Barrett's dysplasia and the Vienna classification: reproducibility, prediction of progression and impact of consensus reporting and p53 immunohistochemistry

The Aberrant Expression of Biomarkers and Risk Prediction for Neoplastic Changes in Barrett's Esophagus-Dysplasia

Background: Barrett's esophagus (BE) is a pre-neoplastic condition associated with an increased risk of esophageal adenocarcinoma (EAC). The accurate diagnosis of BE and grading of dysplasia can help to optimize the management of patients with BE. However, BE may be missed and the accurate grading of dysplasia based on a routine histology has a considerable intra- and interobserver variability. Thus, well-defined biomarker testing remains indispensable. The aim of our study was to identify routinely applicable and relatively specific biomarkers for an accurate diagnosis of BE, as well as determining biomarkers to predict the risk of progression in BE-dysplasia. Methods: Retrospectively, we performed immunohistochemistry to test mucin 2(MUC2), trefoil factor 3 (TFF3), p53, p16, cyclin D1, Ki-67, beta-catenin, and minichromosome maintenance (MCM2) in biopsies. Prospectively, to identify chromosomal alterations, we conducted fluorescent in situ hybridization testing on fresh brush samples collected at the time of endoscopy surveillance. Results: We discovered that MUC2 and TFF3 are specific markers for the diagnosis of BE. Aberrant expression, including the loss and strong overexpression of p53, Ki-67, p16, beta-catenin, cyclin D1, and MCM2, was significantly associated with low-grade dysplasia (LGD), high-grade dysplasia (HGD), and EAC histology, with a relatively high risk of neoplastic changes. Furthermore, the aberrant expressions of p53 and p16 in BE-indefinite dysplasia (IND) progressor cohorts predicted the risk of progression. Conclusions: Assessing the biomarkers would be a suitable adjunct to accurate BE histology diagnoses and improve the accuracy of BE-dysplasia grading, thus reducing interobserver variability, particularly of LGD and risk prediction.

Barrett's Esophagus and Associated Dysplasia

Early detection of dysplasia and effective management are critical steps in halting neoplastic progression in patients with Barrett's esophagus (BE). This review provides a contemporary overview of the BE-related dysplasia, its role in guiding surveillance and management, and discusses emerging diagnostic and therapeutic approaches that might further enhance patient management. Novel, noninvasive techniques for sampling and surveillance, adjunct biomarkers for risk assessment, and their limitations are also discussed.

Diagnosis and management of Barrett esophagus: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

MR1 : ESGE recommends the following standards for Barrett esophagus (BE) surveillance:- a minimum of 1-minute inspection time per cm of BE length during a surveillance endoscopy- photodocumentation of landmarks, the BE segment including one picture per cm of BE length, and the esophagogastric junction in retroflexed position, and any visible lesions- use of the Prague and (for visible lesions) Paris classification- collection of biopsies from all visible abnormalities (if present), followed by random four-quadrant biopsies for every 2-cm BE length.Strong recommendation, weak quality of evidence. MR2:  ESGE suggests varying surveillance intervals for different BE lengths. For BE with a maximum extent of ≥ 1 cm and < 3 cm, BE surveillance should be repeated every 5 years. For BE with a maximum extent of ≥ 3 cm and < 10 cm, the interval for endoscopic surveillance should be 3 years. Patients with BE with a maximum extent of ≥ 10 cm should be referred to a BE expert center for surveillance endoscopies. For patients with an irregular Z-line/columnar-lined esophagus of < 1 cm, no routine biopsies or endoscopic surveillance are advised.Weak recommendation, low quality of evidence. MR3:  ESGE suggests that, if a patient has reached 75 years of age at the time of the last surveillance endoscopy and/or the patient's life expectancy is less than 5 years, the discontinuation of further surveillance endoscopies can be considered. Weak recommendation, very low quality of evidence. MR4:  ESGE recommends offering endoscopic eradication therapy using ablation to patients with BE and low grade dysplasia (LGD) on at least two separate endoscopies, both confirmed by a second experienced pathologist.Strong recommendation, high level of evidence. MR5:  ESGE recommends endoscopic ablation treatment for BE with confirmed high grade dysplasia (HGD) without visible lesions, to prevent progression to invasive cancer.Strong recommendation, high level of evidence. MR6:  ESGE recommends offering complete eradication of all remaining Barrett epithelium by ablation after endoscopic resection of visible abnormalities containing any degree of dysplasia or esophageal adenocarcinoma (EAC).Strong recommendation, moderate quality of evidence. MR7:  ESGE recommends endoscopic resection as curative treatment for T1a Barrett's cancer with well/moderate differentiation and no signs of lymphovascular invasion.Strong recommendation, high level of evidence. MR8:  ESGE suggests that low risk submucosal (T1b) EAC (i. e. submucosal invasion depth ≤ 500 µm AND no [lympho]vascular invasion AND no poor tumor differentiation) can be treated by endoscopic resection, provided that adequate follow-up with gastroscopy, endoscopic ultrasound (EUS), and computed tomography (CT)/positrion emission tomography-computed tomography (PET-CT) is performed in expert centers.Weak recommendation, low quality of evidence. MR9:  ESGE suggests that submucosal (T1b) esophageal adenocarcinoma with deep submucosal invasion (tumor invasion > 500 µm into the submucosa), and/or (lympho)vascular invasion, and/or a poor tumor differentiation should be considered high risk. Complete staging and consideration of additional treatments (chemotherapy and/or radiotherapy and/or surgery) or strict endoscopic follow-up should be undertaken on an individual basis in a multidisciplinary discussion.Strong recommendation, low quality of evidence. MR10 A: ESGE recommends that the first endoscopic follow-up after successful endoscopic eradication therapy (EET) of BE is performed in an expert center.Strong recommendation, very low quality of evidence. B:  ESGE recommends careful inspection of the neo-squamocolumnar junction and neo-squamous epithelium with high definition white-light endoscopy and virtual chromoendoscopy during post-EET surveillance, to detect recurrent dysplasia.Strong recommendation, very low level of evidence. C:  ESGE recommends against routine four-quadrant biopsies of neo-squamous epithelium after successful EET of BE.Strong recommendation, low level of evidence. D:  ESGE suggests, after successful EET, obtaining four-quadrant random biopsies just distal to a normal-appearing neo-squamocolumnar junction to detect dysplasia in the absence of visible lesions.Weak recommendation, low level of evidence. E:  ESGE recommends targeted biopsies are obtained where there is a suspicion of recurrent BE in the tubular esophagus, or where there are visible lesions suspicious for dysplasia.Strong recommendation, very low level of evidence. MR11:  After successful EET, ESGE recommends the following surveillance intervals:- For patients with a baseline diagnosis of HGD or EAC:at 1, 2, 3, 4, 5, 7, and 10 years after last treatment, after which surveillance may be stopped.- For patients with a baseline diagnosis of LGD:at 1, 3, and 5 years after last treatment, after which surveillance may be stopped.Strong recommendation, low quality of evidence.

