Methylene blue-directed biopsies improve detection of intestinal metaplasia and dysplasia in Barrett's esophagus

Enhanced endoscopic imaging and gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) and GERD-related symptoms are common, and affect 25% to 30% of the general population. Upper gastrointestinal endoscopy of the esophagus has been the most widely used modality for the diagnosis and grading of reflux disease. Endoscopic imaging today has evolved beyond the confines of routine white light endoscopy (WLE) to advanced optical imaging with a precise and real time endoscopic diagnosis. These technological advances have helped circumvent the limitation of WLE in reflux disease by a) improved detection of subtle irregularities, b) characterization of anomalies, and c) possible optical biopsies providing real-time diagnosis. This review attempts to define the current status of these newer technologies vis-a-vis the diagnosis and management of gastroesophageal reflux disease.

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.

Molecular imaging for guiding oncologic prognosis and therapy in esophageal adenocarcinoma

In the past 30 years, the incidence of esophageal adenocarcinoma (ACA) has increased significantly. Sadly, advances in treatment have not followed the same trend, and the prognosis for patients with esophageal ACA remains poor, with a 5-year survival rate of only 15%. Like most cancers, early detection is the key to improving prognosis, but this outcome has proven difficult in the esophagus for several reasons: 1) patients present with advanced disease because "alarm symptoms," such as dysphagia, occur at a late stage, and 2) high-grade dysplasia (HGD) and early ACA are not visible on routine surveillance endoscopy. Currently, the recommended surveillance strategy involves collection of random biopsies, an imperfect technique that is limited by sampling error and is infrequently used because of the considerable time and cost it requires. Even in patients with biopsy-proven dysplasia, adequate guidance for clinical management decisions is still lacking. Dysplasia alone is not an entirely reliable biomarker for the risk of progression to ACA because the natural history of this condition is extremely variable. Clearly, there is a need for additional biomarkers that can better characterize this disease and thus improve our ability to treat patients on an individual basis. As we better understand the molecular changes that lead to the development of this cancer, new molecular biomarkers are needed to allow for more personalized diagnoses, surveillance, and treatment. Targeted agents against epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), and vascular endothelial growth factor (VEGF) are currently being evaluated for their role in combination chemotherapy for metastatic esophageal ACA. As these studies progress, a reliable approach for determining receptor status in individual patients is essential. Molecular imaging uses fluorescent probes that target specific cell-surface receptors, and has the potential to evaluate an individual patient's gene expression profile. By topically applying fluorescent probes to dysplastic epithelium during endoscopy, a variety of receptors can be visualized, and the response to treatment can be monitored in real time. This technique can mitigate the limitations of current surveillance protocols, allow for improved cancer detection, and be used for personalized treatment in the future.

Endoscopic methods

Endoscopic methods to recognise and treat early gastrointestinal malignancies have increased in recent years. This has resulted in more lesions being diagnosed at an early stage and a shift away from invasive surgery towards endoscopic resection. However, it is necessary for the endoscopist to understand the key principles behind advanced endoscopic diagnosis and the new therapeutic options available. This chapter will review the advances in endoscopic techniques and methods which are changing the way we diagnose and treat these cancers. It will examine the general principles behind advanced endoscopy and then examine their application in Barrett's neoplasia, gastric cancer and the dysplasia associated lesions or masses associated with ulcerative colitis. It will focus on the best techniques for each of the above pathology.

Endoscopic evaluation and advanced imaging of Barrett's esophagus

Enhanced visualization techniques are available for Barrett's esophagus and have promise in the detection of dysplasia and cancer. Several of these techniques, such as narrow band imaging and chromoendoscopy, are being applied clinically. These techniques will allow the endoscopist to screen the surface of the Barrett's esophagus to detect areas of neoplasia. Once detected, it is hoped that either magnification techniques, such as confocal laser endomicroscopy, or spectroscopic techniques can be of value in allowing in vivo real-time diagnostic capabilities.

Acetic acid spray is an effective tool for the endoscopic detection of neoplasia in patients with Barrett's esophagus

BACKGROUND & AIMS

Diagnosis of Barrett's neoplasia requires collection of large numbers of random biopsy samples; the process is time consuming and can miss early-stage cancers. We evaluated the role of acetic acid chromoendoscopy in identifying Barrett's neoplasia.

METHODS

Data were collected from patients with Barrett's esophagus examined at a tertiary referral center, between July 2005 and November 2008 using Fujinon gastroscopes and EPX 4400 processor (n = 190). All procedures were performed by a single experienced endoscopist. Patients were examined with white light gastroscopy and visible abnormalities were identified. Acetic acid (2.5%) dye spray was used to identify potentially neoplastic areas and biopsy samples were collected from these, followed by quadrantic biopsies at 2 cm intervals of the remaining Barrett's mucosa. The chromoendoscopic diagnosis was compared with the ultimate histological diagnosis to evaluate the sensitivity of acetic acid chromoendoscopy.

RESULTS

Acetic acid chromoendoscopy had a sensitivity of 95.5% and specificity of 80% for the detection of neoplasia. There was a correlation between lesions predicted to be neoplasias by acetic acid and those diagnosed by histological analysis (r = 0.98). There was a significant improvement in the detection of neoplasia using acetic acid compared with white light endoscopy (P = .001).

CONCLUSIONS

Analysis of this large series showed that acetic acid-assisted evaluation of Barrett's esophagus detects neoplasia better than white light endoscopy, with sensitivity and specificity equal to that of histological analysis.

Endoscopic techniques for recognizing neoplasia in Barrett's esophagus: which should the clinician use?

