Endoscopic surveillance of columnar-lined esophagus: frequency of intestinal metaplasia detection and impact of antireflux surgery

Barrett's Esophagus and Associated Dysplasia

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

Efficacy of Nissen Sleeve Gastrectomy on Mid-term Barrett's Esophagus Regression

INTRODUCTION

Sleeve gastrectomy is the most commonly performed bariatric operation globally. The main complication is GERD. In the medium term, it can increase the incidence of Barrett's esophagus (BE), which is a risk factor for esophageal adenocarcinoma. Following conventional sleeve gastrectomy, BE is noted in up to 16% of patients postoperatively. Recently, Nissen sleeve gastrectomy (NSG) has been shown to reduce the frequency of postoperative GERD compared to conventional sleeve gastrectomy. This study aims to evaluate the impact of NSG on the incidence and remission of BE in the long term.

MATERIAL AND METHOD

This bicentric retrospective study included 692 patients who received NSG from September 2013 to July 2021. All patients underwent preoperative upper GI endoscopy and were then scheduled to receive upper GI endoscopy between 1 and 2 years and then between 3 and 5 years postoperatively. BE was systematically confirmed by biopsies.

RESULTS

Seventy-four patients had endoscopic suspicion of BE, which was confirmed on 54/692 patients by histology. The BE lesions consisted of 18.5% intestinal metaplasia and 75.9% fundal metaplasia. Among these 54 patients, 38 underwent endoscopic investigation within 2 years postoperatively. The biopsies showed healed BE in 25/38 patients (64.1%). At 5 years, two patients had proven BE. Concerning the incidence of BE post NSG: 234 performed the follow-up endoscopy within 2 years. The incidence of de novo BE is nil.

CONCLUSION

The NSG is associated with healing of known BE in approximately two-thirds of patients at 2-year follow-up. This is consistent with the GERD improvement that has been shown with NSG.

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

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

DIAGNOSIS, TREATMENT AND FOLLOW-UP OF BARRETT'S ESOPHAGUS: A SYSTEMATIC REVIEW

BACKGROUND

Barrett's esophagus (BE) is a premalignant condition that raises controversy among general practitioners and specialists, especially regarding its diagnosis, treatment, and follow-up protocols.

OBJECTIVE

This systematic review aims to present the particularities and to clarify controversies related to the diagnosis, treatment and surveillance of BE.

METHODS

A systematic review was conducted on PubMed, Cochrane, and SciELO based on articles published in the last 10 years. PRISMA guidelines were followed and the search was made using MeSH and non-MeSH terms "Barrett" and "diagnosis or treatment or therapy or surveillance". We searched for complete randomized controlled clinical trials or Phase IV studies, carried out with individuals over 18 years old.

RESULTS

A total of 42 randomized controlled trials were selected after applying all inclusion and exclusion criteria. A growing trend of alternative and safer techniques to traditional upper gastrointestinal endoscopy were identified, which could improve the detection of BE and patient acceptance. The use of chromoendoscopy-guided biopsy protocols significantly reduced the number of biopsies required to maintain similar BE detection rates. Furthermore, the value of BE chemoprophylaxis with esomeprazole and acetylsalicylic acid was relevant, as well as the establishment of protocols for the follow-up and endoscopic surveillance of patients with BE based predominantly on the presence and degree of dysplasia, as well as on the length of the follow-up affected by BE.

CONCLUSION

Although further studies regarding the diagnosis, treatment and follow-up of BE are warranted, in light of the best evidence presented in the last decade, there is a trend towards electronic chromoendoscopy-guided biopsies for the diagnosis of BE, while treatment should encompass endoscopic techniques such as radiofrequency ablation. Risks of ablative endoscopic methods should be weighted against those of resective surgery. It is also important to consider lifetime endoscopic follow-up for both short and long term BE patients, with consideration to limitations imposed by a range of comorbidities. Unfortunately, there are no randomized controlled trials that have evaluated which is the best recommendation for BE follow-up and endoscopic surveillance (>1 cm) protocols, however, based on current International Guidelines, it is recommended esophagogastroduodenoscopy (EGD) every 5 years in BE without dysplasia with 1 up to 3 cm of extension; every 3 years in BE without dysplasia with >3 up to 10 cm of extension, every 6 to 12 months in BE with low grade dysplasia and, finally, EGD every 3 months after ablative endoscopic therapy in cases of BE with high grade dysplasia.

Barrett Esophagus and Intestinal Metaplasia of the Gastroesophageal Junction in Children: A Clinicopathologic Study

OBJECTIVES

Barrett esophagus (BE) and intestinal metaplasia of gastroesophageal junction (IMGEJ) are rare in the pediatric population. This multi-institutional retrospective study evaluated the clinicopathologic characteristics and natural history of BE and IMGEJ in children.

METHODS

Data from 20 BE patients (70% boys, mean age: 14.9 years) and 17 IMGEJ patients (71% boys, mean age: 14 years) were retrospectively obtained from chart review. Endoscopic and pathologic findings from index and follow-up endoscopies were analyzed.

RESULTS

Most patients (70% BE and 59% IMGEJ) had underlying conditions which put them at risk for gastroesophageal reflux disease. Increased body mass index (BMI) was observed in patients without underlying conditions (BE: 30.1 ± 9.8; IMGEJ: 23.9 ± 6.3) compared with those with underlying conditions (BE: 19.6 ± 7.8; IMGEJ: 16.4 ± 2.1) (BE, P = 0.02; IMGEJ, P = 0.01). Incomplete intestinal metaplasia (IM) was the predominant histology seen in BE (80%) and IMGEJ patients (75%). Dysplasia and malignancy were not identified in the initial and follow-up biopsies. Concurrent gastric biopsies showed various findings (79% BE and 40% IMGEJ were normal), with 1 IMGEJ patient showing coexisting gastric IM (7%). Follow-up in 12 BE patients (mean follow-up time 51.6 months) showed 100% persistent endoscopic disease and 58% persistent IM histologically. Three of 6 IMGEJ patients (mean follow-up time 24 months) demonstrated endoscopic and histologic features consistent with BE on subsequent procedures. Moreover, a subset of BE (57%) and IMGEJ patients (67%) who underwent endoscopy before initial diagnosis showed nongoblet columnar mucosa above the anatomic gastroesophageal junction.

CONCLUSIONS

Increased BMI may be a risk factor for BE and IMGEJ in pediatric patients without underlying conditions. Nongoblet columnar metaplasia and IMGEJ might represent incomplete forms of BE. Our data suggest that these patients should be closely monitored.

Esophagus and Gastrointestinal Junction Tumors

Esophageal squamous cell carcinoma and adenocarcinoma account for 95% of all esophageal malignancies. The rates of esophageal adenocarcinoma have increased in Western countries, making it the predominant type of esophageal cancer. Treatment of both types of cancer has transformed to a more minimally invasive approach, with endoscopic methods being used for superficial cancers and more frequent use of video-assisted and laparoscopic modalities for locally advanced tumors. The current National Comprehensive Cancer Network guidelines advocate a trimodal approach to treatment, with neoadjuvant chemoradiation and surgery for locally advanced cancers.

