The diagnosis of low-grade dysplasia in Barrett's esophagus and its implications for disease progression

Organization of surveillance in GI practice

BACKGROUND

Several reports documented an inefficient utilisation of available resources, as well as a suboptimal compliance with surveillance recommendations. Although, evidence suggests that organisational issues can influence the quality of care delivered, surveillance protocols are usually based on non-organized approaches.

METHODS

We conducted a literature search (publication date: 01/2000-06/2016) on PubMed and Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and Cochrane Central Register of Controlled Trials for guidelines, or consensus statements, for surveys of practice, reporting information about patients, or providers attitudes and behaviours, for intervention studies to enhance compliance with guidelines. Related articles were also scrutinised. Based on the clinical relevance and burden on endoscopy services this review was focused on surveillance for Barrett's oesophagus, IBD and post-polypectomy surveillance of colonic adenomas.

RESULTS

Existing guidelines are generally recognising structure and process requirements influencing delivery of surveillance interventions, while less attention had been devoted to transitions and interfaces in the care process. Available evidence from practice surveys is suggesting the need to design organizational strategies aimed to enable patients to attend and providers to deliver timely and appropriate care. Well designed studies assessing the effectiveness of specific interventions in this setting are however lacking. Indirect evidence from screening settings would suggest that the implementation of automated standardized recall systems, utilisation of clinical registries, removing financial barriers, could improve appropriateness of use and compliance with recommendations.

CONCLUSIONS

Lack of sound evidence regarding utility and methodology of surveillance can contribute to explain the observed variability in providers and patients attitudes and in compliance with the recommended surveillance.

Value of cyclin A immunohistochemistry for cancer risk stratification in Barrett esophagus surveillance: A multicenter case-control study

The value of endoscopic Barrett esophagus (BE) surveillance based on histological diagnosis of low-grade dysplasia (LGD) remains debated given the lack of adequate risk stratification. The aim of this study was to evaluate the predictive value of cyclin A expression and to combine these results with our previously reported immunohistochemical p53, AMACR, and SOX2 data, to identify a panel of biomarkers predicting neoplastic progression in BE.We conducted a case-control study within a prospective cohort of 720 BE patients. BE patients who progressed to high-grade dysplasia (HGD, n = 37) or esophageal adenocarcinoma (EAC, n = 13), defined as neoplastic progression, were classified as cases and patients without neoplastic progression were classified as controls (n = 575). Cyclin A expression was determined by immunohistochemistry in all 625 patients; these results were combined with the histological diagnosis and our previous p53, AMACR, and SOX2 data in loglinear regression models. Differences in discriminatory ability were quantified as changes in area under the ROC curve (AUC) for predicting neoplastic progression.Cyclin A surface positivity significantly increased throughout the metaplasia-dysplasia-carcinoma sequences and was seen in 10% (107/1050) of biopsy series without dysplasia, 33% (109/335) in LGD, and 69% (34/50) in HGD/EAC. Positive cyclin A expression was associated with an increased risk of neoplastic progression (adjusted relative risk (RR) 2.4; 95% CI: 1.7-3.4). Increases in AUC were substantial for P53 (+0.05), smaller for SOX2 (+0.014), minor for cyclin A (+0.003), and none for AMARC (0.00).Cyclin A immunopositivity was associated with an increased progression risk in BE patients. However, compared to p53 and SOX2, the incremental value of cyclin A was limited. The use of biomarkers has the potential to significantly improve risk stratification in BE.

Diagnosis and Management of Low-Grade Dysplasia in Barrett's Esophagus: Expert Review From the Clinical Practice Updates Committee of the American Gastroenterological Association

The purpose of this clinical practice update expert review is to define the key principles in the diagnosis and management of low-grade dysplasia (LGD) in Barrett's esophagus patients. The best practices outlined in this review are based on relevant publications, including systematic reviews and expert opinion (when applicable). Practice Advice 1: The extent of Barrett's esophagus should be defined using a standardized grading system documenting the circumferential and maximal extent of the columnar lined esophagus (Prague classification) with a clear description of landmarks and visible lesions (nodularity, ulceration) when present. Practice Advice 2: Given the significant interobserver variability among pathologists, the diagnosis of Barrett's esophagus with LGD should be confirmed by an expert gastrointestinal pathologist (defined as a pathologist with a special interest in Barrett's esophagus-related neoplasia who is recognized as an expert in this field by his/her peers). Practice Advice 3: Expert pathologists should report audits of their diagnosed cases of LGD, such as the frequency of LGD diagnosed among surveillance patients and/or the difference in incidence of neoplastic progression among patients diagnosed with LGD vs nondysplastic Barrett's esophagus. Practice Advice 4: Patients in whom the diagnosis of LGD is downgraded to nondysplastic Barrett's esophagus should be managed as nondysplastic Barrett's esophagus. Practice Advice 5: In Barrett's esophagus patients with confirmed LGD (based on expert gastrointestinal pathology review), repeat upper endoscopy using high-definition/high-resolution white-light endoscopy should be performed under maximal acid suppression (twice daily dosing of proton pump inhibitor therapy) in 8-12 weeks. Practice Advice 6: Under ideal circumstances, surveillance biopsies should not be performed in the presence of active inflammation (erosive esophagitis, Los Angeles grade C and D). Pathologists should be informed if biopsies are obtained in the setting of erosive esophagitis and if pathology findings suggest LGD, or if no biopsies are obtained, surveillance biopsies should be repeated after the anti-reflux regimen has been further intensified. Practice Advice 7: Surveillance biopsies should be performed in a four-quadrant fashion every 1-2 cm with target biopsies obtained from visible lesions taken first. Practice Advice 8: Patients with a confirmed histologic diagnosis of LGD should be referred to an endoscopist with expertise in managing Barrett's esophagus-related neoplasia practicing at centers equipped with high-definition endoscopy and capable of performing endoscopic resection and ablation. Practice Advice 9: Endoscopic resection should be performed in Barrett's esophagus patients with LGD with endoscopically visible abnormalities (no matter how subtle) in order to accurately assess the grade of dysplasia. Practice Advice 10: In patients with confirmed Barrett's esophagus with LGD by expert GI pathology review that persists on a second endoscopy, despite intensification of acid-suppressive therapy, risks and benefits of management options of endoscopic eradication therapy (specifically adverse events associated with endoscopic resection and ablation), and ongoing surveillance should be discussed and documented. Practice Advice 11: Endoscopic eradication therapy should be considered in patients with confirmed and persistent LGD with the goal of achieving complete eradication of intestinal metaplasia. Practice Advice 12: Patients with LGD undergoing surveillance rather than endoscopic eradication therapy should undergo surveillance every 6 months times 2, then annually unless there is reversion to nondysplastic Barrett's esophagus. Biopsies should be obtained in 4-quadrants every 1-2 cm and of any visible lesions. Practice Advice 13: In patients with Barrett's esophagus-related LGD undergoing ablative therapy, radiofrequency ablation should be used. Practice Advice 14: Patients completing endoscopic eradication therapy should be enrolled in an endoscopic surveillance program. Patients who have achieved complete eradication of intestinal metaplasia should undergo surveillance every year for 2 years and then every 3 years thereafter to detect recurrent intestinal metaplasia and dysplasia. Patients who have not achieved complete eradication of intestinal metaplasia should undergo surveillance every 6 months for 1 year after the last endoscopy, then annually for 2 years, then every 3 years thereafter. Practice Advice 15: Following endoscopic eradication therapy, the biopsy protocol of obtaining biopsies in 4 quadrants every 2 cm throughout the length of the original Barrett's esophagus segment and any visible columnar mucosa is suggested. Practice Advice 16: Endoscopists performing endoscopic eradication therapy should report audits of their rates of complete eradication of dysplasia and intestinal metaplasia and adverse events in clinical practice.

