Can extent of high grade dysplasia in Barrett's oesophagus predict the presence of adenocarcinoma at oesophagectomy?

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.

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.

Depth-resolved imaging of colon tumor using optical coherence tomography and fluorescence laminar optical tomography

Early detection of neoplastic changes remains a critical challenge in clinical cancer diagnosis and treatment. Many cancers arise from epithelial layers such as those of the gastrointestinal (GI) tract. Current standard endoscopic technology is difficult to detect the subsurface lesions. In this research, we investigated the feasibility of a novel multi-modal optical imaging approach including high-resolution optical coherence tomography (OCT) and high-sensitivity fluorescence laminar optical tomography (FLOT) for structural and molecular imaging. The C57BL/6J-Apc^Min/J mice were imaged using OCT and FLOT, and the correlated histopathological diagnosis was obtained. Quantitative structural (scattering coefficient) and molecular (relative enzyme activity) parameters were obtained from OCT and FLOT images for multi-parametric analysis. This multi-modal imaging method has demonstrated the feasibility for more accurate diagnosis with 88.23% (82.35%) for sensitivity (specificity) compared to either modality alone. This study suggested that combining OCT and FLOT is promising for subsurface cancer detection, diagnosis, and characterization.

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.

Dysplasia in Barrett's oesophagus: p53 immunostaining is more reproducible than haematoxylin and eosin diagnosis and improves overall reliability, while grading is poorly reproducible

AIMS

p53 immunostaining in Barrett's oesophagus (BO) has been shown to be predictive of progression, but data regarding its generalizability to routine practice are lacking. This study compared the reliability of p53 and dysplasia interpretation and grading.

METHODS AND RESULTS

Seventy-two cases encompassing the full spectrum of BO were circulated to 10 pathologists from four institutions after a brief training session in p53 interpretation. Each pathologist classified cases on haematoxylin and eosin (H&E) alone using the Vienna classification and assessed the p53 staining using a qualitative system. Agreement was assessed using kappa statistics. For the four-tier Vienna system, the average unweighted kappa was 0.30. Weighted kappa values varied from 0.27 to 0.69 with an average of 0.47. When grouped into definite dysplasia versus no definite dysplasia the average kappa was 0.55, but the kappa for low-grade dysplasia (LGD) versus high-grade dysplasia (HGD) was only 0.31. For p53, using the three recognized patterns, the unweighted kappa was 0.6 (confidence interval 0.58-0.63). When cases were evaluated with both H&E and p53 the average kappa was 0.61 for definite dysplasia versus the rest.

CONCLUSIONS

p53 immunohistochemistry interpretation is more reliable than dysplasia diagnosis, even with limited training. As it is predictive of prognosis and improves diagnostic reproducibility, it is suitable for routine use by pathologists as an adjunct to dysplasia diagnosis. The distinction of LGD versus HGD was poor. This study supports simplifying dysplasia diagnosis into 'present', 'indefinite' or 'absent', and the use of p53 as an ancillary marker in difficult cases. This should help to prevent overdiagnosis of dysplasia and inappropriate treatment.

TissueCypher(™): A systems biology approach to anatomic pathology

Background:

Current histologic methods for diagnosis are limited by intra- and inter-observer variability. Immunohistochemistry (IHC) methods are frequently used to assess biomarkers to aid diagnoses, however, IHC staining is variable and nonlinear and the manual interpretation is subjective. Furthermore, the biomarkers assessed clinically are typically biomarkers of epithelial cell processes. Tumors and premalignant tissues are not composed only of epithelial cells but are interacting systems of multiple cell types, including various stromal cell types that are involved in cancer development. The complex network of the tissue system highlights the need for a systems biology approach to anatomic pathology, in which quantification of system processes is combined with informatics tools to produce actionable scores to aid clinical decision-making.

Aims:

Here, we describe a quantitative, multiplexed biomarker imaging approach termed TissueCypher™ that applies systems biology to anatomic pathology. Applications of TissueCypher™ in understanding the tissue system of Barrett's esophagus (BE) and the potential use as an adjunctive tool in the diagnosis of BE are described.

Patients and Methods:

The TissueCypher™ Image Analysis Platform was used to assess 14 epithelial and stromal biomarkers with known diagnostic significance in BE in a set of BE biopsies with nondysplastic BE with reactive atypia (RA, n = 22) and Barrett's with high-grade dysplasia (HGD, n = 17). Biomarker and morphology features were extracted and evaluated in the confirmed BE HGD cases versus the nondysplastic BE cases with RA.

Results:

Multiple image analysis features derived from epithelial and stromal biomarkers, including immune biomarkers and morphology, showed significant differences between HGD and RA.

Conclusions:

The assessment of epithelial cell abnormalities combined with an assessment of cellular changes in the lamina propria may serve as an adjunct to conventional pathology in the assessment of BE.

Epidemiology of Barrett's Esophagus and Esophageal Adenocarcinoma

Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC), a disease with increasing burden in the Western world, especially in white men. Risk factors for BE include obesity, tobacco smoking, and gastroesophageal reflux disease (GERD). EAC is the most common form of esophageal cancer in the United States. Risk factors include GERD, tobacco smoking, and obesity, whereas nonsteroidal antiinflammatory drugs and statins may be protective. Factors predicting progression from nondysplastic BE to EAC include dysplastic changes on esophageal histology and length of the involved BE segment. Biomarkers have shown promise, but none are approved for clinical use.

