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Aims p53 immunostaining in Barrett's oesophagus ( BO) has been shown to be predictive of progression, but data regarding its generalizability to routine practice are lacking. This study compared the reliability of p53 and dysplasia interpretation and grading. Methods and results Seventy-two cases encompassing the full spectrum of BO were circulated to 10 pathologists from four institutions after a brief training session in p53 interpretation. Each pathologist classified cases on haematoxylin and eosin (H&E) alone using the Vienna classification and assessed the p53 staining using a qualitative system. Agreement was assessed using kappa statistics. For the four-tier Vienna system, the average unweighted kappa was 0.30. Weighted kappa values varied from 0.27 to 0.69 with an average of 0.47. When grouped into definite dysplasia versus no definite dysplasia the average kappa was 0.55, but the kappa for low-grade dysplasia ( LGD) versus high-grade dysplasia ( HGD) was only 0.31. For p53, using the three recognized patterns, the unweighted kappa was 0.6 (confidence interval 0.58-0.63). When cases were evaluated with both H&E and p53 the average kappa was 0.61 for definite dysplasia versus the rest. Conclusions p53 immunohistochemistry interpretation is more reliable than dysplasia diagnosis, even with limited training. As it is predictive of prognosis and improves diagnostic reproducibility, it is suitable for routine use by pathologists as an adjunct to dysplasia diagnosis. The distinction of LGD versus HGD was poor. This study supports simplifying dysplasia diagnosis into 'present', 'indefinite' or 'absent', and the use of p53 as an ancillary marker in difficult cases. This should help to prevent overdiagnosis of dysplasia and inappropriate treatment. [ABSTRACT FROM AUTHOR]

Objective Barrett's oesophagus shows appearances described as 'intestinal metaplasia', in structures called 'crypts' but do not typically display crypt architecture. Here, we investigate their relationship to gastric glands. Methods Cell proliferation and migration within Barrett's glands was assessed by Ki67 and iododeoxyuridine (IdU) labelling. Expression of mucin core proteins (MUC), trefoil family factor (TFF) peptides and LGR5 mRNAwas determined by immunohistochemistry or by in situ hybridisation, and clonality was elucidated using mitochondrial DNA (mtDNA) mutations combined with mucin histochemistry. Results Proliferation predominantly occurs in the middle of Barrett's glands, diminishing towards the surface and the base: IdU dynamics demonstrate bidirectional migration, similar to gastric glands. Distribution of MUC5AC, TFF1, MUC6 and TFF2 in Barrett's mirrors pyloric glands and is preserved in Barrett's dysplasia. MUC2-positive goblet cells are localised above the neck in Barrett's glands, and TFF3 is concentrated in the same region. LGR5 mRNA is detected in the middle of Barrett's glands suggesting a stem cell niche in this locale, similar to that in the gastric pylorus, and distinct from gastric intestinal metaplasia. Gastric and intestinal cell lineages within Barrett's glands are clonal, indicating derivation from a single stem cell. Conclusions Barrett's shows the proliferative and stem cell architecture, and pattern of gene expression of pyloric gastric glands, maintained by stem cells showing gastric and intestinal differentiation: neutral drift may suggest that intestinal differentiation advances with time, a concept critical for the understanding of the origin and development of Barrett's oesophagus. [ABSTRACT FROM AUTHOR]