Progression from low-grade dysplasia to malignancy in patients with Barrett's esophagus diagnosed by two or more pathologists

AIM

To evaluate annual incidence of low grade dysplasia (LGD) progression to high grade dysplasia (HGD) and/or esophageal adenocarcinoma (EAC) when diagnosis was made by two or more expert pathologists.

METHODS

Studies evaluating the progression of LGD to HGD or EAC were included. The diagnosis of LGD must be made by consensus of two or more expert gastrointestinal pathologists. Articles were searched in Medline, Pubmed, and Embase. Pooled proportions were calculated using fixed and random effects model. Heterogeneity among studies was assessed using the I2 statistic.

RESULTS

Initial search identified 721 reference articles, of which 53 were selected and reviewed. Twelve studies (n = 971) that met the inclusion criteria were included in this analysis. Among the total original LGD diagnoses in the included studies, only 37.49% reached the consensus LGD diagnosis after review by two or more expert pathologists. Total follow up period was 1532 patient-years. In the pooled consensus LGD patients, the annual incidence rate (AIR) of progression to HGD and or EAC was 10.35% (95%CI: 7.56-13.13) and progression to EAC was 5.18% (95%CI: 3.43-6.92). Among the patients down staged from original LGD diagnosis to No-dysplasia Barrett's esophagus, the AIR of progression to HGD and EAC was 0.65% (95%CI: 0.49-0.80). Among the patients down staged to Indefinite for dysplasia, the AIR of progression to HGD and EAC was 1.42% (95%CI: 1.19-1.65). In patients with consensus HGD diagnosis, the AIR of progression to EAC was 28.63% (95%CI: 13.98-43.27).

CONCLUSION

When LGD is diagnosed by consensus agreement of two or more expert pathologists, its progression towards malignancy seems to be at least three times the current estimates, however it could be up to 20 times the current estimates. Biopsies of all Barrett's esophagus patients with LGD should be reviewed by two expert gastroenterology pathologists. Follow-up strict surveillance programs should be in place for these patients.

Current concepts in the diagnosis and pathobiology of intraepithelial neoplasia: A review by organ system

Answer questions and earn CME/CNE In this report, a team of surgical pathologists has provided a review of intraepithelial neoplasia in a host of (but not all) anatomic sites of interest to colleagues in various medical specialties, namely, uterine cervix, ovary, breast, lung, head and neck, skin, prostate, bladder, pancreas, and esophagus. There is more experience with more readily accessible sites (such as the uterine cervix and skin) than with other anatomic sites, and the lack of uniform terminology, together with divergent biology in various sites, makes it difficult to paint a unifying, relevant portrait. The authors' aim was to provide a framework from which to move forward as we care for patients with such precancerous lesions. CA Cancer J Clin 2016;66:408-436. © 2016 American Cancer Society.

Barrett's Esophagus: A Comprehensive and Contemporary Review for Pathologists

This review provides a summary of our current understanding of, and the controversies surrounding, the diagnosis, pathogenesis, histopathology, and molecular biology of Barrett's esophagus (BE) and associated neoplasia. BE is defined as columnar metaplasia of the esophagus. There is worldwide controversy regarding the diagnostic criteria of BE, mainly with regard to the requirement to histologically identify goblet cells in biopsies. Patients with BE are at increased risk for adenocarcinoma, which develops in a metaplasia-dysplasia-carcinoma sequence. Surveillance of patients with BE relies heavily on the presence and grade of dysplasia. However, there are significant pathologic limitations and diagnostic variability in evaluating dysplasia, particularly with regard to the more recently recognized unconventional variants. Identification of non-morphology-based biomarkers may help risk stratification of BE patients, and this is a subject of ongoing research. Because of recent achievements in endoscopic therapy, there has been a major shift in the treatment of BE patients with dysplasia or intramucosal cancer away from esophagectomy and toward endoscopic mucosal resection and ablation. The pathologic issues related to treatment and its complications are also discussed in this review article.

Interobserver agreement among cytopathologists in the evaluation of pancreatic endoscopic ultrasound-guided fine needle aspiration cytology specimens

BACKGROUND AND AIMS

Endoscopic ultrasound with fine needle aspiration (EUS-FNA) has become the standard of care in the evaluation of solid pancreatic lesions. Limited data exist on interobserver agreement (IOA) among cytopathologists in assessing solid pancreatic EUS-FNA specimens. This study aimed to evaluate IOA among cytopathologists in assessing EUS-FNA cytology specimens of solid pancreatic lesions using a novel standardized scoring system and to assess individual clinical and cytologic predictors of IOA.

METHODS

Consecutive patients who underwent EUS-FNA of solid pancreatic lesions at a tertiary care referral center were included. EUS-FNA slides were evaluated by four blinded cytopathologists using a standardized scoring system that assessed final cytologic diagnosis and quantitative (number of nucleated/diagnostic cells) and qualitative (bloodiness, inflammation/necrosis, contamination, artifact) cytologic parameters. Final clinical diagnosis was based on final cytology, surgical pathology, or 1-year clinical follow-up. IOA was calculated using multi-rater kappa (κ) statistics. Bivariate analyses were performed comparing cases with and without uniform agreement among the cytopathologists followed by logistic regression with backward elimination to model likelihood of uniform agreement.

RESULTS

Ninety-nine patients were included (49 % males, mean age 64 years, mean lesion size 26 mm). IOA for final diagnosis was moderate (κ = 0.45, 95 % confidence interval (CI) 0.4 - 0.49) with minimal improvement when combining suspicious and malignant diagnoses (κ = 0.54, 95 %CI 0.49 - 0.6). The weighted kappa value for overall diagnosis was 0.65 (95 %CI 0.54 - 0.76). IOA was slight to fair (κ = 0.04 - 0.32) for individual cytologic parameters. A final clinical diagnosis of malignancy was the most significant predictor of agreement [OR 3.99 (CI 1.52 - 10.49)].

CONCLUSIONS

Interobserver agreement among cytopathologists for pancreatic EUS-FNA specimens is moderate-substantial for the final cytologic diagnosis. The final clinical diagnosis of malignancy was the strongest predictor of agreement. These results have significant implications for patient management and need to be validated in future trials.

Patients With Barrett's Esophagus and Persistent Low-grade Dysplasia Have an Increased Risk for High-grade Dysplasia and Cancer

BACKGROUND & AIMS

In some patients with Barrett's esophagus (BE) and a confirmed diagnosis of low-grade dysplasia (LGD), the LGD is not detected during follow-up examinations. We would like to avoid the unnecessary risks and costs of ablative treatment for these patients. Therefore, we investigated whether persistent LGD increases risk for high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) and what proportion of patients are no longer found to have dysplasia after an initial diagnosis of LGD.

METHODS

In a retrospective study, we collected information on 1579 patients with BE and LGD from 2005 through 2010 by using a nationwide registry of histopathology diagnoses in the Netherlands (PALGA). Confirmed LGD was defined as a diagnosis of LGD that was confirmed by any other pathologist. Persistent LGD was defined as LGD detected at the first and follow-up endoscopy. Data were collected on patients until treatment for HGD, detection of EAC, or the last endoscopy at which a biopsy was collected (through July 2014). We evaluated whether persistent LGD was a risk factor for malignant progression by using univariable and multivariable Cox regression analyses.