Progression of Barrett oesophagus: role of endoscopic and histological predictors

Barrett oesophagus is an important precursor lesion for the development of oesophageal adenocarcinoma (OAC). Upper gastrointestinal endoscopy is the modality most widely used to visualize and biopsy the oesophagus to establish a diagnosis. Additional clues are available at the time of endoscopy that can identify high-risk features known to increase the risk of progression to OAC, such as the length of the Barrett oesophagus segment, length of hiatal hernia and the presence of nodularity or visible endoscopic lesions in this segment. Until molecular biomarkers are identified and validated as adjunctive tools for risk stratification, knowledge of endoscopic features could complement dysplasia grading for risk stratification of patients with Barrett oesophagus and identify subgroups at risk of progression to OAC. This approach would, in turn, facilitate more rational tailoring of endoscopic surveillance. This Review summarizes the current role of endoscopic and histological factors involved in neoplastic progression of Barrett oesophagus to OAC, and provides an overview of the risk-prediction models that have utilized endoscopic and histological factors for risk stratification in patients with Barrett oesophagus.

Minimally invasive esophagectomy for dysplastic Barrett's esophagus

A substantial portion of patients diagnosed preoperatively with high grade dysplasia (HGD) alone will have occult esophageal adenocarcinoma on analysis of the surgical specimen. Therefore, because of an increased risk of disease progression and malignancy, patients with HGD should be referred for esophagectomy promptly when endoscopic therapy has failed. The required extent of lymphadenectomy in this cohort of patients is unknown because of the variable incidence of submucosal cancer observed. Improvements in perioperative care, adoption of a minimally invasive surgical approach, and centralization of esophageal cancer services have substantially reduced the rates of mortality and morbidity associated with esophagectomy in recent years. Minimally invasive esophagectomy should be considered the treatment of choice in patients with dysplastic Barrett's esophagus that is refractory to endoscopic therapy or those at high risk of invasive cancer.

Surveillance for low-grade dysplastic Barrett's oesophagus: one size fits all?

This paper reviews the role of low-grade dysplasia (LGD) as a marker of progression in Barrett's oesophagus (BO). Albeit with its limits due to the difficulty of its diagnosis and the low agreement among pathologists, LGD remains the most relevant single prognostic factor of progression, and, when the diagnosis is confirmed by two or three pathologists, the chances of progression to high-grade dysplasia or invasive adenocarcinoma are as high as 40%. On the other hand, BO patients who remain dysplasia free at several follow-up examinations seem to have a very low likelihood of progression. The diagnosis of LGD should be confirmed by two pathologists, and surveillance programs should be tailored depending on the presence or persistent absence of LGD. Ablative therapy should be also considered for cases where LGD persists in a series of follow-ups.

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.

Radiofrequency ablation in the management of Barrett's esophagus: present role and future perspective

Esophageal adenocarcinoma is the most rapidly increasing gastrointestinal cancer. Barrett's esophagus has been identified as a precancerous condition and major risk factor for esophageal cancer. Radiofrequency ablation has been shown to be a highly efficient in promoting remission of intestinal metaplasia. This technology has seen widespread clinical use since 2005. Radiofrequency ablation is common with all other ablative techniques; the concern that sound oncological principles are not being adhered to, that is, appropriate pathological staging, followed by appropriate definitive therapy. Endoscopic mucosal excision techniques are technically demanding; however, they are more attractive from an oncological perspective. Future research endeavors focusing on facilitation of large population screening, the identification of high risk phenotypes, endoscopic mucosal resection techniques will combat the esophageal adenocarcinoma epidemic.

Consensus statements for management of Barrett's dysplasia and early-stage esophageal adenocarcinoma, based on a Delphi process

BACKGROUND & AIMS

Esophageal adenocarcinoma (EA) is increasingly common among patients with Barrett's esophagus (BE). We aimed to provide consensus recommendations based on the medical literature that clinicians could use to manage patients with BE and low-grade dysplasia, high-grade dysplasia (HGD), or early-stage EA.

METHODS

We performed an international, multidisciplinary, systematic, evidence-based review of different management strategies for patients with BE and dysplasia or early-stage EA. We used a Delphi process to develop consensus statements. The results of literature searches were screened using a unique, interactive, Web-based data-sifting platform; we used 11,904 papers to inform the choice of statements selected. An a priori threshold of 80% agreement was used to establish consensus for each statement.

RESULTS

Eighty-one of the 91 statements achieved consensus despite generally low quality of evidence, including 8 clinical statements: (1) specimens from endoscopic resection are better than biopsies for staging lesions, (2) it is important to carefully map the size of the dysplastic areas, (3) patients that receive ablative or surgical therapy require endoscopic follow-up, (4) high-resolution endoscopy is necessary for accurate diagnosis, (5) endoscopic therapy for HGD is preferred to surveillance, (6) endoscopic therapy for HGD is preferred to surgery, (7) the combination of endoscopic resection and radiofrequency ablation is the most effective therapy, and (8) after endoscopic removal of lesions from patients with HGD, all areas of BE should be ablated.