Background & Aims: The existence of slowly cycling, adult stem cells has been challenged by the identification of actively cycling cells. We investigated the existence of uncommitted, slowly cycling cells by tracking 5-iodo-2''-deoxyuridine (IdU) label-retaining cells (LRCs) in normal esophagus, Barrett''s esophagus (BE), esophageal dysplasia, adenocarcinoma, and healthy stomach tissues from patients. Methods: Four patients (3 undergoing esophagectomy, 1 undergoing esophageal endoscopic mucosal resection for dysplasia and an esophagectomy for esophageal adenocarcinoma) received intravenous infusion of IdU (200 mg/m2 body surface area; maximum dose, 400 mg) over a 30-minute period; the IdU had a circulation half-life of 8 hours. Tissues were collected at 7, 11, 29, and 67 days after infusion, from regions of healthy esophagus, BE, dysplasia, adenocarcinoma, and healthy stomach; they were analyzed by in situ hybridization, flow cytometry, and immunohistochemical analyses. Results: No LRCs were found in dysplasias or adenocarcinomas, but there were significant numbers of LRCs in the base of glands from BE tissue, in the papillae of the basal layer of the esophageal squamous epithelium, and in the neck/isthmus region of healthy stomach. These cells cycled slowly because IdU was retained for at least 67 days and co-labeling with Ki-67 was infrequent. In glands from BE tissues, most cells did not express defensin-5, Muc-2, or chromogranin A, indicating that they were not lineage committed. Some cells labeled for endocrine markers and IdU at 67 days; these cells represented a small population (<0.1%) of epithelial cells at this time point. The epithelial turnover time of the healthy esophageal mucosa was approximately 11 days (twice that of the intestine). Conclusions: LRCs of human esophagus and stomach have many features of stem cells (long lived, slow cycling, uncommitted, and multipotent), and can be found in a recognized stem cell niche. Further analyses of these cells, in healthy and metaplastic epithelia, is required. [Copyright &y& Elsevier]

Background Little is known about the stem cell organisation of the normal oesophagus or Barrett's metaplastic oesophagus. Using non-pathogenic mitochondrial DNA mutations as clonal markers, the authors reveal the stem cell organisation of the human squamous oesophagus and of Barrett's metaplasia and determine the mechanism of clonal expansion of mutations. Methods Mutated cells were identified using enzyme histochemistry to detect activity of cytochrome c oxidase (CCO). CCO-deficient cells were laser-captured and mutations confirmed by PCR sequencing. Cell lineages were identified using immunohistochemistry. Results The normal squamous oesophagus contained CCO-deficient patches varying in size from around 30 mm up to about 1 mm. These patches were clonal as each area within a CCO-deficient patch contained an identical mitochondrial DNA mutation. In Barrett's metaplasia partially CCO-deficient glands indicate that glands are maintained by multiple stem cells. Wholly mutated Barrett's metaplasia glands containing all the expected differentiated cell lineages were seen, demonstrating multilineage differentiation from a clonal population of Barrett's metaplasia stem cells. Patches of clonally mutated Barrett's metaplasia glands were observed, indicating glands can divide to form patches. In one patient, both the regenerating squamous epithelium and the underlying glandular tissue shared a clonal mutation, indicating that they are derived from a common progenitor cell. Conclusion In normal oesophageal squamous epithelium, a single stem cell clone can populate large areas of epithelium. Barrett's metaplasia glands are clonal units, contain multiple multipotential stem cells and most likely divide by fission. Furthermore, a single cell of origin can give rise to both squamous and glandular epithelium suggesting oesophageal plasticity. [ABSTRACT FROM AUTHOR]

Background & Aims: Esophageal adenocarcinoma (EA) is increasingly common among patients with Barrett''s esophagus (BE). We aimed to provide consensus recommendations based on the medical literature that clinicians could use to manage patients with BE and low-grade dysplasia, high-grade dysplasia (HGD), or early-stage EA. Methods: We performed an international, multidisciplinary, systematic, evidence-based review of different management strategies for patients with BE and dysplasia or early-stage EA. We used a Delphi process to develop consensus statements. The results of literature searches were screened using a unique, interactive, Web-based data-sifting platform; we used 11,904 papers to inform the choice of statements selected. An a priori threshold of 80% agreement was used to establish consensus for each statement. Results: Eighty-one of the 91 statements achieved consensus despite generally low quality of evidence, including 8 clinical statements: (1) specimens from endoscopic resection are better than biopsies for staging lesions, (2) it is important to carefully map the size of the dysplastic areas, (3) patients that receive ablative or surgical therapy require endoscopic follow-up, (4) high-resolution endoscopy is necessary for accurate diagnosis, (5) endoscopic therapy for HGD is preferred to surveillance, (6) endoscopic therapy for HGD is preferred to surgery, (7) the combination of endoscopic resection and radiofrequency ablation is the most effective therapy, and (8) after endoscopic removal of lesions from patients with HGD, all areas of BE should be ablated. Conclusions: We developed a data-sifting platform and used the Delphi process to create evidence-based consensus statements for the management of patients with BE and early-stage EA. This approach identified important clinical features of the diseases and areas for future studies. [Copyright &y& Elsevier]