RESULTS

Of individuals with BE and LGD in the database, the diagnosis of LGD was confirmed for 161 patients (10% of total). In these patients, the incidence of HGD and/or EAC was 5.18/100 person-years (95% confidence interval [CI], 4.32-8.10/100 person-years) compared with 1.85/100 person-years (95% CI, 1.52-2.22/100 person-years) in patients for whom LGD was not confirmed at the first endoscopy. The incidence of EAC alone in patients with confirmed LGD was 2.51/100 person-years (95% CI, 1.46-3.99/100 person-years), compared with 1.01/per 100 person-years (95% CI, 0.41-2.10/100 person-years) in patients for whom LGD was not confirmed at the first endoscopy. Of patients in whom LGD was confirmed at the first endoscopic examination, 51% were not found to have dysplasia at the first follow-up endoscopy, and 30% had persistent LGD. In patients with persistent LGD, the incidence of HGD and/or EAC was 7.65/100 person-years (95% CI, 4.45-12.34) and of only EAC was 2.04/100 person-years (95% CI, 0.65-4.92); in patients without persistent LGD, the incidence of HGD and/or EAC was 2.32/100 person-years (95% CI, 1.08-4.40/100 person-years) and of only EAC was 1.45 (95% CI, 0.53-3.21/100 person-years). Persistent LGD was found to be an independent risk factor for the development of HGD and/or EAC, with hazard ratio of 3.5 (95% CI, 1.48-8.28).

CONCLUSIONS

In a large population-based cohort study of patients with BE and LGD, the risk of progression to HGD and/or EAC was higher in patients with confirmed LGD and highest in those with confirmed and persistent LGD.

Increasing diagnostic accuracy to grade dysplasia in Barrett's esophagus using an immunohistochemical panel for CDX2, p120ctn, c-Myc and Jagged1

Background

Patients with non-dysplastic Barrett’s esophagus (ND-BE) and low-grade dysplasia (LGD) are typically monitored by periodic endoscopic surveillance, while those with high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) are usually treated by more aggressive interventions like endoscopic mucosal resection, ablation or surgery. Therefore, the accurate grading of dysplasia in Barrett’s esophagus (BE) is essential for proper patient care. However, there is significant interobserver and intraobserver variability in the histologic grading of BE dysplasia. The objective of this study was to create an immunohistochemical (IHC) panel that facilitates the grading of BE dysplasia and can be used as an adjunct to histology in challenging cases.

Methods

100 BE biopsies were re-graded for dysplasia independently by 3 subspecialized gastrointestinal pathologists. IHC staining for CDX2, p120ctn, c-Myc and Jagged1 proteins was then performed and assessed by two separate methods of semi-quantitative scoring. Scores were integrated using a principal component analysis (PCA) and receiver operating characteristic (ROC) curve.

Results

Principal component analysis demonstrated the ability of this panel of proteins to segregate ND-BE/LGD and HGD/EAC, as the expression of the four proteins is significantly altered between the two subsets. Analysis of the receiver operating characteristic curve showed that this panel has the potential to aid in the grading of dysplasia in these two subcategories with both high sensitivity and specificity. While not able to discriminate between ND-BE and LGD, this panel of four proteins may be used as an adjunct to help discriminate subsets of ND-BE/LGD from HGD/EAC.

Conclusions

We propose that the maximum utility of this IHC panel of CDX2, p120ctn, c-Myc, and Jagged1 proteins would be to distinguish between LGD and HGD in histologically challenging cases, given the aggressive interventions still used for HGD in many institutions, and hence may aid in the optimal patient management. The results of this initial study are promising, though further validation is needed before this panel can be used clinically, including future randomized prospective studies with larger patient cohorts from diverse locations.

Electronic supplementary material

The online version of this article (doi:10.1186/s13000-016-0473-7) contains supplementary material, which is available to authorized users.

Analysis of dysplasia in patients with Barrett's esophagus based on expression pattern of 90 genes

BACKGROUND & AIMS

Diagnoses of dysplasia, based on histologic analyses, dictate management decisions for patients with Barrett's esophagus (BE). However, there is much intra- and inter-observer variation in identification of dysplasia-particularly low-grade dysplasia. We aimed to identify a biomarker that could be used to assign patients with low-grade dysplasia to a low- or high-risk group.

METHODS

We performed a stringent histologic assessment of 150 frozen esophageal tissues samples collected from 4 centers in the United Kingdom (from 2000 through 2006). The following samples with homogeneous diagnoses were selected for gene expression profiling: 28 from patients with nondysplastic BE, 10 with low-grade dysplasia, 13 with high-grade dysplasia (HGD), and 8 from patients with esophageal adenocarcinoma. A leave-one-out cross-validation analysis was used identify a gene expression signature associated with HGD vs nondysplastic BE. Functional pathways associated with gene signature sets were identified using the MetaCore analysis. Gene expression signature sets were validated using gene expression data on BE and esophageal adenocarcinoma accessed through National Center for Biotechnology Information Gene Expression Omnibus, as well as a separate set of samples (n = 169) collected from patients who underwent endoscopy in the United Kingdom or the Netherlands and analyzed histologically.

RESULTS

We identified an expression pattern of 90 genes that could separate nondysplastic BE tissues from those with HGD (P < .0001). Genes in a pathway regulated by retinoic acid-regulated nuclear protein made the largest contribution to this gene set (P < .0001); the transcription factor MYC regulated at least 30% of genes within the signature (P < .0001). In the National Center for Biotechnology Information Gene Expression Omnibus validation set, the signature separated nondysplastic BE samples from esophageal adenocarcinoma samples (P = .0012). In the UK and Netherlands validation cohort, the signature identified dysplastic tissues with an area under the curve value of 0.87 (95% confidence interval: 0.82-0.93). Of samples with low-grade dysplasia (LGD), 64% were considered high risk according to the 90-gene signature; these patients had a higher rate of disease progression than those with a signature categorized as low risk (P = .047).

CONCLUSIONS

We identified an expression pattern of 90 genes in esophageal tissues of patients with BE that was associated with low- or high-risk for disease progression. This pattern might be used in combination with histologic analysis of biopsy samples to stratify patients for treatment. It would be most beneficial for analysis of patients without definitive evidence of HGD but for whom early endoscopic intervention is warranted.

SOX2 as a novel marker to predict neoplastic progression in Barrett's esophagus

OBJECTIVES

The value of Barrett's esophagus (BE) surveillance based on the histological diagnosis of low-grade dysplasia (LGD) remains debated given the lack of adequate risk stratification. The aim of this study was to evaluate the predictive value (PV) of SOX2 expression for neoplastic progression in BE patients.

METHODS

We conducted a case-control study within a prospective cohort of 720 BE patients. Patients with neoplastic progression, defined as the development of high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC), were classified as cases and patients without neoplastic progression were classified as controls. SOX2 expression was determined by immunohistochemistry in more than 12,000 biopsies from 635 patients; these results were combined with our previous p53 immunohistochemical data.

RESULTS

Nondysplastic BE showed homogeneous nuclear staining for SOX2, whereas SOX2 was progressively lost in dysplastic BE. Loss of SOX2 was seen in only 2% of biopsy series without dysplasia, in contrast to 28% in LGD and 67% in HGD/EAC. Loss of SOX2 expression was associated with an increased risk of neoplastic progression in BE patients after adjusting for gender, age, BE length, and esophagitis (adjusted relative risk 4.8; 95% CI 3.2-7.0). The positive PV for neoplastic progression increased from 16% with LGD alone to 56% with concurrent loss of SOX2 and aberrant p53 expression.

CONCLUSIONS

SOX2 expression is lost during transition from nondysplastic BE to HGD/EAC, and it is associated with an increased risk of neoplastic progression. The highest PV is achieved by concurrent loss of SOX2 and aberrant p53 expression in BE patients with LGD. The use of these markers has the potential to significantly improve risk stratification of Barrett surveillance.