CONCLUSIONS

We developed a data-sifting platform and used the Delphi process to create evidence-based consensus statements for the management of patients with BE and early-stage EA. This approach identified important clinical features of the diseases and areas for future studies.

The risk of lymph-node metastases in patients with high-grade dysplasia or intramucosal carcinoma in Barrett's esophagus: a systematic review

OBJECTIVES

Endoscopic eradication therapy is used to treat mucosal neoplasms in Barrett's esophagus, but cannot cure cancers that have metastasized to lymph nodes. The risk of such metastases has been proposed as a reason to consider esophagectomy rather than endoscopic therapy for esophageal mucosal neoplasia. The objective of our study was to determine the frequency of lymph-node metastases in patients with high-grade dysplasia (HGD) and intramucosal carcinoma in Barrett's esophagus.

METHODS

We performed a systematic review using the PRISMA guidelines to identify studies that included patients who had esophagectomy for HGD or intramucosal carcinoma in Barrett's esophagus, and that reported final pathology results after examination of esophagectomy specimens.

RESULTS

We identified 70 relevant reports that included 1,874 patients who had esophagectomy performed for HGD or intramucosal carcinoma in Barrett's esophagus. Lymph-node metastases were found in 26 patients (1.39 % , 95 % CI 0.86 – 1.92). No metastases were found in the 524 patients who had a final pathology diagnosis of HGD, whereas 26 (1.93 % , 95 % CI 1.19 – 2.66 %) of the 1,350 patients with a final pathology diagnosis of intramucosal carcinoma had positive lymph nodes.

CONCLUSIONS

The risk of unexpected lymph-node metastases for patients with mucosal neoplasms in Barrett's esophagus is in the range of 1 – 2 %. Esophagectomy has a mortality rate that often exceeds 2 %, with substantial morbidity and no guarantee of curing metastatic disease. Therefore, the risk of lymph node metastases alone does not warrant the choice of esophagectomy over endoscopic therapy for HGD and intramucosal carcinoma in Barrett's esophagus.

[Surgical management of early cancer in Barrett's esophagus]

The indication of surgical resection for early cancer in Barrett's esophagus is based on the risk of lymph node extension, which is conditioned by the depth of the lesions. Even if the high resolution endosonography is more sensitive than conventional endosonography for differentiating mucosal from submucosal lesions, it may be lacking for intermediate lesions (m3 and sm1). Macroscopic criteria are useful for identifying high-risk lesions. In contentious cases, endoscopic resection may be considered as a biopsy to determine the further treatment. The endoscopic resection is indicated for mucosal lesions in selected patients. Surgery remains the standard treatment for early cancer in Barrett's esophagus. The transhiatal resection is indicated for high-risk T1a mucosal lesions. The transthoracic resection is indicated for submucosal lesions.

Barrett's esophagus surveillance: When, how often, does it work?

Barrett's esophagus is a well-known risk factor for the development of esophageal adenocarcinoma. Current practice guidelines recommend endoscopic surveillance of patients with Barrett's esophagus in an attempt to detect cancer at an early and potentially curable stage. This review addresses the rationale behind surveillance and criteria for inclusion of patients in surveillance programs as well as the appropriate technique and intervals that should be used. This work addresses other key topics in Barrett's esophagus surveillance, including the efficacy of surveillance programs, physician compliance with surveillance guidelines, cost-effectiveness of surveillance programs, and areas for future research.

A UK-based cost-utility analysis of radiofrequency ablation or oesophagectomy for the management of high-grade dysplasia in Barrett's oesophagus

BACKGROUND

In the UK, oesophagectomy is the current recommendation for patients with persistent high-grade dysplasia in Barrett's oesophagus. Radiofrequency ablation is an alternative new technology with promising early trial results.

AIM

To undertake a cost-utility analysis comparing these two strategies.

METHODS

We constructed a Markov model to simulate the natural history of a cohort of patients with high-grade dysplasia in Barrett's oesophagus undergoing one of two treatment options: (i) oesophagectomy or (ii) radiofrequency ablation followed by endoscopic surveillance with oesophagectomy for high-grade dysplasia recurrence or persistence.

RESULTS

In the base case analysis, radiofrequency ablation dominated as it generated 0.4 extra quality of life years at a cost saving of £1902. For oesophagectomy to be the most cost-effective option, it required a radiofrequency ablation treatment failure rate (high-grade dysplasia persistence or progression to cancer) of >44%, or an annual risk of high-grade dysplasia recurrence or progression to cancer in the ablated oesophagus of >15% per annum. There was an 85% probability that radiofrequency ablation remained cost-effective at the NICE willingness to pay threshold range of £20 000-30 000.

CONCLUSION

Radiofrequency ablation is likely to be a cost-effective option for high-grade dysplasia in Barrett's oesophagus in the UK.

