A Pilot Study on Automatic Three-Dimensional Quantification of Barrett's Esophagus for Risk Stratification and Therapy Monitoring

BACKGROUND & AIMS

Barrett's epithelium measurement using widely accepted Prague C&M classification is highly operator dependent. We propose a novel methodology for measuring this risk score automatically. The method also enables quantification of the area of Barrett's epithelium (BEA) and islands, which was not possible before. Furthermore, it allows 3-dimensional (3D) reconstruction of the esophageal surface, enabling interactive 3D visualization. We aimed to assess the accuracy of the proposed artificial intelligence system on both phantom and endoscopic patient data.

METHODS

Using advanced deep learning, a depth estimator network is used to predict endoscope camera distance from the gastric folds. By segmenting BEA and gastroesophageal junction and projecting them to the estimated mm distances, we measure C&M scores including the BEA. The derived endoscopy artificial intelligence system was tested on a purpose-built 3D printed esophagus phantom with varying BEAs and on 194 high-definition videos from 131 patients with C&M values scored by expert endoscopists.

RESULTS

Endoscopic phantom video data demonstrated a 97.2% accuracy with a marginal ± 0.9 mm average deviation for C&M and island measurements, while for BEA we achieved 98.4% accuracy with only ±0.4 cm2 average deviation compared with ground-truth. On patient data, the C&M measurements provided by our system concurred with expert scores with marginal overall relative error (mean difference) of 8% (3.6 mm) and 7% (2.8 mm) for C and M scores, respectively.

CONCLUSIONS

The proposed methodology automatically extracts Prague C&M scores with high accuracy. Quantification and 3D reconstruction of the entire Barrett's area provides new opportunities for risk stratification and assessment of therapy response.

Massively Parallel Sequencing of Esophageal Brushings Enables an Aneuploidy-Based Classification of Patients With Barrett's Esophagus

BACKGROUND & AIMS

Aneuploidy has been proposed as a tool to assess progression in patients with Barrett's esophagus (BE), but has heretofore required multiple biopsies. We assessed whether a single esophageal brushing that widely sampled the esophagus could be combined with massively parallel sequencing to characterize aneuploidy and identify patients with disease progression to dysplasia or cancer.

METHODS

Esophageal brushings were obtained from patients without BE, with non-dysplastic BE (NDBE), low-grade dysplasia (LGD), high-grade dysplasia (HGD), or adenocarcinoma (EAC). To assess aneuploidy, we used RealSeqS, a technique that uses a single primer pair to interrogate ∼350,000 genome-spanning regions and identify specific chromosome arm alterations. A classifier to distinguish NDBE from EAC was trained on results from 79 patients. An independent validation cohort of 268 subjects was used to test the classifier at distinguishing patients at successive phases of BE progression.

RESULTS

Aneuploidy progression was associated with gains of 1q, 12p, and 20q and losses on 9p and 17p. The entire chromosome 8q was often gained in NDBE, whereas focal gain of 8q24 was identified only when there was dysplasia. Among validation subjects, a classifier incorporating these features with a global measure of aneuploidy scored positive in 96% of EAC, 68% of HGD, but only 7% of NDBE.

CONCLUSIONS

RealSeqS analysis of esophageal brushings provides a practical and sensitive method to determine aneuploidy in BE patients. It identifies specific chromosome changes that occur early in NDBE and others that occur late and mark progression to dysplasia. The clinical implications of this approach can now be tested in prospective trials.

Is subtyping of intestinal metaplasia in the upper gastrointestinal tract a worthwhile exercise? An evaluation of current mucin histochemical stains

Intestinal metaplasia is a premalignant condition that occurs in the upper gastrointestinal tract and can be subdivided into three types (I, II and III). Previous studies suggest that type III carries the highest cancer risk. The high iron diamine/alcian blue (HID/AB) technique traditionally has been used to identify this subtype; however, the technique uses reagents that are toxic and potentially carcinogenic. Therefore, in this study we evaluate various alternative histochemical techniques. Our results indicated that the only suitable alternative is Gomori's aldehyde fuchsin/AB technique. The study also revealed that subtyping of intestinal metaplasia is a subjective procedure, open to varying interpretation. Consequently, we suggest that previous work linking cancer risk to metaplasia subtypes should be viewed with some circumspection.

Simplified classification of capillary pattern in Barrett esophagus using magnifying endoscopy with narrow band imaging: implications for malignant potential and interobserver agreement

The classification of Barrett esophagus (BE) using magnifying endoscopy with narrow band imaging (ME-NBI) is not widely used in clinical settings because of its complexity. To establish a new simplified available classification using ME-NBI.We conducted a cross-sectional study in a single-referral center. One hundred eight consecutive patients with BE using ME-NBI and crystal violet (CV) chromoendoscopy, and histological findings were enrolled. BE areas observed by ME-NBI were classified as type I or II on the basis of capillary pattern (CP), and as closed or open type on the basis of a mucosal pit pattern using CV chromoendoscopy; then, biopsy samples were obtained. We evaluated the relation between CP and pit pattern, expression of the factors with malignant potential, percentage of microvascular density, and interobserver agreement.One hundred thirty lesions from 91 patients were analyzed. Type II CP had more open type pit pattern areas and significantly greater microvascular density than type I. The presence of dysplasia, specialized intestinal metaplasia, expressions of COX-2, CDX2, and CD34, and PCNA index were significantly higher in type II, whereas the multivariate analysis showed that type II was the best predictor for the presence of dysplasia (OR 11.14), CD34 expression (OR 3.60), and PCNA (OR 3.29). Interobserver agreement for this classification was substantial (κ = 0.66).A simplified CP classification based on observation with ME-NBI is presented. Our results indicate that the classification may be useful for surveillance of BE with high malignant potential.

Radiofrequency ablation vs endoscopic surveillance for patients with Barrett esophagus and low-grade dysplasia: a randomized clinical trial

IMPORTANCE

Barrett esophagus containing low-grade dysplasia is associated with an increased risk of developing esophageal adenocarcinoma, a cancer with a rapidly increasing incidence in the western world.