Categorizing Risks within Barrett's Esophagus To Guide Surveillance and Interception; Suggesting a New Framework

Barrett's esophagus is a precancerous condition that can progress in a stepwise manner to dysplasia and eventually esophageal adenocarcinoma (EAC). Once diagnosed, patients with Barrett's esophagus are kept on surveillance to detect progression so that timely intervention can occur with endoscopic therapy. Several demographic and clinical risk factors are known to increase progression toward EAC, such as longer Barrett's segments, and these patients are kept on tighter surveillance. While p53 IHC has been advocated as an adjunct to histopathologic diagnosis, use of this biomarker is variable, and no other molecular factors are currently applied. Given the new evidence available, it is time to consider whether other risk factors or tools could be applied in clinical practice to decide on closer or attenuated surveillance. In this commentary, we summarize the most relevant risk factors for Barrett's esophagus progression, highlight the most promising novel risk stratification tools-including nonendoscopic triage and commercial biomarker panels, and propose a new framework suggesting how to incorporate risk stratification into clinical practice.

Cancer Risk in Barrett's Esophagus: A Clinical Review

Esophageal adenocarcinoma (EAC) is rapidly increasing in incidence and is associated with a poor prognosis. Barrett's esophagus (BE) is a known precursor of esophageal adenocarcinoma. This review aims to explore Barrett's esophagus, esophageal adenocarcinoma, and the progression from the former to the latter. An overview of the definition, diagnosis, epidemiology, and risk factors for both entities are presented, with special attention being given to the areas of debate in the literature. The progression from Barrett's esophagus to esophageal adenocarcinoma is reviewed and the relevant molecular pathways are discussed. The definition of Barrett's esophagus remains debated and without international consensus. This, alongside other factors, has made establishing the true prevalence of Barrett's esophagus challenging. The degree of dysplasia can be a histological challenge, but is necessary to guide clinical management. The progression of BE to EAC is likely driven by inflammatory pathways, pepsin exposure, upregulation of growth factor pathways, and mitochondrial changes. Surveillance is maintained through serial endoscopic evaluation, with shorter intervals recommended for high-risk features.

Defining an abnormal p53 immunohistochemical stain in Barrett's oesophagus-related dysplasia: a single-positive crypt is a sensitive and specific marker of dysplasia

AIMS

p53 is an independent risk stratification marker in Barrett's oesophagus (BE), but no universally accepted definition exists for abnormal p53 staining. Herein, we assess p53 stains in two cohorts to: (1) define abnormal p53 staining in BE-related dysplasia (BERD) and (2) assess the specificity and sensitivity of this cut-point for the diagnosis of dysplasia.

METHODS

Cohort 1 (n = 313) included (1) dysplastic BE biopsies, (2) prior non-dysplastic BE (NDBE) biopsies from the same patients and (3) NDBE biopsies from patients who never progressed to dysplasia. Cohort 2 (n = 191) consisted of BE biopsies in which p53 staining aided in diagnosing dysplasia. Automated p53 staining quantification was performed on cohort 1. A semiquantitative p53 analysis, performed on both cohorts, included: (1) number of strongly positive glands, (2) strong glandular surface staining, (3) percentage of strongly positive glands and (4) null phenotype.

RESULTS

NDBE biopsies from cohort 1 patients who progressed to dysplasia were more likely to show p53 positivity than non-progressors (16.9 versus 0.6%) (P = 0.0001). The optimal quantitative cut-point for distinguishing dysplastic from never-dysplasia biopsies was 10 strongly positive cells. By semiquantitative analysis, a single strongly p53-positive gland distinguished dysplastic from never-dysplasia BE (sensitivity 98.6%, specificity 99.4%). The semiquantitative and quantitative analyses correlated (P = 0.0001). In cohort 2, the sensitivity and specificity for BERD of ≥ 1 strongly positive p53 gland were 86.0 and 88.6%.

CONCLUSIONS

A single strongly positive p53 gland is sensitive and specific for BERD. Automated p53 analysis may reduce subjectivity associated with the diagnosis of BERD.

Development of Advanced Imaging and Molecular Imaging for Barrett's Neoplasia

Barrett esophagus (BE) is a precursor to a life-threatening esophageal adenocarcinoma (EAC). Surveillance endoscopy with random biopsies is recommended for early intervention against EAC, but its adherence in the clinical setting is poor. Dysplastic lesions with flat architecture and patchy distribution in BE are hardly detected by high-resolution endoscopy, and the surveillance protocol entails issues of time and labor and suboptimal interobserver agreement for diagnosing dysplasia. Therefore, the development of advanced imaging technologies is necessary for Barrett's surveillance. Recently, non-endoscopic or endoscopic technologies, such as cytosponge, endocytoscopy, confocal laser endomicroscopy, autofluorescence imaging, and optical coherence tomography/volumetric laser endomicroscopy, were developed, but most of them are not clinically available due to the limited view field, expense of the equipment, and significant time for the learning curve. Another strategy is focused on the development of molecular biomarkers, which are also not ready to use. However, a combination of advanced imaging techniques together with specific biomarkers is expected to identify morphological abnormalities and biological disorders at an early stage in the surveillance. Here, we review recent developments in advanced imaging and molecular imaging for Barrett's neoplasia. Further developments in multiple biomarker panels specific for Barrett's HGD/EAC include wide-field imaging systems for targeting 'red flags', a high-resolution imaging system for optical biopsy, and a computer-aided diagnosis system with artificial intelligence, all of which enable a real-time and accurate diagnosis of dysplastic BE in Barrett's surveillance and provide information for precision medicine.

Endoscopic Diagnosis and Management of Barrett's Esophagus with Low-Grade Dysplasia

Barrett’s Esophagus is a common condition associated with chronic gastroesophageal reflux disease. It is well known that it has an association with a higher incidence of esophageal adenocarcinoma, but this neoplastic transformation is first preceded by the onset of low and high-grade dysplasia. The evaluation of low grade dysplastic esophageal mucosa is still controversial; although endoscopic surveillance is preferred, several minimally invasive endoscopic therapeutic approaches are available. Endoscopic mucosal resection and radiofrequency ablation are the most used endoscopic treatments for the eradication of low-grade dysplasia, respectively, for nodular and flat dysplasia. Novel endoscopic treatments are cryotherapy ablation and argon plasma coagulation, that have good rates of eradication with less complications and post-procedural pain.

