COMPUTER-AIDED DIAGNOSIS IMPROVES CHARACTERIZATION OF BARRETT'S NEOPLASIA BY GENERAL ENDOSCOPISTS.

BACKGROUND & AIMS: Characterization of visible abnormalities in Barrett esophagus (BE) patients can be challenging, especially for unexperienced endoscopists. This results in suboptimal diagnostic accuracy and poor inter-observer agreement. Computer-aided diagnosis (CADx) systems may assist endoscopists. We aimed to develop, validate and benchmark a CADx system for BE neoplasia. METHODS: The CADx system received pretraining with ImageNet with consecutive domain-specific pretraining with GastroNet which includes 5 million endoscopic images. It was subsequently trained and internally validated using 1,758 narrow-band imaging (NBI) images of early BE neoplasia (352 patients) and 1,838 NBI images of non-dysplastic BE (173 patients) from 8 international centers. CADx was tested prospectively on corresponding image and video test sets with 30 cases (20 patients) of BE neoplasia and 60 cases (31 patients) of non-dysplastic BE. The test set was benchmarked by 44 general endoscopists in two phases (phase 1: no CADx assistance; phase 2: with CADx assistance). Ten international BE experts provided additional benchmark performance. RESULTS: Stand-alone sensitivity and specificity of the CADx system were 100% and 98% for images and 93% and 96% for videos, respectively. CADx outperformed general endoscopists without CADx assistance in terms of sensitivity (p=0.04). Sensitivity and specificity of general endoscopist increased from 84% to 96% and 90 to 98% with CAD assistance (p<0.001), respectively. CADx assistance increased endoscopists' confidence in characterization (p<0.001). CADx performance was similar to Barrett experts. CONCLUSION: CADx assistance significantly increased characterization performance of BE neoplasia by general endoscopists to the level of expert endoscopists. The use of this CADx system may thereby improve daily Barrett surveillance.

The use of a real-time computer-aided detection system for visible lesions in the Barrett's esophagus during live endoscopic procedures, a pilot study.

BACKGROUND AND AIMS: In this pilot study we evaluated performance of a recently developed computer-aided detection (CADe) system for Barrett's neoplasia during live endoscopic procedures. METHODS: 15 patients with and 15 without a visible lesion were included in this study. A CAD assisted workflow was employed that included: a slow pullback video recording of the entire Barrett's segment with live CADe assistance, followed by CADe assisted level-based video recordings every 2cm of the Barrett's segment. Outcomes were per patient and per level diagnostic accuracy of the CAD assisted workflow, where the primary outcome was per patient in-vivo CADe sensitivity. RESULTS: In the per patient analyses, the CADe system detected all visible lesions (sensitivity 100%). Per patient CADe specificity was 53%. Per-level sensitivity and specificity of the CADe assisted workflow were 100% and 73%, respectively. CONCLUSION: In this pilot study, the CADe system detected all potentially neoplastic lesions in Barrett's esophagus comparable to an expert endoscopist. Continued refinement of the system may improve specificity. External validation in larger multicenter studies is planned.

Feasibility Study Utilizing NanoString's Digital Spatial Profiling (DSP) Technology for Characterizing the Immune Microenvironment in Barrett's Esophagus Formalin-Fixed Paraffin-Embedded Tissues.

Characterization of the Barrett's esophagus (BE) microenvironment in patients with a known progression status, to determine how it may influence BE progression to esophageal adenocarcinoma (EAC), has been understudied, hindering both the biological understanding of the progression and the development of novel diagnostics and therapies. This study's aim was to determine if a highly multiplex interrogation of the microenvironment can be performed on endoscopic formalin-fixed, paraffin-embedded (FFPE) samples, utilizing the NanoString GeoMx digital spatial profiling (GeoMx DSP) platform and if it can begin to identify the types of immune cells and pathways that may mediate the progression of BE. We performed a spatial proteomic analysis of 49 proteins expressed in the microenvironment and epithelial cells of FFPE endoscopic biopsies from patients with non-dysplastic BE (NDBE) who later progressed to high-grade dysplasia or EAC (n = 7) or from patients who, after at least 5 years follow-up, did not (n = 8). We then performed an RNA analysis of 1812 cancer-related transcripts on three endoscopic mucosal resections containing regions of BE, dysplasia, and EAC. Profiling with GeoMx DSP showed reasonable quality metrics and detected expected differences between epithelium and stroma. Several proteins were found to have an increased expression within NDBE biopsies from progressors compared to non-progressors, suggesting further studies are warranted.

