Barrett's esophagus and Barrett's-related dysplasia

Aberrant p53 expression is associated with neoplastic progression in Barrett oesophagus diagnosed as indefinite for dysplasia

The aim of this study was to investigate the role of immunohistochemical (IHC) expression of p53 and other potential clinical parameters as prognostic markers for predicting neoplastic progression in Barrett oesophagus (BE) patients diagnosed as indefinite for dysplasia (IND). The study included patients with established BE of any extent who had a diagnosis of IND accompanied by concurrent p53 immunohistochemistry (IHC) stain at the index endoscopic procedure and at least one follow-up examination between 2000 and 2021. Correlation between disease progression from IND to higher-grade dysplasia [low-grade dysplasia (LGD), high-grade dysplasia (HGD) and oesophageal adenocarcinoma (EAC)] and clinicopathological parameters were analysed. A total of 149 patients (99 males; mean age 63.3 ± 10.0 years, range = 35-89) were included in the final analysis. Median follow-up was 37.1 months [interquartile range (IQR) = 20.5-59.1 months]. Progression rates from IND to LGD and HGD were 12.1% (18 of 149) and 2.7% (four of 149), respectively. On multivariate analysis, the number of IND diagnoses was significantly associated with progression to both LGD and HGD (P = 0.016 and P < 0.001, respectively). Cox regression analysis showed that aberrant p53 expression was significantly associated with progression to LGD [hazard ratio (HR) = 4.87, 95% confidence interval (CI) = 1.91-12.45, P = 0.001] and HGD (HR = 21.81, 95% CI = 1.88-253.70, P = 0.014). Kaplan-Meier survival analysis also demonstrated that aberrant p53 expression was significantly associated with progression to LGD (P < 0.001) and HGD (P = 0.001). Our results suggest that frequency of IND diagnoses and status of p53 expression can help to stratify risk of neoplastic progression in BE patients with IND.

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.

AI-assisted discovery of an ethnicity-influenced driver of cell transformation in esophageal and gastroesophageal junction adenocarcinomas

Although Barrett's metaplasia of the esophagus (BE) is the only known precursor lesion to esophageal adenocarcinomas (EACs), drivers of cellular transformation in BE remain incompletely understood. We use an artificial intelligence-guided network approach to study EAC initiation and progression. Key predictions are subsequently validated in a human organoid model, in patient-derived biopsy specimens of BE, a case-control study of genomics of BE progression, and in a cross-sectional study of 113 patients with BE and EACs. Our model classified healthy esophagus from BE and BE from EACs in several publicly available gene expression data sets (n = 932 samples). The model confirmed that all EACs must originate from BE and pinpointed a CXCL8/IL8↔neutrophil immune microenvironment as a driver of cellular transformation in EACs and gastroesophageal junction adenocarcinomas. This driver is prominent in White individuals but is notably absent in African Americans (AAs). Network-derived gene signatures, independent signatures of neutrophil processes, CXCL8/IL8 expression, and an absolute neutrophil count (ANC) are associated with risk of progression. SNPs associated with changes in ANC by ethnicity (e.g., benign ethnic neutropenia [BEN]) modify that risk. Findings define a racially influenced immunological basis for cell transformation and suggest that BEN in AAs may be a deterrent to BE→EAC progression.

Wide-area transepithelial sampling for dysplasia detection in Barrett's esophagus: a systematic review and meta-analysis

BACKGROUND AND AIMS

Seattle protocol forceps biopsy sampling (FB) is currently recommended for surveillance in Barrett's esophagus (BE) but limited by sampling error and lack of compliance. Wide-area transepithelial sampling with 3-dimensional analysis (WATS3D; CDx Diagnostics, Suffern, NY, USA) is reported to increase BE dysplasia detection. We assessed the incremental yield and clinical significance of WATS3D for dysplasia detection over FB in a systematic review and meta-analysis.

METHODS

We queried major scientific databases for studies using WATS3D and FB from 2000 to 2020. The primary outcome was the incremental yield of WATS3D-detected dysplasia (defined as a composite of indefinite for dysplasia, low- and high-grade dysplasia [HGD] and esophageal adenocarcinoma [EAC]) over FB. Secondary outcomes were incremental yields of HGD/EAC and rate of reconfirmation of WATS3D dysplasia on subsequent FB.

RESULTS

Meta-analysis of 7 eligible studies demonstrated that FB diagnosed dysplasia in 15.9% of cases, whereas the incremental yield with WATS3D was 7.2% (95% confidence interval, 3.9%-11.5%; I²= 92.1%). Meta-analysis of 6 studies demonstrated that FB diagnosed HGD/EAC in 2.3% of patients, whereas the incremental yield with WATS3D was 2.1% (95% confidence interval, .4%-5.3%; I²= 92.7%). Notably, WATS3D was negative in 62.5% of cases where FB identified dysplasia. Two studies reported reconfirmation of WATS3D dysplasia with FB histology in only 20 patients.

CONCLUSIONS

WATS3D increases dysplasia detection; however, the clinical significance of this increased dysplasia detection remains uncertain. Data from endoscopic follow-up to ascertain FB histology in patients with dysplasia based solely on WATS3D are needed to determine the optimal clinical application and significance of WATS3D-only dysplasia.

Forkhead box F1 induces columnar phenotype and epithelial-to-mesenchymal transition in esophageal squamous cells to initiate Barrett's like metaplasia

Multiple genome-wide association studies (GWAS) have linked Forkhead Box F1 (FOXF1) to Barrett's esophagus (BE). Understanding whether FOXF1 is involved in initiation of Barrett's metaplasia could allow FOXF1 to be used for risk stratification and for therapy. Two-dimensional cell cultures and three-dimensional organoid cultures and well-annotated human biopsies were used to determine the role of FOXF1 in BE pathogenesis. Multiple established esophageal squamous and BE cell lines were tested in gain- and loss-of-function studies. Initiation of a BE-like metaplastic change was evaluated by measuring characteristic cytokeratins and global gene expression profiling and by culturing organoids. Epithelial-mesenchymal transition (EMT) was evaluated by immunostaining for E-cadherin, vimentin and Snail, and by cell motility assay. Columnar esophageal epithelium of BE patients exhibited higher expression of FOXF1 compared to normal squamous esophageal epithelium of GERD patients (P < 0.001). Acidic bile salts induced nuclear FOXF1 in esophageal squamous cells. FOXF1 overexpression in normal esophageal squamous cells: (a) increased columnar cytokeratins and decreased squamous cytokeratins, (b) converted squamous organoids to glandular organoids, and (c) switched global gene profiles to resemble that of human BE epithelium (P = 2.1685e - 06 for upregulated genes and P = 8.3378e - 09 for downregulated genes). FOXF1 inhibition in BE cell lines led to loss of BE differentiation markers, CK7, and mucin 2. Also, FOXF1 induced EMT and promoted cell motility in normal esophageal squamous epithelial cells. FOXF1-induced genes mapped to pathways such as Cancer, Cellular Assembly and Organization, DNA Replication, Recombination, and Repair. In conclusion, FOXF1 promotes a BE-like columnar phenotype and cell motility in esophageal squamous epithelial cells, which may have a critical role in BE development. FOXF1 should be studied further as a biomarker for BE and as a target for BE treatment.