Radiofrequency Ablation Is Associated With Decreased Neoplastic Progression in Patients With Barrett's Esophagus and Confirmed Low-Grade Dysplasia

BACKGROUND & AIMS

Barrett's esophagus (BE) with low-grade dysplasia (LGD) can progress to high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Radiofrequency ablation (RFA) has been shown to be an effective treatment for LGD in clinical trials, but its effectiveness in clinical practice is unclear. We compared the rate of progression of LGD after RFA with endoscopic surveillance alone in routine clinical practice.

METHODS

We performed a retrospective study of patients who either underwent RFA (n = 45) or surveillance endoscopy (n = 125) for LGD, confirmed by at least 1 expert pathologist, from October 1992 through December 2013 at 3 medical centers in the United States. Cox regression analysis was used to assess the association between progression and RFA.

RESULTS

Data were collected over median follow-up periods of 889 days (interquartile range, 264-1623 days) after RFA and 848 days (interquartile range, 322-2355 days) after surveillance endoscopy (P = .32). The annual rates of progression to HGD or EAC were 6.6% in the surveillance group and 0.77% in the RFA group. The risk of progression to HGD or EAC was significantly lower among patients who underwent RFA than those who underwent surveillance (adjusted hazard ratio = 0.06; 95% confidence interval: 0.008-0.48).

CONCLUSIONS

Among patients with BE and confirmed LGD, rates of progression to a combined end point of HGD and EAC were lower among those treated with RFA than among untreated patients. Although selection bias cannot be excluded, these findings provide additional evidence for the use of endoscopic ablation therapy for LGD.

Molecular biomarkers added to image-enhanced endoscopic imaging: will they further improve diagnostic accuracy?

Barrett's esophagus (BE) is a premalignant condition for esophageal adenocarcinoma (EAC) which has dismal prognosis. The risk of progression from BE to EAC increases with dysplasia grade. The purpose of surveillance exams in BE is to detect dysplasia at an early stage and intervene before development of EAC. However, the current surveillance practices have not been effective in reducing EAC incidence. Major limitations of this strategy include challenges in identifying dysplasia during endoscopic surveillance, which leads to sampling error and subjectivity in the histological diagnosis of dysplasia due to interobserver variation amongst pathologists. Advanced imaging techniques may allow targeted biopsy of suspicious foci with incremental yield in dysplasia detection and reduce sampling error. Molecular biomarker panels have the potential to objectively assess progression risk without the subjectivity associated with histology. Combining molecular markers with advanced imaging appears to be a promising strategy to further improve risk stratification and reduce EAC incidence and mortality. Few studies have investigated this strategy so far and the results are promising. Further research on different permutations between the available biomarkers and imaging techniques will help us determine the best possible combination that detects dysplasia with high sensitivity and specificity. Further research is needed to establish the combined strategy's cost effectiveness and feasibility.

The changing role of the pathologist in the management of Barrett's oesophagus

Pathological specimens from columnar-lined oesophagus (CLO) comprise a considerable proportion of the workload of gastrointestinal pathologists in Western countries. There remain controversies concerning the diagnostic role of pathology. More recently, in the UK at least, the diagnosis has been regarded as primarily an endoscopic endeavour, with pathology being corroborative and only diagnostic when endoscopic features are equivocal or when there are additional features that make the endoscopic diagnosis unclear. There is also recognition that demonstration of intestinalisation or 'goblet cells' is not paramount, and should not be required for the diagnosis. There have been notable changes in the management of CLO neoplasia: pathologists are centrally involved in its management. Pathological assessment of endoscopic mucosal resection (EMR) specimens provides the most useful means of determining the management of early neoplasia and of determining indications for surgery. This represents an extraordinarily rapid change in management, in that, <10 years ago, laborious Seattle-type biopsy protocols were recommended, and high grade dysplasia was an indication for resectional surgery. Now, individual patient management is paramount: multi-professional meetings determine management after biopsy and EMR assessment. One significant change is that major resections are undertaken less often, in Western countries, for CLO neoplasia.

Evaluation of Mutational Testing of Preneoplastic Barrett's Mucosa by Next-Generation Sequencing of Formalin-Fixed, Paraffin-Embedded Endoscopic Samples for Detection of Concurrent Dysplasia and Adenocarcinoma in Barrett's Esophagus

Barrett's intestinal metaplasia (BIM) may harbor genomic mutations before the histologic appearance of dysplasia and cancer and requires frequent surveillance. We explored next-generation sequencing to detect mutations with the analytical sensitivity required to predict concurrent high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) in patients with Barrett's esophagus by testing nonneoplastic BIM. Formalin-fixed, paraffin-embedded (FFPE) routine biopsy or endoscopic mucosal resection samples from 32 patients were tested: nonprogressors to HGD or EAC (BIM-NP) with BIM, who never had a diagnosis of dysplasia or EAC (N = 13); progressors to HGD or EAC (BIM-P) with BIM and a worse diagnosis of HGD or EAC (N = 15); and four BIM-negative samples. No mutations were detected in the BIM-NP (0 of 13) or BIM-negative samples, whereas the BIM-P samples had mutations in 6 (75%) of 8 cases in TP53, APC, and CDKN2A (P = 0.0005), detected in samples with as low as 20% BIM. We found that next-generation sequencing from routine FFPE nonneoplastic Barrett's esophagus samples can detect multiple mutations in minute areas of BIM with high analytical sensitivity. Next-generation sequencing panels for detection of TP53 and possibly combined mutations in other genes, such as APC and CDKN2A, may be useful in the clinical setting to improve dysplasia and cancer surveillance in patients with Barrett's esophagus.

Recent developments in pathogenesis, diagnosis and therapy of Barrett's esophagus

The burden of illness from esophageal adenocarcinoma continues to rise in the Western world, and overall prognosis is poor. Given that Barrett’s esophagus (BE), a metaplastic change in the esophageal lining is a known cancer precursor, an opportunity to decrease disease development by screening and surveillance might exist. This review examines recent updates in the pathogenesis of BE and comprehensively discusses known risk factors. Diagnostic definitions and challenges are outlined, coupled with an in-depth review of management. Current challenges and potential solutions related to screening and surveillance are discussed. The effectiveness of currently available endoscopic treatment techniques, particularly with regards to recurrence following successful endotherapy and potential chemopreventative agents are also highlighted. The field of BE is rapidly evolving and improved understanding of pathophysiology, combined with emerging methods for screening and surveillance offer hope for future disease burden reduction.

Epidemiology of Barrett's Esophagus and Esophageal Adenocarcinoma

Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC), a disease with increasing burden in the Western world, especially in white men. Risk factors for BE include obesity, tobacco smoking, and gastroesophageal reflux disease (GERD). EAC is the most common form of esophageal cancer in the United States. Risk factors include GERD, tobacco smoking, and obesity, whereas nonsteroidal antiinflammatory drugs and statins may be protective. Factors predicting progression from nondysplastic BE to EAC include dysplastic changes on esophageal histology and length of the involved BE segment. Biomarkers have shown promise, but none are approved for clinical use.

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.

Quantitative evaluation of in vivo vital-dye fluorescence endoscopic imaging for the detection of Barrett's-associated neoplasia

Current imaging tools are associated with inconsistent sensitivity and specificity for detection of Barrett's-associated neoplasia. Optical imaging has shown promise in improving the classification of neoplasia in vivo. The goal of this pilot study was to evaluate whether in vivo vital dye fluorescence imaging (VFI) has the potential to improve the accuracy of early-detection of Barrett's-associated neoplasia. In vivo endoscopic VFI images were collected from 65 sites in 14 patients with confirmed Barrett's esophagus (BE), dysplasia, oresophageal adenocarcinoma using a modular video endoscope and a high-resolution microendoscope(HRME). Qualitative image features were compared to histology; VFI and HRME images show changes in glandular structure associated with neoplastic progression. Quantitative image features in VFI images were identified for objective image classification of metaplasia and neoplasia, and a diagnostic algorithm was developed using leave-one-out cross validation. Three image features extracted from VFI images were used to classify tissue as neoplastic or not with a sensitivity of 87.8% and a specificity of 77.6% (AUC = 0.878). A multimodal approach incorporating VFI and HRME imaging can delineate epithelial changes present in Barrett's-associated neoplasia. Quantitative analysis of VFI images may provide a means for objective interpretation of BE during surveillance.

