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.

Covered transjugular intrahepatic portosystemic shunt versus endoscopic therapy + ß-blocker for prevention of variceal rebleeding.

UNLABELLED: Gastroesophageal variceal bleeding in patients with cirrhosis is associated with significant morbidity and mortality, as well as a high rebleeding risk. Limited data are available on the role of transjugular intrahepatic portosystemic shunt (TIPS) with covered stents in patients receiving standard endoscopic, vasoactive, and antibiotic treatment. In this multicenter randomized trial, long-term endoscopic variceal ligation (EVL) or glue injection + ß-blocker treatment was compared with TIPS placement in 72 patients with a first or second episode of gastric and/or esophageal variceal bleeding, after hemodynamic stabilization upon endoscopic, vasoactive, and antibiotic treatment. Randomization was stratified according to Child-Pugh score. Kaplan-Meier (event-free) survival estimates were used for the endpoints rebleeding, death, treatment failure, and hepatic encephalopathy. During a median follow-up of 23 months, 10 (29%) of 35 patients in the endoscopy + ß-blocker group, as compared to 0 of 37 (0%) patients in the TIPS group, developed variceal rebleeding (P = 0.001). Mortality (TIPS 32% vs. endoscopy 26%; P = 0.418) and treatment failure (TIPS 38% vs. endoscopy 34%; P = 0.685) did not differ between groups. Early hepatic encephalopathy (within 1 year) was significantly more frequent in the TIPS group (35% vs. 14%; P = 0.035), but during long-term follow-up this difference diminished (38% vs. 23%; P = 0.121). CONCLUSIONS: In unselected patients with cirrhosis, who underwent successful endoscopic hemostasis for variceal bleeding, covered TIPS was superior to EVL + ß-blocker for reduction of variceal rebleeding, but did not improve survival. TIPS was associated with higher rates of early hepatic encephalopathy.

Derivation of genetic biomarkers for cancer risk stratification in Barrett's oesophagus: a prospective cohort study.

OBJECTIVE: The risk of developing adenocarcinoma in non-dysplastic Barrett's oesophagus is low and difficult to predict. Accurate tools for risk stratification are needed to increase the efficiency of surveillance. We aimed to develop a prediction model for progression using clinical variables and genetic markers. METHODS: In a prospective cohort of patients with non-dysplastic Barrett's oesophagus, we evaluated six molecular markers: p16, p53, Her-2/neu, 20q, MYC and aneusomy by DNA fluorescence in situ hybridisation on brush cytology specimens. Primary study outcomes were the development of high-grade dysplasia or oesophageal adenocarcinoma. The most predictive clinical variables and markers were determined using Cox proportional-hazards models, receiver operating characteristic curves and a leave-one-out analysis. RESULTS: A total of 428 patients participated (345 men; median age 60 years) with a cumulative follow-up of 2019 patient-years (median 45 months per patient). Of these patients, 22 progressed; nine developed high-grade dysplasia and 13 oesophageal adenocarcinoma. The clinical variables, age and circumferential Barrett's length, and the markers, p16 loss, MYC gain and aneusomy, were significantly associated with progression on univariate analysis. We defined an 'Abnormal Marker Count' that counted abnormalities in p16, MYC and aneusomy, which significantly improved risk prediction beyond using just age and Barrett's length. In multivariate analysis, these three factors identified a high-risk group with an 8.7-fold (95% CI 2.6 to 29.8) increased HR when compared with the low-risk group, with an area under the curve of 0.76 (95% CI 0.66 to 0.86). CONCLUSIONS: A prediction model based on age, Barrett's length and the markers p16, MYC and aneusomy determines progression risk in non-dysplastic Barrett's oesophagus.

Prospective cross-sectional study on faecal immunochemical tests: sex specific cut-off values to obtain equal sensitivity for colorectal cancer?