Optical Biopsy of the Upper GI Tract Using Fluorescence Lifetime and Spectra

Screening and surveillance for gastrointestinal (GI) cancers by endoscope guided biopsy is invasive, time consuming, and has the potential for sampling error. Tissue endogenous fluorescence spectra contain biochemical and physiological information, which may enable real-time, objective diagnosis. We first briefly reviewed optical biopsy modalities for GI cancer diagnosis with a focus on fluorescence-based techniques. In an ex vivo pilot clinical study, we measured fluorescence spectra and lifetime on fresh biopsy specimens obtained during routine upper GI screening procedures. Our results demonstrated the feasibility of rapid acquisition of time-resolved fluorescence (TRF) spectra from fresh GI mucosal specimens. We also identified spectroscopic signatures that can differentiate between normal mucosal samples obtained from the esophagus, stomach, and duodenum.

Evaluation of Serum Glycoprotein Biomarker Candidates for Detection of Esophageal Adenocarcinoma and Surveillance of Barrett's Esophagus

Esophageal adenocarcinoma (EAC) is thought to develop from asymptomatic Barrett's esophagus (BE) with a low annual rate of conversion. Current endoscopy surveillance of BE patients is probably not cost-effective. Previously, we discovered serum glycoprotein biomarker candidates which could discriminate BE patients from EAC. Here, we aimed to validate candidate serum glycoprotein biomarkers in independent cohorts, and to develop a biomarker candidate panel for BE surveillance. Serum glycoprotein biomarker candidates were measured in 301 serum samples collected from Australia (4 states) and the United States (1 clinic) using previously established lectin magnetic bead array (LeMBA) coupled multiple reaction monitoring mass spectrometry (MRM-MS) tier 3 assay. The area under receiver operating characteristic curve (AUROC) was calculated as a measure of discrimination, and multivariate recursive partitioning was used to formulate a multi-marker panel for BE surveillance. Complement C9 (C9), gelsolin (GSN), serum paraoxonase/arylesterase 1 (PON1) and serum paraoxonase/lactonase 3 (PON3) were validated as diagnostic glycoprotein biomarkers in lectin pull-down samples for EAC across both cohorts. A panel of 10 serum glycoprotein biomarker candidates discriminated BE patients not requiring intervention (BE± low grade dysplasia) from those requiring intervention (BE with high grade dysplasia (BE-HGD) or EAC) with an AUROC value of 0.93. Tissue expression of C9 was found to be induced in BE, dysplastic BE and EAC. In longitudinal samples from subjects that have progressed toward EAC, levels of serum C9 were significantly (p < 0.05) increased with disease progression in EPHA (erythroagglutinin from Phaseolus vulgaris) and NPL (Narcissus pseudonarcissus lectin) pull-down samples. The results confirm alteration of complement pathway glycoproteins during BE-EAC pathogenesis. Further prospective clinical validation of the confirmed biomarker candidates in a large cohort is warranted, prior to development of a first-line BE surveillance blood test.

Digital microscopy as valid alternative to conventional microscopy for histological evaluation of Barrett's esophagus biopsies

Management of Barrett's esophagus (BE) relies heavily on histopathological assessment of biopsies, associated with significant intra- and interobserver variability. Guidelines recommend biopsy review by an expert in case of dysplasia. Conventional review of biopsies, however, is impractical and does not allow for teleconferencing or annotations. An expert digital review platform might overcome these limitations. We compared diagnostic agreement of digital and conventional microscopy for diagnosing BE ± dysplasia. Sixty BE biopsy glass slides (non-dysplastic BE (NDBE); n = 25, low-grade dysplasia (LGD); n = 20; high-grade dysplasia (HGD); n = 15) were scanned at ×20 magnification. The slides were assessed four times by five expert BE pathologists, all practicing histopathologists (range: 5-30 years), in 2 alternating rounds of digital and conventional microscopy, each in randomized order and sequence of slides. Intraobserver and pairwise interobserver agreement were calculated, using custom weighted Cohen's kappa, adjusted for the maximum possible kappa scores. Split into three categories (NDBE, IND, LGD+HGD), the mean intraobserver agreement was 0.75 and 0.84 for digital and conventional assessment, respectively (p = 0.35). Mean pairwise interobserver agreement was 0.80 for digital and 0.85 for conventional microscopy (p = 0.17). In 47/60 (78%) of digital microscopy reviews a majority vote of ≥3 pathologists was reached before consensus meeting. After group discussion, a majority vote was achieved in all cases (60/60). Diagnostic agreement of digital microscopy is comparable to that of conventional microscopy. These outcomes justify the use of digital slides in a nationwide, web-based BE revision platform in the Netherlands. This will overcome the practical issues associated with conventional histologic review by multiple pathologists.

FABP1 and Hepar expression levels in Barrett's esophagus and associated neoplasia in an Asian population

INTRODUCTION

Barrett's esophagus (BE) is a premalignant condition associated with esophageal adenocarcinoma (EAC). Evidence highlights that EAC is associated with an estimated 5-year survival of approximately 10-15%. Therefore, there is a need to determine which biomarkers are of value in the diagnosis of BE and beyond. The aim of our study was to evaluate the clinical significance of markers known to be expressed across BE and associated neoplasia.

METHODS

Retrospective tissues were obtained from columnar lined esophagus (CLE) without goblet cells (n=22), BE (n=29), dysplasia (n=14), and EAC (n=10). Standardised immunohistochemistry for FABP1, Hepar, CDH17, and CDX2 were performed followed by quantitative staining and statistical analysis.

RESULTS

FABP1 expression was negligible in CLE and was highest in BE, with a further decrease in expression in dysplasia and EAC. Hepar expression was also negligible in CLE and was highest in dysplasia and BE, with a reduced expression in EAC. CDH17 and CDX2 showed a significantly higher expression in BE, dysplasia, and EAC compared to CLE.

CONCLUSION

All 4 markers were excellent diagnostic panels to clearly discriminate BE from CLE. Moreover, as FABP1 and Hepar have different expression levels in dysplasia and EAC, these markers could function as key diagnostic aids in helping to determine the state of disease progression.

