordance (>70%) for non-dysplastic BO and high-grade dysplasia, and intermediate concordance for low-grade dysplasia (42%) and indefinite for dysplasia (23%). Major diagnostic errors were found in 248 diagnoses (8.8%), which reduced to 232 (8.3%) after viewing p53 labelled slides. Demographic variables correlating with diagnostic proficiency were analysed in multivariate analysis, which revealed that at least 5 years of professional experience was protective against major diagnostic error for H&E slide review (OR 0.48, 95% CI 0.31 to 0.74). Working in a non-teaching hospital was associated with increased odds of major diagnostic error (OR 1.76, 95% CI 1.15 to 2.69); however, this was neutralised when pathologists viewed p53 labelled slides. Notably, neither case volume nor self-identifying as an expert predicted diagnostic proficiency. Extrapolating our data to real-world case prevalence suggests that 92.3% of major diagnostic errors are due to overinterpreting non-dysplastic BO.

CONCLUSION

Our data provide evidence-based criteria for diagnostic proficiency in Barrett's histopathology.

Proton Pump Inhibitors and Radiofrequency Ablation for Treatment of Barrett's Esophagus

Gastroesophageal Reflux Disease (GERD) is characterized by acid and bile reflux in the distal oesophagus, and this may cause the development of reflux esophagitis and Barrett's oesophagus (BE). The natural histological course of untreated BE is non-dysplastic or benign BE (ND), then lowgrade (LGD) and High-Grade Dysplastic (HGD) BE, with the expected increase in malignancy transfer to oesophagal adenocarcinoma (EAC). The gold standard for BE diagnostics involves high-resolution white-light endoscopy, followed by uniform endoscopy findings description (Prague classification) with biopsy performance according to Seattle protocol. The medical treatment of GERD and BE includes the use of proton pump inhibitors (PPIs) regarding symptoms control. It is noteworthy that long-term use of PPIs increases gastrin level, which can contribute to transfer from BE to EAC, as a result of its effects on the proliferation of BE epithelium. Endoscopy treatment includes a wide range of resection and ablative techniques, such as radio-frequency ablation (RFA), often concomitantly used in everyday endoscopy practice (multimodal therapy). RFA promotes mucosal necrosis of treated oesophagal region via high-frequency energy. Laparoscopic surgery, partial or total fundoplication, is reserved for PPIs and endoscopy indolent patients or in those with progressive disease. This review aims to explain distinct effects of PPIs and RFA modalities, illuminate certain aspects of molecular mechanisms involved, as well as the effects of their concomitant use regarding the treatment of BE and prevention of its transfer to EAC.

Substantial Interobserver Agreement in the Diagnosis of Dysplasia in Barrett Esophagus Upon Review of a Patient's Entire Set of Biopsies

The pathologic diagnosis of dysplasia in Barrett esophagus (BE) suffers from interobserver disagreement. Many of the studies demonstrating disagreement in the diagnosis of dysplasia have pathologists review individual biopsy slides in isolation. To more closely mimic daily practice, 3 pathologists reviewed hematoxylin and eosin slides made from 549 individual biopsy jars obtained from 129 unique patients with a diagnosis of BE. Each pathologist reviewed the entirety of a given patient's biopsy material. The grade of dysplasia present in each biopsy jar was given as well as an overall highest grade of dysplasia from the patient's entire set of biopsies. The interobserver agreement in the diagnosis of dysplasia per biopsy jar and per patient's set of biopsies was measured by Fleiss κ statistic for multiple raters. The κ values for each diagnosis was higher in the per patient analysis compared with the per biopsy jar analysis indicating that pathologists are more likely to agree on the overall grade of dysplasia compared with the grade in an individual biopsy jar. In the per patient analysis, the interobserver agreement in the diagnosis of nondysplastic BE and high-grade dysplasia were substantial (κ=0.66; 95% confidence interval [CI], 0.56-0.76 and κ=0.76; 95% CI, 0.66-0.86, respectively). The interobserver agreement in the diagnosis of low-grade dysplasia (LGD) was fair (κ=0.31; 95% CI, 0.21-0.42). When LGD and high-grade dysplasia were collapsed into 1 category of positive for dysplasia, the interobserver agreement in the per patient analysis remained substantial (κ=0.70; 95% CI, 0.60-0.80), suggesting that much of the disagreement in LGD is not due to lack of recognition of dysplastic Barrett's mucosa, but rather the degree of dysplasia. These results indicate that pathologists can reliably distinguish between nondysplastic BE and dysplastic BE when a patient's entire set of biopsies is reviewed as a group. When second opinions are obtained, all available slides from that endoscopic procedure should be sent for review.