Videoconference microscopy is a reliable alternative to conventional microscopy in the evaluation of Barrett's esophagus: Zooming into a new era

Telepathology, practicing pathology from a distance, allows experts to review cases without the need to transfer glass slides. Due to significant intra- and inter-observer variabilities in the histological evaluation of Barrett's esophagus (BE), current guidelines recommend expert consultation in cases of dysplasia. We aimed to determine whether telepathology using microscope videoconferencing can be reliably used for evaluation of BE. Biopsies from 62 patients with endoscopic findings of salmon colored mucosa extending ≥1 cm proximal to the gastroesophageal junction were randomly selected to represent benign esophagus, non-dysplastic BE, low-grade dysplasia, high-grade dysplasia, and adenocarcinoma. Three gastrointestinal-trained pathologists reviewed the cases via videoconference microscopy followed by conventional microscopy. Intra-observer and pairwise inter-observer agreements between the conventional microscopy and videoconference methodologies were calculated for each of the three pathologists using Fleiss-Cohen weighted kappa (K) analysis. The intra-observer agreement for each pathologist's assessment of videoconference microscopy and glass slide readings showed very good reliability (K = 0.94, 95% confidence interval = 0.89-0.99; 0.88, 95% confidence interval = 0.79-0.98; 0.93, 95% confidence interval = 0.90-0.97). Mean pairwise inter-observer agreement was 0.90 for videoconference and 0.91 for conventional microscopy. Diagnosis and grading of BE using videoconference microscopy show similar reliability as conventional microscopy. Based on our findings, we propose that videoconferencing pathology is a valid instrument for evaluating BE.

Utility of ancillary studies in the diagnosis and risk assessment of Barrett's esophagus and dysplasia

Barrett's esophagus (BE) is a major risk factor for the development of esophageal adenocarcinoma (EAC). BE patients undergo periodic endoscopic surveillance with biopsies to detect dysplasia and EAC, but this strategy is imperfect owing to sampling error and inconsistencies in the diagnosis and grading of dysplasia, which may result in an inaccurate diagnosis or risk assessment for progression to EAC. The desire for more accurate diagnosis and better risk stratification has prompted the investigation and development of potential biomarkers that might assist pathologists and clinicians in the management of BE patients, allowing more aggressive endoscopic surveillance and treatment options to be targeted to high-risk individuals, while avoiding frequent surveillance or unnecessary interventions in those at lower risk. It is known that progression of BE to dysplasia and EAC is accompanied by a host of genetic alterations, and that exploration of these markers could be potentially useful to diagnose/grade dysplasia and/or to risk stratify BE patients. Several biomarkers have shown promise in identifying early neoplastic transformation and thus may be useful adjuncts to histologic evaluation. This review provides an overview of some of the currently available biomarkers and assays, including p53 immunostaining, Wide Area Transepithelial Sampling with Three-Dimensional Computer-Assisted Analysis (WATS^3D), TissueCypher, mutational load analysis (BarreGen), fluorescence in situ hybridization, and DNA content abnormalities as detected by DNA flow cytometry.

Barrett's esophagus: The pathomorphological and molecular genetic keystones of neoplastic progression

Barrett's esophagus is a widespread chronically progressing disease of heterogeneous nature. A life threatening complication of this condition is neoplastic transformation, which is often overlooked due to lack of standardized approaches in diagnosis, preventative measures and treatment. In this essay, we aim to stratify existing data to show specific associations between neoplastic transformation and the underlying processes which predate cancerous transition. We discuss pathomorphological, genetic, epigenetic, molecular and immunohistochemical methods related to neoplasia detection on the basis of Barrett's esophagus. Our review sheds light on pathways of such neoplastic progression in the distal esophagus, providing valuable insight into progression assessment, preventative targets and treatment modalities. Our results suggest that molecular, genetic and epigenetic alterations in the esophagus arise earlier than cancerous transformation, meaning the discussed targets can help form preventative strategies in at-risk patient groups.

Barrett's esophagus surveillance in a prospective Dutch multi-center community-based cohort of 985 patients demonstrates low risk of neoplastic progression

Background and Aims

Barrett's esophagus (BE) is accompanied by an increased risk of developing esophageal cancer. Accurate risk‐stratification is warranted to improve endoscopic surveillance. Most data available on risk factors is derived from tertiary care centers or from cohorts with limited surveillance time or surveillance quality. The aim of this study was to assess endoscopic and clinical risk factors for progression to high‐grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) in a large prospective cohort of BE patients from community hospitals supported by an overarching infrastructure to ensure optimal surveillance quality.

Methods

A well‐defined prospective multicenter cohort study was initiated in six community hospitals in the Amsterdam region in 2003. BE patients were identified by PALGA search and included in a prospective surveillance program with a single endoscopist performing all endoscopies at each hospital. Planning and data collection was performed by experienced research nurses who attended all endoscopies. Endpoint was progression to HGD/EAC.

Results

Nine hundred eighty‐five patients were included for analysis. During median follow‐up of 7.9 years (IQR 4.1–12.5) 67 patients were diagnosed with HGD (n = 28) or EAC (n = 39), progression rate 0.78% per patient‐year. As a clinical risk factor age at time of endoscopy was associated with neoplastic progression (HR 1.05; 95% CI 1.03–1.08). Maximum Barrett length and low‐grade dysplasia (LGD) at baseline were endoscopic predictors of progression (HR 1.15; 95% CI 1.09–1.21 and HR 2.36; 95% CI 1.29–4.33).

Conclusion

Risk of progression to HGD/EAC in a large, prospective, community‐based Barrett's cohort was low. Barrett's length, LGD and age were important risk factors for progression.

(www.trialregister.nl NTR1789)

Advances in Biomarkers for Risk Stratification in Barrett's Esophagus

Dysplasia currently is the primary biomarker used to risk stratify patients with Barrett's esophagus, but dysplasia has a number of considerable limitations in this regard. Thus, investigators over the years have explored innumerable alternative molecular biomarkers for risk stratification in Barrett's esophagus. This report focuses only on those biomarkers that appear most promising based on the availability of multiple published studies corroborating good results, and on the commercial availability of the test. These promising biomarkers include p53 immunostaining, TissueCypher, BarreGEN, and wide-area transepithelial sampling with computer-assisted 3-dimensional analysis (WATS^3D).