The Tissue Systems Pathology Test Outperforms Pathology Review in Risk Stratifying Patients With Low-Grade Dysplasia.

BACKGROUND & AIMS: Low-grade dysplasia (LGD) is associated with an increased risk of progression in Barrett's esophagus (BE); however, the diagnosis of LGD is limited by substantial interobserver variability. Multiple studies have shown that an objective tissue systems pathology test (TissueCypher Barrett's Esophagus Test, TSP-9), can effectively predict neoplastic progression in patients with BE. This study aimed to compare the risk stratification performance of the TSP-9 test vs benchmarks of generalist and expert pathology. METHODS: A blinded cohort study was conducted in the screening cohort of a randomized controlled trial of patients with BE with community-based LGD. Biopsies from the first endoscopy with LGD were assessed by the TSP-9 test and independently reviewed by 30 pathologists from 5 countries per standard practice. The accuracy of the test and the diagnoses in predicting high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) were compared. RESULTS: A total of 154 patients with BE (122 men), mean age 60.9 ± 9.8 years were studied. Twenty-four patients progressed to HGD/EAC within 5 years (median time of 1.7 years) and 130 did not progress to HGD/EAC within 5 years (median 7.8 years follow-up). The TSP-9 test demonstrated higher sensitivity (71% vs mean 63%, range 33%-88% across 30 pathologists), than the pathology review in detecting patients who progressed (P = .01186). CONCLUSIONS: The TSP-9 test outperformed the pathologists in risk stratifying patients with BE with LGD. Care guided by the test can provide an effective solution to variable pathology review of LGD, improving health outcomes by upstaging care to therapeutic intervention for patients at high risk for progression, while reducing unnecessary interventions in low-risk patients.

A Tissue Systems Pathology Test Outperforms the Standard-of-Care Variables in Predicting Progression in Patients With Barrett's Esophagus.

INTRODUCTION: Objective risk stratification is needed for patients with Barrett's esophagus (BE) to enable risk-aligned management to improve health outcomes. This study evaluated the predictive performance of a tissue systems pathology [TSP-9] test (TissueCypher) vs current clinicopathologic variables in a multicenter cohort of patients with BE. METHODS: Data from 699 patients with BE from 5 published studies on the TSP-9 test were evaluated. Five hundred nine patients did not progress during surveillance, 40 were diagnosed with high-grade dysplasia/esophageal adenocarcinoma (HGD/EAC) within 12 months, and 150 progressed to HGD/EAC after 12 months. Age, sex, segment length, hiatal hernia, original and expert pathology review diagnoses, and TSP-9 risk classes were collected. The predictive performance of clinicopathologic variables and the TSP-9 test was compared, and the TSP-9 test was evaluated in clinically relevant patient subsets. RESULTS: The sensitivity of the TSP-9 test in detecting progressors was 62.3% compared with 28.3% for expert-confirmed low-grade dysplasia (LGD), while the original diagnosis abstracted from medical records did not provide any significant risk stratification. The TSP-9 test identified 57% of progressors with nondysplastic Barrett's esophagus (NDBE) ( P < 0.0001). Patients with NDBE who scored TSP-9 high risk progressed at a similar rate (3.2%/yr) to patients with expert-confirmed LGD (3.7%/yr). The TSP-9 test provided significant risk stratification in clinically low-risk patients (NDBE, female, short-segment BE) and clinically high-risk patients (IND/LGD, male, long-segment BE) ( P < 0.0001 for comparison of high-risk classes vs low-risk classes). DISCUSSION: The TSP-9 test predicts risk of progression to HGD/EAC independently of current clinicopathologic variables in patients with BE. The test provides objective risk stratification results that may guide management decisions to improve health outcomes for patients with BE.