BOB CAT: A Large-Scale Review and Delphi Consensus for Management of Barrett's Esophagus With No Dysplasia, Indefinite for, or Low-Grade Dysplasia

OBJECTIVES

Barrett's esophagus (BE) is a common premalignant lesion for which surveillance is recommended. This strategy is limited by considerable variations in clinical practice. We conducted an international, multidisciplinary, systematic search and evidence-based review of BE and provided consensus recommendations for clinical use in patients with nondysplastic, indefinite, and low-grade dysplasia (LGD).

METHODS

We defined the scope, proposed statements, and searched electronic databases, yielding 20,558 publications that were screened, selected online, and formed the evidence base. We used a Delphi consensus process, with an 80% agreement threshold, using GRADE (Grading of Recommendations Assessment, Development and Evaluation) to categorize the quality of evidence and strength of recommendations.

RESULTS

In total, 80% of respondents agreed with 55 of 127 statements in the final voting rounds. Population endoscopic screening is not recommended and screening should target only very high-risk cases of males aged over 60 years with chronic uncontrolled reflux. A new international definition of BE was agreed upon. For any degree of dysplasia, at least two specialist gastrointestinal (GI) pathologists are required. Risk factors for cancer include male gender, length of BE, and central obesity. Endoscopic resection should be used for visible, nodular areas. Surveillance is not recommended for <5 years of life expectancy. Management strategies for indefinite dysplasia (IND) and LGD were identified, including a de-escalation strategy for lower-risk patients and escalation to intervention with follow-up for higher-risk patients.

CONCLUSIONS

In this uniquely large consensus process in gastroenterology, we made key clinical recommendations for the escalation/de-escalation of BE in clinical practice. We made strong recommendations for the prioritization of future research.

Toll-like receptor 9 expression in the natural history of Barrett mucosa

Increased expression of TLR9 in esophageal adenocarcinoma and squamous cell carcinoma correlates with poor prognosis. We have explored the expression and suspected that TLR9 activation might contribute to pathogenesis in esophageal columnar metaplasia-dysplasia-neoplasia sequence, and hence, we have studied the usefulness of TLR9 as a marker for dysplasia. We have determined the expression of TLR9 in specimens with normal esophagus (n = 89), gastric (n = 71), or intestinal metaplasia (n = 56) without dysplasia, and low-grade (n = 51) or high-grade dysplasia (n = 40), and esophageal adenocarcinoma (n = 88). We observed linearly increasing TLR9 expression in specimens to be associated with change from normal epithelium to columnar metaplasia and further to dysplasia. ROC curve analysis showed clinically irrelevant sensitivity of 71% and specificity of 67% for TLR9 intensity in detection of low-grade dysplasia. Membrane-associated TLR9 expression detected by immunohistochemistry and immunofluorescence was predominantly associated with foveolar-type dysplasia as detected by HE staining (p = 0.015). TLR9 is expressed in Barrett's esophagus, and dissolution of TLR9 staining increases from nondysplastic epithelium to dysplastic. TLR9 may serve as a new way of recognizing the histopathological origin of dysplasia (adenomatous vs foveolar) with observed subcellular pattern of TLR9.

Risk stratification of patients with barrett's esophagus and low-grade dysplasia or indefinite for dysplasia

BACKGROUND & AIMS

In patients with Barrett's esophagus (BE), low-grade dysplasia (LGD) is a risk factor for esophageal adenocarcinoma (EAC), progressing at variable rates. Patients at higher risk for progression could benefit from intervention. We assessed rates of progression of LGD and indefinite for dysplasia (IND) and risk factors for progression to high-grade dysplasia (HGD) and EAC.

METHODS

We analyzed data from Cleveland Clinic Barrett's Registry on patients with BE and LGD or IND at least 1 year of follow-up from January 1, 2002 through December 31, 2012. Prevalent cases were those diagnosed at or within 1 year of the first endoscopy, and the rest were incident cases.

RESULTS

Among 299 patients with BE and LGD or IND, there were 32 cases of HGD and 10 cases of EAC during a follow-up period of 1577.4 patient-years. The annual incidence rates were 2.4% (95% confidence interval [CI], 1.7%-3.3%) for HGD, 0.6% (95% CI, 0.3%-1.2%) for EAC, and 2.7% (95% CI, 1.9%-3.6%) for HGD or EAC. The rates were higher in men than in women with BE and LGD or IND. Prevalent cases were 3-fold more likely to progress than incident cases. Multifocality and nodules were associated with higher risk of progression to HGD or EAC. None of the patients with IND at index biopsy developed EAC. For every 5-year increase in age, chance of regression increased by 7% (P = .04). Also, for every 1-cm increase in BE length, probability of regression decreased by 6% (P = .016). LGD at index biopsy was associated with 56% lower chance of regression compared with IND (P < .001).

CONCLUSIONS

On the basis of a database analysis of patients with BE, prevalent LGD, male sex, multifocality, and nodules were associated with higher risk for progression to EAC. Older age at LGD diagnosis, IND at index biopsy, and shorter BE length were associated with regression. These findings help in risk stratification of patients with BE and LGD or IND.

Barrett's oesophagus diagnostic criteria: endoscopy and histology

This review summarizes the endoscopic and histologic features of Barrett's oesophagus(BO) as well as some of the recent advancements and controversies. BO represents metaplastic conversion of normal squamous epithelium of tubular oesophagus to columnar epithelium. The diagnosis of BO requires a combination of endoscopic and histopathologic findings. There is worldwide controversy regarding the exact definition of BO, particularly with regard to the requirement to histologically identify goblet cells in biopsies. The presence and detectability of goblet cells might vary depending on a variety of factors and is subject to sampling error. Therefore, a systematic biopsy sampling with sufficient number of biopsies is currently recommended to limit the likelihood of a false negative result for detection of goblet cells. There are both endoscopic and pathologic challenges in evaluating gastro-oesophageal junction biopsies in patients with irregular Z lines to determine the exact location of the sample (i.e., oesophagus versus stomach). Recently, several novel endoscopic techniques have been developed to improve BO detection. However, none have been validated yet in clinical practice. The surveillance of patients with BO relies on histologic evaluation of dysplasia. However, there are significant pathologic limitations and diagnostic variability in evaluating the presence and grading of BO dysplasia, particularly with regard to the more recently recognized non-intestinal types of dysplasia. All BO dysplasia samples should be reviewed by an expert gastrointestinal pathologist to confirm the diagnosis. Finally, it is important to emphasize that close interaction between gastroenterologists and pathologists is essential to ensure proper evaluation of endoscopic biopsies in order to optimize the surveillance and clinical management of patients with BO.

Utility of liquid-based cytologic examination of distal esophageal brushings in the management of Barrett esophagus: a prospective study of 45 cases

INTRODUCTION

The goal of Barrett esophagus surveillance is to identify high-grade dysplasia (HGD) for eradication. Surveillance programs currently rely on limited histologic sampling; however, the role of cytology in this setting is not well studied.