[Differentiation therapy for non-acidic gastroesophageal reflux disease]

AIM

To investigate the clinical and pathogenetic features of the non-acidic types of gastroesophageal reflux disease (GERD) and to evaluate the impact of combined therapy versus monotherapy on the course of this disease.

SUBJECTS AND METHODS

The investigation enrolled 62 patients with non-acidic GERD. The follow-up period was 6 weeks. The patients were divided into 2 groups: 1) weakly acidic gastroesophageal refluxes (GER); 2) weakly alkaline GER. Then each group was distributed, thus making up 4 groups: 1) 19 patients with weakly acidic GER who received monotherapy with rabeprazole 20 mg/day; 2) 21 patients with weakly acidic GER had combined therapy with rabeprazole 20 mg and itopride; 3) 8 patients with weakly alkaline GER who received ursodeoxycholic acid (UDCA) monotherapy; and 4) 14 patients with weakly alkaline GER who had combined therapy with UDCA and itopride, The clinical symptoms of the disease, the endoscopic pattern of the upper gastrointestinal tract (GIT) mucosa, histological changes in the esophageal and gastric mucosa, and the results of 24-hour impedance pH monitoring were assessed over time.

RESULTS

During differentiation therapy, the majority of patients reported positive clinical changes and an improved or unchanged endoscopic pattern. Assessment of impedance pH monitoring results revealed decreases in the overall number of GERs, the presence of a bolus in the esophagus, and the number of proximal refluxes. These changes were noted not only in patients taking proton pump inhibitors (PPIs), but also in those treated with UDCA monotherapy or combined PPI and prokinetic therapy.

CONCLUSION

A differentiated approach to non-acidic GER treatment contributes to its efficiency. Adding the prokinetic itomed (itopride hydrochloride) to PPI therapy in a patient with weakly acidic GER enhances the efficiency of treatment, by positively affecting upper GIT motility. The mainstay of therapy for GERD with a predominance of weakly alkaline refluxes is UDCA, the combination of the latter and the prokinetic can exert a more pronounced effect on the clinical and endoscopic pattern and upper GIT motility.

The surgical management of esophago-gastric junctional cancer

The best available surgical strategy in the treatment of resectable esophago-gastric junctional (EGJ) cancer is a controversial topic. In this review we evaluate the current literature and scientific evidence examining the surgical treatment of locally advanced EGJ cancer by comparing esophagectomy with gastrectomy, transhiatal with transthoracic esophagectomy, minimally invasive with open esophagectomy, and less extensive with more extensive lymphadenectomy. We also assess endoscopic procedures increasingly used for early EGJ cancer. The current evidence does not favor any of the techniques over the others in terms of oncological outcomes. Health-related quality of life may be better following gastrectomy compared to esophagectomy. Minimally invasive procedures might be less prone to surgical complications. Endoscopic techniques are safe and effective alternatives for early-stage EGJ cancer in the short term, but surgical treatment is the mainstay in fit patients due to the risk of lymph node metastasis. Any benefit of lymphadenectomy extending beyond local or regional nodes is uncertain. This review demonstrates the great need for well-designed clinical studies to improve the knowledge in how to optimize and standardize the surgical treatment of EGJ cancer.

Surgical and Molecular Pathology of Barrett Esophagus

BACKGROUND

Patients with Barrett esophagus (BE) are predisposed to developing dysplasia and cancer. Adenocarcinoma, which is associated with BE, is the most common type of esophageal tumor and, typically, it has an aggressive clinical course and a high rate of mortality.

METHODS

The English-language literature relating to tumor epidemiology, etiology, and the pathogenesis of BE was reviewed and summarized.

RESULTS

The role of pathologists in the diagnosis and pitfalls associated with grading Barrett dysplasia is addressed. Current molecular testing for Barrett neoplasia, as well as testing methods currently in development, is discussed, focusing on relevant tests for diagnosing tumor types, determining prognosis, and assessing therapeutic response.

CONCLUSIONS

Grading is essential for developing appropriate treatment plans, follow-up visits, and therapeutic interventions for each patient. Familiarity with current molecular testing methods will help physicians correctly diagnose the disease and select the most appropriate therapy for each of their patients.

Discrete Element Framework for Modelling Extracellular Matrix, Deformable Cells and Subcellular Components

This paper presents a framework for modelling biological tissues based on discrete particles. Cell components (e.g. cell membranes, cell cytoskeleton, cell nucleus) and extracellular matrix (e.g. collagen) are represented using collections of particles. Simple particle to particle interaction laws are used to simulate and control complex physical interaction types (e.g. cell-cell adhesion via cadherins, integrin basement membrane attachment, cytoskeletal mechanical properties). Particles may be given the capacity to change their properties and behaviours in response to changes in the cellular microenvironment (e.g., in response to cell-cell signalling or mechanical loadings). Each particle is in effect an ‘agent’, meaning that the agent can sense local environmental information and respond according to pre-determined or stochastic events. The behaviour of the proposed framework is exemplified through several biological problems of ongoing interest. These examples illustrate how the modelling framework allows enormous flexibility for representing the mechanical behaviour of different tissues, and we argue this is a more intuitive approach than perhaps offered by traditional continuum methods. Because of this flexibility, we believe the discrete modelling framework provides an avenue for biologists and bioengineers to explore the behaviour of tissue systems in a computational laboratory.

Modelling is an important tool in understanding the behaviour of biological tissues. In this paper we advocate a new modelling framework in which cells and tissues are represented by a collection of particles with associated properties. The particles interact with each other and can change their behaviour in response to changes in their environment. We demonstrate how the propose framework can be used to represent the mechanical behaviour of different tissues with much greater flexibility as compared to traditional continuum based methods.

Barrett oesophagus: lessons on its origins from the lesion itself

Barrett oesophagus develops when the lower oesophageal squamous epithelium is replaced with columnar epithelium, which shows both intestinal and gastric differentiation. No consensus has been reached on the origin of Barrett oesophagus. Theories include a direct origin from the oesophageal-stratified squamous epithelium, or by proximal migration of the gastric cardiac epithelium with subsequent intestinalization. Variations of this theory suggest the origin is a distinctive cell at the squamocolumnar junction, the oesophageal gland ducts, or circulating bone-marrow-derived cells. Much of the supporting evidence comes from experimental models and not from studies of Barrett mucosa. In this Perspectives article, we look at the Barrett lesion itself: at its phenotype, its complexity, its clonal architecture and its stem cell organization. We conclude that Barrett glands are unique structures, but share many similarities with gastric glands undergoing the process of intestinal metaplasia. We conclude that current evidence most strongly supports an origin from stem cells in the cardia.