The modern management of Barrett's oesophagus and related neoplasia: role of pathology

Modern management of Barrett's oesophagus and related neoplasia essentially focuses upon surveillance to detect early low-risk neoplastic lesions and offering organ-preserving advanced endoscopic therapies, while traditional surgical treatments of oesophagectomy and lymph node clearance with or without chemoradiation are preserved only for high-risk and advanced carcinomas. With this evolution towards figless invasive therapy, the choice of therapy hinges upon the pathological assessment for risk stratifying patients into those with low risk for nodal metastasis who can continue with less invasive endoscopic therapies and others with high risk for nodal metastasis for which surgery or other forms of treatment are indicated. Detection and confirmation of neoplasia in the first instance depends upon endoscopic and pathological assessment. Endoscopic examination and biopsy sampling should be performed according to the recommended protocols, and endoscopic biopsy interpretation should be performed applying standard criteria using appropriate ancillary studies by histopathologists experienced in the pathology of Barrett's disease. Endoscopic resections (ERs) are both diagnostic and curative and should be performed by clinicians who are skilled with advanced endoscopic techniques. Proper preparation and handling of ERs are essential to assess histological parameters that dictate the curative nature of the procedure. Those parameters are adequacy of resection and risk of lymph node metastasis. The risk of lymph node metastasis is determined by depth invasion and presence of poor differentiation and lymphovascular invasion. Those adenocarcinomas with invasion up to muscularis mucosae (pT1a) and those with superficial submucosal invasion (pT1b) up to 500 µ with no poor differentiation and lymphovascular invasion and negative margins may be considered cured by endoscopic resections.

Systematic review of the published guidelines on Barrett's esophagus: should we stress the consensus or the differences?

Multiple guidelines on Barrett's esophagus (BE) have being published in order to standardize and improve clinical practice. However, studies have shown poor adherence to them. Our aim was to synthetize, compare, and assess the quality of recommendations from recently published guidelines, stressing similarities and differences. We conducted a search in Pubmed and Scopus. When different guidelines from the same society were identified, the most recent one was considered. We used the GRADE system to assess the quality of evidence. We included 24 guidelines and position/consensus statements from the European Society of Gastrointestinal Endoscopy, British Society of Gastroenterology, American Society for Gastrointestinal Endoscopy, American Gastroenterological Association, American College of Gastroenterology, Australian guidelines, and Asia-Pacific consensus. All guidelines defend that BE should be diagnosed when there is an extension of columnar epithelium into the distal esophagus. However, there is still some controversy regarding length and histology criteria for BE diagnosis. All guidelines recommend expert pathologist review for dysplasia diagnosis. All guidelines recommend surveillance for non-dysplastic BE, and some recommend surveillance for indefinite dysplasia. While the majority of guidelines recommend ablation therapy for low-grade dysplasia without visible lesion, others recommend ablation therapy or endoscopic surveillance. However, controversy exists regarding surveillance intervals and biopsy protocols. All guidelines recommend endoscopic resection followed by ablation therapy for neoplastic visible lesion. Several guidelines use the GRADE system, but the majority of recommendations are based on low and moderate quality of evidence. Although there is considerable consensus among guidelines, there are some discrepancies resulting from low-quality evidence. The lack of high-quality evidence for the majority of recommendations highlights the importance of continued well-conducted research in this field.

Genomic copy number predicts esophageal cancer years before transformation

Recent studies show that aneuploidy and driver gene mutations precede cancer diagnosis by many years^1-4. We assess whether these genomic signals can be used for early detection and pre-emptive cancer treatment using the neoplastic precursor lesion Barrett's esophagus as an exemplar⁵. Shallow whole-genome sequencing of 777 biopsies, sampled from 88 patients in Barrett's esophagus surveillance over a period of up to 15 years, shows that genomic signals can distinguish progressive from stable disease even 10 years before histopathological transformation. These findings are validated on two independent cohorts of 76 and 248 patients. These methods are low-cost and applicable to standard clinical biopsy samples. Compared with current management guidelines based on histopathology and clinical presentation, genomic classification enables earlier treatment for high-risk patients as well as reduction of unnecessary treatment and monitoring for patients who are unlikely to develop cancer.

Gastrointestinal tissue-based molecular biomarkers: a practical categorisation based on the 2019 World Health Organization classification of epithelial digestive tumours

Molecular biomarkers have come to constitute one of the cornerstones of oncological pathology. The method of classification not only directly affects the manner in which patients are diagnosed and treated, but also guides the development of drugs and of artificial intelligence tools. The aim of this article is to organise and update gastrointestinal molecular biomarkers in order to produce an easy-to-use guide for routine diagnostics. For this purpose, we have extracted and reorganised the molecular information on epithelial neoplasms included in the 2019 World Health Organization classification of tumours. Digestive system tumours, 5th edn.

Sporadic adenoma or ulcerative colitis associated neoplasia? The endoscopist's information has an impact on diagnosis and patient management

BACKGROUND

Diagnosing low grade intraepithelial neoplasia (LGIN) in patients with ulcerative colitis (UC) is difficult. Distinguishing between sporadic adenoma (SA) and UC associated LGIN is even more challenging but has clinical impact. We aimed to examine, if the morphological distinction between both entities is reliably possible, how it influences patient's outcome and the role of the endoscopist in this decision with respect to current endoscopy classification schemes.

METHODS

Seven pathologists retrospectively reevaluated 425 cases of LGIN in UC patients, diagnosed between 2009 and 2017 with preceding expert consensus and follow up in two separate readings, based on published morphological differentiation criteria. In the first evaluation, the observers were blinded to any clinical data. In the second evaluation, they knew patients' age as well as endoscopic features. They also rated their subjective diagnostic certainty.

RESULTS

Diagnostic correctness improved significantly in the second assessment as did the pathologists' confidence in their diagnoses (p < 0.001 - p = 0.019). Knowledge of clinical and endoscopical data led to a higher percentage of SA (71.8% vs. 85.6%). UC associated LGIN showed significant earlier LGIN relapse as well as more high grade intraepithelial neoplasia and carcinoma during follow up (p < 0.001, p < 0.001, p = 0.005).

CONCLUSIONS

Distinction between SA and UC associated LGIN is important as it has an impact on patients' follow up and treatment. Morphological distinction remains difficult with moderate interobserver variability. Adequate clinical information significantly improves pathologists' diagnoses as well as their confidence in their diagnoses.

Aneuploidy in targeted endoscopic biopsies outperforms other tissue biomarkers in the prediction of histologic progression of Barrett's oesophagus: A multi-centre prospective cohort study

Background

The cancer risk in Barrett's oesophagus (BO) is difficult to estimate. Histologic dysplasia has strong predictive power, but can be missed by random biopsies. Other clinical parameters have limited utility for risk stratification. We aimed to assess whether a molecular biomarker panel on targeted biopsies can predict neoplastic progression of BO.