PURPOSE OF REVIEW

The key to prevention and cure of esophageal adenocarcinoma is the detection and eradication of neoplasia in patients with Barrett's esophagus. Multiple tools and technologies are emerging for this purpose.

RECENT FINDINGS

A detailed white light examination with high-resolution endoscopy and recognition of lesions is paramount. A variety of imaging modalities are being studied for the detection of neoplasia in Barrett's esophagus. Chromoendoscopy, narrow band imaging, and autofluorescence provide a way to target suspicious areas. Confocal endomicroscopy and optical coherence tomography are means to pinpoint imaging to obtain information about the tissue microarchitecture.

SUMMARY

The key to detection of neoplasia is a careful white light examination with high-resolution endoscopy and recognition of lesion characteristics. Additional imaging modalities may enhance targeting of lesions or provide more information at a focused level. Many of these modalities have yet to be validated in prospective randomized, multicenter trials.

Optimal endoluminal treatment of Barrett's esophagus: integrating novel strategies into clinical practice

Endoluminal therapy has become the first-choice treatment over the last 5 years for early Barrett's neoplasia limited to the mucosa. Long-term follow-up data on endoscopic resection have demonstrated the oncological safety of endoscopic resection in comparison to surgery. However, there is a high rate of recurrent disease, which can be avoided using additional ablation of the remaining Barrett. Radiofrequency ablation was recently introduced as an efficacious means to ablate Barrett's epithelium with a better safety profile than older ablation techniques. Recent studies show that endoscopic resection can be safely combined with radiofrequency ablation for treating dysplastic Barrett's after removal of visible lesions. This constitutes a completely new treatment paradigm that will be integrated in routine clinical practice in the forthcoming years.

Confocal laser endomicroscopy in Barrett's esophagus and endoscopically inapparent Barrett's neoplasia: a prospective, randomized, double-blind, controlled, crossover trial

BACKGROUND

The detection of high-grade dysplasia and cancer in Barrett's esophagus (BE) can be challenging. Confocal laser endomicroscopy (CLE) allows in vivo visualization of mucosal histology during endoscopy.

OBJECTIVE

To determine whether CLE with optical biopsy and targeted mucosal biopsy improves the diagnostic yield of endoscopically inapparent, BE-associated neoplasia compared to standard endoscopy with a 4-quadrant, random biopsy protocol.

DESIGN

Prospective, double-blind, randomized, crossover study.

SETTING

Single, tertiary-care academic center.

PATIENTS

This study involved patients with BE undergoing routine surveillance or referred for treatment of nonlocalized, endoscopically inapparent, BE-associated neoplasia.

INTERVENTION

All participants underwent both a confocal endomicroscopy with a targeted biopsy procedure and standard endoscopy with a 4-quadrant biopsy procedure in a randomized order.

MAIN OUTCOME MEASUREMENTS

Increase in diagnostic yield for neoplasia, reduction in mucosal biopsy number, final pathologic diagnosis.

RESULTS

CLE with targeted biopsy almost doubled the diagnostic yield for neoplasia and was equivalent to the standard protocol for the final diagnosis of neoplasia. Two thirds of patients in the surveillance group did not need any mucosal biopsies at all.

LIMITATION

Single-center study.

CONCLUSION

CLE with targeted biopsy significantly improves the diagnostic yield for endoscopically inapparent BE neoplasia compared to a standard endoscopy with a random-biopsy protocol. CLE with targeted biopsy also greatly reduces the number of biopsies needed per patient and allows some patients without neoplasia to completely forgo mucosal biopsy.

New technologies for imaging of Barrett's esophagus

There have been many developments in endoscopy-based imaging for the detection of Barrett's syndrome, dysplasia, and neoplasia in patients with Barrett's esophagus. This article reviews the studies on and compares the efficacy of several important endoscopic imaging modalities. Some of these technologies have already achieved regulatory approval, commercial availability, and establishment of clinical utility and practical application. The future of imaging for Barrett's syndrome likely rests with the development of molecular targeting with dysplasiatargeted probes that have been conjugated to dyes or nanoparticles.

Diagnostic yield of methylene blue chromoendoscopy for detecting specialized intestinal metaplasia and dysplasia in Barrett's esophagus: a meta-analysis

BACKGROUND

The reported yield of methylene-blue (MB) chromoendoscopy targeted biopsy in detecting specialized intestinal metaplasia (SIM) and, more importantly, dysplasia in patients with Barrett's esophagus (BE) has shown variable results.

OBJECTIVE

To perform a meta-analysis of published studies for assessment of the diagnostic yield of techniques of chromoendoscopy compared with conventional 4-quadrant random biopsy (RB) in detection of SIM and dysplasia in patients with BE.

DESIGN

A literature search of the MEDLINE, EMBASE, and the Cochrane Databases was performed, along with a search of PubMed and a manual search of cross-references of eligible articles. Data on yield of both modalities were extracted and analyzed to estimate weighted incremental yield (IY) and 95% CIs of MB over RB using a fixed-effects or random-effects model, as appropriate, based on whether homogeneity or heterogeneity, respectively, was indicated by Cochrane's Q chi(2) test.

PATIENTS

A total of 450 patients with BE were reported in 9 studies included in the meta-analysis.

RESULTS

There was no significant IY with MB over RB for detection of SIM (IY 4%; 95% CI, -7% to 16%; 6 studies, n = 251), dysplasia (IY 9%; 95% CI, -1% to 20%; 9 studies, n = 450), and high-grade dysplasia and/or early cancer (IY 5%; 95% CI, -1% to 10%; 8 studies, n = 405).