OBJECTIVE

To investigate whether endoscopic radiofrequency ablation could decrease the rate of neoplastic progression.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter randomized clinical trial that enrolled 136 patients with a confirmed diagnosis of Barrett esophagus containing low-grade dysplasia at 9 European sites between June 2007 and June 2011. Patient follow-up ended May 2013.

INTERVENTIONS

Eligible patients were randomly assigned in a 1:1 ratio to either endoscopic treatment with radiofrequency ablation (ablation) or endoscopic surveillance (control). Ablation was performed with the balloon device for circumferential ablation of the esophagus or the focal device for targeted ablation, with a maximum of 5 sessions allowed.

MAIN OUTCOMES AND MEASURES

The primary outcome was neoplastic progression to high-grade dysplasia or adenocarcinoma during a 3-year follow-up since randomization. Secondary outcomes were complete eradication of dysplasia and intestinal metaplasia and adverse events.

RESULTS

Sixty-eight patients were randomized to receive ablation and 68 to receive control. Ablation reduced the risk of progression to high-grade dysplasia or adenocarcinoma by 25.0% (1.5% for ablation vs 26.5% for control; 95% CI, 14.1%-35.9%; P < .001) and the risk of progression to adenocarcinoma by 7.4% (1.5% for ablation vs 8.8% for control; 95% CI, 0%-14.7%; P = .03). Among patients in the ablation group, complete eradication occurred in 92.6% for dysplasia and 88.2% for intestinal metaplasia compared with 27.9% for dysplasia and 0.0% for intestinal metaplasia among patients in the control group (P < .001). Treatment-related adverse events occurred in 19.1% of patients receiving ablation (P < .001). The most common adverse event was stricture, occurring in 8 patients receiving ablation (11.8%), all resolved by endoscopic dilation (median, 1 session). The data and safety monitoring board recommended early termination of the trial due to superiority of ablation for the primary outcome and the potential for patient safety issues if the trial continued.

CONCLUSIONS AND RELEVANCE

In this randomized trial of patients with Barrett esophagus and a confirmed diagnosis of low-grade dysplasia, radiofrequency ablation resulted in a reduced risk of neoplastic progression over 3 years of follow-up.

TRIAL REGISTRATION

trialregister.nl Identifier: NTR1198.

Meta-analysis of Barrett’s esophagus in China

AIM: To investigate the epidemiology and characteristics of Barrett’s esophagus (BE) in China and compare with cases in the west.

METHODS: Studies were retrieved from the China National Knowledge Infrastructure and PubMed databases using the terms “Barrett” and “Barrett AND China”, respectively, as well as published studies about BE in China from 2000 to 2011. The researchers reviewed the titles and abstracts of all search results to determine whether or not the literature was relevant to the current topic of this research. The references listed in the studies were also searched. Inclusion and exclusion criteria for the literature were appropriately established, and the data reported in the selected studies were analyzed. Finally, a meta-analysis was performed.

RESULTS: The current research included 3873 cases of BE from 69 studies. The endoscopic detection rate of BE in China was 1%. The ratio of male to female cases was 1.781 to 1, and the average age of BE patients was 49.07 ± 5.09 years. Island-type and short-segment BE were the most common endoscopic manifestations, accounting for 4.48% and 80.3%, respectively, of all cases studied. Cardiac-type BE was observed in 40.0% of the cases, representing the most common histological characteristic of the condition. Cancer incidence was 1.418 per 1000 person-years.

CONCLUSION: Average age of BE patients in China is lower than in Western countries. Endoscopic detection and cancer incidence were also lower in China.

Assessment of the diagnostic performance and interobserver variability of endocytoscopy in Barrett’s esophagus: A pilot ex-vivo study

AIM: To investigate a classification of endocytoscopy (ECS) images in Barrett’s esophagus (BE) and evaluate its diagnostic performance and interobserver variability.

METHODS: ECS was applied to surveillance endoscopic mucosal resection (EMR) specimens of BE ex-vivo. The mucosal surface of specimen was stained with 1% methylene blue and surveyed with a catheter-type endocytoscope. We selected still images that were most representative of the endoscopically suspect lesion and matched with the final histopathological diagnosis to accomplish accurate correlation. The diagnostic performance and inter-observer variability of the new classification scheme were assessed in a blinded fashion by physicians with expertise in both BE and ECS and inexperienced physicians with no prior exposure to ECS.

RESULTS: Three staff physicians and 22 gastroenterology fellows classified eight randomly assigned unknown still ECS pictures (two images per each classification) into one of four histopathologic categories as follows: (1) BEC1-squamous epithelium; (2) BEC2-BE without dysplasia; (3) BEC3-BE with dysplasia; and (4) BEC4-esophageal adenocarcinoma (EAC) in BE. Accuracy of diagnosis in staff physicians and clinical fellows were, respectively, 100% and 99.4% for BEC1, 95.8% and 83.0% for BEC2, 91.7% and 83.0% for BEC3, and 95.8% and 98.3% for BEC4. Interobserver agreement of the faculty physicians and fellows in classifying each category were 0.932 and 0.897, respectively.

CONCLUSION: This is the first study to investigate classification system of ECS in BE. This ex-vivo pilot study demonstrated acceptable diagnostic accuracy and excellent interobserver agreement.

Investigation of relationships among gastroesophageal reflux disease subtypes using narrow band imaging magnifying endoscopy

AIM: To investigate the relationships among subtypes of gastroesophageal reflux disease (GERD) using narrow band imaging (NBI) magnifying endoscopy.