An Automated Tissue Systems Pathology Test Can Standardize the Management and Improve Health Outcomes for Patients With Barrett's Esophagus.

INTRODUCTION: Low-grade dysplasia (LGD) in Barrett's esophagus (BE) is associated with an increased risk of progression to high-grade dysplasia or esophageal adenocarcinoma. However, because of substantial interobserver variability in the diagnosis of LGD, a patient's management plan and health outcome depend largely on which pathologist reviews their case. This study evaluated the ability of a tissue systems pathology test that objectively risk stratifies patients with BE (TissueCypher, TSP-9) to standardize management in a manner consistent with improved health outcomes for patients with BE. METHODS: A total of 154 patients with BE with community-based LGD from the prospectively followed screening cohort of the SURF trial were studied. Management decisions were simulated 500 times with varying generalist (n = 16) and expert (n = 14) pathology reviewers to determine the most likely care plan with or without use of the TSP-9 test for guidance. The percentage of patients receiving appropriate management based on the known progression/nonprogression outcomes was calculated. RESULTS: The percentage of patients with 100% of simulations resulting in appropriate management significantly increased from 9.1% for pathology alone, to 58.4% when TSP-9 results were used with pathology, and further increased to 77.3% of patients receiving appropriate management when only TSP-9 results were used. Use of the test results also significantly increased the consistency of management decisions for patients when their slides were reviewed by different pathologists ( P < 0.0001). DISCUSSION: Management guided by the TSP-9 test can standardize care plans by increasing the early detection of progressors who can receive therapeutic interventions, while also increasing the percentage of nonprogressors who can avoid unnecessary therapy and be managed by surveillance alone.

Degree of crypt atypia correlates with progression to high-grade dysplasia/adenocarcinoma in non-dysplastic Barrett's oesophagus.

AIMS: Patients with non-dysplastic Barrett's oesophagus (BE) often show a wide range of 'atypical' histological features in the bases of the crypts. However, the significance of crypt atypia has never been evaluated, despite prior studies showing the presence of DNA content and other molecular abnormalities in this epithelium. The aim of this study was to evaluate whether the degree of crypt atypia in BE patients without dysplasia correlates with progression to high-grade dysplasia/adenocarcinoma (HGD/EAC). METHODS AND RESULTS: Baseline biopsies from 114 BE patients without dysplasia, 57 who progressed to HGD/EAC (progressors) and 57 who did not progress (non-progressors), were included in the study. Biopsies were evaluated for the degree of basal crypt atypia on a three-point scale according to discrete histological criteria. In non-progressors, 64.9, 31.6 and 3.5% of biopsies had a crypt atypia score of 1, 2 and 3, respectively, with a mean score of 1.39 ± 0.56. The percentage of biopsies with an atypia score of 2 or 3 increased in progressors [42.1, 42.1 and 15.8% of biopsies scored 1, 2 or 3, respectively, with a mean score of 1.74 ± 0.72 (P = 0.004)]. The odds ratio of grade 3 crypt atypia for progression to HGD/EAC was 5.2 (95% confidence interval = 1.1-25.0, P = 0.04) and the findings did not change significantly when the data were analysed according to progression to either HGD or EAC. CONCLUSIONS: This study shows that non-dysplastic crypts in BE are biologically abnormal, suggesting that neoplastic progression begins prior to the onset of dysplasia. The degree of crypt atypia in BE patients without dysplasia correlates with progression.

Barrett's esophagus surveillance in a prospective Dutch multi-center community-based cohort of 985 patients demonstrates low risk of neoplastic progression.