LIMITATIONS

Only data on MB were analyzed because of limited availability of data for other chromoendoscopy dyes, minor variations in inclusion and exclusion criteria, and the small sample size, and because differences in application technique could have led to an underestimation of the diagnostic yield of MB chromoendoscopy.

CONCLUSION

The technique of MB chromoendoscopy has only a comparable yield with RB for the detection of SIM and dysplasia during endoscopic evaluation of patients with BE.

Chromoendoscopy

Chromoendoscopy involves the use of stains or dyes during endoscopy to improve the visualization and characterization of the gastrointestinal mucosa. Its main clinical application is the detection of dysplasia or early cancer of the gastrointestinal tract in individuals with pre-malignant conditions or hereditary and environmental factors that predispose them to cancer. The utility of chromoendoscopy has been mostly studied in squamous cell carcinoma of the esophagus, Barrett's esophagus, gastric cancer, colorectal polyps, and chronic ulcerative colitis. Although chromoendoscopy has been shown to be feasible and safe, several limitations have prevented its widespread use in endoscopy. Despite this, chromoendoscopy remains a useful adjunct to standard white light endoscopy in the visualization of mucosal lesions, which may potentially improve tissue diagnosis and impact patient care.

Barrett's oesophagus

Barrett's oesophagus is a metaplastic change of the lining of the oesophagus, such that the normal squamous epithelium is replaced by specialised or intestinalised columnar epithelium. The disorder seems to be a complication of chronic gastro-oesophageal reflux disease, although asymptomatic individuals might also be affected, and it is a risk factor for the development of oesophageal adenocarcinoma, a cancer with rapidly increasing incidence in developed societies. We review the presentation, epidemiology, and risk factors for this condition. We discuss the molecular changes necessary for the development of Barrett's oesophagus and its progression to cancer, and new strides in both the endoscopic detection of the lesion and the treatment of dysplastic disease. Also, we assess the effectiveness of efforts to screen patients at risk of Barrett's oesophagus, and whether such efforts avert cancer death. We conclude with a discussion of future directions for research, focusing on treatment of early neoplasia, and modifications of current practices to show our evolving understanding of this condition.

Advances in endoscopic imaging of the esophagus

The introduction of flexible fiberoptic endoscopy in the 1960s was a major step forward in the diagnosis and management of various esophageal disorders. Since then, there has been steady progress in the development of novel gastrointestinal endoscopy techniques. Magnification and high-resolution endoscopy, chromoendoscopy, narrow-band imaging, autofluorescence imaging, and confocal laser endomicroscopy are some of the recent advances that have shown promise in the diagnosis of squamous cell carcinoma, gastroesophageal reflux disease, Barrett's esophagus, and adenocarcinoma of the esophagus. The purpose of this review is to summarize the recent advances in endoscopic imaging of the esophagus and their practical application for the gastroenterologist.

Novel imaging modalities in the detection of oesophageal neoplasia

The prognosis of oesophageal neoplasia is dependent on the stage of the disease at the time of detection. Early lesions have an excellent prognosis in contrast to more advanced stages that usually have a dismal prognosis. Therefore, the early detection of these lesions is of the utmost importance. In recent years, several new techniques have been introduced to improve the endoscopic detection of early lesions. The most important improvement, in general, has been the introduction of high-resolution/high-definition endoscopy into daily clinical practice. The value of superimposing techniques such as chromoendoscopy, narrow band imaging and computed virtual chromoendoscopy onto high-resolution/high-definition endoscopy will have to be proven in randomised cross-over trials comparing these techniques with standard techniques. Important future adjuncts to white-light endoscopy serving as 'red-flag' techniques for the detection of early neoplasia may be broad field functional imaging techniques such as video autofluorescence endoscopy. In addition, real-time histopathology during endoscopy has become possible with endocytoscopy and confocal endomicroscopy. The clinical value of these techniques needs to be ascertained in the coming years.

Prospective, controlled tandem endoscopy study of narrow band imaging for dysplasia detection in Barrett's Esophagus

BACKGROUND & AIMS

High-resolution endoscopy with narrow band imaging (NBI) enhances the visualization of mucosal glandular and vascular structures. This study assessed whether narrow band targeted biopsies could detect advanced dysplasia using fewer biopsy samples compared with standard resolution endoscopy.

METHODS

We conducted a prospective, blinded, tandem endoscopy study in a tertiary care center with 65 patients with Barrett's esophagus undergoing evaluation for previously detected dysplasia. Standard resolution endoscopy was used first to detect visible lesions. Narrow band endoscopy was then used by another gastroenterologist to detect and biopsy areas suspicious for dysplasia. The lesions initially detected by standard resolution endoscopy were then disclosed and biopsied, after biopsy of the lesions targeted with NBI. Finally, random 4-quadrant biopsies were taken throughout the segment of Barrett's mucosa.

RESULTS

Higher grades of dysplasia were found by NBI in 12 patients (18%), compared with no cases (0%) in whom standard resolution white light endoscopy with random biopsy detected a higher grade of histology (P < .001). Correspondingly, narrow band directed biopsies detected dysplasia in more patients (n = 37; 57%) compared with biopsies taken using standard resolution endoscopy (n = 28; 43%). In addition, more biopsies were taken using standard resolution endoscopy with random biopsy compared with narrow band targeted biopsies (mean 8.5 versus 4.7; P < .001).

CONCLUSIONS

In patients evaluated for Barrett's esophagus with dysplasia, NBI detected significantly more patients with dysplasia and higher grades of dysplasia with fewer biopsy samples compared with standard resolution endoscopy.

