Evaluation of a novel cryoballoon swipe ablation system in bench, porcine, and human esophagus models.

Current ablation devices for dysplastic Barrett's esophagus are effective but have significant limitations. This pilot study aims to evaluate the safety, feasibility, and dose response of a novel cryoballoon swipe ablation system (CbSAS) in three experimental in vitro and in vivo models. CbSAS is a through-the-scope compliant balloon that is simultaneously inflated and cooled by liquid nitrous oxide delivered from a disposable handheld unit. When the cryogen is applied through a special diffuser it covers a 90° section of the circumference of the esophagus for 3 cm length. Doses range from 0.9 to 0.5 mm/second. (1) Bench model: The fixture consisted of an 'esophagus-like' tube lined with agar at 37°C to create an inner diameter of 20 or 30 mm, within which thermocouples were embedded. (2) In vivo porcine esophagus: CbSAS ablations were performed in animals that were euthanized and histological assessments of depth and percentage of esophageal mucosa successfully ablated were done. (3) In vivo, pre-esophagectomy human esophagus. After CbSAS ablations, histological assessments were performed (at 0, 4, and 28 days) to assess the depth and percentage of ablated mucosa. As outcomes, we assessed the safety and tolerability (pain and serious, device-related adverse events); efficacy (depth and uniformity) of ablation; and device performance (ease of deployment and device malfunction). In the bench model, during CbSAS, thermocouples measured minimal temperatures of -40 to -48 °C at all doses. In the porcine model, maximal effect on the mucosa was reached with a dose of 0.8 mm/second that extended to superficial submucosa, while 0.5 mm/second extended through the submucosa. All animals tolerated the treatments and, regardless of ablation dose, continued oral intake and gained weight. In the human model, six patients (5 male, 1 female, mean age 68) tolerated the procedure without adverse events. CbSAS was simple to operate, and balloon contact with tissue was easily and uniformly maintained. The maximal effect on the mucosa is achieved with a 0.8 mm/second dose. We concluded that the CbSAS device enables uniform 3 cm long, quarter-circumferential mucosal ablation in a one-step process by using a novel, through-the-scope balloon. The CbSAS delivers predictable ablation with mucosal and limited submucosal necrosis in bench, animal, and human esophagus. Because of its ease of use, this new device merits further clinical study in the treatment of patients with dysplastic Barrett's esophagus.

The 2018 ISDE achalasia guidelines.

Achalasia is a relatively rare primary motor esophageal disorder, characterized by absence of relaxations of the lower esophageal sphincter and of peristalsis along the esophageal body. As a result, patients typically present with dysphagia, regurgitation and occasionally chest pain, pulmonary complication and malnutrition. New diagnostic methodologies and therapeutic techniques have been recently added to the armamentarium for treating achalasia. With the aim to offer clinicians and patients an up-to-date framework for making informed decisions on the management of this disease, the International Society for Diseases of the Esophagus Guidelines proposed and endorsed the Esophageal Achalasia Guidelines (I-GOAL). The guidelines were prepared according the Appraisal of Guidelines for Research and Evaluation (AGREE-REX) tool, accredited for guideline production by NICE UK. A systematic literature search was performed and the quality of evidence and the strength of recommendations were graded according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Given the relative rarity of this disease and the paucity of high-level evidence in the literature, this process was integrated with a three-step process of anonymous voting on each statement (DELPHI). Only statements with an approval rate >80% were accepted in the guidelines. Fifty-one experts from 11 countries and 3 representatives from patient support associations participated to the preparations of the guidelines. These guidelines deal specifically with the following achalasia issues: Diagnostic workup, Definition of the disease, Severity of presentation, Medical treatment, Botulinum Toxin injection, Pneumatic dilatation, POEM, Other endoscopic treatments, Laparoscopic myotomy, Definition of recurrence, Follow up and risk of cancer, Management of end stage achalasia, Treatment options for failure, Achalasia in children, Achalasia secondary to Chagas' disease.

Precision GERD management for the 21st century.

The highly heterogeneous nature of gastroesophageal reflux disease (GERD), together with the multiplicity of available diagnostic and therapeutic options (lifestyle, pharmacologic, endoscopic and surgical) available today call for a new approach that funnels the multidimensionality of the disease into precise and effective algorithms - reviewed herein- aimed at improving clinical outcomes.