BACKGROUND: Faecal immunochemical tests (FITs) are commonly used in colorectal cancer (CRC) screening. Diagnostic accuracy of FIT differs between males and females. This so far unexplained difference could result in a dissimilarity in screening outcome between both sexes. The aim of this study is to compare sensitivity and specificity of a FIT between males and females, and study potential explanatory variables. METHODS: In this cross-sectional study, data were prospectively collected. 3,022 subjects performed a FIT prior to complete colonoscopy. Sensitivity, specificity, and ROC curves were compared for both sexes. Potential explanatory variables of the relation between sensitivity and sex were explored. RESULTS: At all cut-off values, FIT sensitivity for CRC was higher (range 13-23%) and specificity was lower (range 2-4%) in males compared to females. At 75 ng/ml, sensitivity for CRC was 93% in males compared to 71% in females (p = 0.03), and specificity was 90% in males compared to 93% in females (p = <0.05). For advanced adenomas, males had a slightly higher sensitivity and lower specificity (not significant). At 75 ng/ml, sensitivity for advanced adenomas was 33% in males compared to 29% in females (p = 0.46), and specificity was 93% in males compared to 95% in females (p = 0.22). ROC curves were similar for both sexes, and equal combinations of sensitivity and specificity could be achieved by adjusting the cut-off values. For CRC, the difference in sensitivity could not be explained by age or location of the tumour. CONCLUSIONS: FIT has a higher sensitivity and a lower specificity for CRC in males than in females. Equal test characteristics can be achieved by allowing separate cut-off values for both sexes. Location and age do not explain the observed differences in sensitivity.

Validation of the Prague C&M classification of Barrett's esophagus in clinical practice.

BACKGROUND AND STUDY AIMS: The Prague C&M classification for Barrett's esophagus has found widespread acceptance but has only been validated by Barrett's experts scoring video sequences. To date, validation has been lacking for its application in routine practice during real-time endoscopy. The aim of this study was to evaluate agreement between Barrett's experts and community hospital endoscopists when using this classification to describe Barrett's esophagus and hiatal hernia length during real-time endoscopy. PATIENTS AND METHODS: Patients underwent two consecutive endoscopies performed by different endoscopists. The study was performed in two cohorts: one cohort was seen by Barrett's experts and the other cohort by community hospital endoscopists. Landmarks were recorded according to the Prague classification. Outcomes were interobserver agreement (assessed with intraclass correlation coefficient [ICC]), absolute agreement, and relative agreement. RESULTS: A total of 187 patients were included, with median extent of C3M5 (IQR C1 - 7 M4 - 9) for Barrett's esophagus and 3 cm (IQR 2-5) for hiatal hernia length. ICC was 0.91 (95 % confidence interval [CI] 0.88-0.93) for maximum length, 0.92 (95% CI 0.90-0.94) for circumferential extent, and 0.59 (95% CI 0.49-0.68) for hiatal hernia length. Absolute agreement within ≤ 1 cm was 74% (95% CI 68-80) for circumference, 68% (95% CI 62-75) for length, and 63% (95% CI 56 - 70) for hiatal hernia length. Relative agreement was 91% for Barrett's esophagus and 80 % for hiatal hernia length. Barrett's experts and community hospital endoscopists showed no differences in agreement. Shorter Barrett's segments (≤ 5 cm) had lower agreement compared with longer segments (> 5 cm). CONCLUSIONS: Agreement was good for Barrett's esophagus and reasonable for hiatal hernia length. These findings strengthen the value of the Prague C&M classification to describe Barrett's esophagus and hiatal hernia length. Although absolute agreement during real-time endoscopy was high, one should anticipate that Barrett's values may vary by 1 - 2 cm between two endoscopies.

Endoscopic trimodal imaging detects colonic neoplasia as well as standard video endoscopy.

BACKGROUND & AIMS: Endoscopic trimodal imaging (ETMI) is a novel endoscopic technique that combines high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) that has only been studied in academic settings. We performed a randomized, controlled trial in a nonacademic setting to compare ETMI with standard video endoscopy (SVE) in the detection and differentiation of colorectal lesions. METHODS: The study included 234 patients scheduled to receive colonoscopy who were randomly assigned to undergo a colonoscopy in tandem with either ETMI or SVE. In the ETMI group (n=118), first examination was performed using HRE, followed by AFI. In the other group, both examinations were performed using SVE (n=116). In the ETMI group, detected lesions were differentiated using AFI and NBI. RESULTS: In the ETMI group, 87 adenomas were detected in the first examination (with HRE), and then 34 adenomas were detected during second inspection (with AFI). In the SVE group, 79 adenomas were detected during the first inspection, and then 33 adenomas were detected during the second inspection. Adenoma detection rates did not differ significantly between the 2 groups (ETMI: 1.03 vs SVE: 0.97, P=.360). The adenoma miss-rate was 29% for HRE and 28% for SVE. The sensitivity, specificity, and accuracy of NBI in differentiating adenomas from nonadenomatous lesions were 87%, 63%, and 75%, respectively; corresponding values for AFI were 90%, 37%, and 62%, respectively. CONCLUSIONS: In a nonacademic setting, ETMI did not improve the detection rate for adenomas compared with SVE. NBI and AFI each differentiated colonic lesions with high levels of sensitivity but low levels of specificity.