External validation of a classification for methylene blue magnification chromoendoscopy in premalignant gastric lesions

BACKGROUND

Conventional endoscopy has low sensitivity, specificity, and interobserver agreement for the diagnosis of gastric atrophy, intestinal metaplasia, and dysplasia. Magnification chromoendoscopy (ME) may optimize the evaluation of premalignant gastric lesions.

OBJECTIVE AND DESIGN

As part of a multicenter trial, we aimed at validating a previously proposed classification for gastric methylene blue ME at a different center. SETTING, PATIENTS, AND INTERVENTIONS: A sample of patients (n = 42) with previously diagnosed chronic atrophic gastritis with or without intestinal metaplasia underwent ME (Pentax EG-3430Z) with 1% methylene blue by 2 endoscopists.

MAIN OUTCOME MEASUREMENTS

A simplified version of a previously published ME classification (group I, group II [further divided into subgroups IIE and IIF], and group III) was used for macroscopic lesions (n = 203) with Sydney-Houston and Vienna classifications being used for histologic analysis (n = 479 biopsy specimens).

RESULTS AND LIMITATIONS

Excellent reproducibility (wK = 0.92 [95% CI, 0.88-0.96]) was observed for classification in groups and substantial reproducibility (wK = 0.78 [95% CI, 0.72-0.84]) was found for classification in subgroups. Global validity was 82% (range 78%-86%), showing no false negatives (sensitivity of 100% [1/1 biopsy]) and a very low rate of false positives (specificity 99% [297/299 biopsies]) for dysplasia detection.

CONCLUSIONS

This classification for methylene blue ME was highly reproducible and valid for the diagnosis of premalignant gastric lesions when used in a center different from that involved in its conception. Despite requiring an unconventional endoscope and a longer procedure, these results could reinforce ME as a valuable technique in the surveillance of patients at risk for gastric cancer.

The usefulness of chromoendoscopy with methylene blue in Barrett's metaplasia and early esophageal carcinoma

BACKGROUND

Barrett's esophagus is a condition that is premalignant for adenocarcinoma of the esophagus and the esophagogastric junction. Early detection of Barrett's metaplasia and dysplasia is very important to decrease the mortality and morbidity from esophageal adenocarcinoma cancer. This study aimed to evaluate the effectiveness of methylene blue-targeted biopsies in the differential diagnosis of intestinal metaplasia, dysplasia, and superficial esophageal carcinoma.

METHODS

A total of 109 patients (43 women and 66 men; average age, 62.32 +/- 10.61 years; range, 33-82 years) were enrolled for the study. Four groups were designed before endoscopic examinations. The patients for these groups were selected at the conventional endoscopy, and then chromoendoscopy was performed. The esophagus was stained with methylene blue, after which six biopsies were taken from stained and unstained areas.

RESULTS

Conventional and chromoendoscopic assessments were compared with histopathologic examination. The sensitivity of chromoendoscopy for Barrett's epithelium was superior to that of conventional endoscopy (p < 0.05). However, there was no statistical difference between the two methods in the diagnosis of esophagitis or esophageal carcinoma (p > 0.05). Stained biopsies were superior to unstained biopsies in terms of sensitivity for Barrett's epithelium and esophageal carcinoma (p < 0.001).

CONCLUSION

Chromoendoscopy is useful for delineating Barrett's epithelium and for indicating the correct location for securing biopsies where dysplasia or early esophageal cancer is suspected.

A randomized comparison of methylene blue-directed biopsy versus conventional four-quadrant biopsy for the detection of intestinal metaplasia and dysplasia in patients with long-segment Barrett's esophagus

OBJECTIVES

Methylene blue (MB) selectively stains specialized intestinal metaplasia (SIM) and may assist in surveying a columnar-lined esophagus for Barrett's esophagus associated dysplasia.

METHODS

This is a prospective, randomized crossover study comparing 4-quadrant random biopsies (4QB) versus MB-directed biopsies for the detection of SIM and dysplasia in 48 patients with long segment Barrett's esophagus (LSBE). Patients randomly underwent two endoscopies over a 4-wk time period with either 4QB or MB-directed biopsies as their first or second exam. Our aim was to correlate stain intensity with histology.

RESULTS

The sensitivity of MB for SIM and dysplasia was 75.2% and 83.1%, respectively. The yield of 4QB for identifying nondysplasia SIM was 57.6% (523/917) and for dysplasia was 12% (111/917). Dark staining was significantly associated with histologic grade (P < 0.007). The final diagnosis was correct in 43 (90%) patients using MB and in 45 (94%) using 4QB. The 4QB technique missed dysplasia in 3 of 21 patients while MB biopsies missed dysplasia in 5 of 21 patients. The discordance between the two techniques was not significant (P= 0.727, McNemar's test). The mean number of biopsies taken during 4QB was 18.92 +/- 6.36 and with MB was 9.23 +/- 2.89 (P < 0.001).

CONCLUSION

MB requires significantly fewer biopsies than 4QB to evaluate for SIM and dysplasia. Dark staining correlates more with HGD than LGD in our experience. While MB is not more accurate than 4QB, MB may help to define areas to target for biopsy during surveillance endoscopy in patients with LSBE.

American Gastroenterological Association (AGA) Institute technology assessment on image-enhanced endoscopy

This document presents the official recommendations of the American Gastroenterological Association (AGA) Institute Technology Assessment on "Image-Enhanced Endoscopy." It was approved by the Clinical Practice and Economics Committee on August 3, 2007, and by the AGA Institute Governing Board September 27, 2007.