Laparoscopic Hernia Repair and Fundoplication for Gastroesophageal Reflux Disease

Antireflux surgery is challenging, and has become even more challenging with the introduction of alternative endoscopic and laparoscopic options for patients with gastroesophageal reflux disease (GERD). The Nissen fundoplication remains the gold standard for the durable relief of GERD symptoms and esophagitis. All antireflux procedures have a failure rate, and it is important to minimize factors that are associated with failure. The selection of patients for antireflux surgery as well as the choice of the procedure requires a thorough understanding of esophageal physiology and the pros and cons of various options.

Long-term (15-year) objective evaluation of 150 patients after laparoscopic Nissen fundoplication

INTRODUCTION

Laparoscopic Nissen fundoplication is the preferred operative treatment for patients with gastroesophageal reflux disease. The most recent published results only refer to clinical evaluations and few discuss objective measurements. Our purpose was to determine the late results of laparoscopic Nissen fundoplication, performing clinical, endoscopic, histologic, and functional studies.

MATERIAL AND METHODS

A total of 179 patients were included in a prospective study. All had gastroesophageal reflux disease symptoms of at least 5-year duration, daily dependence on proton pump inhibitors, and a type I hiatal hernia less than 5 cm. Exclusion criteria included Barrett's esophagus, hiatal hernia >5 cm, failed antireflux surgery, and obesity (body mass index >30). We performed a radiologic study, 3 or more endoscopic procedures with biopsy samples of the antrum and esophagogastric junction, esophageal manometry, and 24-hour pH monitoring.

RESULTS

We found that 4 patients (2.2%) died 3-4 years after operation from nonoperatiove reasons. A total of 25 patients (14%) were lost to follow-up, and 150 patients (83.8%) submitted to late objective evaluations (15 years). Visick I-II symptoms were observed in 79.3% and III-IV (failures) in 20.7%. Endoscopy showed a normal positioning of the esophagogastric junction in the Visick I-II patients and a type III cardia or hiatal hernia with erosive esophagitis in Visick III-IV patients. Short-segment Barrett's esophagus developed in 5.3% of patients. Lower esophageal sphincter pressure remained increased over the preoperative value in all groups. The 24-hour pH monitoring also was decreased over the preoperative value in Visick I-II patients but showed no significant change in Visick III-IV patients. Carditis at the esophagogastric junction regressed to fundic mucosa in 50% of Visick I-II patients.

CONCLUSION

Laparoscopic Nissen fundoplication produces control of symptoms in 80% of patients late (up to 15 years) after surgeries corroborated by endoscopic, histologic examinations, and functional studies. It is essential to perform these objective evaluations to demonstrate the "antireflux effect" after laparoscopic Nissen fundoplication.

Carditis: a relevant marker of gastroesophageal reflux disease. Data from a prospective central European multicenter study on histological and endoscopic diagnosis of esophagitis (histoGERD trial)

The columnar-lined mucosa at the gastroesophageal junction may contain an inflammatory infiltrate, commonly referred to as carditis (or cardia gastritis). The etiology of carditis is not entirely clear since published data are conflicting. Some authors believe it to be secondary to gastroesophageal reflux disease (GERD) and others to Helicobacter pylori gastritis. This prospective study aims at clarifying the relationship between carditis and the histological, clinical, and endoscopic findings of GERD, in a large cohort of individuals negative for H. pylori infection. Eight hundred and seventy-three individuals (477 females and 396 males, median age 53 years) participated in this study. Biopsy material was systematically sampled from above and below the gastroesophageal junction. Reflux-associated changes of the esophageal squamous epithelium were assessed according to the Esohisto consensus guidelines. Grading of carditis was performed according to the Updated Sydney System, known from the histological evaluation of gastritis. In total, 590 individuals (67.5%) had chronic carditis. Of these, 468 (53.6%) had mild chronic inflammation, with 321 individuals (68.6%) showing no or minimal changes on endoscopic examination (Los Angeles Categories N and M). The presence of chronic carditis was associated with several GERD-related parameters of the esophageal squamous epithelium (P < 0.0001), and data retained statistical significance even when analysis was restricted to individuals with mild chronic carditis and/or endoscopically normal mucosa. Chronic carditis was also associated with the presence of intestinal metaplasia (P < 0.0001). In addition, chronic carditis had a statistically significant association with patients' symptoms of GERD (P = 0.0107). This observation remained valid for mild chronic carditis in all patients (P = 0.0038) and in those with mild chronic carditis and normal endoscopic mucosa (P = 0.0217). In conclusion, chronic carditis appears to be the immediate consequence of GERD, correlating with patients' symptoms and endoscopic diagnosis. These results are valid in individuals with nonerosive reflux disease, which indicates a higher sensitivity of histological diagnosis. Our findings may impact the routine assessment of reflux patients.

Histology of Barrett's Metaplasia: Do Goblet Cells Matter?

This review has provided a summary of the biology of goblet cell metaplasia in CLE as it pertains to BE. Goblet cells are terminally differentiated nonproliferative cells that have many overlapping histochemical characteristics with mucinous columnar cells and pseudogoblet cells. There is an abundance of evidence that suggests that use of goblet cells as a biomarker of BE, and its progression to malignancy, is problematic. Some of these limitations include the fact that the background non-goblet epithelium in most patients with CLE is biologically intestinalized and contains molecular abnormalities similar to goblet cell CLE, goblet cells fluctuate with time and decrease in number with progression of neoplasia, and pathologists have problems with interpretation, and distinction, of goblet cells from other types of cells in the esophagus. Sampling error results in sensitivity and specificity issues that limit its positive predictive value. Goblet cells are fewest in number in the same population of patients with CLE that are hardest to detect endoscopically (i.e., those with short or ultrashort CLE). Nevertheless, the risk of cancer in patients with short-segment BE, a condition difficult to distinguish from the stomach, is very low regardless of the presence or absence of goblet cells so it is unclear what the role of goblet cells is in these patients as a biomarker. Nevertheless, if the answer to the following question, "Would you as a gastroenterologist recommend surveillance for a patient with clear endoscopic evidence of CLE, particularly if it is ≥ 3 cm in length, but in which goblet cells were not reported to be present by the pathologist," is yes, then the US requirement for goblet cells as part of the criteria for "BE" is superfluous.

Early Barrett esophagus-related neoplasia in segments 1 cm or longer is always associated with intestinal metaplasia

The assumption that intestinal metaplasia is a prerequisite for intraepithelial neoplasia/dysplasia and adenocarcinoma in the distal esophagus has been challenged by observations of adenocarcinoma without associated intestinal metaplasia. This study describes our experience of intestinal metaplasia in association with early Barrett neoplasia in distal esophagus and gastroesophageal junction. We reviewed the first endoscopic mucosal resection of 139 patients with biopsy-proven neoplasia. In index endoscopic mucosal resection, 110/139 (79%) cases showed intestinal metaplasia. Seven had intestinal metaplasia on prior biopsy specimens and three had intestinal metaplasia in subsequent specimens, totaling 120/139 (86%) patients showing intestinal metaplasia at some point supporting the theory of sampling error for absence of intestinal metaplasia in some cases. Those without intestinal metaplasia (13%) were enriched for higher stage disease (T1a Stolte m2 or above) supporting the assertion of obliteration of intestinal metaplasia by the advancing carcinoma. All cases of intraepithelial neoplasia and T1a Stolte m1 carcinomas had intestinal metaplasia (42/42). The average density of columnar-lined mucosa showing goblet cells was significantly less in shorter segments compared to those ≥3 cm (0.31 vs 0.51, P=0.0304). Cases where segments measured less than 1 cm were seen in a higher proportion of females and also tended to lack intestinal metaplasia. We conclude that early Barrett neoplasia is always associated with intestinal metaplasia; absence of intestinal metaplasia is attributable to sampling error or obliteration of residual intestinal metaplasia by neoplasia and those with segments less than 1 cm show atypical features for Barrett-related disease (absent intestinal metaplasia and female gender), supporting that gastroesophageal junction adenocarcinomas are heterogeneous.