METHODS: A reflux disease questionnaire was used to screen 120 patients representing the three subtypes of GERD (n = 40 for each subtypes): nonerosive reflux disease (NERD), reflux esophagitis (RE) and Barrett’s esophagus (BE). NBI magnifying endoscopic procedure was performed on the patients as well as on 40 healthy controls. The demographic and clinical characteristics, and NBI magnifying endoscopic features, were recorded and compared among the groups. Targeted biopsy and histopathological examination were conducted if there were any abnormalities. SPSS 18.0 software was used for all statistical analysis.

RESULTS: Compared with healthy controls, a significantly higher proportion of GERD patients had increased number of intrapapillary capillary loops (IPCLs) (78.3% vs 20%, P < 0.05), presence of microerosions (41.7% vs 0%, P < 0.05), and a non-round pit pattern below the squamocolumnar junction (88.3% vs 30%, P < 0.05). The maximum (228 ± 4.8 vs 144 ± 4.7, P < 0.05), minimum (171 ± 3.8 vs 103 ± 4.4, P < 0.05), and average (199 ± 3.9 vs 119 ± 3.9, P < 0.05) numbers of IPCLs/field were also significantly greater in GERD patients. However, comparison among groups of the three subtypes showed no significant differences or any linear trend, except that microerosions were present in 60% of the RE patients, but in only 35% and 30% of the NERD and BE patients, respectively (P < 0.05).

CONCLUSION: Patients with GERD, irrespective of subtype, have similar micro changes in the distal esophagus. The three forms of the disease are probably independent of each other.

Magnifying endoscopy for the diagnosis of specialized intestinal metaplasia in short-segment Barrett’s esophagus

AIM: To determine whether magnified observation of short-segment Barrett’s esophagus (BE) is useful for the detection of specialized intestinal metaplasia (SIM).

METHODS: Thirty patients with suspected short-segment BE underwent magnifying endoscopy up to × 80. The magnified images were analyzed with respect to their pit-patterns, which were simultaneously classified into five epithelial types [I (small round), II (straight), III (long oval), IV (tubular), V (villous)] by Endo’s classification. Then, a 0.5% solution of methylene blue (MB) was sprayed over columnar mucosa. The patterns of the magnified image and MB staining were analyzed. Biopsies were obtained from the regions previously observed by magnifying endoscopy and MB chromoendoscopy.

RESULTS: Three of five patients with a type V (villous) epithelial pattern had SIM, whereas 21 patients with a non-type V epithelial patterns did not have SIM. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of pit-patterns in detecting SIM were 100%, 91.3%, 92.3%, 60% and 100%, respectively (P = 0.004). Three of the 12 patients with positive MB staining had SIM, whereas 14 patients with negative MB staining did not have SIM. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of MB staining in detecting SIM were 100%, 60.9%, 65.4%, 25% and 100%, respectively (P = 0.085). The specificity and accuracy of pit-pattern evaluation were significantly superior compared with MB staining for detecting SIM by comparison with the exact McNemar’s test (P = 0.0391).

CONCLUSION: The magnified observation of a short-segment BE according to the mucosal pattern and its classification can be predictive of SIM.

Detection of endogenous biomolecules in Barrett's esophagus by Fourier transform infrared spectroscopy

Fourier transform infrared (FTIR) spectroscopy provides a unique molecular fingerprint of tissue from endogenous sources of light absorption; however, specific molecular components of the overall FTIR signature of precancer have not been characterized. In attenuated total reflectance mode, infrared light penetrates only a few microns of the tissue surface, and the influence of water on the spectra can be minimized, allowing for the analyses of the molecular composition of tissues. Here, spectra were collected from 98 excised specimens of the distal esophagus, including 38 squamous, 38 intestinal metaplasia (Barrett's), and 22 gastric, obtained endoscopically from 32 patients. We show that DNA, protein, glycogen, and glycoprotein comprise the principal sources of infrared absorption in the 950- to 1,800-cm(-1) regime. The concentrations of these biomolecules can be quantified by using a partial least-squares fit and used to classify disease states with high sensitivity, specificity, and accuracy. Moreover, use of FTIR to detect premalignant (dysplastic) mucosa results in a sensitivity, specificity, positive predictive value, and total accuracy of 92%, 80%, 92%, and 89%, respectively, and leads to a better interobserver agreement between two gastrointestinal pathologists for dysplasia (kappa = 0.72) versus histology alone (kappa = 0.52). Here, we demonstrate that the concentration of specific biomolecules can be determined from the FTIR spectra collected in attenuated total reflectance mode and can be used for predicting the underlying histopathology, which will contribute to the early detection and rapid staging of many diseases.

Grading of dysplasia in Barrett's oesophagus: substantial interobserver variation between general and gastrointestinal pathologists

AIMS

To determine interobserver variation in grading of dysplasia in Barrett's oesophagus (BO) between non-expert general pathologists and expert gastrointestinal pathologists on the one hand and between expert pathologists on the other hand.

METHODS AND RESULTS

In this prospective multicentre study, non-expert and expert pathologists graded biopsy specimens of 920 patients with endoscopic BO, which were blindly reviewed by one member of a panel of expert pathologists (panel experts) and by a second panel expert in case of disagreement on dysplasia grade. Agreement between two of three pathologists was established as the final diagnosis. Analysis was performed by kappa statistics. Due to absence of intestinal metaplasia, 127/920 (14%) patients were excluded. The interobserver agreement for dysplasia [no dysplasia (ND) versus indefinite for dysplasia/low-grade dysplasia (IND/LGD) versus high-grade dysplasia (HGD)/adenocarcinoma (AC)] between non-experts and first panel experts and between initial experts and first panel experts was fair (kappa = 0.24 and kappa = 0.27, respectively), and substantial for differentiation of HGD/AC from ND/IND/LGD (kappa = 0.62 and kappa = 0.58, respectively).

CONCLUSIONS

There was considerable interobserver variability in the interpretation of ND or IND/LGD in BO between non-experts and experts, but also between expert pathologists. This suggests that less subjective markers are needed to determine the risk of developing AC in BO.