MATERIALS AND METHODS

From December 1, 2011 to March 30, 2014, 45 patients underwent 4 circumferential brushings of the distal tubular esophagus followed by standard 4-quadrant biopsies. One ThinPrep slide and 1 Cellient cellblock (Hologic, Boxborough, Mass) were prepared. Six cytopathologists evaluated each for adequacy, intestinal metaplasia (IM) and dysplasia. Findings were classified using the traditional 5-tier system used for biopsies. A prospectively modified 3-tier cytologic classification was also tested: negative for HGD, indeterminate for HGD, and HGD. Sensitivity, specificity, and kappa values (interobserver agreement) for cytology were calculated.

RESULTS

Ten of 45 patients had nondiagnostic cytologies; none of whom had dysplasia on biopsy. Cytology had good sensitivity (82%) and specificity (88%) for identifying IM compared with biopsy with moderate interobserver agreement (pairwise average of Fleiss and Krippendorf kappa value = 0.589, 79% agreement). One case had IM on cytology not detected on histology. Six of 45 patients had dysplasia on biopsy including 1 intramucosal adenocarcinoma, 1 indeterminate for dysplasia, 2 high-grade dysplasias, and 2 low-grade dysplasias. A non-negative adequate cytology sample had a sensitivity of 100% and a specificity of 88% and 94% for the 5-tier and the 3-tier classification, respectively.

CONCLUSIONS

Cytology appears to have good sensitivity and specificity for diagnosis of HGD, and cytology may be poised to synergize with advances in other techniques for management of patients with Barrett esophagus. Improvements in brushing devices may help to decrease the nondiagnostic rate.

The combination of autofluorescence endoscopy and molecular biomarkers is a novel diagnostic tool for dysplasia in Barrett's oesophagus

OBJECTIVE

Endoscopic surveillance for Barrett's oesophagus (BO) is limited by sampling error and the subjectivity of diagnosing dysplasia. We aimed to compare a biomarker panel on minimal biopsies directed by autofluorescence imaging (AFI) with the standard surveillance protocol to derive an objective tool for dysplasia assessment.

DESIGN

We performed a cross-sectional prospective study in three tertiary referral centres. Patients with BO underwent high-resolution endoscopy followed by AFI-targeted biopsies. 157 patients completed the biopsy protocol. Aneuploidy/tetraploidy; 9p and 17p loss of heterozygosity; RUNX3, HPP1 and p16 methylation; p53 and cyclin A immunohistochemistry were assessed. Bootstrap resampling was used to select the best diagnostic biomarker panel for high-grade dysplasia (HGD) and early cancer (EC). This panel was validated in an independent cohort of 46 patients.

RESULTS

Aneuploidy, p53 immunohistochemistry and cyclin A had the strongest association with dysplasia in the per-biopsy analysis and, as a panel, had an area under the receiver operating characteristic curve of 0.97 (95% CI 0.95 to 0.99) for diagnosing HGD/EC. The diagnostic accuracy for HGD/EC of the three-biomarker panel from AFI+ areas was superior to AFI- areas (p<0.001). Compared with the standard protocol, this panel had equal sensitivity for HGD/EC, with a 4.5-fold reduction in the number of biopsies. In an independent cohort of patients, the panel had a sensitivity and specificity for HGD/EC of 100% and 85%, respectively.

CONCLUSIONS

A three-biomarker panel on a small number of AFI-targeted biopsies provides an accurate and objective diagnosis of dysplasia in BO. The clinical implications have to be studied further.

Surveillance for low-grade dysplastic Barrett's oesophagus: one size fits all?

This paper reviews the role of low-grade dysplasia (LGD) as a marker of progression in Barrett's oesophagus (BO). Albeit with its limits due to the difficulty of its diagnosis and the low agreement among pathologists, LGD remains the most relevant single prognostic factor of progression, and, when the diagnosis is confirmed by two or three pathologists, the chances of progression to high-grade dysplasia or invasive adenocarcinoma are as high as 40%. On the other hand, BO patients who remain dysplasia free at several follow-up examinations seem to have a very low likelihood of progression. The diagnosis of LGD should be confirmed by two pathologists, and surveillance programs should be tailored depending on the presence or persistent absence of LGD. Ablative therapy should be also considered for cases where LGD persists in a series of follow-ups.

Consistency of a high-grade dysplasia diagnosis in Barrett's oesophagus: a Dutch nationwide cohort study

BACKGROUND

Consistency of high-grade dysplasia in Barrett's oesophagus is incompletely known and the clinical course may vary between patients.

AIMS

To evaluate the consistency of high-grade dysplasia diagnosis in a Dutch nationwide cohort and to identify predictors for (re-)detecting high-grade dysplasia or oesophageal adenocarcinoma when ≥ 1 follow-up evaluations after an initial high-grade dysplasia diagnosis were scored with a lower histological grade.

METHODS

In this retrospective cohort study, all patients diagnosed with high-grade dysplasia in Barrett's oesophagus between 1999 and 2008 in the Netherlands were selected using the nationwide histopathology registry. Multivariate analysis was performed to identify predictors for (re-)detecting high-grade dysplasia or oesophageal adenocarcinoma in patients with ≥ 1 follow-up evaluations scored with a lower grade.

RESULTS

In total, 512 high-grade dysplasia patients were included, of whom 53% had ≥ 1 follow-up evaluations scored with a lower grade. The (re-)detection risk was increased when follow-up was performed in a university hospital and when endoscopic/surgical resection was performed and decreased with an increasing number of follow-up evaluations scored with a lower grade.

CONCLUSION

High-grade dysplasia diagnosis was inconsistent in more than half of patients. (Endoscopic) resection in an expert centre is recommended to (re-)detect high-grade dysplasia or oesophageal adenocarcinoma when an endoscopic follow-up protocol with biopsies repeatedly shows a lower histological grade.

Barrett esophagus: diagnostic challenges

The incidence of esophageal adenocarcinoma and associated mortality has risen dramatically over the past several decades, and, thus, it is increasingly important to understand its pathogenesis and risk factors. Barrett esophagus is the established precursor to esophageal adenocarcinoma that progresses through a metaplasia-dysplasia-carcinoma sequence. Its risk of transforming to carcinoma is not as high as previously reported and there appears to be a biological heterogeneity among patients with this disease. The overall prevalence of Barrett esophagus in the United States ranges from 1% to 25% and is closer to 5% in patients with gastroesophageal reflux disease. Because of the frequency of Barrett esophagus and associated implications, it is important for the practicing pathologist to have a thorough understanding of this disease and its diagnostic pitfalls. In this review, we will discuss issues associated with the diagnosis of Barrett esophagus, including the definition of Barrett esophagus and its distinction from carditis with intestinal metaplasia. We will also discuss challenges in the grading of dysplasia and new variants of dysplasia, including crypt dysplasia and foveolar-type dysplasia. Finally, we will touch upon the evaluation of dysplasia in endoscopic mucosal resection specimens.

I-SCAN targeted versus random biopsies in Barrett's oesophagus

BACKGROUND

The accuracy and effectiveness of targeted oesophageal biopsies in Barrett's oesophagus to detect dysplasia using new magnification techniques are unknown. Aim of this study was to investigate whether the combined use of acetic acid, magnification and electronic filters allows the same accuracy as the four-quadrant random biopsies pattern; pathologist interobserver agreement both in low grade and high grade dysplasia was also assessed.

METHODS

Fifty-four consecutive patients newly diagnosed with Barrett's oesophagus were enrolled in a prospective study from a single endoscopy unit. Biopsies were evaluated by the local pathologist and by an expert pathologist from another pathology unit.

MAIN OUTCOME MEASUREMENT

Dysplasia detection rate and interobserver agreement for the histologic diagnosis of dysplasia.

RESULTS

The use of acetic acid, magnification and electronic filters showed an unacceptably low dysplasia detection rate by the two pathologists (9.2% and 5.5% for targeted biopsies, respectively). The interobserver agreement for low grade dysplasia between pathologists was low (Cohen's K weighted=0.45).