Histologic Features Associated With Columnar-lined Esophagus in Distal Esophageal and Gastroesophageal Junction (GEJ) Biopsies From GERD Patients: A Community-based Population Study

There are inherent problems with the endoscopic and pathologic criteria for columnar-lined esophagus (CLE). Furthermore, the clinical and biological significance of an irregular squamocolumnar junction (SCJ) is unclear. The aim of this study was to evaluate the association between histologic features in SCJ biopsies and CLE and to gain insight into the significance of an irregular SCJ. The study was a cross-sectional analysis of 2176 mucosal biopsies of the SCJ from 544 patients in a large prospective community clinic-based study of gastroesophageal reflux disease in Washington State. Biopsy samples were evaluated blindly for a wide variety of histologic features, such as the presence and type of mucosal glands, submucosal glands and ducts, goblet cells, multilayered epithelium (ME), inflammation, and buried columnar epithelium. Histologic findings were correlated with the endoscopic findings (normal Z-line, irregular Z-line, or CLE) and evaluated by logistic regression and receiver operating characteristic analysis.Five histologic features were associated with CLE: pure mucous glands, ME, presence of goblet cells, ≥50% of crypts with goblet cells, and buried columnar epithelium. Pure oxyntic glands were inversely associated with CLE. The features most strongly related to CLE included biopsies with ≥50% of crypts with goblet cells, ME, and mucosal gland type (area under the curve=0.71; 95% confidence interval=0.66-0.76). Patients with an irregular Z-line were histologically similar to those with CLE. Certain histologic features in biopsies of the SCJ are associated with the presence of CLE. Irregularity of the Z-line is probably indicative of ultrashort segment CLE, instead of being a potential variation of normal.

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

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

The immunophenotypic relationship between the submucosal gland unit, columnar metaplasia and squamous islands in the columnar-lined oesophagus

AIMS

To characterize the immunophenotypic relationship between the squamous and the glandular compartments in the oesophagus of patients with columnar-lined oesophagus (CLO).

METHODS AND RESULTS

Eight tissue blocks from three oesophageal resection specimens from patients who underwent oesophagectomy for adenocarcinoma of the oesophagus were selected for immunohistochemical analysis. The markers of intestinal differentiation [CK20, CDX2 and MUC2] were all expressed in the expected pattern, solely in the glandular compartment of the resection specimens. CK4, CK17 and lysozyme were expressed in both the glandular and the squamous compartments. In addition, CK17 expression was found on both the squamous and glandular margins of the squamocolumnar transformation zones and in the submucosal gland (SMG) intraglandular and excretory ducts.

CONCLUSIONS

There is an immunophenotypic relationship between the squamous and the glandular compartments of the CLO, with expression of lysozyme, CK4 and CK17 in both squamous and columnar cells. These overlapping immunophenotypes indicate similar differentiation paths, and link the SMG unit with the columnar metaplasia and the neosquamous islands in CLO. Our findings support the theory of a cellular origin of CLO and neosquamous islands from the SMG unit.

Optimizing Patient Selection and Outcomes for Surgical Treatment of GERD and Achalasia

OPINION STATEMENT

Gastroesophageal reflux disease is a common disorder in the United States and other western countries. In addition to troublesome symptoms, this condition is associated with impaired quality of life and the potential for disease progression to esophageal adenocarcinoma. Acid suppression medications are extremely effective for the relief of heartburn symptoms, but don't address the physiologic derangements that cause reflux. The goal of an antireflux procedure is to correct these defects and abolish the dietary and lifestyle compromises that accompany medical therapy for gastroesophageal reflux. The Nissen fundoplication has a long and well-established track record and new options such as the LINX magnetic sphincter augmentation device allow correction of reflux with fewer side-effects than a fundoplication in appropriate patients. These options should be considered in patients incompletely satisfied on medical therapy and in those with risk factors for disease progression. The role of these therapies in patients with gastroesophageal reflux disease will be reviewed in this chapter. Achalasia is an uncommon motility disorder of the esophagus that leads to profound dysphagia symptoms and greatly impaired alimentary satisfaction. Pneumatic dilation offers an endoscopic approach to the management of these patients, but often requires repeated dilatations due to the inconsistent disruption of the lower esophageal sphincter with this technique. An alternative is a laparoscopic Heller myotomy, which offers precise division of the muscle of the lower esophageal sphincter, but requires incisions and lifestyle restrictions while healing. A new therapy, per-oral endoscopic myotomy, allows the precise division of the lower esophageal sphincter muscle as in a laparoscopic myotomy, but is done endoscopically with no external incisions. The role of these therapies in patients will be reviewed in this chapter.

Barrett's oesophagus: treatment with surgery

Barrett's oesophagus develops as a consequence of gastro-oesophageal reflux disease and may progress to oesophageal adenocarcinoma. Antireflux surgery is an option for patients with reflux disease, but the efficacy and impact on the natural history of disease in patients with Barrett's oesophagus is controversial. This review addresses the existing data on these important issues.

Barrett's oesophagus diagnostic criteria: endoscopy and histology

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

Hyperplasia of the submucosal glands of the columnar-lined oesophagus

AIM

To evaluate the presence of multi-layered epithelium (ME) and to compare the distribution, size and morphology of the oesophageal submucosal glands (SMG) beneath reflux exposed metaplastic columnar mucosa with those of normal squamous epithelium in patients with columnar-lined oesophagus (CLO).

METHODS AND RESULTS

In eight oesophageal resection specimens, the SMG of the metaplastic segments were significantly larger than those in the squamous segments of patients with CLO (0.81 versus 0.56 mm(2) , P = <0.001). There was an accumulation of SMG close to the neosquamocolumnar junction (NSCJ), as indicated by a higher median frequency of SMG (0.080 SMG/mm) compared with that of the squamous (0.013 SMG/mm) and metaplastic segments (0.031 SMG/mm) (P = 0.022). The frequency of ME was significantly higher in the metaplastic compared with the normal squamous segments (1/158 mm and 1/341 mm, respectively, P = 0.028) and ME was found almost exclusively (96%) in direct connection with the excretory ducts of SMG.

CONCLUSIONS

Hyperplasia of SMG in the metaplastic segment, accumulation of SMG near the NSCJ, the presence of ME in connection with the excretory ducts of SMG and metaplasia are all reflux-induced morphological changes, possibly induced by stimulation of progenitors in the excretory ducts of the SMG.