Hemorrhoids detected at colonoscopy: an infrequent cause of false-positive fecal immunochemical test results.

BACKGROUND: Colorectal cancer screening by fecal immunochemical tests (FITs) is hampered by frequent false-positive (FP) results and thereby the risk of complications and strain on colonoscopy capacity. Hemorrhoids might be a plausible cause of FP results. OBJECTIVE: To determine the contribution of hemorrhoids to the frequency of FP FIT results. DESIGN: Retrospective analysis from prospective cohort study. SETTING: Five large teaching hospitals, including 1 academic hospital. PATIENTS: All subjects scheduled for elective colonoscopy. INTERVENTIONS: FIT before bowel preparation. MAIN OUTCOME MEASUREMENTS: Frequency of FP FIT results in subjects with hemorrhoids as the only relevant abnormality compared with FP FIT results in subjects with no relevant abnormalities. Logistic regression analysis to determine colonic abnormalities influencing FP results. RESULTS: In 2855 patients, 434 had positive FIT results: 213 had advanced neoplasia and 221 had FP results. In 9 individuals (4.1%; 95% CI, 1.4-6.8) with an FP FIT result, hemorrhoids were the only abnormality. In univariate unadjusted analysis, subjects with hemorrhoids as the only abnormality did not have more positive results (9/134; 6.7%) compared with subjects without any abnormalities (43/886; 4.9%; P = .396). Logistic regression identified hemorrhoids, nonadvanced polyps, and a group of miscellaneous abnormalities, all significantly influencing false positivity. Of 1000 subjects with hemorrhoids, 67 would have FP results, of whom 18 would have FP results because of hemorrhoids only. LIMITATIONS: Potential underreporting of hemorrhoids; high-risk individuals. CONCLUSIONS: Hemorrhoids in individuals participating in colorectal cancer screening will probably not lead to a substantial number of false-positive test results.

Faecal immunochemical test accuracy in patients referred for surveillance colonoscopy: a multi-centre cohort study.

BACKGROUND: Given the increasing burden on colonoscopy capacity, it has been suggested that faecal immunochemical test (FIT) results could guide surveillance colonoscopy intervals. Against this background, we have evaluated the test accuracy of single and double FIT sampling to detect colorectal cancer (CRC) and/or advanced adenomas in an asymptomatic colonoscopy-controlled high-risk population. METHODS: Cohort study of asymptomatic high-risk patients (personal history of adenomas/CRC or family history of CRC), who provided one or two FITs before elective colonoscopy. Test accuracy of FIT for detection of CRC and advanced adenomas was determined (cut-off level 50 ng/ml). RESULTS: 1,041 patients provided a FIT (516 personal history of adenomas, 172 personal history of CRC and 353 family history of CRC). Five CRCs (0.5%) and 101 advanced adenomas (9.7%) were detected by colonoscopy. Single FIT sampling resulted in a sensitivity, specificity, PPV and NPV for CRC of 80%, 89%, 3% and 99.9%, respectively, and for advanced adenoma of 28%, 91%, 24% and 92%, respectively. Double FIT sampling did not result in a significantly higher sensitivity for advanced neoplasia. Simulation of multiple screening rounds indicated that sensitivity of FIT for advanced adenoma could reach 81% after 5 screening rounds. CONCLUSIONS: In once-only FIT sampling before surveillance colonoscopy, 70% of advanced neoplasia were missed. A simulation approach indicates that multiple screening rounds may be more promising in detecting advanced neoplasia and could potentially alleviate endoscopic burden.