CONCLUSIONS

In an average setting, the standard four-quadrant method should still be preferred, along with the implementation of a routine second evaluation by an expert pathologist.

Histopathology in barrett esophagus and barrett esophagus-related dysplasia

Pathologic specimens, both biopsies and endoscopic mucosal resections, for Barrett esophagus and Barrett-associated dysplasia and malignancy are common for pathologists in North America, and the incidence in South Asian countries seems to be increasing. Dysplasia and malignancy arising in intestinalized gastric-type mucosa raises issues in the interpretation of dysplasia and the evaluation of the depth of invasion of malignancies that are not seen in squamous dysplasia and squamous cell carcinoma. We review the North American approach to these lesions.

Cost-effectiveness of Barrett's oesophagus screening and surveillance

Endoscopic screening and surveillance of patients with Barrett's oesophagus to detect oesophageal cancer at earlier stages is contentious. As a consequence, their cost-effectiveness is also debatable. Current health economic evidence shows mixed results for demonstrating their value, mainly due to varied assumptions around progression rates to cancer, quality of life and treatment pathways. No randomized controlled trial exists to definitively support the efficacy of surveillance programs and one is unlikely to be undertaken. Contemporary treatment, cost and epidemiological data to contribute to cost-effectiveness analyses are needed. Risk assessment to stratify patients at low- or high-risk of developing cancer should improve cost-effectiveness outcomes as higher gains will be seen for those at higher risk, and medical resource use will be avoided in those at lower risk. Rapidly changing technologies for imaging, biomarker testing and less-invasive endoscopic treatments also promise to lower health system costs and avoid adverse events in patients.

Aberrant p53 protein expression is associated with an increased risk of neoplastic progression in patients with Barrett's oesophagus

OBJECTIVE

The value of surveillance for patients with Barrett's oesophagus (BO) is under discussion given the overall low incidence of neoplastic progression and lack of discriminative tests for risk stratification. Histological diagnosis of low-grade dysplasia (LGD) is the only accepted predictor for progression to date, but has a low predictive value. The aim of this study was therefore to evaluate the value of p53 immunohistochemistry for predicting neoplastic progression in patients with BO.

DESIGN

We conducted a case-control study within a prospective cohort of 720 patients with BO. Patients who developed high-grade dysplasia (HGD) or oesophageal adenocarcinoma (OAC) were classified as cases and patients without neoplastic progression were classified as controls. P53 protein expression was determined by immunohistochemistry in more than 12 000 biopsies from 635 patients and was scored independently by two expert pathologists who were blinded to long-term outcome.

RESULTS

During follow-up, 49 (8%) patients developed HGD or OAC. P53 overexpression was associated with an increased risk of neoplastic progression in patients with BO after adjusting for age, gender, Barrett length and oesophagitis (adjusted relative risks (RR(a)) 5.6; 95% CI 3.1 to 10.3), but the risk was even higher with loss of p53 expression (RR(a) 14.0; 95% CI 5.3 to 37.2). The positive predictive value for neoplastic progression increased from 15% with histological diagnosis of LGD to 33% with LGD and concurrent aberrant p53 expression.

CONCLUSIONS

Aberrant p53 protein expression is associated with an increased risk of neoplastic progression in patients with BO and appears to be a more powerful predictor of neoplastic progression than histological diagnosis of LGD.

Increased Toll-like receptor 5 expression indicates esophageal columnar dysplasia

Toll-like receptor 5 (TLR5) is an immune receptor, which recognizes bacterial flagellin. Increased expression has been reported in various premalignant and malignant lesions indicating a role in carcinogenesis. We assessed the expression of TLR5 in normal esophageal squamous epithelium, Barrett's esophagus with and without dysplasia, and in esophageal adenocarcinoma. Specimens with normal esophagus (n=93), gastric (n=75) or intestinal metaplasia (n=53) without dysplasia, and low-grade (n=56) or high-grade dysplasia (n=33) and esophageal adenocarcinoma (n=94) were studied. TLR5 immunohistochemical stainings were analyzed for the proportion of positive cells and the intensity of expression. In normal squamous epithelium, only the basal third showed TLR5 expression. In esophageal gastric or intestinal metaplasia, expression was present in majority of the cells but significantly weaker (p<0.001) than in dysplastic epithelium. In dysplasia, expression extended to the apical cytoplasm, contrasting basolateral expression in non-dysplastic columnar epithelium. Receiver operating characteristic curve analysis showed that moderate to high expression intensity of TLR5 indicates low-grade dysplasia with 86 % sensitivity and 83 % specificity. Carcinomas showed increased expression in comparison with non-dysplastic columnar epithelium, but there was no association with prognosis. Our results indicate that the esophageal columnar dysplasia is associated with clear increase of TLR5 expression and dissolution of regular polarized expression. TLR5 staining provides a possible biomarker for the recognition of low-grade dysplasia. In addition, the findings suggest a role for abnormal expression of TLR5 in the pathogenesis of esophageal adenocarcinoma and suggest importance of altered microbiome in the pathogenesis of complications of Barrett's esophagus.

Photodynamic therapy vs radiofrequency ablation for Barrett's dysplasia: efficacy, safety and cost-comparison

AIM

To compare effectiveness, safety, and cost of photodynamic therapy (PDT) and radiofrequency ablation (RFA) in treatment of Barrett's dysplasia (BD).

METHODS

Consecutive case series of patients undergoing either PDT or RFA treatment at single center by a single investigator were compared. Thirty-three patients with high-grade dysplasia (HGD) had treatment with porfimer sodium photosensitzer and 630 nm laser (130 J/cm), with maximum of 3 treatment sessions. Fifty-three patients with BD (47 with low-grade dysplasia -LGD, 6 with HGD) had step-wise circumferential and focal ablation using the HALO system with maximum of 4 treatment sessions. Both groups received proton pump inhibitors twice daily. Endoscopic biopsies were acquired at 2 and 12 mo after enrollment, with 4-quadrant biopsies every 1 cm of the original BE extent. A complete histological resolution response of BD (CR-D) was defined as all biopsies at the last endoscopy session negative for BD. Fisher's exact test was used to assess differences between the two study groups for primary outcomes. For all outcomes, a two-sided P value of less than 0.05 was considered to indicate statistical significance.

RESULTS

Thirty (91%) PDT patients and 39 (74%) RFA were men (P = 0.05). The mean age was 70.7 ± 12.2 and 65.4 ± 12.7 (P = 0.10) year and mean length of BE was 5.4 ± 3.2 cm and 5.7 ± 3.2 cm (P = 0.53) for PDT and RFA patients, respectively. The CR-D was (18/33) 54.5% with PDT vs (47/53) 88.7% with RFA (P = 0.001). One patient with PDT had an esophageal perforation and was managed with non-surgical measures and no perforation was seen with RFA. PDT was five times more costly than RFA at our institution. The two groups were not randomized and had different BD grading are the limitations of the study.

CONCLUSION

In our experience, RFA had higher rate of CR-D without any serious adverse events and was less costly than PDT for endoscopic treatment of BD.

Risk factors for rising incidence of esophageal and gastric cardia adenocarcinoma

INTRODUCTION

In the last 30 years, the incidence of esophageal and gastric cardia adenocarcinoma has steadily increased. The increase in incidence is approximately seven-fold, which is a more substantial increase than that of several malignancies, including melanoma, breast cancer, and prostate cancer.

DISCUSSION

The rising incidence has led to a steady increase in mortality from 2 to 15 deaths per 100,000 in the last three decades. The etiologic factors involved in the development of these malignancies include gastroesophageal reflux disease, Barrett's esophagus, acid-suppressive medication use, obesity, and tobacco use. This article discusses the contribution of these etiologic risk factors to this increase in incidence.