Methods

203 patients with BO were tested at index endoscopy for 9 biomarkers (p53 and cyclin A expression; aneuploidy and tetraploidy; CDKN2A (p16), RUNX3 and HPP1 hypermethylation; 9p and 17p loss of heterozygosity) on autofluorescence-targeted biopsies and followed-up prospectively. Data comparing progressors to non-progressors were evaluated by univariate and multivariate analyses using survival curves, Cox-proportional hazards and logistic regression models.

Findings

127 patients without high-grade dysplasia (HGD) or oesophageal adenocarcinoma (OAC) at index endoscopy were included, of which 42 had evidence of any histologic progression over time. Aneuploidy was the only predictor of progression from non-dysplastic BO (NDBO) to any grade of neoplasia (p = 0.013) and HGD/OAC (p = 0.002). Aberrant p53 expression correlated with risk of short-term progression within 12 months, with an odds ratio of 6.0 (95% CI: 3.1–11.2). A panel comprising aneuploidy and p53 had an area under the receiving operator characteristics curve of 0.68 (95% CI: 0.59–0.77) for prediction of any progression.

Interpretation

Aneuploidy is the only biomarker that predicts neoplastic progression of NDBO. Aberrant p53 expression suggests prevalent dysplasia, which might have been missed by random biopsies, and warrants early follow up.

Endoscopic submucosal dissection/endoscopic mucosal resection guidelines for esophageal cancer

The Japan Gastroenterological Endoscopy Society has developed endoscopic submucosal dissection/endoscopic mucosal resection guidelines. These guidelines present recommendations in response to 18 clinical questions concerning the preoperative diagnosis, indications, resection methods, curability assessment, and surveillance of patients undergoing endoscopic resection for esophageal cancers based on a systematic review of the scientific literature.

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.

Challenges to diagnostic standardization of Barrett's esophagus in Asia

Barrett's esophagus (BE), a premalignant condition of the lower esophagus, is increasingly prevalent in Asia. However, endoscopic and histopathological criteria vary widely between studies across Asia, making it challenging to assess comparability between geographical regions. Furthermore, guidelines from various societies worldwide provide differing viewpoints and definitions, leading to diagnostic challenges that affect prognostication of the condition. In this review, the authors discuss the controversies surrounding the diagnosis of BE, particularly in Asia. Differences between guidelines worldwide are summarized with further discussion regarding various classifications of BE used, different definitions of gastroesophageal junction used across geographical regions and the clinical implications of intestinal metaplasia in the setting of BE. Although many guidelines recommend the Seattle protocol as the preferred approach regarding dysplasia surveillance in BE, some limitations exist, leading to poor adherence. Newer technologies, such as acetic acid-enhanced magnification endoscopy, narrow band imaging, Raman spectroscopy, molecular approaches and the use of artificial intelligence appear promising in addressing these problems, but further studies are required before implementation into routine clinical practice. The Asian Barrett's Consortium also outlines its ongoing plans to tackle the challenge of standardizing the diagnosis of BE in Asia.

From genetics to signaling pathways: molecular pathogenesis of esophageal adenocarcinoma

Esophageal adenocarcinoma (EAC) has one of the fastest rising incidence rates in the U.S. and many other Western countries. One of the unique risk factors for EAC is gastroesophageal reflux disease (GERD), a chronic digestive condition in which acidic contents from the stomach, frequently mixed with duodenal bile, enter the esophagus resulting in esophageal tissue injury. At the cellular level, progression to EAC is underlined by continuous DNA damage caused by reflux and chronic inflammatory factors that increase the mutation rate and promote genomic instability. Despite recent successes in cancer diagnostics and treatment, EAC remains a poorly treatable disease. Recent research has shed new light on molecular alterations underlying progression to EAC and revealed novel treatment options. This review focuses on the genetic and molecular studies of EAC. The molecular changes that occur during the transformation of normal Barrett's esophagus to esophageal adenocarcinoma are also discussed.

Improved Progression Prediction in Barrett's Esophagus With Low-grade Dysplasia Using Specific Histologic Criteria

Risk stratification of patients with Barrett's esophagus (BE) is based on diagnosis of low-grade dysplasia (LGD). LGD has a poor interobserver agreement and a limited value for prediction of progression to high-grade dysplasia or esophageal adenocarcinoma. Specific reproducible histologic criteria may improve the predictive value of LGD. Four gastrointestinal pathologists examined 12 histologic criteria associated with LGD in 84 BE patients with LGD (15 progressors and 69 nonprogressors). The criteria with at least a moderate (kappa, 0.4 to 0.6) interobserver agreement were validated in an independent cohort of 98 BE patients with LGD (30 progressors and 68 nonprogressors). Hazard ratios (HR) were calculated by Cox proportional hazard regression analysis using time-dependent covariates correcting for multiple endoscopies during follow-up. Agreement was moderate or good for 4 criteria, that is, loss of maturation, mucin depletion, nuclear enlargement, and increase of mitosis. Combination of the criteria differentiated high-risk and low-risk group amongst patients with LGD diagnosis (P<0.001). When ≥2 criteria were present, a significantly higher progression rate to high-grade dysplasia or esophageal adenocarcinoma was observed (discovery set: HR, 5.47; 95% confidence interval [CI], 1.81-17; P=0.002; validation set: HR, 3.52; 95% CI, 1.56-7.97; P=0.003). Implementation of p53 immunohistochemistry and histologic criteria optimized the prediction of progression (area under the curve, 0.768; 95% CI, 0.656-0.881). We identified and validated a clinically applicable panel of 4 histologic criteria, segregating BE patients with LGD diagnosis into defined prognostic groups. This histologic panel can be used to improve clinical decision making, although additional studies are warranted.

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.

Low-grade dysplasia diagnosis ratio and progression metrics identify variable Barrett's esophagus risk stratification proficiency in independent pathology practices

BACKGROUND AND AIMS

The diagnosis of low-grade dysplasia (LGD) in Barrett's esophagus (BE) is subject to substantial interobserver variation. Our central aim in this study is to compare independent pathology practices using objective measures of BE risk stratification proficiency, including frequency of diagnosis and rate of progression, with high-grade dysplasia (HGD) or adenocarcinoma (EAC) after the first diagnosis of LGD.

METHODS

We retrospectively evaluated over 29,000 endoscopic biopsy cases to identify 4734 patients under endoscopic biopsy surveillance for BE in a healthcare system with multiple independent pathology practices: a subspecialized GI pathology group (SSGI; 162 BE cases per pathologist annually), 3 high BE volume general surgical pathology practices (GSPs; >50 BE cases per pathologist annually), and multiple low BE volume GSPs (10.6 BE cases per pathologist annually). We measured LGD diagnosis frequencies and rates of diagnostic progression to HGD or EAC in patients diagnosed with LGD.