Goblet cell mimickers in esophageal biopsies are not associated with an increased risk for dysplasia

CONTEXT

Identification of intestinal-type goblet cells (ITGCs) in hematoxylin-eosin-stained sections of esophageal biopsies is essential for the diagnosis of Barrett metaplasia. However, we have seen cases diagnosed as Barrett metaplasia based solely on cells that pose morphologic similarity to ITGCs on hematoxylin-eosin staining or stain positive with Alcian blue.

OBJECTIVE

To determine the clinical significance of goblet cell mimickers.

DESIGN

Initial biopsies from 78 patients with original diagnosis of Barrett metaplasia negative for dysplasia and a mean follow-up of 72 months were reviewed and reclassified into 3 categories: (1) ITGCs, (2) goblet cell mimickers, or (3) neither. Sections from available paraffin blocks were stained with Alcian blue at pH 2.5. The presence of the different types of cells and positive Alcian blue staining were correlated with each other and evaluated for their significance as predictors of progression to dysplasia.

RESULTS

Goblet cell mimickers were present in 35 cases and were associated with ITGCs in the same biopsy in 23 (66%) of these cases. Intestinal-type goblet cells were present in 56 cases, and the remaining 10 cases, although called Barrett on the original report, did not show either ITGCs or goblet cell mimickers. Only the presence of ITGCs was associated with significant risk for dysplasia (P = .008). Positive Alcian blue staining was not associated with a significant risk for dysplasia.

CONCLUSIONS

Our results indicate that the diagnosis of Barrett metaplasia should be rendered with confidence only when ITGCs are identified on routine hematoxylin-eosin-stained sections.

Prospective evaluation of the macroscopic types and location of early Barrett's neoplasia in 380 lesions

BACKGROUND AND STUDY AIMS

The macroscopic appearance of early gastric cancers, classified according to the Japanese criteria, has been shown to be an important prognostic factor for local endoscopic therapy. No prospective data about the distribution of macroscopic types and their location in early Barrett's neoplasia are available, however. The present study was conducted to evaluate the clinical applicability of this macroscopic classification and to analyze the relative proportions of the different gross types in early Barrett's neoplasms and the correlation between the macroscopic classification and the stage or grade of differentiation.

PATIENTS AND METHODS

A total of 344 patients with 380 Barrett's neoplastic lesions who were referred between October 1996 and September 2005 for endoscopic therapy of early Barrett's high-grade intraepithelial neoplasia and carcinoma were prospectively included in the study. Routine endoscopy prior to endoscopic resection in our center included assessment of the macroscopic type (according to the Japanese classification) and documentation of the radial location of the neoplastic lesions. Images were recorded which were later assessed by six independent reviewers; intra- and interobserver agreement for the assessment of the macroscopic type were calculated using kappa statistics.

RESULTS

The distribution of the lesions by gross type was as follows: type I, n = 49 (13 %); type IIa, n = 139 (37 %); type IIb, n = 106 (28 %); type IIc, n = 17 (4 %); type IIa + c, n = 62 (16 %); type III, n = 7 (2 %). Type IIb lesions seem to be the most favorable type with regard to differentiation and T category ( P < 0.05). The mean kappa value for the interobserver agreement was 0.86 and the mean kappa value for the intraobserver agreement was 0.89. Most lesions were found at the 12 o'clock and 3 o'clock positions.

CONCLUSIONS

Assessment of the macroscopic type may provide important information about the possibility of endoscopic treatment. The harder-to-detect flat lesions are by far the most frequent macroscopic type of neoplastic lesion in Barrett's esophagus.

The development and validation of an endoscopic grading system for Barrett's esophagus: the Prague C & M criteria

BACKGROUND & AIMS

Barrett's esophagus (BE) is a premalignant condition for esophageal adenocarcinoma, its diagnosis relying initially on recognition of a columnar-lined distal esophagus. We aimed to develop and validate explicit, consensus-driven criteria for the endoscopic diagnosis and grading of BE.

METHODS

An international working group agreed on criteria and developed materials for their formal evaluation using video-endoscopic recordings gathered in a standardized manner in 29 patients. The criteria included assessment of the circumferential (C) and maximum (M) extent of the endoscopically visualized BE segment as well as endoscopic landmarks. The recordings were scored according to these criteria by a separate international panel of 29 endoscopists.

RESULTS

The Prague C & M Criteria give explicit guidance on the endoscopic recognition of BE and grading of its extent. The overall reliability coefficients (RC) for the assessment of the C & M extent of the endoscopic BE segment above the gastroesophageal junction were 0.95 and 0.94, respectively. The rates of exact agreement (for C & M values) for pairwise comparisons of individual patient values were 53% and 38%, respectively, whereas the values for agreement within a 2-cm interval were 97% and 95%, respectively. The overall RC for endoscopic recognition of BE >/=1 cm was 0.72, whereas for BE <1 cm, it was 0.22. The RCs for recognizing the location of the gastroesophageal junction and the diaphragmatic hiatus were 0.88 and 0.85, respectively.

CONCLUSIONS

The Prague C & M Criteria have high overall validity for the endoscopic assessment of visualized BE lengths.

Detection and classification of the mucosal and vascular patterns (mucosal morphology) in Barrett's esophagus by using narrow band imaging

BACKGROUND

The detection of the mucosal morphology (ie, mucosal and vascular patterns) in Barrett's esophagus (BE) by magnifying (chromo)endoscopy may improve the distinction of high-grade intraepithelial neoplasia (HGIN) from nondysplastic specialized intestinal metaplasia (SIM). Narrow band imaging (NBI) is a new technique that uses optical filters to enhance the mucosal contrast without the need for chromoendoscopy.

OBJECTIVE

To use NBI for the characterization and the classification of the mucosal morphology in nondysplastic BE and in BE with HGIN.

DESIGN

Descriptive study.

SETTING

Single-center study in a tertiary referral center for the diagnosis and treatment of patients with BE.