Endoscopic management of Barrett's esophagus with high-grade dysplasia and early-stage esophageal adenocarcinoma

Several endoscopic procedures have been recently developed for the treatment of Barrett's esophagus and early esophageal cancer, including endoscopic resection, radiofrequency ablation, and cryoablation. This review article discusses ideal candidates for endoscopic therapies, current treatment modalities, clinical and safety outcomes, and specific management recommendations.

Management of early-stage esophageal neoplasia (MESEN) consensus

BACKGROUND

Treatment of esophageal adenocarcinoma often involves surgical resection. Newer technologies in interventional endoscopy have led to a substantial paradigm shift in the management of early-stage neoplasia in Barrett's esophagus comprising high-grade dysplasia (HGD), intramucosal carcinoma, and, in some cases, submucosal carcinoma. However, there has been no consensus regarding the indications for esophageal preservation in these cases. In this work, consensus guidelines were established for the management of early-stage esophageal neoplasia considering clinically relevant aspects (age, comorbidities, and social environment) in each scenario.

METHODS

Seventeen experts were invited to participate based on their background and clinical expertise at high-volume centers. A questionnaire was created that included four clinical scenarios covering a wide range of situations within HGD and/or early esophageal neoplasia, particularly where controversies are likely to exist. Each of the clinical scenarios was open to discussion subdivided by patient age (20, 50, and 80 s). For each clinical scenario an expert was chosen to defend that position. Each defense triggered a subsequent discussion during a consensus meeting. Conclusions of that discussion together with an accompanying literature analysis allowed experts to confirm or change their original choices and served as the basis for the recommendations stated in this article.

RESULTS

There was 100 % consensus supporting esophageal preservation in patients with HGD, independent of patient age or Barrett's length. In patients with T1a adenocarcinoma, consensus for preservation was not reached (65 %) for young and middle-aged individuals but was supported for elderly patients (100 %). For T1b adenocarcinoma, consensus was reached for surgical resection (90 %), leaving organ preservation for patients with very low risk of nodal invasion or poor surgical candidates.

CONCLUSION

Advances in endoscopic imaging and therapy allow for organ preservation in most settings of early-stage neoplasia of the esophagus, provided that the patient understands the implications of this decision.

GERD-Barrett-Adenocarcinoma: Do We Have Suitable Prognostic and Predictive Molecular Markers?

Due to unfavorable lifestyle habits (unhealthy diet and tobacco abuse) the incidence of gastroesophageal reflux disease (GERD) in western countries is increasing. The GERD-Barrett-Adenocarcinoma sequence currently lacks well-defined diagnostic, progressive, predictive, and prognostic biomarkers (i) providing an appropriate screening method identifying the presence of the disease, (ii) estimating the risk of evolving cancer, that is, the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EAC), (iii) predicting the response to therapy, and (iv) indicating an overall survival—prognosis for EAC patients. Based on histomorphological findings, detailed screening and therapeutic guidelines have been elaborated, although epidemiological studies could not support the postulated increasing progression rates of GERD to BE and EAC. Additionally, proposed predictive and prognostic markers are rather heterogeneous by nature, lack substantial proofs, and currently do not allow stratification of GERD patients for progression, outcome, and therapeutic effectiveness in clinical practice. The aim of this paper is to discuss the current knowledge regarding the GERD-BE-EAC sequence mainly focusing on the disputable and ambiguous status of proposed biomarkers to identify promising and reliable markers in order to provide more detailed insights into pathophysiological mechanisms and thus to improve prognostic and predictive therapeutic approaches.

Synthesis and characterization of anti-EGFR fluorescent nanoparticles for optical molecular imaging

Molecular imaging, the visualization of molecular and cellular markers, is a promising method for detection of dysplasia and early cancer in the esophagus and can potentially be used to identify regions of interest for biopsy or tumor margins for resection. EGFR is a previously reported cell surface receptor with stepwise increases in expression during the progression from Barrett's metaplasia to adenocarcinoma. In this work, a 200 nm fluorescent nanoparticle contrast agent was synthesized for targeted imaging of EGFR through a series of surface modifications to dye-encapsulated polystyrene particles. Amino-functionalized polystyrene particles were PEGylated using a heterobifunctional PEG linker. Subsequently, thiolated M225 antibodies were conjugated to maleimide functional groups on attached PEGs for EGFR targeting. In vitro binding studies using flow cytometry demonstrated specific binding of M225-PEG-NP to EGFR-expressing cells with minimal nonspecific binding in EGFR(-) cells. Binding was shown to increase proportionally with the number of conjugated M225 antibodies. Adsorbed formulations with unmodified M225 antibodies, M225 + PEG-NP, were synthesized using the same antibody feeds used in M225-PEG-NP synthesis to determine the contribution of adsorbed antibodies to EGFR targeting. Adsorbed antibodies were less efficient at mediated nanoparticle targeting to EGFR than conjugated antibodies. Finally, M225-PEG-NP demonstrated binding to EGFR-expressing regions in human esophageal tissue sections.

Endoscopic therapy of Barrett esophagus

Barrett esophagus (BE) is a well-established premalignant condition for esophageal adenocarcinoma (EAC), a lethal cancer with a dismal survival rate. The current guidelines recommend surveillance of patients with BE to detect dysplasia or early cancer before the development of invasive EAC. Recently, endoscopic eradication therapies have been shown to be safe and effective in the treatment of BE-related high-grade dysplasia and early EAC. This article reviews the various treatment options for BE and discusses the current evidence and gaps in knowledge in the understanding of treatment of this condition. In addition, recommendations are provided in context to the recently published guidelines by the American Gastroenterological Association.

An analysis of esophagectomy and other techniques in the management of high-grade dysplasia of Barrett's esophagus

Barrett's esophageal (BE) metaplasia is a premalignant condition of the distal esophagus that develops as a consequence of gastroesophageal reflux disease. The progression to carcinogenesis results from progressive dysplastic changes of the metaplastic epithelium through low-grade and then high-grade dysplasia (HGD) to eventually adenocarcinoma of the esophagus. The management of HGD is controversial with proponents for each of the three major management strategies: endoscopic surveillance, endoscopic ablative therapies, and esophagectomy. The aim of the study was to define and discuss the various management strategies of HGD arising from BE metaplasia. There is a paucity of randomized controlled data from which to draw definitive conclusions. All strategies for the management of HGD are reasonable options and are complimentary. BE with HGD is a malignant lesion. A multidisciplinary approach individualizing therapy should be undertaken when possible. Esophageal resection should be reserved for otherwise healthy patients. Endoscopic techniques are viable alternatives to surgery.