Management of Barrett's esophagus with low-grade dysplasia

Barrett's esophagus progresses to esophageal adenocarcinoma in a stepwise histological fashion of no dysplasia, low grade dysplasia, high grade dysplasia and cancer. Hence the progression to cancer from various histological stages is different. Progression to cancer from low grade dysplasia is highly variable in the literature due to high inter-observer variability between pathologists in diagnosing it. Studies have shown the utility of having confirmation of low grade dysplasia by expert pathologists or documenting its persistence on two subsequent endoscopies in order to unify the diagnosis. The treatment of low grade dysplasia is variable. In this article we summarize the diagnosis, evaluation and management of low grade dysplasia in Barrett's Esophagus.

Longitudinal outcomes of radiofrequency ablation versus surveillance endoscopy for Barrett's esophagus with low-grade dysplasia

Radiofrequency ablation of Barrett's esophagus with low-grade dysplasia is recommended in recent American College of Gastroenterology guidelines, with endoscopic surveillance considered a reasonable alternative. Few studies have directly compared outcomes of radiofrequency ablation to surveillance and those that have are limited by short duration of follow-up. This study aims to compare the long-term effectiveness of radiofrequency ablation versus endoscopic surveillance in a large, longitudinal cohort of patients with Barrett's esophagus, and low-grade dysplasia.We conducted a retrospective analysis of patients with confirmed low-grade dysplasia at a single academic medical center from 1991 to 2014. Patients progressing to high-grade dysplasia or esophageal adenocarcinoma within one year of index LGD endoscopy were defined as missed dysplasia and excluded. Risk factors for progression were assessed via Cox proportional hazards model. Comparison of progression risk was conducted using a Kaplan-Meier analysis. Subset analyses were conducted to examine the effect of reintroducing early progressors and excluding patients diagnosed prior to the advent of ablative therapy. Of 173 total patients, 79 (45.7%) underwent radiofrequency ablation while 94 (54.3%) were untreated, with median follow up of 90 months. Seven (8.9%) patients progressed to high-grade dysplasia or adenocarcinoma despite ablation, compared with 14 (14.9%) undergoing surveillance (P = 0.44). This effect was preserved when patients diagnosed prior to the introduction of radiofrequency ablation were excluded (8.9% vs 13%, P = 0.68). Reintroduction of patients progressing within the first year of follow-up resulted in a trend toward significance for ablation versus surveillance (11.1% vs 23.8%, P = 0.053).In conclusion, progression to high-grade dysplasia or adenocarcinoma was not significantly reduced in the radiofrequency ablation cohort when compared to surveillance. Despite recent studies suggesting the superiority of radiofrequency ablation in reducing progression, diligent endoscopic surveillance may provide similar long-term outcomes.

Discordance Among Pathologists in the United States and Europe in Diagnosis of Low-Grade Dysplasia for Patients With Barrett's Esophagus

BACKGROUND & AIMS

There is suboptimal inter-observer agreement, even among expert gastrointestinal pathologists, in the diagnosis of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE). We analyzed histopathologic criteria required for a diagnosis of LGD using the new subcategories of LGD with inflammatory and dysplastic features. We categorized each diagnosis based on the level of confidence and assessed inter-observer agreement among gastrointestinal pathologists from 5 tertiary centers in the United States and Europe.