PATIENTS

We used NBI with magnifying endoscopy to image and biopsy randomly selected areas in 63 patients with BE. A systematic image and a biopsy specimen evaluation process was followed, including unblinded assessment of an exploratory set of images and biopsy specimens, and blinded evaluation of learning and validation sets.

MAIN OUTCOME MEASUREMENTS

The relationship between the mucosal morphology and the presence of SIM and HGIN.

RESULTS

SIM was characterized by either villous/gyrus-forming patterns (80%), which were mostly regular and had regular vascular patterns, or a flat mucosa with regular normal-appearing long branching vessels (20%). HGIN was characterized by 3 abnormalities: irregular/disrupted mucosal patterns, irregular vascular patterns, and abnormal blood vessels. All areas with HGIN had at least 1 abnormality, and 85% had 2 or more abnormalities. The frequency of abnormalities showed a significant rise with increasing grades of dysplasia. The magnified NBI images had a sensitivity of 94%, a specificity of 76%, a positive predictive value of 64%, and a negative predictive value of 98% for HGIN.

LIMITATIONS

No data on observer agreement.

CONCLUSIONS

NBI with magnification reveals the mucosal morphology characteristics of nondysplastic BE and HGIN, without the need for staining and has a relatively high diagnostic value for HGIN when used for targeted detailed examination of areas of interest.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Rab11a immunohistochemical analysis does not distinguish indefinite, low-, and high-grade dysplasia in Barrett esophagus

Our aim was to determine whether p53 and Rab11a immunoreactivity enhance diagnostic assessment of esophageal dysplasia. Histologic sections from 68 cases of Barrett esophagus obtained as part of a 12-institution study were stained with antibodies to p53 and Rab11a, randomized, and coded. The mucosal surface layer and deeper glands were scored blindly on a semiquantitative scale. The correlations between p53 and Rab11a scoring with the consensus diagnosis of dysplasia were analyzed. The histologic scale was as follows: no dysplasia, indefinite, low-grade dysplasia, high-grade dysplasia, intramucosal carcinoma, and invasive carcinoma. Rab11a staining was most prominent in epithelia negative for dysplasia but with regenerative features. There was an inverse relationship between Rab11a staining and findings of surface dysplasia (P < .02, chi(2)). However, statistical significance largely reflected loss of Rab11a immunoreactivity in intramucosal and invasive carcinoma, which was not a diagnostic dilemma. There was a strong positive correlation of p53 immunoreactivity with an increasing degree of epithelial dysplasia and carcinoma (P < .03, chi(2)). Rab11a immunoreactivity did not enhance the diagnostic assessment of dysplasia in Barrett esophagus. The previously reported positive correlation of p53 immunoreactivity with the presence of dysplasia in Barrett esophagus was confirmed.

[Preface: Recent perspectives of the Barrett's esophagus]

As the prevalence of reflux esophagitis is increasing in Japan, due to increased amount of energy intake and improved hygiene with the reduced H. pylori infection, the number of patients having Barrett's esophagus is also increasing. In the Western countries, adenocarcinoma of the esophagus is rapidly increasing among the white elder male, where the reflux esophagitis is more common. Terminology of Barrett's esophagus is still confusing. Recent proposal of endoscopic evaluation of Barrett's esophagus is based on the endoscopic findings, not histologic findings. In the development of adenocarcinoma of the esophagus, several steps of genetic abnormalities might be involved. We still do not know whether we may experience an increase of adenocarcinoma of the esophagus in Japan or not.

Expression of the high mobility group proteins HMGI(Y) correlates with malignant progression in Barrett's metaplasia

Expression of the high mobility group proteins HMGI(Y) has been shown to be a marker of malignancy in thyroid and pancreatic lesions and to correlate significantly with malignant progression in the colon. The aim of this study was to determine whether HMGI(Y) expression is associated with malignant progression in Barrett's metaplasia (BM). Immunoperoxidase staining for HMGI(Y) was performed on sections of formalin-fixed paraffin-embedded endoscopic esophageal biopsies from 42 patients with BM. These consisted of 19 biopsies negative for dysplasia (ND), 16 with low-grade dysplasia (LGD)/indeterminate for dysplasia (IND), and 7 with high-grade dysplasia (HGD)/adenocarcinoma (CA). The percentage of positive cells was recorded, and nuclear HMGI(Y) immunoreactivity in >10% of the cells was considered positive. Statistical analysis was performed using Fisher's exact test. Positive HMGI(Y) staining was detected in 2 of 19 (11%) cases ND, 5 of 16 (30%) LGD/IND cases, and 7 of 7 (100%) HGD/CA cases. Biopsies with HGD/CA were significantly more likely to be positive for HMGI(Y) than biopsies ND (P < 0.0001) or with LGD/IND (P = 0.0046). We conclude that HMGI(Y) expression is significantly associated with malignant progression in BM. Additional studies are needed to determine whether BM biopsies that are ND or LGD/IND and positive for HMGI(Y) are more likely to progress to adenocarcinoma.

Detection of intestinal metaplasia in distal esophagus and esophagogastric junction by enhanced-magnification endoscopy

BACKGROUND

Standard videoendoscopy identifies columnar-lined esophagus but cannot distinguish intestinal metaplasia from other types of epithelium. Enhanced-magnification endoscopy identifies different mucosal pit patterns. A preliminary study suggested that a type 3 pattern is associated with the presence of intestinal metaplasia. This study assesses the value of enhanced-magnification endoscopy for the detection of intestinal metaplasia in the distal esophagus and esophagogastric junction in patients undergoing diagnostic EGD.

METHODS

Patients undergoing diagnostic endoscopy for upper-GI symptoms underwent enhanced-magnification endoscopy after instillation of 1.5% acetic acid. The enhanced-magnification endoscopy mucosal pattern was classified into 3 types: 1, normal pits; 2, slit-reticular pattern; and 3, gyrus-villous pattern. Preliminary studies indicated that the type 3 pattern was related to intestinal metaplasia. One to 6 biopsies were targeted to areas having a type 3 pattern in columnar-appearing mucosa in the distal esophagus or esophagogastric junction. In the absence of type 3 pattern, one to 8 biopsies were targeted to areas with a type 2 pattern in columnar-appearing mucosa in the distal esophagus or esophagogastric junction.