Predictors of progression in Barrett's esophagus: current knowledge and future directions

Barrett's esophagus (BE) is the strongest risk factor for esophageal adenocarcinoma (EAC), a malignancy with persistently poor long-term outcomes. EAC is thought to develop through progression of metaplasia to dysplasia to invasive carcinoma. Identification of factors predicting progression to EAC would help in focusing surveillance, chemoprevention, or ablation for those deemed to be at highest risk of progression. We performed a comprehensive review of the literature and summarized current evidence on risk factors for progression in subjects with known BE. Clinical and demographic factors (age, male gender, length of BE segment) are associated with modestly increased odds of progression to EAC in some studies. Biomarkers such as aneuploidy and p53 loss of heterozygosity have been associated with increased risk of progression to high-grade dysplasia and/or EAC in single-center prospective cohort studies. Promising newer techniques and markers have been recently reported with the potential to help risk stratify BE subjects. Development of a comprehensive BE risk progression score comprised of both clinical and biomarker variables should be the ultimate goal and can be achieved by multicenter prospective collaborative efforts. Although it would be challenging, creation of such a score has the potential to improve outcomes and make the management of patients with BE more cost-effective.

Predicting Neoplastic Progression in Barrett's Esophagus

Patients with Barrett's esophagus have a significantly increased risk of esophageal adenocarcinoma, 40-125 times higher than the general population. Since only a small fraction of Barrett's esophagus patients will actually progress to esophageal adenocarcinoma, there is a need to develop markers that may accurately predict which patients with Barrett's esophagus are likely to have aggressive disease and progress to cancer versus patients who will remain histologically stable and have a benign course. This would allow for better risk stratification of patients with Barrett's esophagus in order to target aggressive surveillance and intervention towards only those patients at highest risk for neoplastic progression. Predictive biomarkers may thus have significant clinical utility in the management of Barrett's esophagus patients. The detection of dysplasia in esophageal biopsies is currently the only standard method used in clinical practice as a marker for increased risk of cancer. However, dysplasia has not been a accurate or reliable marker for predicting malignant progression and suffers from poor interobserver agreement among pathologists and sampling error. A multitude of potential biomarkers have been studied over the years. It is likely that the best model for predicting progression to esophageal adenocarcinoma in Barrett's esophagus patients will ultimately involve a combination of biomarkers, dysplasia grade and other pathological characteristics, as well as clinical and demographic attributes. In this review, we will discuss the most promising biomarkers that have been studied thus far.

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.

Pathology and pathobiology of the oesophageal carcinoma

Carcinoma of the oesophagus including carcinoma of gastro-oesophageal junction are rapidly increasing in incidence. During recent years there have been changes in the knowledge surrounding biology of the disease progression. Identification of dysplasia in mucosal biopsies is the most reliable pathologic indicator of an increased risk of development of squamous cell carcinoma and passes through the sequence of chronic esophagitis, low-grade and high-grade dysplasia and invasive carcinoma. Although Barrett's esophagus is a precursor to esophageal adenocarcinoma and have a well described sequence of carcinogenesis: the Barrett's metaplasia-dysplasia-adenocarcinoma sequence, not all patients with this disorder require intensive surveillance. The natural history of dysplasia is poorly understood, particularly in low-risk regions, and prospective follow-up studies are needed. Adjunctive methods to improve reproducibility, such as immunostaining for alpha-methylacyl-coenzyme A racemase (AMACR), show promise, but require confirmation in larger studies. In addition, several controversial methods such as detection of p16, p53, and DNA content abnormalities may help identify patients at particularly high risk for progression to cancer, but these techniques are not yet widely available for routine clinical application. More studies are needed to define other early nonmorphologic biomarkers for risk of squamous cell carcinoma. Recent evidence regarding the importance of several histopathologically derived prognostic factors, such as circumferential resection margin status and lymph node metastases are evaluated, including lymph node micrometastases and the sentinel node concept. With the rising use of multimodal treatments for oesophageal cancer it is important that the response of the tumour to this therapy can be carefully documented by histopathology.

Histology of metaplasia and dysplasia in Barrett's esophagus

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

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.

A histologically defined subset of high-grade dysplasia in Barrett mucosa is predictive of associated carcinoma

To ascertain the prevalence of carcinoma in esophagi resected for high-grade dysplasia (HGD) using current criteria and to evaluate histologic features that may predict concurrent carcinoma, we studied specimens from 127 esophagectomies performed for HGD, or HGD "suspicious" for carcinoma (HGD/S) in Barrett mucosa. Corresponding biopsy specimens in 69 cases were reviewed and reclassified. Based on original diagnoses, carcinoma was present in 15 (17%) of 89 HGD and 28 (74%) of 38 HGD/S cases. By reclassification, only 1 (5%) of 21 cases with HGD had carcinoma in the resection specimen. Of 25 cases reclassified as HGD/S, 18 (72%) had carcinoma in the resection specimen, as did 17 (74%) of 23 reclassified as adenocarcinoma. With 1 additional select histologic feature, the risk of carcinoma was 39%; with 2 or more features, the risk increased to 83% to 88%. Based on current criteria, no more than 5% of esophagectomies performed for a biopsy diagnosis of Barrett HGD harbor carcinoma. When HGD/S is diagnosed based on certain additional features, carcinoma is found in nearly 40% of cases with 1 feature and more than 80% with 2 or more features. Our findings highlight the evolution of diagnostic criteria for Barrett dysplasia.