RESULTS

The proportion of all BE cases diagnosed as LGD (LGD/BE diagnosis ratio) ranged from 1.1% to 6.8% in the different hospital settings (P < .001). The cumulative proportion of patients with HGD or EAC within 2 years of the first diagnosis of LGD was 35.3% in the SSGI and ranged from 1.4% to 14.3% in the GSPs (P < .001). LGD diagnosed by the GSP with the lowest LGD/BE diagnosis ratio had an adjusted risk of progression similar to LGD diagnosed by subspecialists (hazard ratio, .42; 95% CI, .06-3.03). However, when LGD was diagnosed by other generalists, the adjusted risk of progression was 79% to 91% lower than subspecialists (P < .001). When LGD was diagnosed in a low-volume GSP practice, the risk of progression was not significantly increased relative to patients with nondysplastic BE (hazard ratio, 1.3; 95% CI, .4-3.9).

CONCLUSIONS

General surgical pathologists and subspecialists show highly significant differences with respect to LGD/BE ratio, risk of progression relative to nondysplastic BE, crude annual progression rates, and the cumulative 2-year progression rate after LGD. These metrics can be used to assess proficiency in BE risk stratification in historical cases. Some general practitioners were able to achieve results similar to subspecialists. General surgical pathologists with little annual experience evaluating BE biopsy specimens did not successfully risk stratify patients with BE.

Molecular Evolution of Metaplasia to Adenocarcinoma in the Esophagus

Esophageal adenocarcinoma (EAC) develops from Barrett's esophagus (BE), a condition where the normal squamous epithelia is replaced by specialized intestinal metaplasia in response to chronic gastroesophageal acid reflux. In a minority of individuals, BE can progress to low- and high-grade dysplasia and eventually to intra-mucosal and then invasive carcinoma. BE provides researchers with a unique model to characterize the process by which a carcinoma arises from its precursor lesion. Molecular studies of BE have demonstrated that it is not simply a metaplastic tissue, but rather it harbors frequent alterations that are also present in dysplastic BE and in EAC. Both BE and EAC are characterized by loss of heterozygosity, aneuploidy, specific genetic mutations, and clonal diversity. Epigenetic abnormalities, primary alterations in DNA methylation, are also frequently seen in BE and EAC. Candidate gene and array-based approaches have demonstrated that numerous tumor suppressor genes exhibit aberrant promoter methylation, and some of these altered genes are associated with the neoplastic progression of BE. It has also been shown that the BE and EAC epigenomes are characterized by hypomethylation of intragenic and non-coding regions Recent studies have also provided new insight into the evolutionary forces underlying the molecular alterations seen in BE and EAC and into the molecular pathogenesis of EAC.

Diagnosis and risk stratification of Barrett's dysplasia by flow cytometric DNA analysis of paraffin-embedded tissue

OBJECTIVE

The diagnosis of dysplasia in Barrett's oesophagus (BO) can be challenging, and reliable ancillary techniques are not available. This study examines if DNA content abnormality detected by flow cytometry can serve as a diagnostic marker of dysplasia and facilitate risk stratification of low-grade dysplasia (LGD) and indefinite for dysplasia (IND) patients using formalin-fixed paraffin-embedded (FFPE) BO samples with varying degrees of dysplasia.

DESIGN

DNA flow cytometry was performed on 80 FFPE BO samples with high-grade dysplasia (HGD), 38 LGD, 21 IND and 14 negative for dysplasia (ND). Three to four 60-micron thick sections were cut from each tissue block, and the area of interest was manually dissected.

RESULTS

DNA content abnormality was identified in 76 HGD (95%), 8 LGD (21.1%), 2 IND (9.5%) and 0 ND samples. As a diagnostic marker of HGD, the estimated sensitivity and specificity of DNA content abnormality were 95% and 85%, respectively. For patients with DNA content abnormality detected at baseline LGD or IND, the univariate HRs for subsequent detection of HGD or oesophageal adenocarcinoma (OAC) were 7.0 and 20.0, respectively (p =<0.001).

CONCLUSIONS

This study demonstrates the promise of DNA flow cytometry using FFPE tissue in the diagnosis and risk stratification of dysplasia in BO. The presence of DNA content abnormality correlates with increasing levels of dysplasia, as 95% of HGD samples showed DNA content abnormality. DNA flow cytometry also identifies a subset of patients with LGD and IND who are at higher risk for subsequent detection of HGD or OAC.

Histological assessment & use of immunohistochemical markers for detection of dysplasia in Barrett's esophageal mucosa

BACKGROUND

Histological assessment of dysplasia in Barrett's esophagus (BE) has high inter-observer variability. Hence, use of ancillary markers for early detection of dysplasia in BE is an important clinical question.

METHODS

In this retrospective study consecutive cases of BE (n = 59), over a period of 4 years were included. Hematoxylin and eosin stained sections were reviewed independently by 3 senior qualified pathologists, who graded the dysplasia according to the Vienna Classification system and inter-observer agreement was analysed using the Kappa statistics. Subsequently Alpha-Methyl Acyl-CoA Racemase (AMACR), p53, CyclinD1, β-catenin, H2AX and M30 immunohistochemical (IHC) stains were examined on the following disease categories: BE with no dysplasia [NFD] (45), BE with indefinite for dysplasia (IFD) (4), low grade dysplasia (LGD) (3), high grade dysplasia (HGD) (2) and in adenocarcinomas (5). H score was calculated by adding up products of different grades of stain distribution and stain intensities (range of scores 0-300).

RESULTS

Among the 3 pathologists, overall agreement was poor (k 0.06; 95% CI -0.089 to 0.145), with highest disagreement noted for differentiating the LGD and IFDs (k = 0.21). After revising the histological criteria, the kappa improved to 0.53. Among the IHC stains performed, p53, β-catenin, H2AX and M30 stains were significantly useful to differentiate between IFD and LGD (P values: 0.04, 0.004, 0.05 & 0.04, respectively). AMACR and β-catenin stains though were up-regulated in HGD/adenocarcinomas than in other categories, their expression were not statistically different between the IFD and LGDs.

CONCLUSIONS

A detail histological scoring system may bring uniformity in histological interpretation of dysplasia in BE. Using a combined panel of IHC stains seems helpful in detection of dysplasia in BE, especially to differentiate the IFD and LGD changes in BE.

Development of benchmark quality criteria for assessing whole-endoscopy Barrett's esophagus biopsy cases

Background

Dysplasia in Barrett's esophagus (BE) biopsies is associated with low observer agreement among general pathologists. Therefore, expert review is advised. We are developing a web-based, national expert review panel for histological review of BE biopsies.

Objective

The aim of this study was to create benchmark quality criteria for future members.