Whole greater than the parts: integrated esophageal centers (IEC) and advanced training in esophageal diseases.

An integrated esophageal center (IEC) is a multidisciplinary team with expertise, skill, range, and facilities necessary to achieve optimal outcomes in patients with esophageal diseases efficiently and expeditiously. Within IEC, patients presenting with esophageal symptoms undergo a detailed clinical, functional and structural evaluation of their esophagus prior to implementation of tailored medical, endoscopic or surgical therapy. Serving as a core, the IEC clinical practice also supports research and innovation in esophageal diseases as well as public and physician education. Referrals to the unit may be primary, either from primary care or self-initiated, or secondary from other specialty practices, to reassess patients who have previously failed therapies and to manage complex or complicated cases. The fundamental goals of the IEC are to provide value for patients with esophageal diseases, streamlining complex diagnostic investigations and expediting therapies aiming at reducing costs while improving clinical outcomes, and to accelerate knowledge generation through robust interaction and cross-training across disciplines. The organization of the IEC goes beyond traditional academic and clinical silos and involves a director and administrative team coordinating faculty and fellows from both medical and surgical disciplines and supported by other clinical lines, such as radiology, pathology, etc., while it interfaces with physicians, the public, basic, translational and clinical research groups, and related industry partners.

Ineffective esophageal motility: clinical, manometric, and outcome characteristics in patients with and without abnormal esophageal acid exposure.

The etiology and clinical impact of ineffective esophageal motility (IEM) remain poorly understood. Unless gastroesophageal acid reflux (GERD) is identified, symptomatic patients with IEM are challenging to treat. We sought to determine whether any clinical or functional characteristics could distinguish those patients with IEM and either normal or abnormal esophageal acid exposure.In this retrospective cohort study, we identified 46 consecutive patients presenting with heartburn, and other GER symptoms who underwent clinical, endoscopic, and functional evaluation that included high-resolution manometry (HRM) and ambulatory pH monitoring. IEM was defined using the Chicago Classification criteria (v.3) as ≥50% ineffective swallows (DCI ≤ 450 mmHg.s.cm). Esophageal acid exposure by ambulatory pH monitoring was considered abnormal when total time with esophageal pH < 4 exceeded 4.2%.Of the 46 IEM patients identified, 19 (mean age: 42 years, 37% female), had normal esophageal acid exposure and 27 patients, mean age 54 years, 33% female, evidence of pathologic acid reflux. There was a 12 years age difference between the groups, with those with normal acid exposure being significantly younger (P < 0.01); the mean body mass index (BMI) was 22.6 ± 0.6 in the normal group and 25.4 ± 0.7 in the abnormal group (P < 0.001); otherwise the groups were endoscopically and histologically similar. Symptoms were not discriminatory and heartburn and regurgitation were the most prevalent in both groups. HRM did not discriminate symptomatic patients with IEM and either normal or abnormal esophageal acid exposure. Proton pump inhibition (PPI) therapy was significantly more effective (74% vs. 10%) in patients with pathologic acid reflux (P < 0.001). As pH exposure becomes abnormal in the context of IEM, there is dominance for supine reflux.IEM appears to be an early, primary event, eventually associated with pathologic acid exposure, particularly supine. Higher BMI is also associated with abnormal esophageal acid exposure in such patients. GER symptoms are not discriminatory in patients with IEM with and without underlying pathologic acid reflux. Clinical response to PPI in such patients depends on the presence of esophageal pathologic acid exposure. Those with IEM and normal acid exposure remain symptomatic and mostly resistant to therapy.

Clinical and manometric characteristics of patients with Parkinson's disease and esophageal symptoms.