BACKGROUND AND AIMS: Barrett's esophagus (BE) is accompanied by an increased risk of developing esophageal cancer. Accurate risk-stratification is warranted to improve endoscopic surveillance. Most data available on risk factors is derived from tertiary care centers or from cohorts with limited surveillance time or surveillance quality. The aim of this study was to assess endoscopic and clinical risk factors for progression to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) in a large prospective cohort of BE patients from community hospitals supported by an overarching infrastructure to ensure optimal surveillance quality. METHODS: A well-defined prospective multicenter cohort study was initiated in six community hospitals in the Amsterdam region in 2003. BE patients were identified by PALGA search and included in a prospective surveillance program with a single endoscopist performing all endoscopies at each hospital. Planning and data collection was performed by experienced research nurses who attended all endoscopies. Endpoint was progression to HGD/EAC. RESULTS: Nine hundred eighty-five patients were included for analysis. During median follow-up of 7.9 years (IQR 4.1-12.5) 67 patients were diagnosed with HGD (n = 28) or EAC (n = 39), progression rate 0.78% per patient-year. As a clinical risk factor age at time of endoscopy was associated with neoplastic progression (HR 1.05; 95% CI 1.03-1.08). Maximum Barrett length and low-grade dysplasia (LGD) at baseline were endoscopic predictors of progression (HR 1.15; 95% CI 1.09-1.21 and HR 2.36; 95% CI 1.29-4.33). CONCLUSION: Risk of progression to HGD/EAC in a large, prospective, community-based Barrett's cohort was low. Barrett's length, LGD and age were important risk factors for progression. (www.trialregister.nl NTR1789).

Improved diagnostic stratification of digitised Barrett's oesophagus biopsies by p53 immunohistochemical staining.

AIMS: Interobserver agreement for dysplasia in Barrett's oesophagus (BO) is low, and guidelines advise expert review of dysplastic cases. The aim of this study was to assess the added value of p53 immunohistochemistry (IHC) for the homogeneity within a group of dedicated gastrointestinal (GI) pathologists. METHODS AND RESULTS: Sixty-single haematoxylin and eosin (HE) slide referral BO cases [20 low-grade dysplasia (LGD); 20 high-grade dysplasia (HGD); and 20 non-dysplastic BO reference cases] were digitalised and independently assessed twice in random order by 10 dedicated GI pathologists. After a 'wash-out' period, cases were reassessed with the addition of a corresponding p53 IHC slide. Outcomes were: (i) proportion of 'indefinite for dysplasia' (IND) diagnoses; (ii) interobserver agreement; and (iii) diagnostic accuracy as compared with a consensus 'gold standard' diagnosis defined at an earlier stage by five core expert BO pathologists after their assessment of this case set. Addition of p53 IHC decreased the mean proportion of IND diagnoses from 10 of 60 to eight of 60 (P = 0.071). Mean interobserver agreement increased significantly from 0.45 to 0.57 (P = 0.0021). The mean diagnostic accuracy increased significantly from 72% to 82% (P = 0.0072) after p53 IHC addition. CONCLUSION: Addition of p53 IHC significantly improves the histological assessment of BO biopsies, even within a group of dedicated GI pathologists. It decreases the proportion of IND diagnoses, and increases interobserver agreement and diagnostic accuracy. This justifies the use of accessory p53 IHC within our upcoming national digital review panel for BO biopsy cases.

Patients With Barrett's Esophagus and Confirmed Persistent Low-Grade Dysplasia Are at Increased Risk for Progression to Neoplasia.