[Comparison of surgical patients with gastroesophageal reflux disease and Barrett's esophagus]

INTRODUCTION

Barrett's esophagus (BE) is the only known precursor of adenocarcinoma occuring in the lower third of the esophagus. According to statistics, severity and elapsed time of gastroesophageal reflux disease (GERD) are major pathogenetic factors in the development of Barrett's esophagus.

PATIENTS AND METHODS

In a retrospective study between 2001 and 2008, we compared the preoperative results (signs and sympthoms, 24 hour pH manometry, esophageal manometry, Bilitec) and treatment efficacy of 176 GERD patients and 78 BE patients, who have undergone laparoscopic Nissen procedure for reflux disease.

RESULTS

The two groups of patients had similar demographic features, and elapsed time of reflux sympthoms were also equal. Both groups were admitted for surgery after a median time of 1.5 years (19.87 vs. 19.20 months) of ineffective medical (proton pump inhibitors) treatment. Preoperative functional tests showed a more severe presence of acid reflux in the BE group (DeMeester score 18.9 versus 41.9, p < 0.001). On the other hand, mano-metry - despite confirming lower esophageal sphincter (LES) damage - did not show difference between the two groups (12.10 vs. 12.57 mmHg, p = 0.892). We did not experience any mortality cases with laparoscopic antireflux procedures, although in two cases we had to convert during the operation (1 due to extensive adhesions, and 1 due to injury to the spleen). 3 months after the procedure - according to Visick score - both groups experienced a significant decrease, or lapse in reflux complaints (group I: 73%, group II: 81% of patients), LES functions improved (17.58 vs.18.70 mmHg), and the frequency and exposition of acid reflux decreased (DeMeester score 7.73 vs. 12.72).

CONCLUSION

The severity of abnormal acid reflux occuring parallel with the incompetent function of the damaged LES triggers not only inflammation in the gastroesophageal junction (GEJ), but also metaplastic process, and the development of Barrett's esophagus. Laparoscopic Nissen procedure for reflux disease can further improve outcome among patients with GERD not responding to conservative therapy.

Barrett esophagus: diagnostic challenges

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

Barrett's oesophagus: epidemiology, cancer risk and implications for management

Although endoscopic surveillance of patients with Barrett's oesophagus has been widely implemented, its effectiveness is debateable. The recently reported low annual oesophageal adenocarcinoma risk in population studies, the failure to identify most Barrett's patients at risk of disease progression, the poor adherence to surveillance and biopsy protocols, and the significant risk of misclassification of dysplasia all tend to undermine the effectiveness of current management, in particular, endoscopic surveillance programmes, to prevent or improve the outcomes of patients with oesophageal adenocarcinoma. The ongoing increase in incidence of Barrett's oesophagus and consequent growth of the surveillance population, together with the associated discomfort and costs of endoscopic surveillance, demand improved techniques for accurately determining individual risk of oesophageal adenocarcinoma. More accurate techniques are needed to run efficient surveillance programmes in the coming decades. In this review, we will discuss the current knowledge on the epidemiology of Barrett's oesophagus, and the challenging epidemiological dilemmas that need to be addressed when assessing the current screening and surveillance strategies.

[The Mexican consensus on gastroesophageal reflux disease. Part II]

OBJECTIVE

To update the themes of endoscopic and surgical treatment of Gastroesophageal Reflux Disease (GERD) from the Mexican Consensus published in 2002.

METHODS

Part I of the 2011 Consensus dealt with the general concepts, diagnosis, and medical treatment of this disease. Part II covers the topics of the endoscopic and surgical treatment of GERD. In this second part, an expert in endoscopy and an expert in GERD surgery, along with the three general coordinators of the consensus, carried out an extensive bibliographic review using the Embase, Cochrane, and Medline databases. Statements referring to the main aspects of endoscopic and surgical treatment of this disease were elaborated and submitted to specialists for their consideration and vote, utilizing the modified Delphi method. The statements were accepted into the consensus if the level of agreement was 67% or higher.

RESULTS

Twenty-five statements corresponding to the endoscopic and surgical treatment of GERD resulted from the voting process, and they are presented herein as Part II of the consensus. The majority of the statements had an average level of agreement approaching 90%.

CONCLUSION

Currently, endoscopic treatment of GERD should not be regarded as an option, given that the clinical results at 3 and 5 years have not demonstrated durability or sustained symptom remission. The surgical indications for GERD are well established; only those patients meeting the full criteria should be candidates and their surgery should be performed by experts.

Presence or absence of intestinal metaplasia but not its burden is associated with prevalent high-grade dysplasia and cancer in Barrett's esophagus

Universal agreement on the inclusion of intestinal metaplasia to diagnose Barrett's esophagus (BE) is lacking. Our aim was to determine the association of intestinal metaplasia and its density with the prevalence of dysplasia/cancer in columnar lined esophagus (CLE). Patients with CLE but no intestinal metaplasia (CLE-no IM) were identified by querying the clinical pathology database using SNOMED codes for distal esophageal biopsies. CLE-IM patients were identified from a prospectively maintained database of BE patients. Subsequently, relative risks for prevalent dysplasia and cancer were calculated. Since patients with CLE-no IM are not usually enrolled in surveillance, only prevalent dysplasia/cancer on index endoscopy was analyzed. Goblet cell density and percent intestinal metaplasia were estimated. All biopsy slides were reviewed for dysplasia by two experienced gastrointestinal pathologists. Two hundred sixty-two CLE-IM and 260 CLE-no IM patients were included (age 64±12 vs. 60±11 years, P=0.001; whites 92% vs. 82%, P=0.001; males 99.7% vs. 99.3%, P=NS; CLE length 3.4±3.2 vears 1.4±0.4 cm, P=0.001 and hiatus hernia 64% vs. 56%, P=0.013). The odds of finding low-grade dysplasia and of high-grade dysplasia (HGD)/cancer were 12.5-fold (2.9-53.8, P=0.007) and 4.2-fold (95% CI 1.4-13, P=0.01) higher, respectively, in the CLE-IM group. Reanalysis after controlling for important variables of age, race, and length did not significantly alter the overall results. In CLE-IM group, when patients with high (>50/LPF) versus low goblet cell density (<50/LPF) and <10% versus >10% intestinal metaplasia were compared, the odds of HGD/cancer, OR 1.5 (0.5-4.9, P=0.5) and 1.97 (0.54-7.22), respectively, were not significantly higher. Demonstration of intestinal metaplasia continues to be an essential element in the definition of BE, but its quantification may not be useful for risk stratification of HGD/cancer in BE.

The effect of rabeprazole on LES tone in experimental rat model

INTRODUCTION

Despite adequate treatment with proton pump inhibitors (PPIs), symptoms of gastroesophageal reflux disease (GERD) may remain persistent as well as Barrett's esophagus may emerge. It may be proposed that the relaxant effect of PPIs on the smooth muscles may lead to resistance of symptoms. The aim of this study is to investigate effects of rabeprazole on the lower esophageal sphincter (LES) pressure with a rat model.