Dysphagia is a common problem in patients with Parkinson's disease (PD); its etiology is multifactorial and its management is challenging. In this retrospective cohort analysis using prospectively collected data, we aimed to objectively characterize dysphagia and/or other esophageal symptoms in patients with PD, assess the prevalence of outflow obstruction as well as major or minor disorders of esophageal peristalsis leading to impaired esophageal clearance and highlight objective parameters that can help in the current management algorithm. Thirty-three consecutive patients with PD presenting with dysphagia, odynophagia, heartburn, regurgitation, chest pain, and weight loss underwent clinical and functional evaluation by high-resolution manometry (HRM). Esophagogastric junction (EGJ) outflow obstruction and major as well as minor disorders of peristalsis were then assessed using the Chicago classification (v3). Thirty-three PD patients with esophageal symptoms were enrolled in the study; 12 of them reported weight loss that was considered as potentially reflecting underlying esophageal dysfunction. The median age of the patients was 70 years (range: 53-89 years), 24 (75%) were men. The majority (62%) experienced dysphagia, likely contributing to weight loss in 41% of patients. Odynophagia was rare (6%) while GER symptoms, such as heartburn, regurgitation, and chest pain were noted in 37%, 31%, and 28% of patients, respectively. Using the hierarchy of the Chicago classification, 12 patients (39%) exhibited EGJ outflow obstruction, 16 (48%) diffuse esophageal spasm (DES), 18 (55%), ineffective esophageal peristalsis (IEM), 16 (48%) fragmented peristalsis, and only 2 patients (6%) had normal HRM tracings. There were no patients with HRM features of achalasia. Dysphagia is common in patients with PD and is associated with a high prevalence of underlying motility disturbances as identified by HRM. The exact impact of these motility abnormalities on symptom induction and their role in influencing clinical management are unclear and will require further study.

Balloon-based esophageal cryoablation with a novel focal ablation device: dose-finding and safety in porcine and human models.

The new Cryoballoon Focal Ablation System (CbFAS), a through-the-scope catheter with battery-powered handle that delivers cryogenic fluid into an inflated balloon, differs from current cryotherapy methods used for treatment of Barrett's epithelium. In this dose-finding study, short- and long-term histopathological effects and safety of the CbFAS were evaluated. Cryoablations with (supra)therapeutic durations (4-24 seconds) were performed in pigs that survived for 12 or 48 hours or 4 or 28 days. Next, cryoablations (durations based on animal data) were performed in normal mucosa of esophageal cancer patients scheduled to undergo esophagectomy. The outcome parameters, the occurrence of any bleeding or perforation, the histological presence of edema, inflammation, and necrosis throughout the esophageal wall layers, were evaluated. A total of 60 cryoablations were performed in 11 pigs. 48 hour cryoablations with therapeutic durations (4-10 seconds) resulted in edema/inflammation as deep as the serosa and necrosis ranging from submucosa to serosa with a median depth of 3.2 mm. In 4 day cryoablations this was in the serosa, and muscularis tunica to serosa at a median depth of 4.5 mm, respectively. No necrosis or inflammation remained after 28 days, not even after supratherapeutic cryoablation (12-24 seconds). No acute or delayed bleeding or perforation was observed. Next, eight 6-second cryoablations were performed in four patients. Direct postablation mucosal necrosis was observed; after 4 days necrosis and inflammation was limited to the submucosa. CbFAS cryoablation penetrates deeply into the esophageal wall layers resulting in severe early ablation. After 4 weeks, little injury and no fibrosis remain, even after supratherapeutic durations of administration, suggesting that CbFAS combines deep ablation with a potentially favorable safety profile.

Evaluation and management of patients with symptoms after anti-reflux surgery.

Over the past two decades, there has been an increase in the number of anti-reflux operations being performed. This is mostly due to the use of laparoscopic techniques, the increasing prevalence of gastroesophageal reflux disease (GERD) in the population, and the increasing unwillingness of patients to take acid suppressive medications for life. Laparoscopic fundoplication is now widely available in both academic and community hospitals, has a limited length of stay and postoperative recovery time, and is associated with excellent outcomes in carefully selected patients. Although the operation has low mortality and postoperative morbidity, it is associated with late postoperative complications, such as gas bloat syndrome, dysphagia, diarrhea, and recurrent GERD symptoms. This review summarizes the diagnostic evaluation and appropriate management of such postoperative complications. If a reoperation is needed, it should be performed by experienced foregut surgeons.

Multimodality evaluation of patients with gastroesophageal reflux disease symptoms who have failed empiric proton pump inhibitor therapy.