Application of in vivo stain of methylene blue as a diagnostic aid in the early detection and screening of oral squamous cell carcinoma and precancer lesions

BACKGROUND

Early detection of oral malignant or precancerous lesion by screening individuals with high-risk factors may identify candidates who should receive treatment to prevent cancer progression and reduce patient mortality. Among the diagnostic tools, in vivo staining is advocated as a simple, inexpensive, and fairly sensitive method.

METHODS

The present study involved the examination of 58 patients suspected of having oral malignant or precancerous lesions by methylene blue staining. The results of methylene blue uptake were compared with a simultaneous biopsy of these lesions. The pathologically confirmed precancers and cancers were the positive targets of this screening, while benign epithelial lesions were sorted as negative subjects of screening.

RESULTS

The results revealed sensitivity of 90%, specificity of 69%, positive predictive value of 74%, and negative predictive value of 87%.

CONCLUSION

We consider that methylene blue staining is a useful diagnostic adjunct in a large, community-based oral cancer screening program for high-risk individuals.

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

OBJECTIVE

It is well known that low-grade intraepithelial neoplasia (LGIN) in Barrett's oesophagus (BE) might progress to high-grade intraepithelial neoplasia (HGIN) or carcinoma. Since accurate diagnosis of LGIN is difficult, general pathologists are frequently uncertain about the diagnosis of LGIN and its follow-up risks. The purpose of this study was to analyse the divergence between the diagnoses of general and specialized gastrointestinal pathologists.

MATERIAL AND METHODS

Fifty consecutive patients with a previous diagnosis of LGIN in BE, made by a general pathologist, were included in our study. The histopathological slides of every patient were reassessed in a blinded fashion by two specialized gastrointestinal (GI) pathologists. Inter-observer variability was calculated using kappa statistics.

RESULTS

LGIN was confirmed by specialized pathologists in only 25/50 patients (50%). Twenty-one patients (42%) had Barrett's metaplasia without intraepithelial neoplasia and in 4 patients (8%) HGIN or Barrett's carcinoma (BC) was revealed. Inter-observer agreement between the general and specialized pathologists for the diagnosis of LGIN was poor (kappa = - 0.17) and good between both of the specialized pathologists (kappa = 0.69). Patients with HGIN/BC were treated by endoscopic resection or surgery. In patients with LGIN, ablative therapy was performed. Complete response was achieved in 25 patients, but 3 patients developed HGIN and 1 patient developed BC after 10+/-3.6 months.

CONCLUSIONS

BE with LGIN is difficult to diagnose. Inter-observer variability is unacceptable between general and specialized pathologists and therefore when diagnosing LGIN a second opinion should always be sought by a specialized GI pathologist. Ablation therapy seems to be effective in patients with LGIN, but follow-up endoscopies are necessary to detect metachronous neoplasia.

Endoscopic therapy of dysplasia and early-stage cancers of the esophagus

Endoscopic treatments have become a viable alternative for some patients with early-stage esophageal neoplasia. Although esophagectomy remains the standard of care for high-grade dysplasia and superficial cancers, surgical morbidity and mortality may deter patients who are medically unfit or reluctant to undergo surgery. Photodynamic therapy (PDT) and endoscopic mucosal resection (EMR) are the best-studied nonsurgical approaches at present. PDT has been reported to eradicate high-grade dysplasia (HGD) and early Barrett's cancers at rates ranging from 75% to 100% and 17% to 100%, respectively, and a recent randomized controlled trial confirmed that PDT may prevent progression of HGD to cancer. Complete remission rates greater than 90% have also been reported with EMR and other mucosa-ablating interventions, although recurrence rates necessitate close endoscopic surveillance and retreatment in some patients. In addition to PDT and EMR, several emerging endoscopic treatment options for superficial esophageal neoplasia may provide attractive alternatives to surgery.

Acetic acid allows effective selection of areas for obtaining biopsy samples in Barrett's esophagus

OBJECTIVE

The aim of this study was to determine whether macroscopic changes resulting from acetic acid application on the surface of columnar-lined esophagus allow regular, nonmagnifying, endoscopic identification of areas presenting dysplasia and/or cancer in Barrett's esophagus.

PATIENTS AND METHODS

A total of 100 patients (mean age, 53 years; range, 27-86 years) under surveillance because of short-segment (n=71) and long-segment (n=29) Barrett's esophagus, with no alterations of columnar-lined esophagus on standard endoscopy, were enrolled. After endoscopic examination, 3% acetic acid was sprayed on columnar-lined esophagus. The subsequent appearance of the mucosa was classified as: (1) Normal pattern: uniform reticulum along the entire columnar-lined esophagus. (2) Abnormal pattern: reticulum presenting areas of rough or irregular appearance. Biopsy samples were obtained from areas of normal and abnormal patterns, and the results of the corresponding histological studies were compared. All endoscopies were performed by the same investigator.

RESULTS

The endoscopic appearance, after acetic acid application, corresponded to a normal pattern in 85% of cases and an abnormal pattern in 15%. The percentage of dysplasia and adenocarcinoma in biopsy specimens was significantly higher in patients with rough or irregular areas (86.7%) than in those with normal uniform reticulum (0%) (P< 0.001). Sensitivity for the identification of areas of dysplasia or adenocarcinoma was 100% (95% confidence interval: 71.7-100%). Specificity was 97.7% (95% confidence interval: 91.2-99.6%).

CONCLUSIONS

This prospective study shows that acetic acid test is useful for standard, nonmagnifying, endoscopic detection of dysplasia and cancer in Barrett's esophagus.