BACKGROUND & AIMS: For patients with Barrett's esophagus, the diagnosis of low-grade dysplasia (LGD) is subjective, and reported outcomes vary. We analyzed data from a multicenter study of endoscopic therapy to identify factors associated with progression to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) in patients with LGD of the esophagus. METHODS: We performed a retrospective analysis of data from 255 patients with a primary diagnosis of LGD (78% men; mean age, 63 years) who participated in a randomized controlled trial of surveillance vs radiofrequency ablation in Europe. Three expert pathologists independently reviewed baseline and subsequent LGD specimens. The presence and degree of dysplasia was separately recorded for each biopsy and classified according to the Vienna Classification system. The primary end point was development of HGD or EAC. We performed univariate logistic regression analyses to assess the association between outcomes and factors such as number of pathologists confirming LGD, multifocality of LGD, and persistence of LGD over time. RESULTS: Of the 255 patients, 45 (18%) developed HGD or EAC during a median 42-month follow-up period (interquartile range, 25-61 months); patients were examined by a median 4 endoscopies (interquartile range, 3-6 endoscopies). The number of pathologists confirming LGD was strongly associated with progression to neoplasia; risk for progression increased greatly when all 3 pathologists agreed on LGD (odds ratio, 47.14; 95% confidence interval, 13.10-169.70). When LGD was detected at baseline and confirmed by a subsequent endoscopy, the odds for progression to neoplasia also increased greatly (odds ratio, 9.28; 95% confidence interval, 4.39-19.64). Multifocal LGD was not significantly associated with progression to neoplasia. CONCLUSIONS: The number of pathologists confirming LGD and persistence of LGD over time increase risk for development of HGD or EAC in patients with Barrett's esophagus and LGD. These simple, readily available variables can help stratify risk and select patients for prophylactic ablation therapy.

A Tissue Systems Pathology Test Detects Abnormalities Associated with Prevalent High-Grade Dysplasia and Esophageal Cancer in Barrett's Esophagus.

BACKGROUND: There is a need for improved tools to detect high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) in patients with Barrett's esophagus. In previous work, we demonstrated that a 3-tier classifier predicted risk of incident progression in Barrett's esophagus. Our aim was to determine whether this risk classifier could detect a field effect in nondysplastic (ND), indefinite for dysplasia (IND), or low-grade dysplasia (LGD) biopsies from Barrett's esophagus patients with prevalent HGD/EAC. METHODS: We performed a multi-institutional case-control study to evaluate a previously developed risk classifier that is based upon quantitative image features derived from 9 biomarkers and morphology, and predicts risk for HGD/EAC in Barrett's esophagus patients. The risk classifier was evaluated in ND, IND, and LGD biopsies from Barrett's esophagus patients diagnosed with HGD/EAC on repeat endoscopy (prevalent cases, n = 30, median time to HGD/EAC diagnosis 140.5 days) and nonprogressors (controls, n = 145, median HGD/EAC-free surveillance time 2,015 days). RESULTS: The risk classifier stratified prevalent cases and non-progressor patients into low-, intermediate-, and high-risk classes [OR, 46.0; 95% confidence interval, 14.86-169 (high-risk vs. low-risk); P < 0.0001]. The classifier also provided independent prognostic information that outperformed the subspecialist and generalist diagnosis. CONCLUSIONS: A tissue systems pathology test better predicts prevalent HGD/EAC in Barrett's esophagus patients than pathologic variables. The results indicate that molecular and cellular changes associated with malignant transformation in Barrett's esophagus may be detectable as a field effect using the test. IMPACT: A tissue systems pathology test may provide an objective method to facilitate earlier identification of Barrett's esophagus patients requiring therapeutic intervention. Cancer Epidemiol Biomarkers Prev; 26(2); 240-8. ©2016 AACR.

A Tissue Systems Pathology Assay for High-Risk Barrett's Esophagus.