Patients with symptoms suggestive of gastroesophageal reflux disease (GERD), such as chest pain, heartburn, regurgitation, and dysphagia, are typically treated initially with a course of proton pump inhibitors (PPIs). The evaluation of patients who have either not responded at all or partially and inadequately responded to such therapy requires a more detailed history and may involve an endoscopy and esophageal biopsies, followed by esophageal manometry, ambulatory esophageal pH monitoring, and gastric emptying scanning. To assess the merits of a multimodality 'structural' and 'functional' assessment of the esophagus in patients who have inadequately controlled GERD symptoms despite using empiric PPI, a retrospective cohort study of patients without any response or with poor symptomatic control to empiric PPI (>2 months duration) who were referred to an Esophageal Studies Unit was conducted. Patients were studied using symptom questionnaires, endoscopy (+ or - for erosive disease, or Barrett's metaplasia) and multilevel esophageal biopsies (eosinophilia, metaplasia), esophageal motility (aperistalsis, dysmotility), 24-hour ambulatory esophageal pH monitoring (+ if % total time pH < 4 > 5%), and gastric emptying scanning (+ if >10% retention at 4 hours and >70% at 2 hours). Over 3 years, 275 patients (147 men and 128 women) aged 16-89 years underwent complete multimodality testing. Forty percent (n= 109) had nonerosive reflux disease (esophagogastroduodenoscopy [EGD]-, biopsy-, pH+); 19.3% (n= 53) had erosive esophagitis (EGD+); 5.5% (n= 15) Barrett's esophagus (EGD+, metaplasia+); 5.5% (n= 15) eosinophilic esophagitis (biopsy+); 2.5% (n= 7) had achalasia and 5.8% (n= 16) other dysmotility (motility+, pH-); 16% (n= 44) had functional heartburn (EGD-, pH-), and 5.8% (n= 16) had gastroparesis (gastric scan+). Cumulative symptom scores for chest pain, heartburn, regurgitation, and dysphagia were similar among the groups (mean range 1.1-1.35 on a 0-3 scale). Multimodality evaluation changed the diagnosis of GERD in 34.5% of cases and led to or guided alternative therapies in 42%. Overlap diagnoses were frequent: 10/15 (67%) of patients with eosinophilic esophagitis, 12/16 (75%) of patients with gastroparesis, and 11/23 (48%) of patients with achalasia or dysmotility had concomitant pathologic acid reflux by pH studies. Patients with persistent GERD symptoms despite empiric PPI therapy benefit from multimodality evaluation that may change the diagnosis and guide therapy in more than one third of such cases. Because symptoms are not specific and overlap diagnoses are frequent and multifaceted, objective evidence-driven therapies should be considered in such patients.

The Kagoshima consensus on esophageal achalasia.

Esophageal achalasia is a primary esophageal motility disorder characterized by lack of peristalsis and a lower esophageal sphincter that fails to relax appropriately in response to swallowing. This article summarizes the most salient issues in the diagnosis and management of achalasia as discussed in a symposium that took place in Kagoshima, Japan, in September 2010 under the auspices of the International Society for Diseases of the Esophagus.

Endoscopic ablation therapy of Barrett's esophagus.

Barrett's esophagus (BE) is an important risk factor for esophageal carcinoma and its incidence is rising. Amongst the various available endoscopic ablative therapies, radiofrequency ablation (RFA) is currently regarded as the most promising one, since RFA achieves high eradication rates of dysplasia and intestinal metaplasia with minimal complications. Patients with BE are advised to undergo regular endoscopic surveillance for dysplasia or cancer and endoscopy with four quadrant biopsy sampling at intervals of 1-2 cm of the entire length of BE remains the current standard for the detection of dysplasia or cancer. The management of BE depends on the histology of the biopsy specimens obtained during endoscopy, which includes non-dysplastic BE (ND-BE), low grade dysplasia, high grade dysplasia and adenocarcinoma. However, histological evaluation of dysplasia is fraught with error because of inter-observer variability even among expert gastrointestinal pathologists, and as a result, it often leads to false-negative or false-positive diagnoses. Non-dysplastic mucosa in BE shows clonal molecular aberrations, loss of cell cycle control, and other features of "neoplasia". These changes occur prior to morphologic expression of neoplasia (dysplasia). Given the difficulties of dysplasia assessment in mucosal biopsies, the molecular characteristics of ND-BE and LGD, and safe and effective profiles of RFA, this technique should be considered as a treatment option for the whole spectrum of BE patients.

Endoscopic evaluation of esophago-gastro-jejunostomy in rat model of Barrett's esophagus.