Endoscopic trimodal imaging versus standard video endoscopy for detection of early Barrett's neoplasia: a multicenter, randomized, crossover study in general practice.

BACKGROUND: Endoscopic trimodal imaging (ETMI) may improve detection of early neoplasia in Barrett's esophagus (BE). Studies with ETMI so far have been performed in tertiary referral settings only. OBJECTIVE: To compare ETMI with standard video endoscopy (SVE) for the detection of neoplasia in BE patients with an intermediate-risk profile. DESIGN: Multicenter, randomized, crossover study. SETTING: Community practice. PATIENTS AND METHODS: BE patients with confirmed low-grade intraepithelial neoplasia (LGIN) underwent both ETMI and SVE in random order (interval 6-16 weeks). During ETMI, BE was inspected with high-resolution endoscopy followed by autofluorescence imaging (AFI). All visible lesions were then inspected with narrow-band imaging. During ETMI and SVE, visible lesions were sampled followed by 4-quadrant random biopsies every 2 cm. MAIN OUTCOME MEASUREMENTS: Overall histological yield of ETMI and SVE and targeted histological yield of ETMI and SVE. RESULTS: A total of 99 patients (79 men, 63±10 years) underwent both procedures. ETMI had a significantly higher targeted histological yield because of additional detection of 22 lesions with LGIN/high-grade intraepithelial neoplasia (HGIN)/carcinoma (Ca) by AFI. There was no significant difference in the overall histological yield (targeted+random) between ETMI and SVE. HGIN/Ca was diagnosed only by random biopsies in 6 of 24 patients and 7 of 24 patients, with ETMI and SVE, respectively. LIMITATIONS: Inspection, with high-resolution endoscopy and AFI, was performed sequentially. CONCLUSION: ETMI performed in a community-based setting did not improve the overall detection of dysplasia compared with SVE. The diagnosis of dysplasia is still being made in a significant number of patients by random biopsies. Patients with a confirmed diagnosis of LGIN have a significant risk of HGIN/Ca. ( CLINICAL TRIAL REGISTRATION NUMBER: ISRCTN91816824; NTR867.).

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).

Low-grade dysplasia in Barrett's esophagus: overdiagnosed and underestimated.

OBJECTIVES: Published data on the natural history of low-grade dysplasia (LGD) in Barrett's esophagus (BE) are inconsistent and difficult to interpret. We investigated the natural history of LGD in a large community-based cohort of BE patients after reviewing the original histological diagnosis by an expert panel of pathologists. METHODS: Histopathology reports of all patients diagnosed with LGD between 2000 and 2006 in six non-university hospitals were reviewed by two expert pathologists. This panel diagnosis was subsequently compared with the histological outcome during prospective endoscopic follow-up. RESULTS: A diagnosis of LGD was made in 147 patients. After pathology review, 85% of the patients were downstaged to non-dysplastic BE (NDBE) or to indefinite for dysplasia. In only 15% of the patients was the initial diagnosis LGD. Endoscopic follow-up was carried out in 83.6% of patients, with a mean follow-up of 51.1 months. For patients with a consensus diagnosis of LGD, the cumulative risk of progressing to high-grade dysplasia or carcinoma (HGD or Ca) was 85.0% in 109.1 months compared with 4.6% in 107.4 months for patients downstaged to NDBE (P<0.0001). The incidence rate of HGD or Ca was 13.4% per patient per year for patients in whom the diagnosis of LGD was confirmed. For patients downstaged to NDBE, the corresponding incidence rate was 0.49%. CONCLUSIONS: LGD in BE is an overdiagnosed and yet underestimated entity in general practice. Patients diagnosed with LGD should undergo an expert pathology review to purify this group. In case the diagnosis of LGD is confirmed, patients should undergo strict endoscopic follow-up or should be considered for endoscopic ablation therapy.

Chromoendoscopy and narrow-band imaging compared with high-resolution magnification endoscopy in Barrett's esophagus.