The Society of Thoracic Surgeons practice guideline series: guidelines for the management of Barrett's esophagus with high-grade dysplasia

The management of Barrett's esophagus with high-grade dysplasia is controversial. The standard of care has traditionally been esophagectomy. However, a number of treatment options aimed at esophageal preservation are increasingly being utilized by many centers. These esophageal-sparing approaches include endoscopic surveillance, mucosal ablation, and endoscopic mucosal resection. In this guideline we review the best evidence supporting these commonly used strategies for high-grade dysplasia to better define management and guide future investigation.

The Seattle protocol does not more reliably predict the detection of cancer at the time of esophagectomy than a less intensive surveillance protocol

BACKGROUND & AIMS

The optimal management of high-grade dysplasia in Barrett's esophagus remains controversial. A biopsy protocol consisting of 4 quadrant jumbo biopsies (every 1 cm) with biopsies of mucosal abnormalities (the Seattle protocol) is considered to be the optimal method for detecting early cancers in patients with high-grade dysplasia, although it has never been validated. This study aimed to determine the frequency of unsuspected carcinoma at esophagectomy in Barrett's esophagus patients with high-grade dysplasia who underwent the Seattle protocol and to compare the findings with those of a less rigorous biopsy protocol.

METHODS

Thirty-three patients with high-grade dysplasia underwent esophagectomy. None had obvious mass lesions at preoperative endoscopy. Patients were divided into group 1 (preoperative surveillance biopsies according to Seattle protocol) and group 2 (4 quadrant biopsies every 2 cm). Preoperative and postoperative diagnoses were confirmed by 2 expert gastrointestinal pathologists.

RESULTS

Unsuspected intramucosal cancer was found in 8 of 20 (40%) patients in group 1 versus 4 of 13 (30%) in group 2 (P = .6). Preoperative mucosal nodularity was observed in 4 of 8 (50%) postoperative intramucosal cancers from group 1 versus 3 of 4 (75%) from group 2. Multifocal high-grade dysplasia was seen preoperatively in 7 of 8 (87.5%) postoperative intramucosal cancers in group 1 versus 2 of 4 (50%) in group 2. No patient had submucosal cancer or lymph node metastases at surgery.

CONCLUSIONS

Intense preoperative biopsy sampling by the Seattle protocol does not more reliably predict the detection of cancer at the time of esophagectomy than a less intensive surveillance protocol. This calls into question the concept that extensive sampling with the Seattle protocol consistently detects early cancers arising in Barrett's esophagus patients with high-grade dysplasia.

Low prevalence of submucosal invasive carcinoma at esophagectomy for high-grade dysplasia or intramucosal adenocarcinoma in Barrett's esophagus: a 20-year experience

BACKGROUND

The rate of occult adenocarcinoma at esophagectomy in patients with Barrett's esophagus (BE) and high-grade dysplasia (HGD) has been reported to be approximately 40%. Recently, it has been suggested that this risk may be overestimated.

OBJECTIVE

Our purpose was to determine the rate of submucosal invasive adenocarcinoma in patients undergoing esophagectomy for BE after biopsy diagnosis of HGD or intramucosal carcinoma (IMC). A secondary aim was to identify clinical risk factors for submucosal invasive adenocarcinoma in these patients.

DESIGN

A retrospective study.

SETTING

Tertiary referral center.

PATIENTS

All patients with preoperative BE with HGD or IMC treated with esophagectomy over a 20 year period.

INTERVENTIONS

Esophagectomy.

MAIN OUTCOME MEASUREMENTS

Submucosal invasive adenocarcinoma at esophagectomy.

RESULTS

Sixty patients were included (41 with preoperative HGD, 19 with preoperative IMC). The overall rate of submucosal invasive carcinoma was 6.7% (95% CI, 1.8%-16.2%) (n = 4), with a 5% rate of submucosal invasion in patients with preoperative HGD and 11% for patients with preoperative IMC. All 4 patients with submucosal invasion at esophagectomy had either nodular or ulcerated mucosa on preoperative endoscopy. The 1-year and 5-year all-cause risks of death for the entire cohort were 1.9% and 10.9%, respectively.

LIMITATIONS

Retrospective study.

CONCLUSIONS

The rate of submucosal invasive adenocarcinoma at esophagectomy in BE patients with HGD or IMC on biopsy is much lower than 40%. After adequate sampling and staging, patients with BE with HGD and IMC, especially those without endoscopically visible lesions, can potentially be treated by nonsurgical (local) therapies.

Epidemiology and biology of esophageal cancer

In the United States and other Western countries, there has been a remarkable change in the epidemiology of esophageal cancer over the past 50 years. Adenocarcinoma of the esophagus and gastroesophageal junction has replaced squamous cell as the most common type of esophageal cancer in the United States, and the incidence of esophageal adenocarcinoma is increasing faster than that of any other malignancy. Risk factors include gastroesophageal reflux disease and obesity. The increasing incidence of esophageal adenocarcinoma and a greater understanding of its underlying biology provide opportunities to devise treatment strategies that maximize survival and minimize morbidity. However, rational use of available endoscopic procedures, esophagectomy, and chemotherapy and radiotherapy requires a comprehensive understanding of the disease.