Endoscopy can be used to monitor the onset of metaplastic transformation and to observe the progression of neoplasia in small animal models of Barrett's esophagus. By avoiding animal sacrifice, the natural history of this disease can be studied in a longitudinal fashion. We aim to characterize the endoscopic features of esophageal mucosa at various stages of the metaplasia-dysplasia-carcinoma sequence in a rat reflux model of Barrett's for comparison with histology. Acid and bile reflux was produced by introducing a side-to-side esophago-gastro-jejunostomy in Sprague-Dawley rats. Endoscopic examination of the distal esophagus was performed in 24 surgically altered and 4 control rats, between weeks 24 and 36 after the operation in 4-week intervals, and all rats were biopsied and sacrificed at 36 weeks. Endoscopic images were classified based on the surface mucosal patterns of the distal esophagus and then compared with histology. The endoscopic appearance was classified as: (i) normal, characterized by a smooth surface; (ii) intestinal metaplasia, defined as elevated plaques/ridges, deep grooves, and thin linear folds; (iii) dysplasia, indicated by coarse folds/grooves, meshlike villi, and foveolar appearance; and (iv) carcinoma, suggested by irregular-shaped mass lesions with ulcerations. The endoscopic criteria for intestinal metaplasia yielded a sensitivity of 100% in comparison with histology. Intestinal metaplasia with high-grade dysplasia was found in two rats and with low-grade dysplasia in three rats. Both focally invasive squamous cell carcinoma and invasive adenocarcinoma were found in one rat. Small animal endoscopy in a rat model of Barrett's esophagus can be used to perform surveillance, classify mucosal patterns, observe the onset of intestinal metaplasia, and monitor the progression of neoplastic transformation, representing a useful tool for studying the natural history of this disease.

A pilot study to assess the safety and efficacy of the Third Eye retrograde auxiliary imaging system during colonoscopy.

BACKGROUND AND STUDY AIMS: Routine colorectal cancer screening, utilizing optical colonoscopy, has been shown to reduce the incidence and mortality rate of colorectal cancer. Despite its prevalence as the "gold standard" for neoplasia detection, the quality of colonoscopy screening is hindered by missed, undiagnosed lesions that may go undetected when located on the proximal aspect of haustral folds, rectal valves, the ileocecal valve, and/or flexures. The aim of this phase I feasibility trial is to assess the safety and efficacy of a new retrograde auxiliary imaging device, Third Eye Retroscope (Avantis Medical Systems, Inc., Sunnyvale, California, USA), used with optical colonoscopy to improve diagnostic yield. PATIENTS AND METHODS: A total of 29 consecutive patients were enrolled in this phase I single-institution prospective series. Primary efficacy endpoint was identification of polyps in the retrograde image that were not identified in the antegrade image during colonoscope withdrawal. RESULTS: Of the 29 patients enrolled, 24 patients were treated and 34 out of a total of 38 polyps (classified as either adenoma or hyperplasia) were identified in the antegrade image. An additional four polyps, three hyperplastic and one adenoma, were identified in the retrograde image, and were detected on the proximal aspect of haustral folds during the colonoscope withdrawal, resulting in an 11.8% increase in diagnostic yield. No adverse events were encountered during the study. CONCLUSION: A retrograde auxiliary imaging device used in conjunction with a standard optical colonoscope proved to be safe, technically feasible, and clinically promising. A phase II multi-institutional study is currently underway to further evaluate this device.

Physiological and molecular analysis of acid loading mechanisms in squamous and columnar-lined esophagus.

SUMMARY: Barrett's esophagus (BE) may be an adaptive cellular response to repeated acid exposure. The aims of this study were to compare intracellular acid loading in BE cells with normal squamous esophageal cells. Primary squamous and BE cells were obtained endoscopically and cultured for up to 24 h. Barrett's adenocarcinoma cell lines TE7 and OE-33 were compared with a normal esophageal (NE) cell line OE-21. Extracellular pH was lowered to 6.0 using HCl; specific ion exchangers were blocked pharmacologically and pH microfluorimetry was performed using 2'7'-bis(carboxyethyl)-5(6)-carboxyfluorescein. The effect of prolonged acid preincubations and repeated acid exposure on acid loading and recovery were examined. Acid loading was greater in primary BE than NE cells (DeltapHi -0.22 +/- 0.08 vs.-0.13 +/- 0.01) and maximal in the BE carcinoma cell line TE7 (DeltapHi -0.30 +/- 0.01). Whereas TE7 cells were able to recover fully from repeated acid exposure, OE-21 cells remained profoundly acidic. BE primary and transformed cells utilize DIDS inhibitable sodium-independent chloride/bicarbonate exchange as well as sodium/hydrogen ion exchange for acid loading. In contrast, SE only requires sodium-independent chloride/bicarbonate exchange for acidification. The degree of acid loading is greater in BE than NE cells and it occurs via dual ion exchangers similar to gastric mucosa. Only Barrett's epithelial cells can maintain a physiological pHi following prolonged and repeated reflux exposure, which may confer a teleological advantage.