BACKGROUND & AIMS: The aim of this study was to compare magnified still images obtained with high-resolution white light endoscopy, indigo carmine chromoendoscopy, acetic acid chromoendoscopy, and narrow-band imaging to determine the best technique for use in Barrett's esophagus. METHODS: We obtained magnified images from 22 areas with the 4 aforementioned techniques. Seven endoscopists with no specific expertise in Barrett's esophagus or advanced imaging techniques and 5 international experts in this field evaluated these 22 areas for overall image quality, mucosal image quality, and vascular image quality. In addition, the regularity of mucosal and vascular patterns and the presence of abnormal blood vessels were evaluated, and this was correlated with histology. RESULTS: The interobserver agreement for the 3 features of mucosal morphology with white light images ranged from kappa = 0.51 (95% confidence interval [CI]: 0.46-0.55) to kappa = 0.53 (95% CI: 0.50-0.57) for all observers, from kappa = 0.43 (95% CI: 0.33-0.54) to kappa = 0.53 (95% CI: 0.41-0.64) for experts, and from kappa = 0.51 (95% CI: 0.15-0.33) to kappa = 0.64 (95% CI: 0.58-0.70) for nonexperts. The interobserver agreement in these groups did not improve by adding one of the enhancement techniques. The yield for identifying early neoplasia with white light images was 86% for all observers, 90% for experts, and 84% for nonexperts. The addition of enhancement techniques did not improve the yield neoplasia. CONCLUSIONS: The addition of indigo carmine chromoendoscopy, acetic acid chromoendoscopy, or narrow-band imaging to white light images did not improve interobserver agreement or yield identifying early neoplasia in Barrett's esophagus.

Combining autofluorescence imaging and narrow-band imaging for the differentiation of adenomas from non-neoplastic colonic polyps among experienced and non-experienced endoscopists.

OBJECTIVES: Endoscopic tri-modal imaging incorporates high-resolution white-light endoscopy (HR-WLE), narrow-band imaging (NBI), and autofluorescence imaging (AFI). Combining these advanced techniques may improve endoscopic differentiation between adenomas and non-neoplastic polyps. In this study, we aimed to assess the interobserver variability and accuracy of HR-WLE, NBI, and AFI for polyp differentiation and to evaluate the combined use of AFI and NBI. METHODS: First, still images of 50 polyps (22 adenomas; median 3 mm) were randomly displayed to three experienced and four non-experienced endoscopists. All HR-WLE and NBI images were scored for Kudo classification and AFI images for color. Second, the combined AFI and NBI images were assessed using a newly developed algorithm by six additional non-experienced endoscopists. RESULTS: The outcomes measured were interobserver agreement and diagnostic accuracy using histopathology as reference standard. Experienced endoscopists had better interobserver agreement for NBI (kappa=0.77) than for AFI (kappa=0.33), whereas non-experienced endoscopists had better agreement for AFI (kappa=0.58) than for NBI (kappa=0.33). The accuracies of HR-WLE, NBI, and AFI among experienced endoscopists were 65, 70, and 74, respectively. Figures among non-experienced endoscopists were 57, 63, and 77. The algorithm was associated with a significantly higher accuracy of 85% among all observers (P<0.023). These figures were confirmed in the second evaluation study. CONCLUSIONS: Non-experienced endoscopists have better interobserver agreement and accuracy for AFI than for HR-WLE or NBI, indicating that AFI is easier to use for polyp differentiation in non-experienced setting. The newly developed algorithm, combining information of AFI and NBI together, had the highest accuracy and obtained equal results between experienced and non-experienced endoscopists.

Colonic stenting as bridge to surgery versus emergency surgery for management of acute left-sided malignant colonic obstruction: a multicenter randomized trial (Stent-in 2 study).