Value of α-methylacyl-CoA racemase immunochemistry for predicting neoplastic progression in Barrett's oesophagus

AIM

To investigate the value of α-methylacyl-CoA racemase (AMACR) immunohistochemistry for predicting neoplastic progression in Barrett's oesophagus (BO).

METHODS AND RESULTS

We conducted a case-control study within a prospective cohort of 720 BO patients. Patients who developed high-grade dysplasia or oesophageal adenocarcinoma were classified as cases, and patients without neoplastic progression as controls. AMACR expression was determined by immunohistochemistry in 12 127 biopsies from 635 patients, and was scored independently by two expert pathologists. Relative risks adjusted for age, gender, BO length and oesophagitis (RR(a)) were calculated in log-linear models. During a median follow-up of 6.6 years, 49 patients (8%) developed high-grade dysplasia or oesophageal adenocarcinoma. Although mild AMACR expression was associated with a trend towards an increased risk of neoplastic progression (RR(a) 1.6, 95% CI 0.9-3.1), the risk was especially elevated with strong AMACR expression (RR(a) 4.8, 95% CI 1.9-12.6). The positive predictive value of strong AMACR expression was slightly higher than that of low-grade dysplasia (22% versus 15%); the negative predictive value was slightly lower (91% versus 93%).

CONCLUSIONS

Strong AMACR expression is associated with an increased risk of neoplastic progression in BO. However, AMACR expression appears to be a less powerful predictor for neoplastic progression than low-grade dysplasia.

Barrett Esophagus: Evolving Concepts in Diagnosis and Neoplastic Progression

Surgical pathologists need to answer 2 questions when evaluating biopsies from the distal esophagus or gastroesophageal junction in patients with a history of gastroesophageal reflux disease: Are the findings consistent with Barrett esophagus? and Is there any evidence of dysplasia? Pathologists should be well informed about the controversy around the definition of Barrett esophagus and the common pitfalls that lead to a false-positive diagnosis of Barrett esophagus or Barrett esophagus-associated dysplasia. A concise description of distinct morphologic types of dysplasia in Barrett esophagus and a summary of recent data on the natural history of BE are provided in this review.

Molecular markers for Barrett's esophagus and its progression to cancer

PURPOSE OF REVIEW

There is a clinical need for biomarkers that can improve diagnostic accuracy and risk stratification of esophageal lesions. Here we review the current literature and highlight the most important, recent advancements in biomarkers as a supplement to histopathology for management of patients with Barrett's esophagus.

RECENT FINDINGS

A prospective cohort study in Northern Ireland shows that a small panel of biomarkers (low-grade dysplasia, abnormal DNA ploidy and Aspergillus oryzae lectin) can identify patients at high risk for developing high-grade dysplasia or cancer. Recent research in molecular imaging shows promise for molecular probes in endoscopy, using fluorescently labeled peptides or lectins to identify dysplastic areas of Barrett's epithelium. Based on the current literature, p53 immunostaining is starting to be adopted by some centers as an adjunct to histopathology diagnosis for dysplasia.

SUMMARY

The evidence base for the use of biomarkers is increasing and it appears that panels may have superior diagnostic and predictive power over single, candidate biomarkers. Prior to clinical implementation, biomarkers must overcome significant barriers including the need for large-scale prospective validation trials, and the limited ability of clinical laboratories to process and analyze complex biomarker assays.

Optical molecular imaging in the gastrointestinal tract

Recent developments in optical molecular imaging allow for real-time identification of morphologic and biochemical changes in tissue associated with gastrointestinal neoplasia. This review summarizes widefield and high-resolution imaging modalities in preclinical and clinical evaluation for the detection of colorectal cancer and esophageal cancer. Widefield techniques discussed include high-definition white light endoscopy, narrow band imaging, autofluoresence imaging, and chromoendoscopy; high-resolution techniques discussed include probe-based confocal laser endomicroscopy, high-resolution microendoscopy, and optical coherence tomography. New approaches to enhance image contrast using vital dyes and molecular-specific targeted contrast agents are evaluated.

Endocytoscopic visualization of squamous cell islands within Barrett's epithelium

AIM

To study the endocytoscopic visualization of squamous cell islands within Barrett's epithelium.

METHODS

Endocytoscopy (ECS) has been studied in the surveillance of Barrett's esophagus, with controversial results. In initial studies, however, a soft catheter type endocytoscope was used, while only methylene blue dye was used for the staining of Barrett's mucosa. Integrated type endocytoscopes (GIF-Q260 EC, Olympus Corp, Tokyo, Japan) have been recently developed, with the incorporation of a high-power magnifying endocytoscope into a standard endoscope together with narrow-band imaging (NBI). Moreover, double staining with a mixture of 0.05% crystal violet and 0.1% of methylene blue (CM) during ECS enables higher quality images comparable to conventional hematoxylin eosin histopathological images.

RESULTS

In vivo endocytoscopic visualization of papillary squamous cell islands within glandular Barrett's epithelium in a patient with long-segment Barrett's esophagus is reported. Conventional white light endoscopy showed typical long-segment Barrett's esophagus, with small squamous cell islands within normal Barrett's mucosa, which were better visualized by NBI endoscopy. ECS after double CM staining showed regular Barrett's esophagus, while higher magnification (× 480) revealed the orifices of glandular structures better. Furthermore, typical squamous cell papillary protrusion, classified as endocytoscopic atypia classification (ECA) 2 according to ECA, was identified within regular glandular Barrett's mucosa. Histological examination of biopsies taken from the same area showed squamous epithelium within glandular Barrett's mucosa, corresponding well to endocytoscopic findings.

CONCLUSION

To our knowledge, this is the first report of in vivo visualization of esophageal papillary squamous cell islands surrounded by glandular Barrett's epithelium.

Endoscopic Therapy of Neoplasia Related to Barrett's Esophagus and Endoscopic Palliation of Esophageal Cancer

Background

Barrett's esophagus (BE) is the most important identifiable risk factor for the progression to esophageal adenocarcinoma.

Methods

This article reviews the current endoscopic therapies for BE with high-grade dysplasia and intramucosal cancer and briefly discusses the endoscopic palliation of advanced esophageal cancer.

Results

The diagnosis of low-grade or high-grade dysplasia (HGD) is based on several cytologic criteria that suggest neoplastic transformation of the columnar epithelium. HGD and carcinoma in situ are regarded as equivalent. The presence of dysplasia, particularly HGD, is also a risk factor for synchronous and metachronous adenocarcinoma. Dysplasia is a marker of adenocarcinoma and also has been shown to be the preinvasive lesion. Esophagectomy has been the conventional treatment for T1 esophageal cancer and, although debated, is an appropriate option in some patients with HGD due to the presence of occult cancer in over one-third of patients.

Conclusions

Endoscopic ablative modalities (eg, photodynamic therapy and cryoablation) and endoscopic resection techniques (eg, endoscopic mucosal resection) have demonstrated promising results. The significant morbidity and mortality of esophagectomy makes endoscopic treatment an attractive potential option.

Screening and risk stratification for Barrett's esophagus: how to limit the clinical impact of the increasing incidence of esophageal adenocarcinoma

Barrett's esophagus (BE) and gastroesophageal reflux disease are the strongest risk factors for esophageal adenocarcinoma. To reduce the clinical impact of this disease, endoscopic screening to detect BE has been proposed and nonendoscopic diagnostic techniques are under investigation. Because screening would result in new diagnoses of BE and additional costs related to endoscopic surveillance, novel tools for risk stratification are also warranted. Dysplasia is the gold standard for risk stratification. Molecular biomarkers may provide a more objective and reproducible estimation of the individual risk, and further prospective studies are required as a prelude to introducing biomarkers into routine clinical practice.