MATERIALS AND METHODS

Sixteen rats were grouped as control and treatment groups. After obtaining LES tissues followed by a 60 min equilibration period for stabilization, contractile response to carbachol was obtained by application of single dose of carbachol to have a final concentration of 10(-6) M in the organ bath. After the contractions reached a plateau, concentration-response relationships for rabeprazole were obtained in a cumulative manner in the treatment group.

RESULTS

In the carbachol contracted LES preparations; 1.5 × 10(-6) and 1.5×10(-5) M of rabeprazole caused 6.08% and 11.34% relaxations respectively which were not statistically significant. However, mean integral relaxation value for 4.5 × 10(-5) M of rabeprazole was 17.34% and this relaxation was significant compared with controls.

CONCLUSIONS

In the present study, rabeprazole caused no direct significant change in LES tone in the therapeutic dose range applied to the organ bath. However, rabeprazole at the high dose caused a significant decrease in the LES tone.

[Barrett's esophagus. An update]

Barrett's esophagus (BE), a well-known complication of gastroesophageal reflux disease (GERD), constitutes a precancerous condition for adenocarcinoma of the distal esophagus. The so-called Barrett's carcinoma shows increasing incidences in countries of the western hemisphere; new data, however, indicate that the rise in incidence is not quite as dramatic as previously assumed. The definition of BE is currently changing: despite good reasons for a purely endoscopic definition of BE, goblet cells are still mandatory for this diagnosis in Germany and the USA. Dysplastic changes in the epithelium are the most important risk factor for the development of Barrett's adenocarcinoma and recently dysplasia was subclassified into a more frequent adenomatous (intestinal) and a non-adenomatous (gastric-foveolar) types. The gold standard for diagnosing dysplasia is still H&E staining. The histological diagnosis of dysplasia is still encumbered by a significant interobserver variability, especially regarding the differentiation between low grade dysplasia and inflammatory/reactive changes and the discrimination between high grade dysplasia and adenocarcinoma. Current data, however, show much higher interobserver agreement in endoscopic resection specimens than in biopsies. Nevertheless, the histological diagnosis of dysplasia should be corroborated by an external second opinion because of its clinical consequences. In endoscopic resections of early Barrett's adenocarcinoma, the pathological report has to include a risk stratification for the likelihood of lymphogenic metastases.

Columnar-lined oesophagus without intestinal metaplasia: results from a cohort with a mean follow-up of 7 years

BACKGROUND

The definition of Barrett's oesophagus lacks consensus, particularly the requirement of intestinal metaplasia for diagnosis. Scarce information exists on the prevalence and natural history of columnar-lined oesophagus without intestinal metaplasia.

AIM

To evaluate the demographics and natural history of columnar-lined oesophagus without intestinal metaplasia ≥ 2 cm in length.

METHODS

Patients with columnar-lined oesophagus ≥ 2 cm in length and no intestinal metaplasia in biopsy specimens from two consecutive endoscopies with at least a 1-year interval were prospectively followed. A cohort of Barrett's oesophagus patients was used as a control.

RESULTS

Columnar-lined oesophagus without intestinal metaplasia (n = 15) had a similar gender distribution, reflux symptoms prevalence and length as those of Barrett's oesophagus (n = 205). Patients were significantly younger (28.6 vs. 60 years, P < 0.0001) and accounted for 48% of patients aged <40 years in the two cohorts, but only 1% of those aged >40 years (P < 0.001). Patient distribution in both cohorts in 5 age brackets (0-19, 20-29, 30-39, 40-49, and >50 years) was significantly different, except for patients aged 40-49 years. Intestinal metaplasia was documented in 60% of the cohort after a mean follow-up of 7.1 years.

CONCLUSIONS

Columnar-lined oesophagus without intestinal metaplasia ≥ 2 cm is infrequent in the setting of a systematic biopsy protocol, is associated with a younger age in comparison with Barrett's oesophagus, and appears to be an intermediate step between squamous and intestinal lining of the oesophagus.

Barrett's Esophagus: Emerging Knowledge and Management Strategies

The incidence of esophageal adenocarcinoma (EAC) has increased exponentially in the last 3 decades. Barrett's esophagus (BE) is the only known precursor of EAC. Patients with BE have a greater than 40 folds higher risk of EAC compared with the general population. Recent years have witnessed a revolution in the clinical and molecular research related to BE. However, several aspects of this condition remain controversial. Data regarding the true prevalence of BE have varied widely. Recent studies have suggested a lower incidence of EAC in nondysplastic BE (NDBE) than previously reported. There is paucity of prospective data showing a survival benefit of screening or surveillance for BE. Furthermore, the ever-increasing emphasis on healthcare cost containment has called for reexamination of the screening and surveillance strategies for BE. There is a need for identification of reliable clinical predictors or molecular biomarkers to risk-stratify patients who might benefit the most from screening or surveillance for BE. Finally, new therapies have emerged for the management of dysplastic BE. In this paper, we highlight the key areas of controversy and uncertainty surrounding BE. The paper discusses, in detail, the current literature about the molecular pathogenesis, biomarkers, histopathological diagnosis, and management strategies for BE.

Clinical implications of molecular changes in pediatric Barrett's esophagus

Barrett's esophagus (BE) is a preneoplastic condition that predisposes to esophageal adenocarcinoma. Although data on the occurrence of BE in children are limited, recent studies have suggested an increase in the pediatric population. BE is thought to be a complex disease in which individual genetic predisposition interacts with environmental stimuli. Early premalignant clones produce biological and genetic heterogeneity, resulting in stepwise changes in differentiation, proliferation, and apoptosis, allowing disease progression under selective pressure. The value of endoscopic surveillance biopsy for dysplasia and carcinoma in patients with BE is controversial. Thus, the recognition of early and objective alternative risk markers, less susceptible of sampling error, will be of relevance in the management of BE patients. The possibility of performing molecular genetics on paraffin-embedded biopsies will expand our understanding of the natural history of BE and may lead to the use of biomarkers to inform treatment strategies.

MUC2 is a highly specific marker of goblet cell metaplasia in the distal esophagus and gastroesophageal junction