Update on the diagnosis and treatment of Barrett esophagus and related neoplastic precursor lesions

CONTEXT

At present, Barrett esophagus is the most common cause of esophageal adenocarcinoma. In the past 20 years, the incidence of esophageal adenocarcinoma in white males has exceeded that of tumors of the colorectum, lung, prostate, and skin.

OBJECTIVES

To (1) provide an evidence-based review of the diagnosis, classification, and histologic differentiation of Barrett esophagus from gastric carditis, (2) provide a summary of the key pathologic features of precursor lesions, such as dysplasia, and (3) evaluate adjunctive markers of dysplasia and predictive markers for the development of cancer. The natural history and risk of cancer in patients with Barrett esophagus is also reviewed.

DATA SOURCES

For this review, selected published peer reviewed articles were chosen from a search through PubMed between the years 1970 and 2007.

CONCLUSIONS

The current definition of Barrett esophagus is partially flawed because not all cases are endoscopically recognizable, nongoblet epithelium is biologically intestinalized, and determination of the presence or absence of goblet cells is susceptible to sampling error. Differentiation of ultrashort segment Barrett esophagus from chronic gastric carditis can be accomplished, in a minority of cases, by evaluating for the presence or absence of histologic features that are known to be associated with Barrett esophagus. Dysplasia in Barrett esophagus begins in the crypt bases and then extends more superficially to include the upper portions of the crypts and surface epithelium. Low- and high-grade dysplasia are distinguished by the presence of marked cytologic and/or architectural abnormalities in the latter compared with the former. There are few, if any, reliable adjunctive diagnostic techniques that can help differentiate nondysplastic from dysplastic epithelium. However, alpha-methylacyl coenzyme A racemase staining has been shown to be useful in 2 separate studies. Both low- and high-grade dysplasia are progressive lesions, and in general, the extent of dysplasia, particularly low grade, is a strong risk factor for progression to carcinoma. Of all the biologic and genetic biomarkers studied to date, evaluation of DNA content is the most reliable and specific. The management of patients with dysplasia is variable among institutions and ranges from aggressive surveillance, endoscopic mucosal resection, mucosal ablation, or total esophagectomy.

Histological assessment of oesophageal columnar mucosa

This review presents the pathological features of Barrett's oesophagus, with an emphasis on the role of pathologists in the diagnosis, surveillance and treatment of the disease. The diagnosis of Barrett's oesophagus is based both on endoscopy and histology. The surveillance of patients relies on systematic biopsy sampling, looking for dysplasia - intraepithelial neoplasia. Well established classifications of dysplasia are now used by pathologists, but there remain problems with this marker. Therefore, many alternative biomarkers have been proposed, that remain of limited interest in daily practice, including DNA-ploidy, proliferation markers, and p53 abnormalities. Endoscopic improvements already allow a better selection of biopsies, and it may be that new technologies will allow 'virtual biopsies'. The role of pathologists is now extended to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection.

Should patients with Barrett's oesophagus be kept under surveillance? The case for

Oesophageal adenocarcinoma is associated with high mortality rates and its incidence is increasing more rapidly than any other gastrointestinal cancer in the Western world. Several factors, including gastro-oesophageal reflux disease, smoking, alcohol and male gender, are associated with oesophageal adenocarcinoma but none can be used to identify accurately those individuals who will develop adenocarcinoma. It is generally accepted that oesophageal adenocarcinoma arises predominantly in Barrett's oesophagus and it is arguable that Barrett's oesophagus is currently the only clinically useful predictor of oesophageal adenocarcinoma. Surveillance - periodic testing to detect adenocarcinoma or its precursor, high grade dysplasia - is widely recommended for patients with Barrett's oesophagus with the aim of reducing mortality from oesophageal adenocarcinoma. The annual incidence of oesophageal adenocarcinoma in patients with Barrett's oesophagus is 0.5%-1.0% although there is marked variation between studies, attributable variously to publication bias, concurrent acid suppression therapy and differences in patient characteristics. There is limited evidence that surveillance reduces the incidence of oesophageal adenocarcinoma or consequent mortality and the cause of death for patients undergoing surveillance is often unrelated to oesophageal disease. There are, nonetheless, observational studies which suggest that surveillance is associated with earlier detection of malignancy and a reduction in mortality; in addition, data from modelling studies suggest that surveillance can be cost-effective. Furthermore, the advent of new, non-surgical treatments (endoscopic mucosal resection, photodynamic therapy, argon plasma coagulation) for high grade dysplasia and early cancer has reduced the risks associated with therapy for disease detected during surveillance. Surveillance programs have high drop out rates and, for patients who continue surveillance, adherence to standard, published protocols is highly variable. The establishment of specialist Barrett's oesophagus surveillance programs, with coordinator support, has considerable potential to improve adherence to current guidelines, pending the acquisition and publication of data from ongoing studies of chemoprophylaxis and surveillance in the management of Barrett's oesophagus. In consequence, although there is a paucity of data providing unequivocal demonstration of benefit, there is no proof that surveillance is ineffective. It is, therefore, appropriate to offer surveillance for Barrett's oesophagus in accordance with locally-applicable published guidelines after a full informed discussion of the risks and benefits of surveillance and therapy; continued participation should be reviewed regularly to accommodate changes in the patient's health and expectations.