RESULTS

The overall frequency of intestinal metaplasia in the esophagus and esophagogastric junction was 38.8% (26/67 patients). There was a good correlation between the type 3 pattern and intestinal metaplasia in targeted biopsy specimens (sensitivity 88.5%, specificity 90.2%, positive predictive value 85.2%, negative predictive value 92.5%, overall accuracy 90.0%).

CONCLUSIONS

Enhanced-magnification endoscopy is useful for detection of intestinal metaplasia in distal esophagus and esophagogastric junction.

Defining dysplasia in Barrett esophagus

Histologic grading of esophageal biopsies remains the cornerstone of management in patients with Barrett esophagus. This remains true despite ongoing research into the genetic abnormalities that occur in the setting of intestinal metaplasia, dysplasia, and adenocarcinoma of the esophagus. As of this writing, there are no objective tests that can replace the pathologist's eyes in predicting prognosis in this setting. However, pathologists and clinicians are well aware that the histologic interpretation of biopsies is an inherently subjective practice. The validity of this exercise depends entirely on the experience of the pathologist. Having said that, two interobserver studies on the grading of dysplasia in Barrett esophagus suggest that, if published criteria are adhered to, the histologic grading of dysplasia is a useful tool in patient management. In this review, the updated pathologic criteria for each category of dysplasia are presented, and the results of two large interobserver variability studies are reviewed.

Pathology of Barrett's esophagus by proton magnetic resonance spectroscopy and a statistical classification strategy

BACKGROUND

Barrett's esophagus is thought to be a precursor of adenocarcinoma. The incidence of adenocarcinoma of the lower esophagus in the Western world is rising and accounts for more than 40% of esophageal carcinomas in males. It is not possible to identify which Barrett's patients are at high risk of developing malignancy. Here we applied a statistical classification strategy to the analysis of magnetic resonance spectroscopy and histopathological data from esophageal biopsies to ascertain whether this risk could be identified in Barrett's patients.

METHODS

Tissue specimens from 72 patients (29 noncancer-bearing and 43 cancer-bearing) were analyzed by one-dimensional proton magnetic resonance spectroscopy at 8.5 Tesla. Diagnostic correlation was performed between the magnetic resonance spectra and histopathology. The magnetic resonance magnitude spectra were preprocessed, followed by identification of optimal spectral regions, and were then classified by cross-validated linear discriminant analysis of rank orders of the first derivative of magnetic resonance spectra.

RESULTS

Magnetic resonance spectroscopy combined with a statistical classification strategy analysis distinguished normal esophagus from adenocarcinoma and Barrett's epithelium with an accuracy of 100%. Barrett's epithelium and adenocarcinoma were distinguished with an accuracy of 98.6% but only when 4 of the Barrett's specimens and 7 of the carcinoma specimens, determined to be "fuzzy" (ie, unable to be accurately assigned to either class) were withdrawn. The 7 cancer and 4 Barrett's specimens, determined to be "fuzzy" using the Barrett's versus cancer (B versus C) classifier, were submitted to the other two classifiers (Barrett's versus normal [B versus N] and normal versus cancer [N versus C], respectively). The 4 Barrett's specimens were assigned to Barrett's by the N versus B classifier and to normal (n = 2) or cancer (n = 2) classes by the N versus C classifier. The 7 cancer specimens were crisply assigned to the cancer class (N versus C), or for the B versus N classifier, to the Barrett's class (ie, more similar to Barrett's than to normal tissue). Visual inspection of the spectra from histologically identified Barrett's epithelium showed a gradation from normal to carcinoma.

CONCLUSIONS

Proton magnetic resonance spectroscopy of esophageal biopsies combined with a statistical classification strategy data analysis provides a robust diagnosis with a high degree of accuracy for discriminating normal epithelium from esophageal adenocarcinoma and Barrett's esophagus. Different spectral categories of Barrett's epithelium were identified both by visual inspection and by statistical classification strategy, possibly reflecting the risk of future malignant transformation.

[Risk estimation in Barrett's esophagus: biomolecular marker and histopathologic classification]

The diagnosis of Barrett's esophagus and the different degrees of intraepithelial neoplasia appear to be demanding in several aspects. Current data on genetic alterations involved in the carcinogenesis of Barrett's esophagus are discussed. Several new biomarkers are being tested to help better to determine the risk of cancer development. However, a few immunohistochemical markers have emerged which could be helpful for the differential diagnosis of low- and high-grade intraepithelial neoplasia. Markers which could predict the progression of premalignant Barrett's epithelium to carcinoma are still to be established. At present, the "gold standard" for classifying the malignant potential in Barrett's esophagus is the degree of intraepithelial neoplasia found on standard biopsy protocols.

Gastroesophageal reflux disease--should we adopt a new conceptual framework?

Gastroesophageal reflux disease (GERD) has traditionally been approached as a spectrum of diseases. Over the years, this important concept affected our current understanding of the pathophysiologic mechanisms resulting in GERD. Additionally, it had a profound impact on our therapeutic approach and treatment algorithms. However, literature review reveals that there is scant data to support the spectrum paradigm. Consequently, we propose categorizing GERD into three unique groups of patients: nonerosive reflux disease, erosive esophagitis, and Barrett's esophagus. Thus far, studies have demonstrated very little movement between these groups. Although the spectrum concept focused our attention on esophageal mucosal injury, the new proposed conceptual model shifts our attention to esophageal symptoms. Furthermore, dividing GERD into three unique groups of patients will allow us to concentrate on the different mechanisms that lead to the development of each of these GERD-related disorders and thus help us to focus on the specific therapeutic modalities that will benefit each individual group of patients.