METHODS

In the first phase of the study, 3 pathologists held a consensus conference at which they discussed the diagnostic criteria for LGD. In the second phase, 79 slides from patients with BE (23 samples of non-dysplastic BE, 22 samples of LGD, and 34 samples of high-grade dysplasia) were identified, randomly assigned to 7 pathologists (4 from the United States and 3 from Europe), and interpreted in a blinded fashion. κ Values were calculated for inter-observer agreement. We performed multinomial logistic regression analysis to assess the weighting of histologic features with the diagnosis.

RESULTS

The overall κ value for diagnosis was 0.43 (95% confidence interval [CI], 0.42-0.48). When categorized based on degree of dysplasia, the κ value was 0.22 (95% CI, 0.11-0.29) for non-dysplastic BE, 0.11 (95% CI, 0.004-0.15) for LGD, and 0.43 (95% CI, 0.36-0.46) for high-grade dysplasia. When all pathologists made a diagnosis with high confidence, the inter-observer agreement was substantial among the US pathologists (κ, 0.63; 95% CI, 0.61-0.66) and European pathologists (κ, 0.80; 95% CI, 0.74-0.97). The κ values for all diagnoses made by European pathologists were higher than those made by US pathologists.

CONCLUSIONS

In an analysis of criteria used in histopathologic diagnosis of LGD, we did not observe improvement in level of agreement among experienced pathologists, even after accounting for inflammation. The level of inter-observer agreement increased with level of pathologist confidence. There was also a difference in reading of histopathology samples of BE tissues between US and European pathologists.

[Barrett's esophagus and carcinoma: Recommendations of the S2k guideline 2014 and the S3 guideline 2015]

In the current S2k guideline for gastroesophageal reflux disease and the new S3 guideline for esophageal cancer, histopathological evaluation of Barrett's esophagus has been revised and supplemented. The histological diagnosis of Barrett's esophagus still requires the proof of a specialized intestinal metaplastic epithelium (columnar epithelium with goblet cells). Barrett mucosa must be classified as negative, unclear/doubtful, and positive concerning the intraepithelial neoplasia (IEN)/dysplasia according to the current WHO guideline. Each IEN should be confirmed by an external second opinion due to poor interobserver variability. The pathological classification is of decisive importance here, since the recommended monitoring intervals are based solely on the ground of proved IEN. Risk factors in endoscopic resection specimens such as depth of infiltration (m1-m4; sm1-sm3; distance in µm); angioinvasion (L, V); grading and lateral/basal resection margin have to be reported. In surgical specimens, the reference of the tumor center to the gastroesophageal junction and in the neoadjuvant situation the tumor regression should be documented.

The importance of a second opinion in the diagnosis of Barrett's esophagus: a "real life" study

BACKGROUND

Barrett's esophagus is a precancerous lesion, and its identification with the early detection of dysplasia is of paramount importance to prevent adenocarcinoma onset. However, there is still debate on the correct pathological identification of Barrett's esophagus (and of associated dysplasia), and most studies have been conducted in an experimental setting.

AIMS

To assess previous uncertain diagnoses of Barrett's (with and without dysplasia) via a second opinion of an expert pathologist in a real life setting.

PATIENTS AND METHODS

Histological sections of 32 suspected Barrett's patients from ten general Pathology units were centralized into one single unit in which an expert pathologist reviewed the slides blindly.

RESULTS

Overall, in 78% of cases there was diagnostic discordance; in particular, in 64% of cases the presence of low grade dysplasia was not confirmed. Of interest, 28% of cases with the original diagnosis were reclassified as non-Barrett's.

CONCLUSIONS

The pathological diagnosis of Barrett's esophagus, especially with regard to the presence of dysplasia, is still misinterpreted, particularly in the setting of general Pathology units. Thus, a second opinion from an experienced pathologist may help in the interpretation of the results and in starting appropriate follow-up programs.