Endoscopic therapies for the prevention and treatment of early esophageal neoplasia

Esophageal cancers have traditionally been diagnosed late and prognosis has been dire. For many years the only real treatment option was esophagectomy with substantial morbidity and mortality. This situation has now changed dramatically. Improvements have been achieved in surgical outcomes and there is an array of new effective treatment options now available, particularly for the increasing proportion diagnosed with early-stage disease. Minimally invasive endoscopic therapies can now prevent, cure or palliate esophageal cancers. This article aims to investigate the role and evidence base for these new therapeutic options.

State of the art in the endoscopic imaging and ablation of Barrett's esophagus

Barrett's esophagus is the result of long-term acid reflux and is a precursor to esophageal adenocarcinoma. Surgical resection of the esophagus has been the mainstay of treatment for high grade dysplasia and early cancer. However, recent advances in the endoscopic imaging and ablation technologies have made esophagectomy avoidable in patients with dysplasia and superficial neoplasia. In this article, we review the most relevant endoscopic imaging technologies, such as chromoendoscopy, narrow band and autofluorescence imaging, and confocal laser endomicroscopy. We also review the various endoscopic ablation technologies, such as endoscopic mucosal resection, photodynamic therapy, radiofrequency ablation, and cryotherapy. Finally, we focus on the studies that evaluate the efficacy of these imaging and ablation technologies in finding and eradicating neoplastic Barrett's esophagus.

Comparison of six immunohistochemical markers for the histologic diagnosis of neoplasia in Barrett's esophagus

In esophageal neoplasms, the histopathologic differentiation between Barrett's esophagus with or without intraepithelial neoplasia and adenocarcinoma is often challenging. Immunohistochemistry might help to differentiate between these lesions. The expression of CDX2, LI-cadherin, mucin 2 (MUC2), blood group 8 (BG8, Lewis(y)), claudin-2, and villin was investigated in normal gastroesophageal (n = 23) and in Barrett's (n = 17) mucosa, in low-grade (n = 12) and high-grade (n = 9) intraepithelial neoplasia (IEN) as well as in esophageal adenocarcinoma (n = 16), using immunohistochemistry. For CDX2 and LI-cadherin, the immunoreactivity score was highest in IEN while for MUC2, BG8, and villin, it dropped gradually from Barrett's via IEN to adenocarcinoma, and expression of Claudin-2 was only weak and focal in all lesions. The expression of MUC2 and LI-cadherin differed significantly between all examined lesions except between low-grade and high-grade IEN. MUC2 and LI-cadherin are useful immunohistochemical markers for the differentiation between normal glandular mucosa, Barrett's mucosa, IEN, and invasive carcinoma of the esophagus; however, none of the examined markers was helpful for the differentiation between low-grade and high-grade IEN.

CDX2 and LI-cadherin expression in esophageal mucosa: use of both markers can facilitate the histologic diagnosis of Barrett's esophagus and carcinoma

BACKGROUND

Barrett's mucosa is a risk factor for esophageal adenocarcinoma and should be detected at an early stage. CDX2 and liver-intestine (LI)-cadherin are intestine-specific markers. Aberrant CDX2 expression has been demonstrated in Barrett's metaplasia, esophagitis, and intestinal metaplasia of the stomach.

METHODS

The relationship between CDX2 and LI-cadherin expression was investigated in normal gastroesophageal (n = 24) and in Barrett's (n = 20) mucosa, in low-grade (n = 15) and high-grade (n = 13) intraepithelial neoplasia (IEN) as well as in esophageal adenocarcinoma (n = 16), using immunohistochemistry.

RESULTS

Nuclear positivity for CDX2 coupled with membranous expression of LI-cadherin was observed in about 70% of the epithelial cells of Barrett's mucosa. The intensity of staining and the percentage of positive cells increased within the sequential steps of low-grade to high-grade IEN, whereas the normal cylindric epithelium lacked the expression of both. In adenocarcinoma, the expression of LI-cadherin and CDX2 was significantly weaker or absent.

CONCLUSIONS

CDX2 and LI-cadherin are sensitive markers of intestinal metaplasia with or without dysplasia in the upper gastrointestinal tract. Both can be helpful for the early histologic diagnosis of Barrett's esophagus and its subsequent lesions; however, they do not significantly discern between different grades of dysplasia.

Histology of metaplasia and dysplasia in Barrett's esophagus

The histologic diagnosis of Barrett's dysplasia requires the identification of intestinal metaplasia, which often presents a challenge due to sampling error, observer variation, and difficulty in histologic interpretation. Particularly problematic is the separation of negative, indefinite, and low-grade dysplasia, the varied histological appearances of high-grade dysplasia, and the diagnosis of suboptimal biopsy material. This article seeks to aid in the histological evaluation of metaplasia and dysplasia in Barrett's esophagus.

Dendritic cell-associated immune inflammation of cardiac mucosa: a possible factor in the formation of Barrett's esophagus

BACKGROUND

The development of Barrett's esophagus is poorly understood, but it has been suggested that cardiac mucosa is a precursor of intestinal type metaplasia and that inflammation of cardiac mucosa may play a role in the formation of Barrett's esophagus. The present study was undertaken to examine the presence and distribution of immune-inflammatory cells in cardiac mucosa, specifically focusing on dendritic cells because of their importance as regulators of immune reactions.

MATERIAL AND METHODS

Endoscopic biopsy specimens were obtained from 12 patients with cardiac mucosa without Barrett's esophagus or adenocarcinoma and from 21 patients with Barrett's esophagus without dysplasia (intestinal metaplasia). According to histology, in nine of the 21 specimens with Barrett's esophagus, areas of mucosa composed of cardiac type epithelium-lined glands were present as well. Immunohistochemical staining and electron microscopy were used to examine immune-inflammatory cells in paraffin-embedded sections.

RESULTS

Immune-inflammatory cells, including T cells, B cells, dendritic cells, macrophages, and mast cells, were present in the connective tissue matrix that surrounded cardiac type epithelium-lined glands in all patients with cardiac mucosa. Clustering of dendritic cells with each other and with lymphocytes and the intrusion of dendritic cells between glandular mucus cells were observed. In the Barrett's esophagus specimens that contained cardiac type glands, computerized CD83 expression quantitation revealed that there were more dendritic cells in cardiac mucosa than in intestinal metaplasia.

CONCLUSION

Immune-inflammatory infiltrates containing dendritic cells are consistently present in cardiac mucosa. The finding of a larger number of dendritic cells in areas of cardiac mucosa in Barrett's esophagus biopsies suggests that the immune inflammation of cardiac mucosa might play a role in modifying the local tissue environment to promote the development of specialized intestinal type metaplasia.