Methods

Five expert BE pathologists, with 10–30 years of BE experience, weekly handling 5–10 cases (25% dysplastic), assessed a case set of 60 digitalized cases, enriched for dysplasia. Each case contained all slides from one endoscopy (non-dysplastic BE (NDBE), n = 21; low-grade dysplasia (LGD), n = 20; high-grade dysplasia (HGD), n = 19). All cases were randomized and assessed twice followed by group discussions to create a consensus diagnosis. Outcome measures: percentage of ‘indefinite for dysplasia’ (IND) diagnoses, intra-observer agreement, and agreement with the consensus ‘gold standard’ diagnosis.

Results

Mean percentage of IND diagnoses was 8% (3–14%) and mean intra-observer agreement was 0.84 (0.66–1.02). Mean agreement with the consensus diagnosis was 90% (95% prediction interval (PI) 82–98%).

Conclusion

Expert pathology review of BE requires the scoring of a limited number of IND cases, consistency of assessment and a high agreement with a consensus gold standard diagnosis. These benchmark quality criteria will be used to assess the performance of other pathologists joining our panel.

Improved diagnostic stratification of digitised Barrett's oesophagus biopsies by p53 immunohistochemical staining

AIMS

Interobserver agreement for dysplasia in Barrett's oesophagus (BO) is low, and guidelines advise expert review of dysplastic cases. The aim of this study was to assess the added value of p53 immunohistochemistry (IHC) for the homogeneity within a group of dedicated gastrointestinal (GI) pathologists.

METHODS AND RESULTS

Sixty-single haematoxylin and eosin (HE) slide referral BO cases [20 low-grade dysplasia (LGD); 20 high-grade dysplasia (HGD); and 20 non-dysplastic BO reference cases] were digitalised and independently assessed twice in random order by 10 dedicated GI pathologists. After a 'wash-out' period, cases were reassessed with the addition of a corresponding p53 IHC slide. Outcomes were: (i) proportion of 'indefinite for dysplasia' (IND) diagnoses; (ii) interobserver agreement; and (iii) diagnostic accuracy as compared with a consensus 'gold standard' diagnosis defined at an earlier stage by five core expert BO pathologists after their assessment of this case set. Addition of p53 IHC decreased the mean proportion of IND diagnoses from 10 of 60 to eight of 60 (P = 0.071). Mean interobserver agreement increased significantly from 0.45 to 0.57 (P = 0.0021). The mean diagnostic accuracy increased significantly from 72% to 82% (P = 0.0072) after p53 IHC addition.

CONCLUSION

Addition of p53 IHC significantly improves the histological assessment of BO biopsies, even within a group of dedicated GI pathologists. It decreases the proportion of IND diagnoses, and increases interobserver agreement and diagnostic accuracy. This justifies the use of accessory p53 IHC within our upcoming national digital review panel for BO biopsy cases.

p53 protein accumulation predicts malignant progression in Barrett's metaplasia: a prospective study of 275 patients

AIMS

The purpose of this study was to determine prospectively whether p53 protein accumulation in biopsies of Barrett's metaplasia (BM) is a predictor of malignant progression, without relying on dysplasia grading.

METHODS AND RESULTS

Sections of formalin-fixed paraffin-embedded tissue from the initial biopsies of 275 patients with BM, who had no high-grade dysplasia (HGD) or oesophageal adenocarcinoma (EAC), were stained for p53 by immunohistochemistry. The mean follow-up was 41 months. p53-positive biopsies were divided into four groups: scattered positive cells, multifocal scattered positive cells, aggregates of positive cells, and multifocal aggregates of positive cells. Kaplan-Meier analysis with the log-rank test was used to determine the rate of progression to HGD/EAC. Of the 275 patients, 227 had initial biopsies that were completely negative for p53, and, of these, one (0.4%) progressed to HGD/EAC; none of 24 (0%) patients with scattered positive cells and none of four (0%) of patients with multifocal scattered positive cells progressed. In contrast, five of 16 (31.25%) patients with aggregates of positive cells and three of four (75%) of those with multifocal aggregates of positive cells progressed to HGD/EAC. Kaplan-Meier analysis with log-rank statistics showed the difference in progression rate between the five groups to be highly significant (P < 0.0001).

CONCLUSIONS

We conclude that p53 protein accumulation, detected by immunohistochemistry in aggregates of cells, is a significant predictor of malignant progression in patients with BM.

Columnar Metaplasia in Three Types of Surgical Mouse Models of Esophageal Reflux

BACKGROUND AND AIMS

Esophageal adenocarcinoma develops in the setting of gastroesophageal reflux and columnar metaplasia in distal esophagus. Columnar metaplasia arising in gastroesophageal reflux models has developed in rat; however, gastroesophageal reflux models in mice have not been well-characterized.

METHODS

One hundred thirty-five C57Bl/6J mice aged 8 weeks old were divided into the following operations: esophagogastrojejunostomy (side-to-side) (EGJ), esophageal separation and esophagojejunostomy (end-to-side) (EJ), and EJ and gastrectomy (end-to-side) (EJ/TG). The animals were euthanized after 40 weeks and the histology of the junction was examined. Immunohistochemistry for p53, PDX-1, and CDX-2 was performed.

RESULTS

Metaplasia developed in 15/33 (45.5%) of EGJ, 0/38 (0%) of EJ, and 6/39 (15.4%) of EJ/TG (P < .05) and dysplasia developed 7/33 (21.2%) of EGJ, 0% of EJ, and 1/39 (2.6%) of EJ/TG. p53 was positive in all of the dysplastic regions, 12/15 (80%) metaplasias in the EGJ model, and 1/6 (16.7%) metaplasia in the EJ/TG model. CDX-2 was positive in all cases of metaplasias, but decreased in some cases of dysplasia. PDX-1 was positive in 7/8 (88%) cases of dysplasia and in 15/21 (71%) cases of metaplasia (P < .05).

CONCLUSIONS

The EGJ model, which causes reflux of gastric acid and duodenal content, developed metaplasia and dysplasia most frequently. No metaplasia developed in the EJ model in which gastric juice and duodenal content mixed before reflux. Thus, duodenal contents alone can induce columnar metaplasia and dysplasia; however, the combination of gastric acid with duodenal content reflux can cause metaplasia and dysplasia more efficiently.