OBJECTIVES: To assess the variation in practice of Barrett's esophagus (BE) management in comparison with accepted international guidelines before and after the introduction of a large BE randomized controlled trial (RCT) with protocols including those of tissue sampling. DESIGN: A validated anonymized questionnaire was sent to 401 senior attending gastroenterologists asking for details of their current management of BE, especially histological sampling. Of the 228 respondents, 57 individuals (each from a different center) were in the first group to enter the ASPirin Esomeprazole (BE) Chemoprevention Trial (AspECT), and we assessed change in practice in these centers. RESULTS: Ninety percent of specialists did not take adequate biopsies for histological diagnosis. Furthermore, 74% would consider aggressive surgical resection for prevalent cases of high-grade dysplasia in BE as their first-line choice despite the associated perioperative mortality. Ninety-two percent claim their lack of adherence to guidelines is because there is a need for stronger evidence for surveillance and medical interventions. Effect of the AspECT trial: Those clinicians in centers where the AspECT trial has started have improved adherence to ACG guidelines compared with their previous practice ( P < 0.05). BE patients now get 18.8% more biopsies compared with previous practice, and 37.7% if the patient is entered into the AspECT trial ( P < 0.01). CONCLUSIONS: This large study indicates both wide variation in practice and poor compliance with guidelines. Because optimal histology is arguably the most important facet of BE management, the improvement in practice in centers taking part in the AspECT trial indicates an additional value of large international RCTs. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Intestinal metaplasia (IM) and dysplasia in Barrett's esophagus are recognized surrogates for esophageal adenocarcinoma risk. While few would argue with the “hunt for dysplasia,” there is a divide regarding the usefulness of the histological confirmation of intestinal metaplasia in endoscopically apparent long segment Barrett's esophagus. We aimed to assess the frequency of intestinal metaplasia in 125 consecutive patients with columnar-lined esophagus and to determine the optimal biopsy protocol to detect intestinal metaplasia. METHODS: Two-hundred ninety-six endoscopies were performed over a 4-yr period in Barrett's esophagus segments of mean length 4 cm (range 1–11 cm) at a single center and the resulting biopsies were analyzed retrospectively. Biopsies were all processed with routine hematoxylin and eosin (H&E) staining, and a subset (N = 92) was subject to alcian blue/periodic-acid Schiff staining. RESULTS: Using H&E staining, we found that the optimum number of biopsies to diagnose intestinal metaplasia was 8 per endoscopy, mean 67.9% endoscopies having intestinal metaplasia. In contrast, if only four were taken the yield was 34.7% with intestinal metaplasia. Unless more than 16 biopsies were taken (100% yield of intestinal metaplasia), no additional significant detection was achieved. Using additional alcian blue/periodic-acid Schiff staining only had a marginal benefit, with 5.4% of new cases of intestinal metaplasia being identified. There is a proximal cephalo-caudal gradient of intestinal metaplasia, especially with increased chronological age, but doing repeat endoscopies on patients did not increase the detection of intestinal metaplasia. CONCLUSIONS: The data suggest that at least 8 random biopsies is the minimum to be taken and analyzed with conventional H&E staining to diagnose benign intestinal metaplasia. Taking more biopsies did not statistically increase the diagnosis of intestinal metaplasia except when greater than 16 were taken when 100% yield was obtained. [ABSTRACT FROM AUTHOR]