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

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

DNA ploidy abnormalities in basal and superficial regions of the crypts in Barrett's esophagus and associated neoplastic lesions

The purpose of this study was to define the zonal DNA content distribution in the basal versus the superficial crypt cells in Barrett's esophagus (BE) and related neoplastic lesions. One hundred and five tissue sections of BE patients and 12 gastric tissue section as controls were stained with hematoxylin-eosin and Feulgen and high-fidelity DNA histograms were generated from whole crypts (n=117) and also separately from the basal and superficial portions of the crypts (n=71). Three parameters were analyzed: (1) peak DNA index (DI), classified into diploidy (DI=0.9-1.1) or aneuploidy (DI>1.1), the latter of which was further divided into 3 types: mild (DI=1.1-1.3), moderate (DI=1.3-1.8), and severe (DI>1.8). (2) Heterogeneity index (HI), representing groups of cells with different DNA content. (3) Percentage of cells with DI exceeding 5N rate (5N-ER). In full crypts, compared with gastric controls, the prevalence of DNA aneuploidy increased significantly (P<0.01) from nondysplastic BE to basal crypt dysplasia (BCD), low-grade dysplasia (LGD), high-grade dysplasia (HGD), and adenocarcinoma (AC). Nondysplastic BE, BCD, and LGD had mostly mild aneuploidy, and the majority of HGD and AC had either moderate or severe aneuploidy. In addition, both HI and 5N-ER increased progressively from BCD and LGD to HGD and AC (P<0.01). When analyzed separately, the superficial crypt cells were diploid in nondysplastic BE and BCD, but were aneuploid in 50% of LGD and 100% of HGD cases. In contrast, basal crypt cells were aneuploid in 37% of nondysplastic BE, 50% of BCD, 73% of LGD, and 100% of HGD cases. A similar progressive increase in the HI and 5N-ER values in basal crypt cells was observed with dysplastic progression. The changes in DNA ploidy profiles of basal crypt cells in BCD and LGD were remarkably similar. These results suggest that with neoplastic progression, dysplastic changes in BE begin in the basal crypt cells and then extend further up the crypts, and BCD represents a true early form of dysplasia limited to the crypt bases.

Phenotypic differences between esophageal and gastric intestinal metaplasia

Intestinal metaplasia is a cancer precursor in the esophagus and the stomach. Marked differences exist between the carcinogenic processes in the two locations in terms of natural history and clinical significance. We investigated biopsies from 52 patients with Barrett's esophagus and from 50 patients with gastric intestinal metaplasia in an attempt to throw light on their pathogenic processes. Morphologic characteristics, presence of Helicobacter pylori (H. pylori), and markers of differentiation, inflammation, and proliferation were evaluated by histochemical and immunohistochemical techniques. The area covered by incomplete type of intestinal metaplasia and the proportion of sulfomucins were significantly higher in the esophagus than in the stomach. Immunoreactivity with MUC1, MUC2, MUC5AC, Das-1, cytokeratins 7 and 20, inducible nitric oxide synthase and cyclooxygenase-2 antibodies was also significantly greater in Barrett's esophagus than in gastric intestinal metaplasia. In gastric intestinal metaplasia, the presence of MUC1, MUC5AC, Das-1 and cytokeratin 7 was restricted to areas with the incomplete type of metaplasia. Cell proliferation (Ki-67) was significantly higher in Barrett's esophagus than in gastric intestinal metaplasia. H. pylori was absent in all of the patients with Barrett's esophagus, while it was present in 70% of the patients with gastric intestinal metaplasia. Our observations made clear that Barrett's esophagus shares some phenotypic characteristics with gastric intestinal metaplasia, leading us to suggest that both could arise in response to injuries with eventual carcinogenic potential. However, the progression to more advanced lesions could be modulated by the nature of the carcinogenic insult.

[Evaluation of dysplasia in gastrointestinal diseases]

Dysplasia, or intraepithelial neoplasia, consists of noninvasive neoplastic cellular proliferation that may precede or accompany invasive neoplasia. Diagnosis is mainly based on histological criteria, which include cytological and structural alterations, since macroscopically identifiable lesions often do not occur. In all current classifications, dysplasia is divided in two categories, low- and high-grade, with the aim of attempting to evaluate risk and guide the therapeutic approach. The classification of the Vienna consensus aims to unity criteria and decrease interobserver variability in diagnosis. In the digestive tract, evaluation of epithelial dysplasia is especially important in four entities: Barrett's esophagus, chronic gastritis, inflammatory bowel disease, and colorectal adenomas. The criteria for diagnosis and dysplasia staging are the same in all these entities, but the therapeutic approach may vary according to the affected organ and the clinico-pathological context.

Large intra- and inter-individual variability of genes expression levels limits potential predictive value of molecular diagnosis of dysplasia in Barrett's esophagus

Barrett's esophagus represents a well-defined precursor lesion of esophageal adenocarcinoma, although only a subset of patients with these lesions advances to invasive cancer. Currently, reliable markers predicting neoplastic progression in Barrett's esophagus are lacking. The only clinically useful risk factor is the presence of dysplasia in Barrett's epithelium, but its use as a prognostic marker of disease progression has several significant limitations. Thus, identification of biomarkers of potential prognostic value in dysplasia development in Barrett's esophagus is highly important. The aim of the study was to determine if expression levels of selected genes support histologic diagnosis of dysplastic changes in Barrett's esophagus. Upon rigorous sampling and independent histopathologic examination of endoscopic specimens by two experienced gastrointestinal pathologists, 56 patients with Barrett's esophagus (16 negative for dysplasia, 15 with indefinite, 21 with low-grade, and 4 with high-grade dysplasia) were selected for molecular analysis. The relative mRNA levels of ten selected genes were estimated by quantitative real-time polymerase chain reaction (PCR) analysis. Although expression of nine genes showed trends toward down- or upregulation during progression from Barrett's esophagus without dysplasia to Barrett's esophagus with high-grade dysplasia, only a decrease in S100A2 mRNA levels was statistically significant (P<0.05). However, there was considerable variation among individuals and significant overlapping of ranges. Furthermore, detailed, comparative analysis of serial samples from Barrett's mucosa and normal squamous epithelium shows large intra-individual variability of gene expression levels. In conclusion, expression of this set of ten genes cannot be used as a molecular marker aiding histological examination of dysplasia in Barrett's esophagus. Significant inter- and intra-patient variations of gene expression levels makes use of the selected genes impractical.