Currently, the American College of Gastroenterology requires identification of goblet cells in mucosal biopsies from the esophagus to diagnose Barrett esophagus (BE). Identification of goblet cells in mucosal biopsies is fraught with limitations such as sampling and interpretation error. One previous study by our group suggested that MUC2 expression in esophageal nongoblet columnar cells represents a late biochemical reaction in the conversion of mucinous columnar cells to goblet cells in BE. We conducted this study to evaluate the prevalence, sensitivity, and specificity of MUC2 positivity in nongoblet columnar epithelium for detection of goblet cells in the distal esophagus and gastroesophageal junction (GEJ) region. We also sought to identify associations between MUC2 positivity and clinical and endoscopic risk factors for BE. This analysis utilized mucosal biopsies of the distal esophagus or GEJ from 100 patients who participated in a community clinic-based study of patients with chronic gastroesophageal reflux disease evaluated prospectively in the western part of Washington state. We randomly selected 50 patients who had columnar epithelium with goblet cells, representing the study group and 50 patients without goblet cells, representing the comparison group. Immunohistochemistry for MUC2 was performed on samples in a blinded manner without knowledge of the clinical or endoscopic features of the patients. The presence of staining was noted in both goblet and nongoblet epithelium, both close to and distant from the mucosa with goblet cells, when the latter were present. All study patients showed MUC2 positivity in goblet cells. MUC2 was present in nongoblet columnar epithelium in 78% of study patients with goblet cells, but in only 4% of controls without goblet cells (P<0.0001) (sensitivity, 78%; specificity, 96% for goblet cell metaplasia). MUC2 was significantly more common in nongoblet columnar cells close to, rather than distant from, the mucosa with goblet cells (P<0.00001). Finally, MUC2 was significantly associated with endoscopic evidence of columnar metaplasia in the distal esophagus, and with known risk factors for BE, such as older age, white race, frequent heartburn, and elevated body mass index. We conclude that goblet cells likely develop from a field of MUC2-positive mucinous columnar cells, and as such, MUC2 represents a late event in the development of goblet cells. MUC2 staining in nongoblet columnar cells is a reasonably sensitive and highly specific marker for goblet cells in the distal esophagus and GEJ, and its presence is predictive of endoscopic columnar metaplasia of the esophagus, even in patients without goblet cells.

What the gastroenterologist needs to know about the histology of Barrett's esophagus

PURPOSE OF REVIEW

The purpose of this review is to provide clinicians with an up-to-date summary of the terminology, classification, biological characteristics, and limitations of pathology regarding Barrett's esophagus and associated neoplastic precursor lesions in order to optimize decision making when evaluating patients with this disorder.

RECENT FINDINGS

This review summarizes some of the advancements and controversies regarding the definition and diagnostic criteria for Barrett's esophagus, difficulties that arise when trying to differentiate esophageal versus gastric epithelium in gastroesophageal junction (GEJ) biopsies, the histology and biology of nondysplastic Barrett's esophagus including columnar metaplasia without goblet cells, and the limitations and diagnostic variability in interpretation of conventional and nonconventional types of dysplasia in Barrett's esophagus.

SUMMARY

The definition of Barrett's esophagus is controversial, particularly with regard to the need to identify goblet cells in esophageal biopsies. In most cases, morphologic evaluation of GEJ biopsies cannot help distinguish whether the columnar epithelium comes from the distal esophagus versus the proximal stomach. Metaplastic esophageal columnar epithelium that does not contain goblet cells nevertheless is biologically intestinalized, shows molecular abnormalities, and has been shown to be at risk for progression to cancer, but the magnitude of that risk is unknown. Interobserver agreement on the presence, grade, and type of dysplasia remains moderate at best, particularly in light of the recent recognition of nonconventional types of dysplasia, such as foveolar, serrated, and early crypt dysplasia, which make interpretation difficult. Close cooperation between clinicians and pathologists is essential in order to ensure proper interpretation of biopsy results and to provide optimal surveillance and treatment decisions.

Role of minimally invasive surgery in the modern treatment of Barrett's esophagus

Gastroesophageal reflux disease (GERD) is a highly prevalent disease. Population studies have demonstrated that a significant proportion of individuals weekly experience GERD symptoms. Barrett's esophagus (BE), defined by the presence of intestinal metaplasia (columnar epithelium with goblet cells), is considered a consequence of chronic reflux. This review defines the role of surgery in the modern treatment of BE, taking into consideration the pathophysiology of the disease and the new endoscopic procedures available at present.

Diagnostic challenges in the pathologic evaluation of Barrett esophagus

CONTEXT

Barrett esophagus represents an unstable epithelium resulting from chronic gastroesophageal reflux disease. Patients with Barrett esophagus routinely undergo endoscopic examination to detect dysplasia and early carcinoma. Although appropriate classification of Barrett esophagus and neoplasia is usually straightforward, persistent esophageal inflammation may induce epithelial changes that mimic, or mask, dysplasia. Recent data also indicate that specific molecular changes occur in nondysplastic Barrett mucosa and herald the development of dysplasia and/or carcinoma.

OBJECTIVE

To describe problematic aspects of biopsy interpretation in tissue samples of the gastroesophageal junction and distal esophagus, including the diagnostic criteria for Barrett esophagus, the importance of the gastric cardia, and pitfalls to the diagnosis of dysplasia. Ancillary studies that have recently emerged as potential adjuncts to the evaluation of patients with Barrett esophagus will be briefly discussed.

DATA SOURCES

A comprehensive review of the relevant literature indexed in PubMed (National Library of Medicine) was performed.

CONCLUSIONS

Barrett esophagus is currently defined as the presence of intestinal metaplasia in samples obtained from an endoscopically evident abnormality in the distal esophagus. Diagnosis and grading of dysplasia in mucosal biopsies remain the most reliable method to assess risk for neoplastic progression, but its classification may be hindered by superimposed inflammatory changes and suffers from considerable interobserver variability. Therefore, immunohistochemical studies and molecular assessment for TP53, CDKN2A , and DNA content abnormalities have emerged as potential adjuncts to the detection of dysplasia.

The histologic squamo-oxyntic gap: an accurate and reproducible diagnostic marker of gastroesophageal reflux disease

The present definition of gastroesophageal reflux disease (GERD) is based on clinical criteria that are difficult to reproduce accurately. This study provides a method to develop a histologic definition of GERD based on biopsies obtained from the affected esophagus. Pathology reports from 1655 patients who had upper gastrointestinal endoscopy and biopsy according to a systematic protocol were reviewed. Biopsies were obtained from the esophagus, around the gastroesophageal junction and the stomach: proximal, body, and antrum. Patients who had oxyntocardiac±cardiac±intestinal epithelia between the squamous epithelium proximally and the proximal limit of gastric oxyntic mucosa distally were defined as having a squamo-oxyntic gap. The length of the squamo-oxyntic gap varied from less than 1 cm in 1399 (84.5%) patients to greater than 5 cm in 80 (4.8%) of the patients. Only oxyntocardiac epithelium was seen in 190 (11.5%) of the patients, oxyntocardiac and cardiac epithelia in 898 (54.3%), and intestinal metaplasia in addition to the other 2 epithelial types in 567 (34.2%). The prevalence of intestinal metaplasia was directly proportional to length of the squamo-oxyntic gap, being 24.3% (340/1399) when the length was <1 cm, and 83.5% (147/176) with length 1 to 5 cm. All patients with a length more than 5 cm had intestinal metaplasia. The distribution of the 3 epithelia was constant irrespective of the length of the squamocolumnar gap; intestinal metaplasia, when present, was seen maximally in the proximal region of the gap, cardiac epithelium intermediate and oxyntocardiac epithelium in the most distal segment of the gap. The squamo-oxyntic gap started in a dilated region distal to the end of the tubular esophagus and distal to the proximal limit of the rugal folds and extended into the tubular esophagus. Distal gastric biopsies showed no evidence of significant inflammation, intestinal metaplasia or Helicobacter pylori infection in 1543 (93.2%) of the patients, indicating that the squamo-oxyntic gap was largely independent of gastric pathology. We provide evidence that the squamo-oxyntic gap is equivalent to the columnar-lined esophagus. Its presence is a specific and sensitive indicator of reflux and can be used as a cellular criterion to define GERD. The length of the squamo-oxyntic gap provides an accurate assessment of the severity of chronic GERD. The distal limit of the squamo-oxyntic gap, which is the junction between oxyntocardiac and gastric oxyntic epithelium is the true gastroesophageal junction. The presence of intestinal metaplasia within the squamo-oxyntic gap is the most accurate risk indicator for esophageal adenocarcinoma and defines Barrett esophagus.