Dynamic effects of acid on Barrett's esophagus. An ex vivo proliferation and differentiation model.

Barrett's esophagus (BE), or specialized intestinal metaplasia, is a premalignant heterogeneous epithelium associated with reflux and an increased risk for adenocarcinoma. Since acid is a major component of refluxate, we investigated its effects ex vivo on cell differentiation as determined by villin expression; and on cell proliferation, as determined by tritiated thymidine incorporation and proliferating cell nuclear antigen expression. To mimic known physiological conditions, endoscopic biopsies of normal esophagus, BE, and duodenum were exposed, in organ culture, to acidified media (pH 3-5) either continuously, or as a 1-h pulse and compared with exposure to pH 7.4 for up to 24 h. Before culture, villin expression was noted in 25% of BE samples, and increased after 6 or 24 h of continuous acid to 50% or 83% of BE samples, respectively. Increased villin expression correlated with ultrastructural maturation of the brush border. In contrast, an acid-pulse followed by culture at pH 7.4, did not alter villin expression in BE. Moreover, continuous acid exposure blocked cell proliferation in BE, whereas, an acid-pulse enhanced cell proliferation, as compared to pH 7.4. Based on our ex vivo findings, we propose a model in which the diverse patterns of acid exposure in vivo may contribute to the observed heterogeneity and unpredictable progression to neoplasia of BE.

Clostridium difficile toxin A stimulates intracellular calcium release and chemotactic response in human granulocytes.

Clostridium difficile, a common enteric pathogen, mediates tissue damage and intestinal fluid secretion by release of two protein exotoxins: toxin A, an enterotoxin, and toxin B, a cytotoxin. Because toxin A elicits an intense inflammatory reaction in vivo, we studied the effects of highly purified C. difficile toxins on activation of human granulocytes. Toxin A at concentrations of 10(-7) to 10(-6) M, but not toxin B, elicited a significant chemotactic and chemokinetic response by granulocytes that was comparable with that induced by the chemotactic factor N-FMLP (10(-7) M). Neither toxin stimulated release of superoxide anion from granulocytes. Toxin A produced a rapid, transient rise in cytosolic [Ca2+]i, as measured by quin 2 fluorescence. Pertussis toxin and depletion of intra- and extracellular calcium blocked the toxin A effect on cytosolic [Ca2+]i. These findings suggest that the inflammatory effects of C. difficile toxin A in the intestine may be related to its ability to mobilize intracellular Ca2+ and elicit a chemotactic response by granulocytes.

Long-term use of proton pump inhibitors does not affect the frequency, growth, or histologic characteristics of colon adenomas.

BACKGROUND: The clinical significance of the trophic effects of long-term proton pump inhibitors (PPI)-related hypergastrinemia on colon polyps remains unknown. AIM: To study the frequency, growth, and histology of colon polyps in patients on chronic PPI therapy (cases), compared to those not receiving acid suppression (controls). METHODS: Medical records of 2868 consecutive patients who underwent two or more colonoscopies, performed 3 or more months apart were reviewed. Cases (116) that used PPIs between the two colonoscopies were then compared to controls (194). RESULTS: Demographics and risk factors for colon cancer were comparable between the two groups. At baseline the mean frequency and size of adenomatous polyps were similar in cases and controls (P > 0.05) and at follow-up, these were 0.89 and 1.18 (P > 0.05; 95% CI of -0.08 to 0.66) and 4.09 mm and 4.00 mm (P > 0.05; 95% CI -2.29 to 2.11), respectively with no significant change. However, control group had a higher mean frequency and size of hyperplastic polyps at baseline as well as at follow-up colonoscopy (P < 0.05). CONCLUSIONS: The long-term use of PPI does not influence the frequency, growth, or histology of adenomatous polyps, but is associated with a reduction in both baseline and interval development of hyperplastic polyps.

The effects of esomeprazole combined with aspirin or rofecoxib on prostaglandin E2 production in patients with Barrett's oesophagus.