Classification of Barrett's epithelium by magnifying endoscopy

BACKGROUND

The specialized columnar epithelium of Barrett's esophagus can be detected by obtaining random or 4 quadrant biopsy specimens at conventional endoscopy. However, little is known about the fine mucosal structure of specialized columnar epithelium.

METHODS

Thirty patients with Barrett's esophagus were studied by magnifying endoscopy. The fine mucosal pattern (pit pattern) of 67 regions in Barrett's mucosa was recorded and compared with methylene blue staining. Histologic, mucin immunohistologic, and cell proliferation analyses of biopsy specimens were performed in relation to the pit patterns determined by magnifying endoscopy.

RESULTS

Pit pattern was classified into 5 types. Tubular and villous pit patterns were not only characteristics of both specialized columnar epithelium and methylene blue absorption, but also possessed an intestinal mucin phenotype with a high Ki-labeling index, whereas other pit patterns (dot and straight) did not have specialized columnar epithelium and were categorized as the gastric phenotype. The long oval pit pattern had an intermediate phenotype between gastric and intestinal.

CONCLUSIONS

The classification of the superficial mucosal appearance of Barrett's epithelium by magnifying endoscopy reflects not only histologic features but also mucin phenotypes.

Endoscopic assessment of the "Z-line" (squamocolumnar junction) appearance: reproducibility of the ZAP classification among endoscopists

BACKGROUND

The histologic presence of intestinal metaplasia in the esophagus is a prerequisite for the diagnosis of Barrett's esophagus. Thus, use of the term Barrett's esophagus to describe certain endoscopic features in the distal esophagus is inappropriate. There is no accepted classification system for the endoscopic description of the squamocolumnar mucosal junction, the so-called "Z-line." Furthermore, no clear definition of the normal Z-line exists. A classification of the Z-line appearance has been proposed: the ZAP classification. The aim of this study was to assess the reproducibility of this classification.

METHODS

Ten physicians with varying endoscopy experience were presented with 15 endoscopic photographs of the Z-line and were asked to classify them according to the ZAP classification. A second assessment was conducted between 7 and 15 weeks after the first.

RESULTS

The median kappa values were in the range of 0.72 to 0.90 with regard to intraobserver as well as interobserver reproducibility, irrespective of experience with upper endoscopy.

CONCLUSIONS

The intraobserver and interobserver reproducibility of the ZAP classification is substantial and thus it is feasible to use this classification to characterize the appearance of the Z-line at endoscopy.

[Barrett's esophagus: screening and prognosis]

The diagnostic criteria for Barrett's disease have changed very considerably during the last 10 years. Classically, the definition asked for columnar epithelium in the lower esophagus extending for at least 3 cm proximally. Now, the diagnosis rests on the finding of specialised intestinal metaplasia, i.e. columnar epithelium with goblet cells, in the esophagus, regardless of the extension. This is important because it is this type of metaplasia that is associated with an increased risk for the development of esophageal adenocarcinoma and esophageal adenocarcinoma is the tumor with the fastest rising incidence in the western world in recent years. The criteria of the current definition of Barrett's esophagus are described in detail and the implications this change in definition carries for screening and surveillance of patients is discussed.

Bile and acid reflux in long and short segment Barrett's esophagus, and in reflux disease

Gastroesophageal acid reflux (GER) is the primary risk factor for gastroesophageal reflux disease (GERD). In long segment Barrett's esophagus (LSBE) duodenogastroesophageal reflux (DGER) parallels acid reflux. The role of GER and DGER in short segment Barrett's esophagus (SSBE) remains to be determined. The aim of the present prospective study was to investigate the esophageal bile and acid reflux in patients with LSBE, SSBE and patients with GERD. Three groups of patients were studied: Patients with LSBE (n = 12), SSBE (n = 20) and patients with GERD without intestinal metaplasia (n = 33). Subjects underwent esophageal manometry and simultaneous 24-h pH and bile monitoring (Bilitec 2000). The thresholds for GER and DGER were a deMeester score > 14.7 and an absorbance value > 0.2 for 10.9% of total period, respectively. GER did not differ between the groups (p > 0.05). However, DGER differed between patients with LSBE, SSBE and GERD (14.7 vs 2.1 vs 2.1, respectively; p < 0.05). H. pylori status did not influence GER and DGER significantly. In contrast to patients with LSBE the DGER does not seem to play an important role in patients with SSBE and patients with GERD. This result indicates a different etiopathology of both long and short segment Barrett's esophagus.

Definition of Barrett's oesophagus

Barrett's oesophagus is the eponym applied to the columnar epithelium-lined lower oesophagus. In 1976, Paull et al. described three types of columnar epithelia lining the distal oesophagus: a junctional or cardiac-type epithelium, a gastric fundic-type epithelium and a distinctive type of intestinal metaplasia referred to as specialized columnar epithelium. Even the normal oesophagus can be lined by 2 cm of columnar epithelium. To avoid the problem of false-positive diagnoses, arbitrary criteria for the extent of oesophageal columnar lining necessary to include patients in studies of Barrett's oesophagus were established in the early 1980s. The latter criteria require a circumferential segment of columnar lined epithelium of 2 or 3 cm in length. There are, however, a number of technical and conceptual problems related to this approach. The traditional definition excludes shorter segments and tongues of columnar lined epithelium. Only the specialized columnar epithelium defined by intestinal type goblet cells carries an inherent risk of malignancy. Therefore, a number of investigators currently define Barrett's oesophagus as any amount of columnar mucosa in the lower esophagus that has histologic evidence of goblet cells (highlighted in biopsies using the alcian blue pH 2.5 stain). Recently, short segments of specialized intestinal metaplasia in the distal oesophagus ("short segment Barrett's oesophagus") have attracted considerable attention. It has also become clear that intestinal metaplasia can occur at a normally located gastro-oesophageal junction. The etiology and clinical significance (in terms of possible relationship to the adenocarcinoma of the cardia) of this "intestinal metaplasia of the gastric cardia" and its potential relationship to Barrett's oesophagus are not yet completely understood.