Is the risk of concomitant invasive esophageal cancer in high-grade dysplasia in Barrett's esophagus overestimated?

BACKGROUND & AIMS

Recent studies have claimed long neoplasia-free survival rates with endoscopic mucosal resection of high-grade dysplasia (HGD) in Barrett's esophagus (BE). However, reports have contended that approximately 40% of patients who have esophagectomy for HGD have occult invasive cancer. The aim of this study was to use explicit criteria to determine the true prevalence of invasive adenocarcinoma in reports of patients who had esophagectomy for HGD in BE.

METHODS

Studies reporting rates of esophageal cancer in patients who underwent esophagectomy for HGD in BE were gathered using MEDLINE and PUBMED. We defined invasive esophageal adenocarcinoma (IEAC) as tumor with submucosal invasion or beyond. Intramucosal carcinoma (IMC) was not considered IEAC.

RESULTS

Twenty-three articles were selected for analysis. Most investigators reported rates of invasive cancer in the esophagectomy specimen, and the pooled average was 39.9% among the 441 patients who underwent an esophagectomy for HGD. Reported rates varied from 0% to 73%. A total of 267 patients had American Joint Committee on Cancer stage 0 postoperatively, 132 patients had stage I, 23 patients had stage IIa, 10 patients had stage IIb, and 9 patients had stage III. Fourteen studies provided differentiation between intramucosal and submucosal invasion. Among 213 patients, only 12.7% had IEAC, whereas 87.3% had HGD or IMC. The IEAC rate of 11% among patients with visible lesions is greater than the rate of 3% among patients with no visible lesion.

CONCLUSIONS

By using strict pathologic definitions of invasive disease, the present study indicates the true prevalence of IEAC in BE and HGD may have been overestimated significantly. Separating IMC from IEAC is clinically relevant because endoscopic techniques potentially may treat IMC.

Neoplastic precursor lesions in Barrett's esophagus

Barrett's esophagus, currently defined as endoscopically apparent columnar metaplasia of the esophagus with histologic documentation of goblet cells, is the precursor to esophageal adenocarcinoma. However, not all patients with this disorder require intensive surveillance. Pathologic diagnosis and grading of dysplasia in mucosal biopsies remains the best and most widely used method of determining which patients are at highest risk for neoplastic progression. The task of diagnosing dysplasia suffers from considerable interobserver variability. Therefore, consultation with expert gastrointestinal pathologists to confirm the diagnosis of dysplasia before definitive management is highly advisable. Adjunctive methods to improve reproducibility, such as immunostaining for alpha-methylacyl-CoA racemase, show promise but require confirmation in larger studies. This article focuses on dysplasia in Barrett's esophagus in terms of its classification, pathologic diagnostic criteria, limitations, natural history, and treatment.

[Evaluation of dysplasia in gastrointestinal diseases]

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

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.

Extent of low-grade dysplasia is a risk factor for the development of esophageal adenocarcinoma in Barrett's esophagus

OBJECTIVES

Previous studies that evaluated extent of high-grade dysplasia (HGD) as a risk factor for esophageal adenocarcinoma (EA) in Barrett's esophagus (BE) were conflicting, and no prior study has evaluated extent of low-grade dysplasia (LGD) as a risk factor. The aim of this discovery study was to evaluate the hypothesis that extent of LGD and HGD are risk factors for progression to EA.

METHODS

We evaluated baseline biopsies from 77 BE patients with dysplasia including 44 who progressed to EA and 33 who did not progress during follow-up. The total numbers of LGD and HGD crypts were determined separately by counting all crypts and the extent of LGD, HGD, and total dysplasia were correlated with EA outcome.

RESULTS

Thirty-one and 46 patients had a maximum diagnosis of LGD and HGD, respectively. When the crypts were stratified by dysplasia grade, the mean number of LGD crypts per patient was borderline higher in progressors (93.9) compared with nonprogressors (41.2, P= 0.07), and the mean proportion of LGD crypts per patient was significantly higher in progressors (46.4%vs 26.0%, P= 0.037). Neither the mean number of HGD crypts per patient (P= 0.14) nor the mean proportion of HGD crypts per patient (P= 0.20) was significantly associated with EA outcome.

CONCLUSIONS

The extent of LGD is a significant risk factor for the development of EA in BE in this study. Although the presence of HGD is significantly associated with a greater relative risk for development of EA, the extent of HGD was not an independent risk factor for progression.

Extent of low-grade dysplasia in Barrett's esophagus: is it useful for risk stratification?

Low-grade dysplasia remains one of the great enigmas of Barrett's esophagus. Limited information is available on the natural history of this lesion, and studies suggest that cancer risk in patients with low-grade dysplasia is intermediate between that of intestinal metaplasia without dysplasia and high-grade dysplasia. Natural history studies of low-grade dysplasia are hampered by problems with interobserver variability among pathologists and sampling variability among endoscopists. To date, the extent of low-grade dysplasia has not been examined as a potential risk factor for the subsequent development of adenocarcinoma. Srivastava et al., in this issue of the American Journal of Gastroenterology, found that the extent of low-grade dysplasia, as measured by several different methods, was a risk factor for progression to cancer. While these findings are novel and provocative, it is premature to request your pathologist to count the number of crypts or biopsies with low-grade dysplasia just yet. However, these findings, if confirmed by studies utilizing a simpler measure of the extent of low-grade dysplasia, may help us determine the prognostic significance of this lesion in the future.