Outcomes of Radiofrequency Ablation for Dysplastic Barrett's Esophagus: A Comprehensive Review

Barrett's esophagus is a condition in which the normal squamous lining of the esophagus has been replaced by columnar epithelium containing intestinal metaplasia induced by recurrent mucosal injury related to gastroesophageal reflux disease. Barrett's esophagus is a premalignant condition that can progress through a dysplasia-carcinoma sequence to esophageal adenocarcinoma. Multiple endoscopic ablative techniques have been developed with the goal of eradicating Barrett's esophagus and preventing neoplastic progression to esophageal adenocarcinoma. For patients with high-grade dysplasia or intramucosal neoplasia, radiofrequency ablation with or without endoscopic resection for visible lesions is currently the most effective and safe treatment available. Recent data demonstrate that, in patients with Barrett's esophagus and low-grade dysplasia confirmed by a second pathologist, ablative therapy results in a statistically significant reduction in progression to high-grade dysplasia and esophageal adenocarcinoma. Treatment of dysplastic Barrett's esophagus with radiofrequency ablation results in complete eradication of both dysplasia and of intestinal metaplasia in a high proportion of patients with a low incidence of adverse events. A high proportion of treated patients maintain the neosquamous epithelium after successful treatment without recurrence of intestinal metaplasia. Following successful endoscopic treatment, endoscopic surveillance should be continued to detect any recurrent intestinal metaplasia and/or dysplasia. This paper reviews all relevant publications on the endoscopic management of Barrett's esophagus using radiofrequency ablation.

Interobserver reproducibility in pathologist interpretation of columnar-lined esophagus

Confirmation of endoscopically suspected esophageal metaplasia (ESEM) requires histology, but confusion in the histological definition of columnar-lined esophagus (CLE) is a longstanding problem. The aim of this study is to evaluate interpathologist variability in the interpretation of CLE. Thirty pathologists were invited to review three ten-case sets of CLE biopsies. In the first set, the cases were provided with descriptive endoscopy only; in the second and the third sets, ESEM extent using Prague criteria was provided. Moreover, participants were required to refer to a diagnostic chart for evaluation of the third set. Agreement was statistically assessed using Randolph's free-marginal multirater kappa. While substantial agreement in recognizing columnar epithelium (K = 0.76) was recorded, the overall concordance in clinico-pathological diagnosis was low (K = 0.38). The overall concordance rate improved from the first (K = 0.27) to the second (K = 0.40) and third step (K = 0.46). Agreement was substantial when diagnosing Barrett's esophagus (BE) with intestinal metaplasia or inlet patch (K = 0.65 and K = 0.89), respectively, in the third step, while major problems in interpretation of CLE were observed when only cardia/cardia-oxyntic atrophic-type epithelium was present (K = 0.05-0.29). In conclusion, precise endoscopic description and the use of a diagnostic chart increased consistency in CLE interpretation of esophageal biopsies. Agreement was substantial for some diagnostic categories (BE with intestinal metaplasia and inlet patch) with a well-defined clinical profile. Interpretation of cases with cardia/cardia-oxyntic atrophic-type epithelium, with or without ESEM, was least consistent, which reflects lack of clarity of definition and results in variable management of this entity.

Inter-Observer Agreement among Pathologists Using Wide-Area Transepithelial Sampling With Computer-Assisted Analysis in Patients With Barrett's Esophagus

OBJECTIVES

The histopathological diagnosis of Barrett's esophagus (BE)-associated dysplasia has poor inter-observer agreement. The wide-area transepithelial sampling (WATS) procedure uses a minimally invasive brush biopsy technique for acquiring wide-area sampling of BE tissue followed by computer-assisted analysis. In this study, our aim was to assess inter-observer agreement among pathologists in the diagnosis of Barrett's-associated dysplasia using the WATS computer-assisted analysis technique.

METHODS

WATS slides with varying degrees of BE dysplasia were randomly selected and distributed to four pathologists. Each pathologist graded the slides as nondysplastic, low-grade dysplasia (LGD), or high-grade dysplasia/esophageal adenocarcinoma (HGD/EAC) and completed a standardized case report form (CRF) for each slide.