BACKGROUND: Better methods are needed to predict risk of progression for Barrett's esophagus. We aimed to determine whether a tissue systems pathology approach could predict progression in patients with nondysplastic Barrett's esophagus, indefinite for dysplasia, or low-grade dysplasia. METHODS: We performed a nested case-control study to develop and validate a test that predicts progression of Barrett's esophagus to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC), based upon quantification of epithelial and stromal variables in baseline biopsies. Data were collected from Barrett's esophagus patients at four institutions. Patients who progressed to HGD or EAC in ≥1 year (n = 79) were matched with patients who did not progress (n = 287). Biopsies were assigned randomly to training or validation sets. Immunofluorescence analyses were performed for 14 biomarkers and quantitative biomarker and morphometric features were analyzed. Prognostic features were selected in the training set and combined into classifiers. The top-performing classifier was assessed in the validation set. RESULTS: A 3-tier, 15-feature classifier was selected in the training set and tested in the validation set. The classifier stratified patients into low-, intermediate-, and high-risk classes [HR, 9.42; 95% confidence interval, 4.6-19.24 (high-risk vs. low-risk); P < 0.0001]. It also provided independent prognostic information that outperformed predictions based on pathology analysis, segment length, age, sex, or p53 overexpression. CONCLUSION: We developed a tissue systems pathology test that better predicts risk of progression in Barrett's esophagus than clinicopathologic variables. IMPACT: The test has the potential to improve upon histologic analysis as an objective method to risk stratify Barrett's esophagus patients. Cancer Epidemiol Biomarkers Prev; 25(6); 958-68. ©2016 AACR.

Spatial predisposition of dysplasia in Barrett's esophagus segments: a pooled analysis of the SURF and AIM dysplasia trials.

OBJECTIVES: Surveillance endoscopy detects dysplasia within Barrett's esophagus (BE) and dictates treatment. Current biopsy regimens recommend uniformly spaced random biopsies. We assessed the distribution of dysplasia in BE to develop evidence-based biopsy regimens. METHODS: We performed analysis of the distribution of dysplasia within BE using pretreatment biopsy data from two randomized controlled trials (RCTs) of radiofrequency ablation for dysplastic BE: the SURF (Surveillance vs. Radiofrequency Ablation) trial and the AIM Dysplasia (Ablation of Intestinal Metaplasia (AIM) Containing Dysplasia) trial. We used generalized linear models with generalized estimating equations (GEE) to estimate prevalence differences for dysplasia depending on the standardized location of biopsies. We performed Monte Carlo simulation of biopsy regimens to estimate their yield for any dysplasia within segments. RESULTS: Dysplasia preferentially resides in the proximal-most half of the BE segment that is almost twice as likely to demonstrate dysplasia as the distal-most quartile. In pooled analysis, compared with the distal-most quarter, the prevalence difference in the proximal-most quarter was 22.6%, in the second proximal-most quarter 23.1%, and in the second distal-most quarter 15.3%. The best performing biopsy regimen in simulation studies acquired 8 biopsies in the most proximal cm of BE, 8 biopsies in the second cm, and 2 biopsies in each cm thereafter (q1cm: 8, 8, 2, 2…). A slightly simpler q2cm (every 2 cm) regimen (q2cm: 12, 12, 4…) was nearly as effective. CONCLUSIONS: The post hoc analysis of two RCTs reveals a substantially increased prevalence of dysplasia proximally in BE segments. Our simulations suggest an altered biopsy regimen could increase sensitivity of biopsies in short-segment BE by >30%.

The Presence of Genetic Mutations at Key Loci Predicts Progression to Esophageal Adenocarcinoma in Barrett's Esophagus.

OBJECTIVES: Risk stratification in Barrett's esophagus (BE) is challenging. We evaluated the ability of a panel of genetic markers to predict progression to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC). METHODS: In this case-control study, we assessed a measure of genetic instability, the mutational load (ML), in predicting progression to HGD or EAC. Cases had nondysplastic BE or low-grade dysplasia (LGD) at baseline and developed HGD/EAC ≥1 year later. Controls were matched 2:1, had nondysplastic BE or LGD, and no progression at follow-up. Formalin-fixed, paraffin-embedded tissue was microdissected for the epithelium. Loss of heterozygosity (LOH) and microsatellite instability (MSI) were assessed. ML was calculated from derangements in 10 genomic loci. High-clonality LOH mutations were assigned a value of 1, low-clonality mutations were assigned a value of 0.5, and MSI 0.75 at the first loci, and 0.5 for additional loci. These values were summed to the ML. Receiver operator characteristic (ROC) curves were created. RESULTS: There were 69 patients (46 controls and 23 cases). Groups were similar in age, follow-up time, baseline histology, and the number of microdissected targets. Mean ML in pre-progression biopsies was higher in cases (2.21) than in controls (0.42; P<0.0001). Sensitivity was 100% at ML ≥0.5 and specificity was 96% at ML ≥1.5. Accuracy was highest at 89.9% for ML ≥1. ROC curves for ML ≥1 demonstrated an area under the curve (AUC) of 0.95. CONCLUSIONS: ML in pre-progression BE tissue predicts progression to HGD or EAC. Although further validation is necessary, ML may have utility as a biomarker in endoscopic surveillance of BE.