BACKGROUND: Acute left-sided colonic obstruction is most often caused by malignancy and the surgical treatment is associated with a high mortality and morbidity rate. Moreover, these operated patients end up with a temporary or permanent stoma. Initial insertion of an enteral stent to decompress the obstructed colon, allowing for surgery to be performed electively, is gaining popularity. In uncontrolled studies stent placement before elective surgery has been suggested to decrease mortality, morbidity and number of colostomies. However stent perforation can lead to peritoneal tumor spill, changing a potentially curable disease in an incurable one. Therefore it is of paramount importance to compare the outcomes of colonic stenting followed by elective surgery with emergency surgery for the management of acute left-sided malignant colonic obstruction in a randomized multicenter fashion. METHODS/DESIGN: Patients with acute left-sided malignant colonic obstruction eligible for this study will be randomized to either emergency surgery (current standard treatment) or colonic stenting as bridge to elective surgery. Outcome measurements are effectiveness and costs of both strategies. Effectiveness will be evaluated in terms of quality of life, morbidity and mortality. Quality of life will be measured with standardized questionnaires (EORTC QLQ-C30, EORTC QLQ-CR38, EQ-5D and EQ-VAS). Morbidity is defined as every event leading to hospital admission or prolonging hospital stay. Mortality will be analyzed as total mortality as well as procedure-related mortality. The total costs of treatment will be evaluated by counting volumes and calculating unit prices. Including 120 patients on a 1:1 basis will have 80% power to detect an effect size of 0.5 on the EORTC QLQ-C30 global health scale, using a two group t-test with a 0.05 two-sided significance level. Differences in quality of life and morbidity will be analyzed using mixed-models repeated measures analysis of variance. Mortality will be compared using Kaplan-Meier curves and log-rank statistics. DISCUSSION: The Stent-in 2 study is a randomized controlled multicenter trial that will provide evidence whether or not colonic stenting as bridge to surgery is to be performed in patients with acute left-sided colonic obstruction. TRIAL REGISTRATION: Current Controlled Trials ISRCTN46462267.

Systematic review of ventricular peritoneal shunt and percutaneous endoscopic gastrostomy: a safe combination.

OBJECTIVE Various international and national gastrointestinal guidelines take different positions on whether ventriculoperitoneal shunt (VPS) insertion is a contraindication to percutaneous endoscopic gastrostomy (PEG). The objective of this meta-analysis was to try to answer the question of whether VPS insertion is a contraindication to PEG. METHODS A systematic review of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Electronic databases PubMed and Embase were searched using variations of the terms "ventriculo-peritoneal shunt" and "percutaneous (endoscopic) gastrostomy." This search resulted in 70 studies, 9 of which were relevant. These were cross-referenced, and 1 additional study was found, resulting in 10 studies in this systematic review. RESULTS The 10 relevant studies in adult cohorts included 208 patients. All studies save one were retrospective and, in general, poor quality. Among the studies with relevant data, there were 26 (12.5% of 208 cases) VPS infections and 4 (4.4% of 90 cases) VPSs that malfunctioned. In 137 patients the VPS had been placed before the PEG tube, with a VPS infection rate of 4.4%. More VPS infections occurred among the 55 patients who first had a PEG and a subsequent VPS (21.8%) and in the 16 patients who had simultaneous PEG tube and VPS placement (50%). The heterogeneity of the studies in this analysis prohibited statistical comparisons of the timing of VPS and PEG tube placement. CONCLUSIONS This systematic review indicated that VPS placement in combination with a PEG has a high but acceptable VPS complication rate. Therefore, VPS insertion should not be considered a contraindication to the placement of a PEG tube. Preferably, a PEG tube should be placed after the VPS. Waiting 7-10 days between VPS insertion and a PEG seems reasonable, but this could not be corroborated in this review.

Long-term risk of oesophagitis, Barrett's oesophagus and oesophageal cancer in achalasia patients.

Achalasia is a motility disorder of the oesophagus of unknown origin in which loss of relaxation of the lower oesophageal sphincter (LOS) and aperistalsis in the distal oesophagus leads to functional oesophageal obstruction. The treatment is symptomatic, aimed at lowering of the LOS pressure, and may be accompanied by various side effects, including gastro-oesophageal reflux, a risk factor for oesophagitis and its complications. Stasis and fermentation can also lead to inflammation of the oesophageal mucosa, giving rise to hyperplasia of the epithelium, multifocal dysplasia and in some patients eventually squamous cell carcinoma. Unfortunately, the sensitivity and specificity of endoscopical inspection to assess inflammation or dysplasia of the oesophageal lining is low, such that biopsy sampling is necessary for accurate assessment. Although it is generally accepted that achalasia is a pre-malignant disorder, the reported increased risk of patients with achalasia developing a squamous cell carcinoma varies from 0 to 140 times that of the normal population. In addition, achalasia may predispose to Barrett's metaplasia and oesophageal adenocarcinoma, which have been described in case reports after myotomy. Surveillance endoscopy with tissue sampling to detect pre-neoplastic lesions has been recommended, even though this can be very difficult due to mucosal adherence of food as well as hyperplastic changes of the mucosa. In the event of moderate to severe inflammation and/or persisting stasis of food despite adequate LOS pressure-lowering therapy, the surveillance interval should be shortened and performed after a 3-day liquid diet. The exact technique and time intervals still need to be established, however.