RESULTS

In all, 149 BE slides were evaluated in a blinded manner by 4 pathologists. The slides included the following: no dysplasia (n=109), LGD, and HGD/EAC (n=40). The overall mean kappa value for all 3 diagnoses for the 4 observers was calculated at 0.86 (95% confidence interval (CI) 0.75-0.97). The kappa values (95% CI) for HGD/EAC, IND/LGD, and no dysplasia were 0.95 (0.88-0.99), 0.74 (0.61-0.85), and 0.88 (0.81-0.94), respectively.

CONCLUSIONS

The diagnosis of BE and associated dysplasia using the WATS technique has very high inter-observer agreement. This appears to be significantly higher as compared with previously published data using standard histopathology.

Barrett's oesophagus patients with low-grade dysplasia can be accurately risk-stratified after histological review by an expert pathology panel

OBJECTIVE

Reported malignant progression rates for low-grade dysplasia (LGD) in Barrett's oesophagus (BO) vary widely. Expert histological review of LGD is advised, but limited data are available on its clinical value. This retrospective cohort study aimed to determine the value of an expert pathology panel organised in the Dutch Barrett's Advisory Committee (BAC) by investigating the incidence rates of high-grade dysplasia (HGD) and oesophageal adenocarcinoma (OAC) after expert histological review of LGD.

DESIGN

We included all BO cases referred to the BAC for histological review of LGD diagnosed between 2000 and 2011. The diagnosis of the expert panel was related to the histological outcome during endoscopic follow-up. Primary endpoint was development of HGD or OAC.

RESULTS

293 LGD patients (76% men; mean 63 years±11.9) were included. Following histological review, 73% was downstaged to non-dysplastic BO (NDBO) or indefinite for dysplasia (IND). In 27% the initial LGD diagnosis was confirmed. Endoscopic follow-up was performed in 264 patients (90%) with a median follow-up of 39 months (IQR 16-72). For confirmed LGD, the risk of HGD/OAC was 9.1% per patient-year. Patients downstaged to NDBO or IND had a malignant progression risk of 0.6% and 0.9% per patient-year, respectively.

CONCLUSIONS

Confirmed LGD in BO has a markedly increased risk of malignant progression. However, the vast majority of patients with community LGD will be downstaged after expert review and have a low progression risk. Therefore, all BO patients with LGD should undergo expert histological review of the diagnosis for adequate risk stratification.

Incidence of esophageal adenocarcinoma in Barrett's esophagus with low-grade dysplasia: a systematic review and meta-analysis

BACKGROUND

The natural history of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE) is unclear.

OBJECTIVE

We performed a systematic review and meta-analysis of studies that reported the incidence of esophageal adenocarcinoma (EAC) and/or high-grade dysplasia (HGD) among patients with BE with LGD.

DESIGN

Systematic review and meta-analysis of cohort studies.

PATIENTS

Patients with BE-LGD, with mean cohort follow-up ≥ 2 years.

MAIN OUTCOME MEASUREMENTS

Pooled incidence rates with 95% confidence intervals (CI) of EAC and/or BE-HGD.

RESULTS

We identified 24 studies reporting on 2694 patients with BE-LGD, with 119 cases of EAC. Pooled annual incidence rates of EAC alone and EAC and/or HGD in patients with BE-LGD were 0.54% (95% CI, 0.32-0.76; 24 studies) and 1.73% (95% CI, 0.99-2.47; 17 studies). The results were stable across study setting and location and in high-quality studies. Substantial heterogeneity was observed, which could be explained by stratifying based on LGD/BE ratio as a surrogate for quality of pathology; the pooled annual incidence rates of EAC were 0.76% (95% CI, 0.44-1.09; 14 studies) for LGD/BE ratio <0.15 and 0.32% (95% CI, 0.07-0.58; 10 studies) for LGD/BE ratio >0.15. The annual rate of mortality not related to esophageal disease in patients with BE-LGD was 4.7% (95% CI, 3.2-6.2; 4 studies).

LIMITATIONS

Substantial heterogeneity was observed in the overall analysis.