Pathophysiology and treatment of Barrett’s esophagus

Gastroesophageal reflux disease (GERD) affects an estimated 20% of the population in the United States. About 10%-15% of patients with GERD develop Barrett’s esophagus, which can progress to adenocarcinoma, currently the most prevalent type of esophageal cancer. The esophagus is normally lined by squamous mucosa, therefore, it is clear that for adenocarcinoma to develop, there must be a sequence of events that result in transformation of the normal squamous mucosa into columnar epithelium. This sequence begins with gastroesophageal reflux, and with continued injury metaplastic columnar epithelium develops. This article reviews the pathophysiology of Barrett’s esophagus and implications for its treatment. The effect of medical and surgical therapy of Barrett’s esophagus is compared.

Treatment for Barrett's oesophagus

BACKGROUND

Treatments for Barrett's oesophagus, the precursor lesion of adenocarcinoma, are available but whether these therapies effectively prevent the development of adenocarcinoma, and in some cases eradicate the Barrett's oesophagus segment, remains unclear.

OBJECTIVES

To summarise, quantify and compare the efficacy of pharmacological, surgical and endoscopic treatments for the eradication of dysplastic and non-dysplastic Barrett's oesophagus and prevention of these states from progression to adenocarcinoma.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2004, issue 4), MEDLINE (1966 to June 2008) and EMBASE (1980 to June 2008).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing medical, endoscopic or non-resectional surgical treatments for Barrett's oesophagus. The primary outcome measures were complete eradication of Barrett's and dysplasia at 12 months, and reduction in the number of patients progressing to cancer at five years or latest time point.

DATA COLLECTION AND ANALYSIS

Three authors independently extracted data and assessed the quality of the trials included in the analysis.

MAIN RESULTS

Sixteen studies, including 1074 patients, were included. The mean number of participants in the studies was small (n = 49; range 8 to 208). Most studies did not report on the primary outcomes. Medical and surgical interventions to reduce symptoms and sequelae of gastro-oesophageal reflux disease (GORD) did not induce significant eradication of Barrett's oesophagus or dysplasia. Endoscopic therapies (photodynamic therapy (PDT with aminolevulinic acid or porfimer sodium), argon plasma coagulation (APC) and radiofrequency ablation (RFA)) all induced regression of Barrett's oesophagus and dysplasia. The data for photodynamic therapy were heterogeneous with a mean eradication rate of 51% for Barrett's oesophagus and between 56% and 100% for dysplasia, depending on the treatment regimens. The variation in photodynamic therapy eradication rates for dysplasia was dependent on the drug, source and dose of light. Radiofrequency ablation resulted in eradication rates of 82% and 94% for Barrett's oesophagus and dysplasia respectively, compared to a sham treatment. Endoscopic treatments were generally well tolerated, however all were associated with some buried glands, particularly following argon plasma coagulation and photodynamic therapy, as well as photosensitivity and strictures induced by porfimer sodium based photodynamic therapy in particular.

AUTHORS' CONCLUSIONS

Despite their failure to eradicate Barrett's oesophagus, the role of medical and surgical interventions to reduce the troubling symptoms and sequelae of GORD is not questioned. Whether therapies for GORD reduce the cancer risk is not yet known. Ablative therapies have an increasing role in the management of dysplasia within Barrett's and current data would favour the use of radiofrequency ablation compared with photodynamic therapy. Radiofrequency ablation has been shown to yield significantly fewer complications than photodynamic therapy and is very efficacious at eradicating both dysplasia and Barrett's itself. However, long-term follow-up data are still needed before radiofrequency ablation can be used in routine clinical care without the need for very careful post-treatment surveillance. More clinical trial data and in particular randomised controlled trials are required to assess whether or not the cancer risk is reduced in routine clinical practice.

Definition of Barrett's esophagus: time for a rethink--is intestinal metaplasia dead?

The definition of Barrett's esophagus (BE) varies worldwide, particularly with regard to the need to identify goblet cells in esophageal biopsies in order to diagnose this condition. Problems related to the need to identify goblet cells to diagnose BE include the facts that goblet cells are uncommon in pediatric patients with BE, a small percentage of adults with columnar metaplasia of the esophagus do not contain goblet cells, the chances of detecting goblet cells are proportional to the length of columnar metaplasia, sampling error is common, and interpretation and differentiation of goblet cells vs. pseudogoblet cells may be difficult in some circumstances. In addition, goblet cells have been shown to wax and wane over the natural history of BE. Recent studies suggest that the background nongoblet epithelium in BE is biologically intestinalized, and shows a variety of molecular abnormalities similar to the goblet cell-containing epithelium. In addition, several retrospective and outcome studies suggest a well-defined risk of neoplasia in patients with esophageal columnar metaplasia, but without goblet cells. There are important clinical and economic implications to these findings and also with regard to the definition of BE. This review provides evidence to suggest that a diagnosis of BE should not require demonstration of goblet cells in mucosal biopsies, and offers considerable data to support the notion that a nongoblet epithelium is also at risk of malignancy. Guidelines for the diagnosis of BE need to consider revisions that take into account new data regarding nongoblet cell epithelium in BE, and the difficulties in recognizing columnar metaplasia that measures less than 1 cm in length.

Advances in the diagnosis of Barrett's esophagus

Barrett's esophagus is a metaplastic change in esophageal lining, characterized by the replacement of normal squamous epithelium with columnar epithelium. Barrett's esophagus is associated with a high risk of esophageal adenocarcinoma. As the incidence of esophageal adenocarcinoma has risen dramatically in developed countries, the research on Barrett's esophagus is attracting increasing attention. In this article, we will review the recent advances in the diagnosis of Barrett's esophagus.

Screening and surveillance of Barrett's esophagus

Esophageal adenocarcinoma (EAC) is the most rapidly increasing cancer in the Western world and Barrett's esophagus (BE) is the only known precursor lesion for this lethal cancer. Long-term survival may be improved if EAC is diagnosed early, providing an opportunity for early intervention. Screening for BE in patients with gastroesophageal reflux disease is not routinely recommended; however, if diagnosed, enrollment into a surveillance program may be beneficial. Surveillance of all patients with known BE is probably not cost-effective and factors predictive of BE progression to dysplasia/EAC are poorly understood. Screening and surveillance examinations are also faced with challenges in the endoscopic detection of intestinal metaplasia and dysplasia. Future application of molecular biomarkers may help identify the patients with BE most likely to progress, and the use of novel imaging methods may improve outcomes of BE screening and surveillance.