Usefulness of magnifying endoscopy with narrow band imaging for the detection of specialized intestinal metaplasia in columnar-lined esophagus and Barrett's adenocarcinoma

BACKGROUND

Barrett's esophagus with specialized intestinal metaplasia (SIM) from columnar-lined esophagus is difficult to distinguish with routine endoscopy.

OBJECTIVE

To examine the values of fine mucosal patterns and the capillary patterns observed by magnifying endoscopy with narrow band imaging (MENBI) for the detection of SIM in columnar-lined esophagus and superficial Barrett's adenocarcinoma. We also undertook a histologic investigation regarding whether the capillary pattern observed by MENBI corresponds to the 3-dimensional (3D) structure of the capillary as depicted by using a confocal laser-scanning microscope (CLSM).

DESIGN

To compare the findings of MENBI, at 217 sites of columnar-lined esophagus, with histologic findings. Capillaries of the superficial mucosal layer were observed and were analyzed by 3D with a CLSM in 45 biopsied specimens.

PATIENTS

Fifty-eight patients, including 4 with superficial Barrett's adenocarcinoma.

SETTING

Jikei University Hospital, Tokyo, Japan.

RESULTS

Upon observation, all 6 adenocarcinoma sites were classified as irregular patterns in both the fine mucosal patterns and capillary patterns. The most characteristic endoscopic patterns of SIM were revealed to be the cerebriform fine mucosal pattern (sensitivity, 56%; specificity, 79%; odds ratio, 4.78) and ivy- or deoxyribonucleic acid (DNA)-like capillary pattern (sensitivity, 77%; specificity, 94%; odds ratio, 51.6). The addition of capillary patterns to fine mucosal patterns improved the accuracy of diagnosing SIM (P < .0001).

CONCLUSIONS

MENBI was able to precisely visualize the structure of capillaries in the superficial mucosal layer. The addition of capillary patterns to fine mucosal patterns appeared to improve the diagnostic value for detecting SIM and superficial Barrett's adenocarcinoma upon observation by MENBI.

Management of high-grade dysplasia in patients with Barrett's esophagus

In the past, the standard management for patients with high-grade dysplasia in Barrett's esophagus was esophagectomy, in part on the basis of the assumption that the patient was likely to harbor an undetected carcinoma. With better awareness of the safety of surveillance protocols, improved prospective surveillance, and experience with cohorts of patients in whom incident early lesions unassociated with invasive carcinomas are detected, endoscopic techniques for treatment of Barrett-associated neoplasia have become excellent alternatives to esophagectomy for appropriately selected patients. Emerging endoscopic techniques offer an opportunity for better evaluation of patients with Barrett's-associated neoplasia.

Molecular Biologic Assessment of Barrett's Esophagus

BE is a prevalent condition often associated with long-standing and severe GERD. BE harbors the cellular and genetic substrates necessary for subsequent development of cancer in a subset of patients. Epidemiologically, BE patients with high-grade dysplasia exhibits the highest risk for cancer. Until recently, little was understood about which BE patients with no or low-grade dysplasia may also be at risk for progression to neoplasia. The presence of p53 abnormalities in Barrett's mucosae (such as 17p LOH) and also DNA abnormalities (such as aneuploidy and increased tetraploid fractions) detectable on flow cytometry may be useful in identifying those patients with BE who are at the highest risk for cancer development. New diagnostic modalities and therapeutic strategies continue to evolve, and will require careful clinical validation.

Comparison of methylene blue-directed biopsies and four-quadrant biopsies in the detection of high-grade intraepithelial neoplasia and early cancer in Barrett's oesophagus

BACKGROUND

Barrett's oesophagus embodies the risk of malignant transformation. High-grade intraepithelial neoplasia and early cancer in Barrett's oesophagus are often discrete or macroscopically occult lesions and show a patchy distribution and therefore, directed biopsies in combination with four-quadrant random biopsies are the gold standard for surveillance.

AIMS

The aim of this prospective study was to compare methylene blue staining and random biopsies in patients with early Barrett's neoplasia.

PATIENTS AND METHODS

Eighty-six patients (mean age 65+/-8 years) with histologically proven but macroscopically in evident high-grade intraepithelial neoplasia (n=17) or early cancer in Barrett's oesophagus (n=69) on HR-endoscopy with all together 98 lesions, were included. In the first step, four-quadrant random biopsies were taken during routine endoscopy (group I). In a second step, staining was performed with a 0.5% solution of methylene blue with a spray catheter. Biopsies of focal areas with decreased stain, heterogeneity of stain or absence stain were taken (group II).

RESULTS

In 75/86 patients, high-grade intraepithelial neoplasia or early cancer in Barrett's oesophagus could be diagnosed in the methylene blue group while 56 patients were determined in the random biopsies group (P=0.053). High-grade intraepithelial neoplasia or early cancer was diagnosed in significantly more methylene blue-directed biopsies (80.9% versus 26.4%, P<0.005) and also significantly more lesions could be identified in the methylene blue group (96/98; 98%) while in the random biopsies group only 58/98 lesions (59%) could be localised (P<0.05). When methylene blue was used (1217 versus 562, P<0.0001), the average number of specimens taken with methylene blue per patient was about half of that with random biopsy (6.5 versus 14.1, P<0.0001).

CONCLUSIONS

Chromoendoscopy with methylene blue diagnosed significantly more patients and lesions with intraepithelial neoplasia or early cancer in Barrett's oesophagus compared to random biopsies. In addition, significantly less biopsies were needed with methylene blue compared to random biopsies. The use of methylene blue-directed biopsies appears to improve the detection of intraepithelial neoplasia and early cancer in Barrett's oesophagus.