CONCLUSION

The incidence of EAC among patients with BE-LGD is 0.54% annually. The LGD/BE ratio appears to explain the variation observed in the reported incidence of EAC in different cohorts. Conditions not related to esophageal disease are a major cause of mortality in patients with BE-LGD, although additional studies are warranted.

Barrett's: evolving techniques for dysplasia detection and endoscopic resection

Advanced endoscopic imaging techniques have made the early diagnosis of neoplastic lesions in Barrett's esophagus easier. A new chapter in minimal invasive cancer therapy has been opened. Endoscopic treatment of early neoplasia in Barrett's esophagus (high-grade intraepithelial neoplasia and mucosal adenocarcinoma) has become the method of choice in most countries. Long-term results for endoscopic treatment in a large group of patients are now available. These emerging data suggest that endoscopic therapy is safe and highly effective with long-term complete remission rates of more than 94%. All visible lesions should be treated by endoscopic resection for histologic confirmation of the neoplastic lesion rather than by ablative techniques. After successful endoscopic resection of all visible and localizable high-grade intraepithelial neoplasia and mucosal cancer, ablative treatment of the remaining Barrett's epithelium at risk should be performed to reduce the rate of recurrent or metachronous neoplasia.

Biomarkers in Barrett’s esophagus and esophageal adenocarcinoma: Predictors of progression and prognosis

Barrett’s esophagus is a well-known premalignant lesion of the lower esophagus that is characterized by intestinal metaplasia of the squamous epithelium. It is clinically important due to the increased risk (0.5% per annum) of progression to esophageal adenocarcinoma (EA), which has a poor outcome unless diagnosed early. The current clinical management of Barrett’s esophagus is hampered by the lack of accurate predictors of progression. In addition, when patients develop EA, the current staging modalities are limited in stratifying patients into different prognostic groups in order to guide the optimal therapy for an individual patient. Biomarkers have the potential to improve radically the clinical management of patients with Barrett’s esophagus and EA but have not yet entered mainstream clinical practice. This is in contrast to other cancers like breast and prostate for which biomarkers are utilized routinely to inform clinical decisions. This review aims to highlight the most promising predictive and prognostic biomarkers in Barrett’s esophagus and EA and to discuss what is required to move the field forward towards clinical application.

Low-grade dysplasia in Barrett's esophagus: overdiagnosed and underestimated

OBJECTIVES

Published data on the natural history of low-grade dysplasia (LGD) in Barrett's esophagus (BE) are inconsistent and difficult to interpret. We investigated the natural history of LGD in a large community-based cohort of BE patients after reviewing the original histological diagnosis by an expert panel of pathologists.

METHODS

Histopathology reports of all patients diagnosed with LGD between 2000 and 2006 in six non-university hospitals were reviewed by two expert pathologists. This panel diagnosis was subsequently compared with the histological outcome during prospective endoscopic follow-up.

RESULTS

A diagnosis of LGD was made in 147 patients. After pathology review, 85% of the patients were downstaged to non-dysplastic BE (NDBE) or to indefinite for dysplasia. In only 15% of the patients was the initial diagnosis LGD. Endoscopic follow-up was carried out in 83.6% of patients, with a mean follow-up of 51.1 months. For patients with a consensus diagnosis of LGD, the cumulative risk of progressing to high-grade dysplasia or carcinoma (HGD or Ca) was 85.0% in 109.1 months compared with 4.6% in 107.4 months for patients downstaged to NDBE (P<0.0001). The incidence rate of HGD or Ca was 13.4% per patient per year for patients in whom the diagnosis of LGD was confirmed. For patients downstaged to NDBE, the corresponding incidence rate was 0.49%.

CONCLUSIONS

LGD in BE is an overdiagnosed and yet underestimated entity in general practice. Patients diagnosed with LGD should undergo an expert pathology review to purify this group. In case the diagnosis of LGD is confirmed, patients should undergo strict endoscopic follow-up or should be considered for endoscopic ablation therapy.

Routinely diagnosed low-grade dysplasia in Barrett's oesophagus: a population-based study of natural history

AIMS

To examine the natural history of columnar-lined oesophagus with routinely diagnosed low-grade dysplasia and ascertain the risk of oesophageal adenocarcinoma development.