High-fidelity DNA histograms in neoplastic progression in Barrett's esophagus

This study describes the high-fidelity DNA histograms in different stages of neoplastic progression to Barrett's adenocarcinoma (BAC). High-fidelity DNA histograms were obtained with image cytometry on sections, and were classified based on DNA index values of the peaks into diploid, mild aneuploid, moderate aneuploid and severe aneuploid. Heterogeneity index (HI) representing cells with different DNA content and the 5N exceeding cell fraction were determined. One hundred and eighty-seven cases, including 34 normal gastrointestinal mucosa (control), 66 Barrett's-specialized intestinal metaplasia (SIM), 22 low-grade dysplasia (LGD), 22 high-grade dysplasia (HGD) and 43 BAC were investigated. Controls showed sharp diploid peaks with HI values less than 13, and no 5N exceeding nuclei. SIM showed a spectrum of histograms including diploid, mild aneuploid and moderate aneuploid histograms. The frequency and severity of aneuploidy increased with worsening histological grades of dysplasia. All BAC cases were aneuploid, with moderate or severe aneuploidy. Marked elevated HI values (>20) and 5N exceeding fractions (>5%) were found in 5%, 32%, 50% and 88% of cases with SIM, LGD, HGD and BAC, respectively. The high-fidelity DNA histograms suggest that (1) Barrett's SIM may already be dysplastic in nature, and all BAC may be markedly aneuploid; and (2) elevated cellular DNA heterogeneity and 5N fractions may be markers of progressive chromosomal changes and 'unstable aneuploidy' that identifies progressive lesions.

COX-2, CDX2, and CDC2 immunohistochemical assessment for dysplasia-carcinoma progression in Barrett's esophagus

BACKGROUND

Immunohistochemical changes associated with development of cancer in Barrett's esophagus offer potential areas of intervention to prevent and manage esophageal cancer.

AIMS

To assess the role of cyclooxygenase 2, caudal-type homeobox transcription factor 2 and cell division cycle 2/cyclin-dependent kinase 1 in the Barrett's metaplasia-dysplasia-adenocarcinoma sequence.

PATIENTS AND METHODS

Specimens from 46 patients with Barrett's esophagus (39% without dysplasia, 33% with dysplasia and 28% with adenocarcinoma) were stained for cyclooxygenase 2, caudal-type homeobox transcription factor 2 and cell division cycle 2.

RESULTS

Cyclooxygenase 2: No expression differences between groups were found, except for adenocarcinomas (p=0.04). Caudal-type homeobox transcription factor 2: Nuclear positivity decreased from Barrett's esophagus without dysplasia (71.6%), to Barrett's esophagus with low grade dysplasia (35.3%), to Barrett's esophagus with high grade dysplasia (17.14%); in adenocarcinoma these percentages were intermediate between high and low grade dysplasia (30.5%). Cell division cycle 2: Expression on deeper glandular structures was 40% in Barrett's esophagus without dysplasia, 55.47% in Barrett's esophagus with dysplasia, and 63.84% in adenocarcinoma, with no statistical differences between groups. Concerning cells of the superficial layer, Barrett's esophagus with low grade dysplasia expressed focal positivity (p=0.0001 vs. no dysplasia); Barrett's esophagus with high grade dysplasia displayed diffuse positivity (p=0.0001 vs. no dysplasia and low grade dysplasia). A diffuse positivity was found in Barrett's esophagus with adenocarcinoma (p=0.0001 vs. no dysplasia and low grade dysplasia).

CONCLUSIONS

Further evaluation of cyclooxygenase 2, cell division cycle 2 and caudal-type homeobox transcription factor 2, in association with morphology, might help to improve the accuracy of diagnosis and be useful for the clinical-pathological assessment of patients with Barrett's esophagus.

High-frequency probe ultrasonography has limited accuracy for detecting invasive adenocarcinoma in patients with Barrett's esophagus and high-grade dysplasia or intramucosal carcinoma: a case series

AIM

To evaluate prospectively the accuracy of preoperative high-frequency (20 MHz) probe ultrasonography (HFPUS) for detecting invasive cancer in patients referred for esophagectomy because of an endoscopic biopsy diagnosis of high-grade dysplasia (HGD) or intramucosal carcinoma (ICA) in Barrett's esophagus (BE).

PATIENTS AND METHODS

Nine consecutive male patients (median age of 69 yr) who were referred for esophagectomy for HGD or ICA in BE agreed to participate. We performed conventional upper gastrointestinal endoscopy followed by HFPUS using a through-the-scope ultrasound probe (20 MHz), and we compared our preoperative findings with the pathologist's findings in the resected esophageal specimens.

RESULTS

There was complete agreement between the postoperative pathological findings and the preoperative HFPUS findings in only 4 of the 9 patients. HFPUS resulted in two false-negative diagnoses of esophageal cancer (both had T1 lesions in the resected specimens), one false-positive diagnosis of esophageal cancer, and two errors in tumor staging (1 understaged, 1 overstaged).

CONCLUSIONS

HFPUS has limited accuracy for identifying invasive cancer in patients found to have HGD or IMC in BE. Pending further refinements in technology, clinical management decisions in such patients should not be based solely on the results of HFPUS.

Mucin core polypeptide expression in the progression of neoplasia in Barrett's esophagus

We have previously demonstrated a specific pattern of mucin (MUC) core polypeptide expression in Barrett's esophagus (BE) characterized by MUC1 and MUC6 positivity in goblet cells in a proportion of cases. The aim of this study was to determine the pattern of MUC expression associated with the development and progression of dysplasia in BE. Endoscopic mucosal biopsies from 35 patients with BE (10 with no dysplasia, 6 with indefinite for dysplasia, 12 with low-grade dysplasia [LGD], and 7 biopsies with high-grade dysplasia [HGD]) were immunostained (ABC method) with antibodies against MUC1, MUC2, MUC3, MUC5AC, and MUC6. The extent and pattern of staining for each marker was evaluated in intestinalized Barrett's epithelium and in the various grades of dysplasia. For cases with dysplasia, staining was evaluated separately in nondysplastic epithelium adjacent to (<1 cm) and distant from (>2 cm) areas of dysplasia. In nondysplastic BE, MUC1, MUC2, MUC3, MUC5AC, and MUC6 stained 40%, 100%, 100%, 100%, and 90% of cases, respectively, in goblet or nongoblet columnar epithelium. With the progression of dysplasia (from metaplasia to indefinite, LGD and HGD), there was a significant decrease in expression of MUC1, MUC2, and MUC3, and alterations in the staining patterns of MUC5 and MUC6. In fact, MUC1 and MUC3 were entirely absent from all cases of HGD. Interestingly, BE-associated adenocarcinomas showed an MUC phenotype distinct from that of HGD, with expression of MUC1 and MUC3 in 47% and 67% of cases, and expression of MUC1 in a membranous pattern. There was no significant difference in MUC staining in nondysplastic BE between patients with and without dysplasia. Alterations in MUC expression occur in the progression of dysplasia in BE. However, none of these markers helps identify a subgroup of patients at increased risk for neoplasia.