Endoscopic video-autofluorescence imaging followed by narrow band imaging for detecting early neoplasia in Barrett's esophagus

BACKGROUND

Video-autofluorescence imaging (AFI) and narrow band imaging (NBI) are new endoscopic techniques that may improve the detection of high-grade intraepithelial neoplasia (HGIN) in Barrett's esophagus (BE). AFI improves the detection of lesions but may give false-positive findings. NBI allows for detailed inspection of the mucosal and (micro)vascular patterns, which are related to HGIN.

OBJECTIVE

A proof-of-principle study to combine AFI and NBI to improve the detection of HGIN and to reduce false-positive findings.

DESIGN

Cross-sectional study of consecutive eligible patients.

SETTING

Single-center.

PATIENTS

Twenty patients with BE with suspected or endoscopically treated HGIN were investigated with 2 prototype imaging systems: AFI (inspection with high-resolution videoendoscopy and autofluorescence imaging for detection of lesions) and NBI (for detailed inspection of mucosal and vascular patterns of identified lesions). Lesions were sampled for histopathologic evaluation.

MAIN OUTCOME MEASUREMENTS

The positive predictive value of AFI alone and of AFI-NBI for detecting HGIN and the reduction of false-positive findings because of the use of NBI.

RESULTS

All of the 28 lesions with HGIN were identified with AFI. Seventeen were identified with white light (61%). Forty-seven suspicious lesions were detected with AFI: 28 contained HGIN (60%) and 19 were false positive (40%). With NBI, 25 of the true-positive lesions had definitely suspicious patterns, and 3 had dubiously suspicious patterns. Of the 19 false positives, 14 were not suspicious on NBI. The false-positive rate, therefore, was reduced from 40% to 10%. Low-grade dysplasia was found in 4 of the remaining 5 false positives. All of the 14 patients with HGIN were identified by AFI-NBI (sensitivity 100%).

LIMITATIONS

Uncontrolled study in high-risk patients.

CONCLUSIONS

This proof-of-principle study confirms that AFI can be used as a red-flag technique to detect suspicious lesions. With NBI, detailed inspection of the surface patterns can be performed. This combination may increase the accuracy of detecting HGIN in BE.

Randomized crossover study that used methylene blue or random 4-quadrant biopsy for the diagnosis of dysplasia in Barrett's esophagus

BACKGROUND

Barrett's esophagus is generally accepted to be a premalignant condition. Previous studies have suggested the use of methylene blue (MB) chromoendoscopy to aid the identification of dysplasia in Barrett's esophagus surveillance programs, but a recent study has raised the concern that MB might induce oxidative damage of DNA.

OBJECTIVE

The aim of this study was to compare MB directed biopsies (MBDB) with our current standard, which is random 4 quadrant biopsies (RB).

DESIGN

A randomized prospective crossover study.

SETTING

Single center.

PATIENTS

Patients with a diagnosis of dysplasia identified in Barrett's esophagus within a 2-year period before entering the study.

INTERVENTIONS

Either 4 random quadrant biopsies taken every 2 cm through the length of the Barrett's esophagus or MBDB from unstained or heterogenously stained mucosa.

MAIN OUTCOME MEASUREMENTS

The number of patients with a diagnosis of dysplasia by each intervention.

LIMITATIONS

Thirty-six percent of eligible patients declined the invitation to participate.

RESULTS

Thirty patients completed the crossover study. The median length of Barrett's esophagus was 5 cm (interquartile range [IQR] 3-9 cm). At baseline histology, grades were as follows: 17 low-grade dysplasia (LGD), 3 high-grade dysplasia (HGD), and 10 no dysplasia. At completion, there were 10 LGD, 8 HGD, and 12 no dysplasia. Overall, dysplasia was identified in 17 of 18 patients by RB and in 9 of 18 by MBDB (McNemar test, p = 0.02).

CONCLUSIONS

Our study showed MBDB to be significantly less sensitive in detecting dysplasia than RB in Barrett's esophagus. Hence, we discourage its use during routine surveillance of Barrett's esophagus.

Ablation of nonneoplastic Barrett's mucosa using argon plasma coagulation with concomitant esomeprazole therapy (APBANEX): a prospective multicenter evaluation

BACKGROUND

Complete reversal of Barrett's epithelium (BE) achieved by treatment with argon plasma coagulation (APC) is variable. The aim of this prospective study was to evaluate the effectiveness of high-power APC in a multicenter trial.

METHODS

In seven study centers, 60 patients (mean age 57, range 27-77) with nonneoplastic BE (length 1-8 cm) were recruited for treatment with high-power APC (90 W) in combination with esomeprazole 80 mg/day. Video endoscopy, chromoendoscopy, and four-quadrant biopsies (4QB) were carried out during baseline endoscopy and regular intervals. The effect of ablation was classified as complete remission (CR), partial remission, or minor response.

RESULTS

Fifty-one of the 60 patients completed ablation therapy. Three patients were lost to follow-up (FU). After a mean of 2.6 APC sessions (range 1-5) and a mean FU of 14 months (range 12-32), CR was achieved in 37 of 48 patients (77%). Major complications occurred in five of 51 patients (9.8%).

CONCLUSIONS

Complete ablation of BE can be achieved in a high percentage of patients even in a multicenter design using high-power APC. However, APC has a relevant morbidity. Therefore, ablation of nonneoplastic BE cannot be recommended generally because incidence of cancer in BE is low.

Acetic acid-guided biopsies after magnifying endoscopy compared with random biopsies in the detection of Barrett's esophagus: a prospective randomized trial with crossover design

BACKGROUND

In contrast to standard video endoscopy, magnifying endoscopy after local acetic acid application enables recognition of mucosal surface architecture.