METHODS AND RESULTS

A multicentre retrospective cohort study of 283 patients with low-grade dysplasia. Follow-up data were obtained from examination of hospital records. One hundred and forty-four patients had biopsies prior to low-grade dysplasia diagnosis and 217 had follow-up biopsies after index low-grade dysplasia diagnosis. In these patients the incidence of high-grade dysplasia and adenocarcinoma combined was 4.6% per annum and of adenocarcinoma alone was 2.7% per annum. At most recent follow-up, 43 (19.8%) had persistent low-grade dysplasia, 37 (17.1%) had changes indefinite for dysplasia and 108 (49.8%) had non-dysplastic columnar-lined oesophagus. When prevalent cases were excluded (those occurring within 1 year of index low-grade dysplasia diagnosis), the annual incidence of high-grade dysplasia and adenocarcinoma combined was 2.2% and of adenocarcinoma alone was 1.4%. The relative risk for adenocarcinoma development in low-grade dysplasia compared with non-dysplastic columnar-lined oesophagus was 2.871 (P = 0.002).

CONCLUSIONS

Low-grade dysplasia has a threefold increased risk of progression to cancer compared with non-dysplastic epithelium, but in the majority of patients dysplasia is not subsequently detected.

Endoscopic therapy of Barrett's esophagus

PURPOSE OF REVIEW

Endoscopic therapy for early neoplasia arising in Barrett's esophagus has gained wide acceptance in the USA and Europe, and long-term results of endoscopic resection and photodynamic therapy and new ablation techniques are available now. This review summarizes the different indications for endoscopic treatment and the recent data on the different endoscopic treatment techniques.

RECENT FINDINGS

Endoscopic treatment of high-grade intraepithelial neoplasia has proven to be well tolerated and effective even after a long-term follow-up of more than 5 years. Radiofrequency treatment seems to be an effective technique for ablation of Barrett's esophagus with low and high-grade intraepithelial neoplasia on short-term follow-up with a very low complication rate. Recent data were able to demonstrate that biomarkers can predict the treatment effect of photodynamic therapy and several risk factors for stricture formation after treatment could be identified.

SUMMARY

Endoscopic therapy of early Barrett's neoplasia has proven to be well tolerated and effective and can be considered as the treatment of choice for most patients with this disease. Visible lesions should be treated by endoscopic resection in order to obtain a specimen for histological work up. The remaining nondysplastic Barrett's epithelium after complete resection of all neoplastic lesions should be ablated, for example, by radiofrequency treatment, to prevent metachronous or recurrent neoplasia.

Barrett's esophagus: can biomarkers predict progression to malignancy?

Barrett's esophagus (BE) is one of the most common premalignant lesions and can progress to esophageal adenocarcinoma. It is characterized histologically by a specialized intestinal metaplasia that replaces the squamous epithelium of the distal esophagus, and is associated with chronic gastroesophageal reflux disease and obesity. Similar to the adenoma-carcinoma sequence of colorectal carcinomas, esophageal adenocarcinoma develops through progression from BE to low- and high-grade dysplasia, then to adenocarcinoma with accumulation of genetic and epigenetic abnormalities. The exact malignancy potential of BE is uncertain. Dysplasia is the most predictive marker for risk of esophageal adenocarcinoma, whereas endoscopic and histological diagnoses are still the gold standard for surveillance of patients with BE. However, both are limited, either by sampling errors in biopsies or by differences in histological interpretation. Several studies have identified candidate biomarkers that may have predictive value and may serve as additional factors for the risk assessment of esophageal adenocarcinoma. This review discusses the role of biomarkers in the progression from BE to adenocarcinoma, focusing on clinical and molecular markers.

Endoscopy in Barrett's oesophagus: adherence to standards and neoplasia detection in the community practice versus hospital setting

OBJECTIVE

Potential process differences between hospital and community-based endoscopy for Barrett's oesophagus have not been examined. We aimed at comparing adherence to guidelines and neoplasia detection rates in medical centres (MC) and community practices (CP).