Dynamic clonal equilibrium and predetermined cancer risk in Barrett's oesophagus.

Surveillance of Barrett's oesophagus allows us to study the evolutionary dynamics of a human neoplasm over time. Here we use multicolour fluorescence in situ hybridization on brush cytology specimens, from two time points with a median interval of 37 months in 195 non-dysplastic Barrett's patients, and a third time point in a subset of 90 patients at a median interval of 36 months, to study clonal evolution at single-cell resolution. Baseline genetic diversity predicts progression and remains in a stable dynamic equilibrium over time. Clonal expansions are rare, being detected once every 36.8 patient years, and growing at an average rate of 1.58 cm(2) (95% CI: 0.09-4.06) per year, often involving the p16 locus. This suggests a lack of strong clonal selection in Barrett's and that the malignant potential of 'benign' Barrett's lesions is predetermined, with important implications for surveillance programs.

Is esophagogastroduodenoscopy before Roux-en-Y gastric bypass or sleeve gastrectomy mandatory?

BACKGROUND: Roux-Y Gastric Bypass is a frequently used technique in bariatric surgery. Postoperative anatomy is altered by exclusion of the stomach, which makes this organ inaccessible for future esophagogastroduodenoscopy (EGD). The value of preoperative assessment of the stomach is unclear. Some institutions choose to investigate the future remnant stomach by EGD, others do not. Aim of the present study is to quantify the yield of preoperative EGD in our institution. METHODS: Patients, planned for primary laparoscopic Roux-Y Gastric Bypass (LRYGB) or laparoscopic sleeve gastrectomy from December 2007 until August 2012, were screened by EGD in advance. Results of EGD and patient characteristics were retrospectively analyzed and categorized according to a classification system based on intervention needed. RESULTS: 523 patients (122 male, 401 female, mean age 44.3 years, average BMI 46.6) underwent preoperative EGD. In 257 patients (48.9%) no abnormality was found (group A), 117 patients (17.2%) had abnormalities without treatment consequences (B1), 84 patients (of the 326 tested [comment #1, reviewer #1, 26.8%] were H. Pylori positive (B2), in 75 (14.3%) treatment with proton pump inhibitors was required (B3), 6 (1.1%) required follow up EGD before surgery (C). For1 patient (0.2%) the operation was canceled because preoperative EGD presented with Barrett's esophagus with carcinoma (D). When all abnormalities were taken into account, baselines did show a significant difference for age, gender and reflux symptoms. CONCLUSION: Standard preoperative assessment by EGD in patients who are planned for bariatric surgery is not indicated. The number needed to screen to find clinically significant abnormalities is high.

[Colonic obstruction due to volvulus of the sigmoid colon or caecum]. / Colon-obstructie door volvulus van sigmoïd of caecum.

3 patients, 2 women aged 41 and 47 and one man aged 75 years, presented with abdominal pain and distension. In 2 patients the diagnosis 'sigmoid volvulus' was reached following plain abdominal X-ray. Both patients underwent sigmoidal resection with primary anastomosis after endoscopic deflation. The third patient proved to have a caecal volvulus on emergency laparotomy and underwent ileocaecal resection. In 2/3 of the cases diagnosis can be made by history, physical examination and conventional X-ray. Delay in the diagnosis increases the risk of peritonitis and death due to ischaemia and perforation of the colon. In the absence of peritoneal tenderness, signs of ischaemia or sepsis, the initial treatment consists of endoscopic deflation, which is successful in 68-78% of cases. Resection of the sigmoid colon is recommended a few days after endoscopic decompression in order to prevent recurrence. Caecal volvulus is not suitable for treatment with endoscopic deflation and should be treated with ileocaecal resection.