Barrett's oesophagus patients with low-grade dysplasia can be accurately risk-stratified after histological review by an expert pathology panel.

OBJECTIVE: Reported malignant progression rates for low-grade dysplasia (LGD) in Barrett's oesophagus (BO) vary widely. Expert histological review of LGD is advised, but limited data are available on its clinical value. This retrospective cohort study aimed to determine the value of an expert pathology panel organised in the Dutch Barrett's Advisory Committee (BAC) by investigating the incidence rates of high-grade dysplasia (HGD) and oesophageal adenocarcinoma (OAC) after expert histological review of LGD. DESIGN: We included all BO cases referred to the BAC for histological review of LGD diagnosed between 2000 and 2011. The diagnosis of the expert panel was related to the histological outcome during endoscopic follow-up. Primary endpoint was development of HGD or OAC. RESULTS: 293 LGD patients (76% men; mean 63 years±11.9) were included. Following histological review, 73% was downstaged to non-dysplastic BO (NDBO) or indefinite for dysplasia (IND). In 27% the initial LGD diagnosis was confirmed. Endoscopic follow-up was performed in 264 patients (90%) with a median follow-up of 39 months (IQR 16-72). For confirmed LGD, the risk of HGD/OAC was 9.1% per patient-year. Patients downstaged to NDBO or IND had a malignant progression risk of 0.6% and 0.9% per patient-year, respectively. CONCLUSIONS: Confirmed LGD in BO has a markedly increased risk of malignant progression. However, the vast majority of patients with community LGD will be downstaged after expert review and have a low progression risk. Therefore, all BO patients with LGD should undergo expert histological review of the diagnosis for adequate risk stratification.

Is endoscopic resection an alternative to surgery for early low-risk submucosal gastric cancers: analysis of a large surgical database.

BACKGROUND: Although endoscopic resection (ER) for early gastric cancers (EGCs) has become popular with the development of endoscopic instruments and skillful endoscopists, the risk of lymph node metastasis (LNM) is still an obstacle in performing ER. In this study, we aimed to identify the risk factors of LNM and validated the expanded criteria, with the goal of suggesting modified criteria for ER in submucosal EGCs. METHODS: Of patients who underwent gastrectomy with LN dissection and were diagnosed as EGCs with depth of invasion such as sm1, sm2 or ≤ 500 µm from 1999 to 2008, 318 EGCs with submucosal invasion ≤ 500 µm were enrolled through pathologic evaluations. To identify the risk factors of LNM, a multivariate analysis of clinicopathologic factors was performed. By combining the independent risk factors of LNM, the risk of LNM was analyzed. RESULT: LNM were detected in 35 cases (11.0 %). Tumors >30 mm in size and with lymphatic invasion were identified as an independent risk factor for LNM in EGCs with depth of invasion ≤ 500 µm. Among 94 cases meeting the expanded criteria, two cases (2.1 %) were found to have LNM. Based on the submucosal invasion <300 µm, there was no LNM in EGCs with a size ≤ 30 mm and no lymphovascular invasion, regardless of differentiation grade. CONCLUSION: To exclude the possibility of LNM, applying the modified criteria based on the submucosal invasion <300 µm in performing ER might be worthwhile.