DESIGN

Retrospective analysis.

SETTING

All histologically confirmed Barrett cases seen over a 3-year period in six MC and 19 CP covering a third of all upper gastrointestinal endoscopies (n = 126,000) performed annually in Berlin, Germany.

MAIN OUTCOME MEASURE

Rate of relevant neoplasia (high-grade intraepithelial neoplasia or more) in both settings in relation to adherence to standards.

RESULTS

Of 1317 Barrett cases, 66% were seen in CP. CP patients had a shorter mean Barrett length (2.6 cm vs. 3.8 cm; P < 0.001) with fewer biopsies taken during an examination (2.5 vs. 4.1 for Barrett length <or=2 cm; P < 0.001). CPs also provided fewer complete esophagogastroduodenoscopy documentation (25.1% vs. 57.8%, P < 0.001). Neoplasias were found more commonly in MCs compared to CPs (9.2% vs. 0.8%; P < 0.001). However, on exclusion of all referred patients with known neoplasia (65%) or those examined for other reasons (27.5%), the detection rate at MCs decreased to 1.3%, not different from the one seen at CPs (0.8%, P = 0.43). Only 13% were found during surveillance, but 57% were diagnosed at an early stage.

CONCLUSIONS

Referral bias and not better adherence to guidelines could explain the higher neoplasia prevalence in Barrett's oesophagus at hospital centres. Despite a generally poor adherence to guidelines, most neoplasias found were at an early and potentially curable stage.

Histological assessment of oesophageal columnar mucosa

This review presents the pathological features of Barrett's oesophagus, with an emphasis on the role of pathologists in the diagnosis, surveillance and treatment of the disease. The diagnosis of Barrett's oesophagus is based both on endoscopy and histology. The surveillance of patients relies on systematic biopsy sampling, looking for dysplasia - intraepithelial neoplasia. Well established classifications of dysplasia are now used by pathologists, but there remain problems with this marker. Therefore, many alternative biomarkers have been proposed, that remain of limited interest in daily practice, including DNA-ploidy, proliferation markers, and p53 abnormalities. Endoscopic improvements already allow a better selection of biopsies, and it may be that new technologies will allow 'virtual biopsies'. The role of pathologists is now extended to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection.

Expression of alpha-methylacyl coenzyme A racemase in the dysplasia carcinoma sequence associated with Barrett's esophagus

Two different studies demonstrated alpha-methylacyl coenzyme A racemase (AMACR) to be a highly specific marker in Barrett's neoplastic lesions. Reactive atypia was positive in 3/30 cases in these studies. We present a retrospective study of early Barrett's adenocarcinoma treated with surgery (2000-2005, n=29; M:F=5:1, median age 67 years). We analyzed the role of AMACR expression in reactive and neoplastic lesions associated with the disease of 77 different specimens (60 biopsy and 17 surgical specimens) of these patients. In our cohort, 70% of cases demonstrated infiltration of the submucosa, 38% were poorly differentiated, and/or 31% demonstrated lymph vessel infiltration. We used a multi-tissue array, with reactive and neoplastic samples for each patient to analyze the immunoreactivity of AMACR. Barrett's epithelium that was negative for dysplasia and columnar epithelial cell changes indefinite for dysplasia (n=30) did not demonstrate AMACR immunoreactivity. AMACR immunoreactivity was demonstrated in 27% (8/30) of cases of Barrett's epithelium with columnar epithelial cell changes indefinite for dysplasia. Altogether 91% of cases with low-grade dysplasia were AMACR-positive and 96% of cases with high-grade dysplasia and early Barrett's adenocarcinoma were positive for AMACR. In summary, the sensitivity of AMACR expression in low-grade dysplasia and subsequent early Barrett's adenocarcinoma was significantly higher in our study compared with previous data. This might be a new diagnostic marker for dysplasia carcinoma sequence in Barrett's low-grade neoplastic lesions. Further studies are required to investigate this point with well-defined controls having at least 5-years follow-up.