Barrett esophagus: histology and pathology for the clinician

The incidence of adenocarcinoma of the esophagus and gastroesophageal junction has increased dramatically over the past 30 years. The major precursor to this type of adenocarcinoma is Barrett esophagus, which is defined as the conversion of normal squamous epithelium into metaplastic columnar epithelium. Abundant evidence suggests that adenocarcinoma in the setting of Barrett esophagus develops via a progressive sequence of histological and molecular events. Consequently, patients with Barrett esophagus routinely undergo endoscopic surveillance for early detection of neoplasia. Histological evaluation of mucosal biopsy samples from the esophagus and gastroesophageal junction for identification of goblet cells and evaluation of the presence, grade and extent of dysplasia is the mainstay of risk assessment for these patients. This Review provides physicians with a summary of the pertinent, clinically relevant histological features of Barrett esophagus and its neoplastic complications. The histology of Barrett esophagus and the gastroesophageal junction is summarized, and an overview of information necessary to interpret pathology reports from patients either with or without endoscopic evidence of Barrett esophagus is provided to appropriately guide management of patients. Close interaction between the clinician and the pathologist is essential for proper interpretation of biopsy results and to provide optimal surveillance or treatment strategies.

Pediatric columnar lined esophagus vs Barrett's esophagus: is it the time for a consensus definition

We describe the clinical, endoscopic, and histological features of all cases of Barrett's esophagus (BE) diagnosed at our institution between 2000 and 2007 following the criteria of the British Society of Gastroenterology. This society defines BE as a segment of columnar metaplasia (CLO) (whether intestinalized or not) of any length, visible endoscopically above the gastroesophageal junction and confirmed histologically. The diagnosis was challenged after immunostaining for Cdx2 (marker of intestinal differentiation). Information was collected with respect to age, symptoms, treatment, and endoscopic and histological features. Twelve children (10 males and 2 females) with a median age of 11.7 (2 to 17) years had been diagnosed with CLO-BE. Histology confirmed BE in 31 of 38 endoscopies. The initial diagnosis was reviewed according to Cdx2 results in 10 of 12 patients: Cdx2 strongly expressed in 4 cases with intestinal metaplasia (the diagnosis of BE was maintained); was negative in 4 other patients with "CLO" mucosa (reviewed diagnosis was that of expansion of the gastric cardia into the distal esophagus); and 2 patients had occasional Cdx2-positive cells showing cardia-type mucosa with goblet cells (early BE?). The estimated prevalence of CLO-BE in the pediatric population of South Yorkshire (United Kingdom) is 0.0024%, 0.8% in children referred for endoscopy and 5.5% in the children with reflux esophagitis. Characterization of the BE and confirmation of intestinal differentiation may have prognostic implications that can impact the surveillance program. Our results showed that intestinal differentiation as demonstrated with Cdx2 was only seen if goblet cells were present. A consensus definition and further studies to understand the molecular mechanisms involved in the development of BE at this age are needed.

Optimal approach to obtaining mucosal biopsies for assessment of inflammatory disorders of the gastrointestinal tract

Endoscopic evaluation and mucosal biopsy analysis have assumed important roles in the clinical management of patients with symptoms related to the gastrointestinal tract. Several common inflammatory diseases, including eosinophilic esophagitis, Barrett's esophagus, Helicobacter pylori infection, celiac disease, lymphocytic colitis, collagenous colitis, and inflammatory bowel disease, may display a patchy or discontinuous distribution and, thus, multiple mucosal samples may be required to obtain diagnostic tissue in some cases. Not surprisingly, clinicians and pathologists are increasingly challenged to determine the optimum number of procedures and tissue samples necessary to detect, or exclude, the presence of inflammatory disorders of the gastrointestinal tract. Unfortunately, clinical practice varies widely with respect to tissue sample procurement in the evaluation of these disorders, particularly when the endoscopic appearance of the gastrointestinal mucosa is normal or shows only minimal changes. Guidelines concerning the appropriate number of tissue samples are well established for some diseases, such as Barrett's esophagus and chronic gastritis, but are not clear in other instances. The purpose of this review is to discuss the available literature pertaining to appropriate endoscopic sampling in the assessment of medical diseases of the gastrointestinal tract, and to develop recommendations regarding the clinical evaluation of common gastrointestinal disorders.

The application of Prague C and M criteria in the diagnosis of Barrett's esophagus in an ethnic Chinese population

OBJECTIVES

To investigate the prevalence of endoscopically suspected esophageal metaplasia (ESEM) in an ethnic Chinese population by endoscopic and pathologic evaluation and to assess the utility of Prague C and M criteria.

METHODS

Consecutive patients who received esophagogastroduodenoscopy either as a part of therapy for various upper abdominal symptoms or as an annual health check-up were evaluated for the existence of ESEM and Barrett's esophagus (BE). Biopsy with standardized random four pieces every 2 cm from the four quarters of esophagus with ESEM lesion was performed. BE was defined by histological verification of specialized intestinal metaplasia and gastric metaplasia and was categorized according to the Prague C and M criteria.

RESULTS

A total of 5,179 subjects were screened from Jan. 2007 to Dec. 2007. This study enrolled 4,797, including 3,386 for referral endoscopy and 1,411 for screening endoscopy. Prevalence of BE among the referral endoscopy, screening endoscopy, and overall was 1.06%, 0.35%, and 0.85%, respectively. A total of 41 subjects with BE were detected among 93 ESEM subjects. Short segment BE (75.6%, n=31) was more prevalent than long segment BE (24.4%, n=10). The proportions of BE from subjects with ESEM by Prague C and M criteria were C< or =1M1 38.9% (19/50), C< or =1M2 40% (12/30), and CxM> or =3 76.9% (10/13).

CONCLUSIONS

On the basis of the standardized protocol with random four-quadrate endoscopic biopsy, we have demonstrated the utility of Prague C and M criteria to characterize the BE in an ethnic Chinese population.

Transnasal Esophagoscopy: White-Light versus Narrowband Imaging

Objectives:

Transnasal esophagoscopy (TNE) is rapidly becoming integrated into otolaryngological practice. A recent report has shown an incongruence between an endoscopic diagnosis of Barrett's esophagus and biopsy-proven Barrett's esophagus in patients with laryngopharyngeal reflux (LPR). The goal of this study was to determine whether performing TNE with narrowband imaging (NBI) improves on the diagnostic yield in the otolaryngologist's hands. Narrowband imaging involves the use of filtered light to enhance the mucosal microvasculature pattern and has been shown to be highly sensitive to detecting Barrett's esophagus under conventional esophagoscopy.

Methods:

A retrospective chart review of 111 patients with LPR who underwent TNE by the same otolaryngologist was carried out. Pentax EE-1580K (white light only) and Olympus GIF-N180 (with NBI) endoscopes were used in 58 and 53 patients, respectively. Microcup biopsy of the squamocolumnar junction was obtained when Barrett's esophagus was suspected.

Results:

Biopsy-proven Barrett's esophagus was found in 13.5% of the patients. According to white light only and NBI, 7 of 58 (12.1%) and 8 of 53 (15.1%), respectively, had biopsy-proven Barrett's esophagus. Three patients had dysplasia on biopsy (2.7%), and all of these cases were detected under NBI (5.7%).

Conclusions:

Narrowband imaging may be a useful adjunct in increasing the diagnostic sensitivity of TNE in the hands of the otolaryngologist.