BACKGROUND: Reducing mucosal cyclo-oxygenase-2 and prostaglandin E(2) production and suppressing intraoesophageal acid may be effective chemopreventive strategies in patients with Barrett's oesophagus. AIM: To compare the effects of aspirin and rofecoxib when administered with esomeprazole on prostaglandin E(2) production, cyclo-oxygenase-2 expression and proliferating cell nuclear antigen expression in patients with Barrett's oesophagus. METHODS: This exploratory, multicentre, randomized, open-label, four-way crossover study in 45 patients with Barrett's oesophagus evaluated prostaglandin E(2) content, proliferating cell nuclear antigen expression, and cyclo-oxygenase-2 expression after 10 days of sequential treatments with: esomeprazole 40 mg twice daily plus aspirin 325 mg once daily (E40 b.d. + A325); E40 b.d. plus rofecoxib 25 mg once daily (E40 b.d. + R25); E40 b.d.; and rofecoxib 25 mg once daily (R25). RESULTS: Prostaglandin E(2) content reduction in Barrett's oesophagus tissue was significantly greater with E40 b.d. + A325 compared with E40 b.d. + R25, E40 b.d. or R25 (P < 0.05). All treatments containing E40 b.d. significantly decreased proliferating cell nuclear antigen expression from baseline (P < 0.05). None of the treatments significantly reduced cyclo-oxygenase-2 expression. CONCLUSIONS: The combined treatment of esomeprazole 40 mg b.d. and aspirin 325 mg significantly decreased mucosal prostaglandin E(2) content and all treatments containing esomeprazole significantly reduced proliferating cell nuclear antigen expression in patients with Barrett's oesophagus.

Expression of HLA class I antigens in sporadic adenomas and histologically normal mucosa of the colon.

The loss of HLA antigens by neoplastic cells is considered important for tumor growth and metastasis, inasmuch as it may allow tumors to escape immune surveillance. We have observed reduced expression of HLA antigens in sporadic colon cancer and adenomas from familial adenomatous polyposis patients. We now studied the expression of HLA class I antigens in patients with sporadic adenomas, which are precursors of colorectal cancer. Expression of HLA class I antigens was studied by immunohistochemistry in (a) sporadic colon adenomas, (b) histologically normal mucosa distant from the adenomas, (c) histologically normal colonic mucosa from patients with history of sporadic colon adenomas, and (d) colonic mucosa from normal subjects. HLA class I antigen expression was moderately reduced in 56% and severely reduced in 44% of the adenomas; this reduction was significant when compared to controls (P < 0.0001). The reduction of HLA class I expression in adenomas was related to the grade of dysplasia of the adenomas. HLA class I expression of normal appearing mucosa was decreased in 76% of patients with adenoma (P < 0.0001) and in 54% of patients with history of adenoma (P < 0.005) compared to normal controls. These changes were antigen specific, inasmuch as the expression of carcinoembryonic antigen, a surface antigen, was not affected. Our findings suggest that reduced HLA class I expression is an early event in the cell transformation process from normal to neoplastic state, preceding in many cases the onset of histological changes. HLA class I could be potentially used as a premalignant marker in the colon.

Review article: the role of antisecretory therapy in the management of non-variceal upper gastrointestinal bleeding.

Non-variceal, upper gastrointestinal bleeding accounts for 300,000 hospitalizations annually in the US and the risk of rebleeding and mortality remain high. The aim of this study was to review the incidence and causes of non-variceal upper gastrointestinal haemorrhage, criteria for early discharge, risk stratification and intravenous vs. oral proton-pump inhibitor use. Peptic ulcer disease accounts for 45% of all admissions for upper gastrointestinal bleeding. Clinical and endoscopic predictors of adverse outcome have been identified. The Rockall scoring system identifies patients who can be considered for early discharge after endoscopy. Evidence supports the use of intravenous proton-pump inhibitor therapy for patients with bleeding ulcers associated with high-risk stigmata. Patients who are clinically stable and in whom upper endoscopy has shown an ulcer with a clean base or a flat pigmented spot have a low risk for rebleeding and may be discharged early on oral proton-pump inhibitor therapy. Proton-pump inhibitor treatment reduces ulcer rebleeding but does not affect overall mortality. In the US, most patients with ulcer bleeding have low-risk stigmata, and thus, can be treated with oral proton-pump inhibitors and discharged early.