Barrett's oesophagus?a pathologist's view

Barrett's oesophagus, a precancerous condition for oesophageal adenocarcinoma, detected on endoscopy and confirmed on histology, shows intestinal metaplasia of the lower oesophagus. The significance of microscopic foci of intestinal metaplasia at the gastro-oesophageal junction, corresponding either to so-called 'ultrashort' segment Barrett's oesophagus, or to carditis with intestinal metaplasia, is still a matter of debate. The surveillance of patients with Barrett's oesophagus is still based on systematic biopsy sampling of Barrett's mucosa on endoscopy, looking for dysplasia. Although well-established classifications of dysplasia are now used by most pathologists, there remain numerous problems with this subjective marker (sampling, diagnostic reproducibility, natural history, etc). Therefore, many alternative biomarkers have been proposed, but only DNA aneuploidy, proliferation markers and p53 loss of heterozygosity/overexpression have been shown to be of some use at the present time. Some endoscopic improvements already allow a better selection of biopsies, and it may be that in future new technologies will allow 'virtual biopsies'. On the other hand, the role of pathologists now extends to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection.

Diagnosis and grading of dysplasia in Barrett's oesophagus

This review focuses on the pathological features of dysplasia in Barrett's oesophagus. Two categorisation schemes are used for grading dysplasia in the gastrointestinal tract, including Barrett's oesophagus. The inflammatory bowel disease dysplasia morphology study group system is the one most commonly used in the USA. However, some European and most far Eastern countries use the Vienna classification system, which uses the term "non-invasive neoplasia" instead of low-grade dysplasia (LGD) or high-grade dysplasia (HGD) and also uses the term "suspicious for invasive carcinoma" for lesions that show equivocal cytological or architectural features of tissue invasion. The degree of dysplasia is based on a combination of cytological and architectural atypia. However, the precise number of HGD crypts that is necessary to upgrade a biopsy from LGD to HGD has never been investigated and varies widely among expert gastrointestinal pathologists. The extent of dysplasia, particularly LGD, has also been recognised recently as an important prognostic parameter in Barrett's oesophagus. Other problematic areas of dysplasia interpretation include differentiation of regenerating epithelium versus LGD and separating HGD from carcinoma. Dysplasia associated with macroscopically visible lesions, such as ulcers, nodules or polyps, carry a high risk of synchronous or metachronous adenocarcinoma. Recently, immunostaining for alpha-methylacyl-CoA-racemase has been shown to have a high degree of specificity for detection of dysplasia in Barrett's oesophagus and may be used to help distinguish negative from positive biopsies in this condition. In this review, the problematic areas in dysplasia interpretation are outlined and a specific approach to these issues is discussed.

Emerging aspects of oesophageal and gastro-oesophageal junction cancer histopathology - an update for the surgical oncologist

Adenocarcinoma of the oesophagus and gastro-oesophageal junction are rapidly increasing in incidence and have a well described sequence of carcinogenesis: the Barrett's metaplasia-dysplasia-adenocarcinoma sequence. During recent years there have been changes in the knowledge surrounding disease progression, cancer management and histopathology specimen reporting. Tumours around the gastro-oesophageal junction (GOJ) pose several specific challenges. Numerous difficulties arise when the existing TNM staging systems for gastric and oesophageal cancers are applied to GOJ tumours. The issues facing the current TNM staging and GOJ tumour classification systems are reviewed in this article. Recent evidence regarding the importance of several histopathologically derived prognostic factors, such as circumferential resection margin status and lymph node metastases, have implications for specimen reporting. With the rising use of multimodal treatments for oesophageal cancer it is important that the response of the tumour to this therapy is carefully documented pathologically. In addition, several controversial and novel areas such as endoscopic mucosal resection, lymph node micrometastases and the sentinel node concept are being studied. We aim to review these aspects, with special relevance to oesophageal and gastro-oesophageal cancer specimen reporting, to update the surgical oncologist with an interest in upper gastrointestinal cancer.

Surgical aspects of the patient with high-grade dysplasia

The incidence of esophageal cancer has increased dramatically in the Western population in the last 2 decades. In 1975, about three fourths of the esophageal neoplasms were squamous cell carcinomas and the remainder were adenocarcinomas. During the last 2 to 3 decades, this pattern has changed dramatically and the incidence of squamous cell carcinomas has declined while the incidence of adenocarcinomas has increased. The reason for this dramatic increase is not clear, but gastro esophageal reflux disease, obesity and Barrett's esophagus have been identified as risk factors. High grade dysplasia in Barrett's esophagus is a premalignant condition which can progress to invasive adenocarcinoma. In this article, we discuss the natural history of high grade dysplasia (HGD), difficulties in the diagnosis, the incidence of adenocarcinoma in resected specimens and the surgical aspects in the treatment of HGD, including minimally invasive esophagectomy.