Standardised reporting protocol for endoscopic resection for Barrett oesophagus associated neoplasia: expert consensus recommendations

Endoscopic resection (ER) is considered the therapy of choice for intraepithelial neoplasia associated with visible lesions and T1a adenocarcinoma. Pathologists are bound to encounter specimens collected via these techniques more frequently in their practice. A standardised protocol for handling, grossing, and assessing ER specimens should be adopted to ensure that all prognostic information and characteristics influencing treatment are included in reports (see Supplementary Video Abstract, http://links.lww.com/PAT/A22). The entire specimen should be appropriately oriented, processed and assessed. An ER specimen will commonly show intraepithelial neoplasia or invasive carcinoma. There are essential features that should be recorded if invasive carcinoma is found as they dictate further management and follow-up. These features are the margin status, depth of invasion, degree of differentiation and presence or absence of lymphovascular invasion. Important features such as duplication of muscularis mucosae should be recognised to avoid misinterpretation of depth of invasion. Key diagnostic and prognostic elements that are essential for optimal clinical decisions have been included in the reporting format proposed by the Structured Pathology Reporting committee of the Royal College of Pathologists of Australasia (RCPA).

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.

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.

A preliminary feasibility study: Narrow-band imaging targeted versus standard white light endoscopy non-targeted biopsies in a surveillance Barrett's population

BACKGROUND

Narrow band imaging (NBI) is used in the detection of intestinal metaplasia (IM) and dysplasia in patients with Barrett's oesophagus (BE).

AIMS

The study compared the usefulness of NBI with white-light standard endoscopy (WLSE) for the detection of dysplasia and IM in BE and determined the prediction of the histological diagnosis according to the mucosal and vascular patterns obtained by NBI.

PATIENTS AND METHODS

A total of 84 patients were prospectively enrolled in the study. Every patient underwent a WLSE with random biopsies and after 4-6 weeks, a NBI examination was performed.

RESULTS

NBI detected significant more IM positive biopsies than WLSE (74.5% vs. 35.9%; p<0.0001) and significant more patients with low grade dysplasia (LGD) (7.1% vs. 0%; p=0.03). Taking biopsy samples from the villous pattern determined the diagnosis of IM (80%) and biopsies from the area covered by the irregular pattern lead to the identification of LGD in 45.4% of the cases and indefinite dysplasia (ID) in 18.2% of the cases.

CONCLUSION

A thorough analysis of NBI patterns may lead to real-time IM diagnosis in the absence of the histological examination and may require targeted biopsies from the areas with an irregular pattern for diagnosing dysplasia.

Interobserver variability in intraductal papillary mucinous neoplasm subtypes and application of their mucin immunoprofiles

Intraductal papillary mucinous neoplasm is considered a precursor lesion to pancreatic adenocarcinoma. These are further classified into four histologic subtypes: gastric, intestinal, pancreatobiliary, and oncocytic. The first aim of this study was to assess the interobserver variability among five gastrointestinal pathologists in diagnosing intraductal papillary mucinous neoplasm subtypes by morphology alone. The second aim of the study was to compare intraductal papillary mucinous neoplasm subtypes, which received consensus diagnoses (≥80% agreement) with their respective mucin immunoprofiles (MUC1, MUC2, MUC5AC, MUC6, and CDX2). A consensus histologic subtype was reached in 58% of cases (29/50) among the five gastrointestinal pathologists. Overall there was moderate agreement (κ=0.41, P<0.01) in subtyping intraductal papillary mucinous neoplasms without the use of immunohistochemistry. The histologic subtype with the best interobserver agreement was intestinal type (κ=0.56, P<0.01) followed by pancreatobiliary, gastric, mixed, and oncocytic types (κ=0.43, P<0.01; κ=0.38, P<0.01; κ=0.17, P<0.01; κ=0.08, P<0.04, respectively). Both kappa values for mixed and oncocytic subtypes were likely artificially low due to the underrepresentation of these subtypes in this study and not a true indication of poor interobserver agreement. Following an intradepartmental consensus meeting between two gastrointestinal pathologists, 68% of cases (34/50) received a consensus intraductal papillary mucinous neoplasm subtype. Sixty-nine percent of cases (11/16) that did not receive a consensus intraductal papillary mucinous neoplasm subtype could be classified based on their respective immunoprofiles. Standardizing the use of immunohistochemistry with a mucin immunopanel (MUC1, MUC2, MUC5AC, and MUC6) may improve the agreement of diagnosing intraductal papillary mucinous neoplasm histologic subtypes.

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.

Genetic progression of Barrett's oesophagus to oesophageal adenocarcinoma

Barrett's oesophagus (BE) is the premalignant condition associated with the development of oesophageal adenocarcinoma (OAC). Diagnostically, p53 immunohistochemistry remains the only biomarker recommended clinically to aid histopathological diagnosis. The emerging mutational profile of BE is one of highly heterogeneous lesions at the genomic level with many mutations already occurring in non-dysplastic tissue. As well as point mutations, larger scale copy-number changes appear to have a key role in the progression to OAC and clinically applicable assays for the reliable detection of aneuploidy will be important to incorporate into future clinical management of patients. For some patients, the transition to malignancy may occur rapidly through a genome-doubling event or chromosomal catastrophe, termed chromothripsis, and detecting these patients may prove especially difficult. Given the heterogeneous nature of this disease, sampling methods to overcome inherent bias from endoscopic biopsies coupled with the development of more objective biomarkers than the current reliance on histopathology will be required for risk stratification. The aim of this approach will be to spare low-risk patients unnecessary procedures, as well as to provide endoscopic therapy to the patients at highest risk, thereby avoiding the burden of incurable metastatic disease.

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.

Barrett’s esophagus in 2016: From pathophysiology to treatment

Esophageal complications caused by gastroesophageal reflux disease (GERD) include reflux esophagitis and Barrett’s esophagus (BE). BE is a premalignant condition with an increased risk of developing esophageal adenocarcinoma (EAC). The carcinogenic sequence may progress through several steps, from normal esophageal mucosa through BE to EAC. A recent advent of functional esophageal testing (particularly multichannel intraluminal impedance and pH monitoring) has helped to improve our knowledge about GERD pathophysiology, including its complications. Those findings (when properly confirmed) might help to predict BE neoplastic progression. Over the last few decades, the incidence of EAC has continued to rise in Western populations. However, only a minority of BE patients develop EAC, opening the debate regarding the cost-effectiveness of current screening/surveillance strategies. Thus, major efforts in clinical and research practice are focused on new methods for optimal risk assessment that can stratify BE patients at low or high risk of developing EAC, which should improve the cost effectiveness of screening/surveillance programs and consequently significantly affect health-care costs. Furthermore, the area of BE therapeutic management is rapidly evolving. Endoscopic eradication therapies have been shown to be effective, and new therapeutic options for BE and EAC have emerged. The aim of the present review article is to highlight the status of screening/surveillance programs and the current progress of BE therapy. Moreover, we discuss the recent introduction of novel esophageal pathophysiological exams that have improved the knowledge of the mechanisms linking GERD to BE.