Short segment Barrett's esophagus--the need for standardization of the definition and of endoscopic criteria

There has been a recent increase in abstracts and publications reporting intestinal metaplasia in the distal esophagus and cardia. The terms "short segment Barrett's esophagus," "intestinal metaplasia of the esophagogastric junction," and "intestinal metaplasia of the cardia" are being used to describe either similar or different entities. This review article deals with the current data on these issues, the definition of short segment Barrett's esophagus including the endoscopic and histologic criteria, the rationale for separating short segment Barrett's esophagus from intestinal metaplasia of the cardia, and a simple classification of intestinal metaplasia.

The columnar-lined esophagus. History, terminology, and clinical issues

Recently, there has been intense controversy regarding diagnostic criteria for Barrett's esophagus. Some authorities have defined the condition according to an arbitrary extent of esophageal columnar lining, whereas others have felt that the presence of specialized intestinal metaplasia anywhere in the esophagus establishes the diagnosis. This article discusses the problems that arise when either of these diagnostic approaches are used and proposes an alternative classification system for the columnar-lined esophagus.

Prospective long-term endoscopic and histological follow-up of short segment Barrett's esophagus: comparison with traditional long segment Barrett's esophagus

OBJECTIVES

Barrett's esophagus is associated with adenocarcinoma of the cardia and esophagus, regardless of its extent. The aim of this study was to compare the prevalence and incidence of dysplasia and adenocarcinoma in short segment and traditional long segment Barrett's esophagus.

METHODS

Seventy-four patients with short segment Barrett's and 78 with traditional Barrett's entered the study.

RESULTS

There were no significant differences in age or gender between the two groups of patients with Barrett's esophagus. A greater percentage of patients with short segment barrett's were black (p = 0.04). The prevalence of dysplasia at diagnosis in patients with short segment Barrett's was 8.1% versus 24.4% in patients with traditional Barrett's (p < 0.007). Adenocarcinoma was noted at diagnosis only in patients with traditional Barrett's (p < 0.0005). Twenty-six patients with short segment Barrett's and 29 with traditional Barrett's were followed prospectively for 12-40 months. Dysplasia developed during follow-up in two patients with short segment Barrett's and in six patients with traditional Barrett's (p < 0.05). Neither high grade dysplasia nor cancer developed in any patients with short segment Barrett's. High grade dysplasia did develop in two patients with traditional Barrett's esophagus, and mucosal adenocarcinoma developed in one. The frequency of dysplasia on the latest surveillance examination continued to be significantly higher for patients with traditional Barrett's (p = 0.03). Follow-up surveillance biopsy specimens of Barrett's mucosa frequently demonstrated an absence of goblet cells in patients with short segment Barrett's compared with patients with traditional Barrett's (p < 0.0001).

CONCLUSIONS

The prevalence of dysplasia or adenocarcinoma and the incidence of dysplasia in patients with traditional Barrett's esophagus are significantly higher than in patients with short segment Barrett's esophagus. Further prospective surveillance is required to determine whether the incidence of adenocarcinoma in patients with short segment Barrett's esophagus is significantly lower.

Esophageal columnar metaplasia (Barrett's esophagus)

This article explores the historical roots for the present confusion regarding diagnostic criteria for Barrett's esophagus. The author recommends using an alternative classification system for the columnar-lined esophagus that does not rely solely on arbitrary and imprecise endoscopic landmarks and measurements. Endoscopic features that suggest the presence of intestinal metaplasia in the esophagus are discussed and illustrated. The role of endosonography and the endoscopic techniques for ablating the esophageal columnar lining also are considered. Finally, the author lists specific management recommendations for patients who have esophageal columnar metaplasia.

Applications of gastrointestinal endoscopy in infants and children

Gastrointestinal endoscopy has become an integral part of defining and treating gastrointestinal disease in children. Premalignant conditions that have been identified by endoscopy with histologic evaluation include Barrett's esophagus, juvenile polyposis coli, generalized juvenile polyposis, familial polyposis, Gardner's syndrome, and Turcot's syndrome. Advances in endoscopic instrumentation has allowed successful endoscopic retrograde cholangiopancreatography (ERCP) to be performed in infants and children. Therapeutic ERCP has been performed to remove stones, ligate strictures, and place stents. This review focuses on selected advances in gastrointestinal endoscopy and related diseases.

Observer variation in the diagnosis of dysplasia in Barrett's esophagus

The potential value of biopsy surveillance of patients with Barrett's esophagus for dysplasia is diminished by a lack of agreement on the diagnostic criteria for dysplasia. In a preliminary consensus conference, experienced gastrointestinal pathologists from four medical centers agreed on criteria for a five-tiered histologic classification of dysplasia in Barrett's esophagus--negative for dysplasia, indefinite for dysplasia, low-grade dysplasia, high-grade dysplasia, and intramucosal carcinoma. Eight morphologists in the four centers tested the criteria for interobserver agreement by examining a set of coded slides that had been chosen to include some especially difficult interpretative problems in all five histologic classifications. Interobserver agreement of 85 and 87% was achieved in successive reviews when the combined group of high-grade dysplasia and intramucosal carcinoma was compared with the combined group of low-grade dysplasia, indefinite for dysplasia, and negative for dysplasia. Comparison of other groups yielded less agreement. For example, negative for dysplasia could be distinguished from all other diagnoses with an interobserver agreement of 72%. We conclude that experienced gastrointestinal morphologists can diagnose high-grade dysplasia and intramucosal carcinoma with a high degree of agreement and thus can detect those patients who may need immediate rebiopsy or esophageal resection. Either further refinement of histologic criteria or alternate diagnostic methods will be needed to achieve the reproducible diagnosis of indefinite changes and low-grade dysplasia. This is important because patients with such changes theoretically merit closer endoscopic surveillance.