OBJECTIVE

To investigate the diagnostic yield of magnifying endoscopy with acetic acid-targeted biopsies compared to random, 4-quadrant biopsies.

DESIGN

Prospective randomized trial (ratio 1:1) with crossover design.

SETTING

Two referral hospitals in Germany.

PATIENTS

Thirty-one patients with Barrett's esophagus or visible columnar-lined lower esophagus.

INTERVENTIONS

Patients were randomized to undergo either standard video endoscopy with 4-quadrant biopsies or magnifying endoscopy in conjunction with acetic acid application. All patients were re-examined 14 days after the initial endoscopy with the corresponding procedure.

MAIN OUTCOME MEASUREMENTS

Primary outcome analysis (per protocol and per biopsy) was the histological proof of Barrett's epithelium. Secondary outcome analysis was the correlation between the surface architecture and the presence of Barrett's epithelium and the needed number of biopsies to confirm Barrett's epithelium for the 2 different procedures.

RESULTS

Magnifying endoscopy enabled the prediction of Barrett's epithelium with a sensitivity of 100% and a specificity of 66%, respectively (accuracy 83.8%). Acetic acid-guided biopsies obtained a significantly higher percentage of tissues containing SCE (78%; 188/241) compared to random biopsies (57%; 159/280).

LIMITATIONS

No data on the diagnosis of Barrett's dysplasia.

CONCLUSION

Magnifying endoscopy with acetic acid-guided biopsies is superior to standard video endoscopy with random biopsies, and the number of biopsies needed to confirm Barrett's epithelium is half as much when compared to random biopsies.

[A review of the clinical application of dyes in gastrointestinal chromoendoscopy, and their magistral formulation]

OBJECTIVE

To review the drug compounding of dyes employed in chromoendoscopy, and their clinical effectiveness.

METHOD

A literature search in Medline, Cochrane Library, and Micromedex was carried out with the term chromoendoscopy as a keyword, and the search was then repeated for each dye found in association with the term endoscopy. A number of monographs, scientific journals, and references quoted in selected papers were also reviewed. Papers collected were then classified according to their methodology.

RESULTS

Ninety-six references were found, their original article being recovered for only 57 of these - 13 clinical trials, 21 case series, and 11 reviews. References were found for 7 dyes. Main indications, evidence of effectiveness, administration route, and drug formulation are described for each dye.

CONCLUSIONS

The number of papers involved is high, but their accessibility is limited. Evidence is overall scarce, but high in cases such as methylene blue for Barrett s esophagus, lugol in the detection of esophageal carcinoma, and indigo carmine for colonic hyperplastic polyp differentiation. Drug compounding is rather simple, but scarcely developed.

Diagnostic accuracy of magnifying chromoendoscopy with detection of intestinal metaplasia and dysplasia using acetic acid in Barrett's esophagus

OBJECTIVES

Endoscopy with systematic randomized biopsies aims to improve the detection of intestinal metaplasia (IM) and dysplasia in Barrett's esophagus (BE). Magnifying chromoendoscopy with alcoholic acetic acid might allow directed biopsies to improve detection of IM and dysplasia.

PATIENTS AND METHODS

Twenty-eight patients were studied with magnifying chromoendoscopy (Optical power zoom x 115, alcoholic acetic acid). Endoscopy biopsies were performed on one or several zones of BE chosen randomly, for which the chromoendoscopic pattern was determined according to Guelrud's classification.

RESULTS

Among seventy-two biopsies, the agreement between magnifying chromoendoscopy and histology and the positive predictive value of the association of patterns III and IV for the diagnosis of IM were 72.4%; sensibility and specificity were respectively 95.5% and 42.9%. The diagnostic accuracy was 75%. Among the six biopsies that showed high-grade dysplasia, three were suspected because of two particular patterns: local loss of ridged cerebriform pattern due to the disorganization of the mucosal folds and hypervascularization of the mucosa.

CONCLUSION

Magnifying chromoendoscopy with acetic acid allows targeted biopsies of the IM in BE and may help to detect high-grade dysplasia.

Evaluation of modified crystal violet chromoendoscopy procedure using new mucosal pit pattern classification for detection of Barrett's dysplastic lesions

BACKGROUND

Pit pattern diagnosis is important for endoscopic detection of dysplastic Barrett's lesions, though using magnification endoscopy can be difficult and laborious. We investigated the usefulness of a modified crystal violet chromoendoscopy procedure and utilised a new pit pattern classification for diagnosis of dysplastic Barrett's lesions.

METHODS

A total of 1,030 patients suspected of having a columnar lined oesophagus were examined, of whom 816 demonstrated a crystal violet-stained columnar lined oesophagus. The early group of patients underwent 0.05% crystal violet chromoendoscopy, while the later group was examined using 0.03% crystal violet with 3.0% acetate. A targeted biopsy of the columnar lined oesophagus was performed using crystal violet staining after making a diagnosis of closed or open type pit pattern with a newly proposed system of classification. The relationship between type of pit pattern and histologically identified dysplastic Barrett's lesions was evaluated.

RESULTS

Dysplastic Barrett's lesions were identified in biopsy samples with an open type pit pattern with a sensitivity of 96.0%. Further, Barrett's mucosa with the intestinal predominant mucin phenotype was closely associated with the open type pit pattern (sensitivity 81.9%, specificity 95.6%).

CONCLUSIONS

The new pit pattern classification for diagnosis of Barrett's mucosa was found to be useful for identification of cases with dysplastic lesions and possible malignant potential using a crystal violet chromoendoscopic procedure.