The diagnostic utility of immunohistochemistry in distinguishing between epithelioid mesotheliomas and squamous carcinomas of the lung: a comparative study

As both mesotheliomas and squamous carcinomas can present a wide variety of morphological patterns, they can on occasion be confused. Recently, some groups of investigators have called attention to the difficulties that sometimes exist in distinguishing between these malignancies and the need to define a panel of markers that can assist in reaching the correct diagnosis. The aim of the present study is to compare the value of the various immunohistochemical markers currently available for the diagnosis of mesothelioma and squamous carcinoma of the lung. A total of 30 epithelioid pleural mesotheliomas exhibiting a solid or predominantly solid pattern, and 30 nonkeratinizing squamous carcinomas of the lung were investigated for the expression of the following markers: podoplanin, calretinin, mesothelin, WT1, keratin 5/6, keratin 7, p63, carcinoembryonic antigen (CEA), MOC-31, Ber-EP4, B72.3, BG-8 (Lewis(y)), leu-M1 (CD15), and thyroid transcription factor-1 (TTF-1). All 30 (100%) of the mesotheliomas reacted for calretinin, mesothelin and keratin 7, 93% each for podoplanin, WT1 and keratin 5/6, 13% for Ber-EP4, 7% each for p63, MOC-31 and BG-8, and 0% for B72.3, CEA, leu-M1 and TTF-1. All 30 (100%) of the squamous carcinomas were positive for p63 and keratin 5/6, 97% for MOC-31, 87% for Ber-EP4, 80% for BG-8, 77% for CEA, 57% for keratin 7, 40% for calretinin and B72.3, 30% for leu-M1, 27% for mesothelin, 15% for podoplanin, and 0% for WT 1 and TTF-1. After analyzing the results, it is concluded that from a practical point-of-view, a combination of two positive mesothelioma markers (WT1 and calretinin or mesothelin) with two negative mesothelioma markers (p63 and MOC-31) would allow the differential diagnosis to be established between epithelioid mesotheliomas and squamous carcinomas of the lung in nearly all instances.

Use of an improved zirconyl hematoxylin stain in the diagnosis of Barrett's esophagus

Barrett's esophagus is a precancerous condition characterized by replacement of the normal stratified squamous epithelium by a simple columnar epithelium with goblet cells that secrete an acidic mucin. As originally formulated, fresh solutions of zirconyl hematoxylin stain goblet cells poorly. An improved formula, quintupling the amount of oxidant, yields zirconyl hematoxylin solutions that stain goblet cells darkly even when fresh. The improved zirconyl hematoxylin can be used in place of alcian blue in the diagnosis of Barrett's esophagus. The ingredients of zirconyl hematoxylin are always readily available and are generally recognized as safe.

DNA index determination with Automated Cellular Imaging System (ACIS) in Barrett's esophagus: comparison with CAS 200

Background

For solid tumors, image cytometry has been shown to be more sensitive for diagnosing DNA content abnormalities (aneuploidy) than flow cytometry. Image cytometry has often been performed using the semi-automated CAS 200 system. Recently, an Automated Cellular Imaging System (ACIS) was introduced to determine DNA content (DNA index), but it has not been validated.

Methods

Using the CAS 200 system and ACIS, we compared the DNA index (DI) obtained from the same archived formalin-fixed and paraffin embedded tissue samples from Barrett's esophagus related lesions, including samples with specialized intestinal metaplasia without dysplasia, low-grade dysplasia, high-grade dysplasia and adenocarcinoma.

Results

Although there was a very good correlation between the DI values determined by ACIS and CAS 200, the former was 25% more sensitive in detecting aneuploidy. ACIS yielded a mean DI value 18% higher than that obtained by CAS 200 (p < 0.001; paired t test). In addition, the average time required to perform a DNA ploidy analysis was shorter with the ACIS (30–40 min) than with the CAS 200 (40–70 min). Results obtained by ACIS gave excellent inter-and intra-observer variability (coefficient of correlation >0.9 for both, p < 0.0001).

Conclusion

Compared with the CAS 200, the ACIS is a more sensitive and less time consuming technique for determining DNA ploidy. Results obtained by ACIS are also highly reproducible.

Biologic properties of columnar epithelium underneath reepithelialized squamous mucosa in Barrett's esophagus

Chronic proton pump inhibitor (PPI) therapy may lead to partial regression of Barrett's esophagus (BE), resulting in the development of reepithelialized islands of squamous mucosa that may cover the underlying BE. The purpose of this study was to evaluate the clinical, histologic, and biologic characteristics of BE that is situated underneath squamous islands (BUSI). A total of 97 mucosal biopsies from 44 BE patients with BUSI were evaluated for a variety of histologic features (eg, type of epithelium, anatomic relationship of the underlying glands to the luminal surface, presence of adjacent mucosal glands or ducts, and the presence and degree of dysplasia), and immunostained for Ki-67, cyclin D1, and p53. BUSI was compared with adjacent areas of BE for all parameters. A clinical control group consisting of 50 BE patients without microscopic evidence of BUSI was selected for comparison of clinical and endoscopic features. The study group (34 males, 10 females; mean age, 67 years; mean length of BE, 5.5 cm) consisted of 27 (61%) and 12 (27%) patients on low- and high-dose PPI, respectively. On endoscopy, visible islands of squamous mucosa were noted in only 43% of study group patients (despite the presence of BUSI microscopically in all cases); one island was noted in 2%, multiple islands in 27%, and extensive islands in 14% of patients. The extent of squamous islands was unrelated to PPI dose. The study group was significantly more likely to have endoscopic evidence of extensive squamous islands compared with the control group (P = 0.009). Histologically, 89% of biopsies with BUSI showed intestinal-type, and 11% showed cardia-type, epithelium. Low- and high-grade dysplasia was noted in 4 (4%) and 5 (5%) biopsies, respectively. All patients with dysplasia in BUSI also showed dysplasia in other areas of the esophagus as well. Interestingly, BUSI reached the mucosal surface either by penetrating directly through, or by wrapping around, islands of squamous epithelium, in 68% of biopsies. Twenty-one percent of biopsies showed BUSI adjacent to submucosal glands or ducts. BUSI showed a significantly lower Ki-67 proliferation rate (29% vs. 49%, P < 0.001), and a lower, albeit nonsignificant, degree of cyclin D1 (16% vs. 29%) and p53 (4% vs. 17%) positivity in comparison to adjacent areas of BE. Furthermore, significantly lower proliferation rates were observed in BUSI that did not reveal an opening to the mucosal surface in comparison to foci that did. BUSI is phenotypically similar to typical surface BE but shows less severe proliferative abnormalities, particularly in buried glands that have no detectable connection to the esophageal lumen. Reduced proliferation may be due either to decreased exposure to luminal contents or to disruption of sloughing of surface epithelial cells into the crypt lumen. Prospective studies of large numbers of patients with BUSI will be required to determine the magnitude of its risk of progression to cancer.