Rationale for surgical therapy of Barrett esophagus

Management strategies of Barrett's esophagus

Barrett’s esophagus is a condition resulting from chronic gastro-esophageal reflux disease with a documented risk of esophageal adenocarcinoma. Current strategies for improved survival in patients with Barrett's adenocarcinoma focus on detection of dysplasia. This can be obtained by screening programs in high-risk cohorts of patients and/or endoscopic biopsy surveillance of patients with known Barrett’s esophagus (BE). Several therapies have been developed in attempts to reverse BE and reduce cancer risk. Aggressive medical management of acid reflux, lifestyle modifications, antireflux surgery, and endoscopic treatments have been recommended for many patients with BE. Whether these interventions are cost-effective or reduce mortality from esophageal cancer remains controversial. Current treatment requires combinations of endoscopic mucosal resection techniques to eliminate visible lesions followed by ablation of residual metaplastic tissue. Esophagectomy is currently indicated in multifocal high-grade neoplasia or mucosal Barrett’s carcinoma which cannot be managed by endoscopic approach.

Laparoscopic surgical treatment for patients with short- and long-segment Barrett's esophagus: which technique in which patient?

Laparoscopic antireflux surgery is very successful in patients with short-segment Barrett's esophagus (BE), but in patients with long-segment BE, the results remain in discussion. In these patients, during the open era of surgery, we performed acid suppression + duodenal diversion procedures added to the antireflux procedure (fundoplication + vagotomy + antrectomy + Roux-en-Y gastrojejunostomy) to obtain better results at long-term follow-up. The aim of this prospective study is to present the results of 3 to 5 years' follow-up in patients with short-segment and long-segment or complicated BE (ulcer or stricture) who underwent fundoplication or the acid suppression-duodenal diversion technique, both performed by a laparoscopic approach. One hundred eight patients with histologically confirmed BE were included: 58 patients with short-segment BE, and 50 with long-segment BE, 28 of whom had complications associated with severe erosive esophagitis, ulcer, or stricture. After surgery, among patients treated with fundoplication with cardia calibration, endoscopic erosive esophagitis was observed in 6.9% of patients with short-segment BE, while 50% of patients with long-segment BE presented with positive acid reflux, persistence of endoscopic esophagitis with intestinal metaplasia, and progression to dysplasia (in 5% of cases; P = 0.000). On the contrary, after acid suppression-duodenal diversion surgery in patients with long-segment BE, more than 95.6% presented with successful results regarding recurrent symptoms and endoscopic regression of esophagitis. Regression of intestinal metaplasia to the cardiac mucosa was observed in 56.9% of patients with short-segment BE who underwent fundoplication and in 61% of those with long-segment BE treated with the acid suppression-duodenal diversion procedure. Patients with long-segment BE who experienced fundoplication alone presented no regression of intestinal metaplasia; on the contrary, progression to dysplasia was observed in 1 case (P = 0.049). Patients with short-segment BE can be successfully treated with fundoplication, but for patients with long-segment BE, we suggest performance of fundoplication plus an acid suppression-duodenal diversion procedure.

Effects of Nissen fundoplication on endoscopic endoluminal radiofrequency ablation of Barrett's esophagus

BACKGROUND

Endoscopic endoluminal radiofrequency ablation is achieving increasing acceptance as a mode of eliminating Barrett's metaplasia and, thus, reducing the risk of developing esophageal adenocarcinoma. It is believed that reducing exposure of the esophageal epithelium to acid is essential to achieve long-term ablation of Barrett's esophagus. However, it is unclear whether use of proton pump inhibitors or antireflux operations are more effective to accomplish this goal.

METHODS

All patients who underwent endoscopic endoluminal radiofrequency ablation with the BARRx device (BARRx Medical, Sunnyvale, CA) were reviewed for date of initial ablation, length of Barrett's epithelium, presence or performance of Nissen fundoplication, all follow-up endoscopy and treatment, and posttreatment biopsy results. Patients were categorized by presence of Nissen fundoplication and presence of Barrett's metaplasia or dysplasia by biopsy at least 12 months following ablation and at last endoscopic follow-up. Data were analyzed by Fisher's exact test and Mann-Whitney U-test.

RESULTS

Of 77 patients ablated, 47 had documented endoscopic follow-up at 12 months or longer following the ablation. Of these, 19 patients had Nissen fundoplication before, at the same time, or after ablation. Median length of Barrett's epithelium, with interquartile range (IQR), was 3 (2-12) cm in patients with fundoplication compared with 3 (2-7) cm without fundoplication (P = NS). Median follow-up was 15 (12-24) months in fundoplication patients compared with 12.5 (12-17) months without (P = NS). One of 19 patients with fundoplication had persistent or recurrent Barrett's epithelium, compared with 7 of 28 without fundoplication (P = 0.03). Of patients without fundoplication, those who had persistent or recurrent Barrett's had median Barrett's length of 10 cm (6-12 cm) compared with 3 cm (2-5 cm) in patients who had ablated Barrett's (P = 0.03). Follow-up length was similar in those with ablated epithelium, 15 months (12-19 months), compared with those with persistent or recurrent Barrett's, 12 months (12-13 months) (P = NS).

CONCLUSIONS

Patients who had fundoplication in conjunction with endoluminal radiofrequency ablation were more likely to achieve durable ablation compared with patients who were treated with proton pump inhibitor therapy. It appears that patients with long-segment Barrett's esophagus are at higher risk for persistent or recurrent Barrett's metaplasia. Consideration should be given for an antireflux operation in patients with long-segment Barrett's esophagus and planned endoluminal radiofrequency ablation.

Treatment modality and risk of development of dysplasia and adenocarcinoma in columnar-lined esophagus

Columnar metaplasia is the precursor lesion for esophageal adenocarcinoma, resulting from prolonged gastroesophageal reflux. The influence of the efficacy of reflux control on the development of neoplastic change in columnar-lined esophagus is not established. This study compares the rate of development of dysplasia and adenocarcinoma in patients with columnar metaplasia of the esophagus between patients treated pharmacologically and those treated with antireflux surgery. This study is a retrospective review of a cohort of patients enrolled in a multicenter national registry involving 738 patients from seven UK centers. Forty-one were treated with antireflux surgery, 42 with H2 receptor antagonist, 532 with proton pump inhibitor, and 114 with a combination of these medications. Nine had none of these medications or surgery. Total follow-up was 3697 years. Mean age and follow-up for patients treated medically were 61.6 and 4.96 years and surgically were 50.5 and 6.19 years, respectively. No patient in the surgical group developed high-grade dysplasia (HGD) or adenocarcinoma. Twenty patients treated medically developed adenocarcinoma and 10 developed HGD. Hazards ratio comparing pharmacological to surgical therapy for development of all grades of dysplasia and adenocarcinoma 1.77 (P = 0.272). Log rank test comparing antireflux surgery to pharmacological therapy for development of HGD or adenocarcinoma P = 0.1287 and for adenocarcinoma P = 0.2125. Although there was a trend towards greater efficacy of antireflux surgery over pharmacological therapy in reducing the development of dysplasia and adenocarcinoma, this did not reach statistical significance.

Impact of changing epidemiology of gastroesophageal reflux disease on its diagnosis and treatment

Gastroesophageal reflux disease (GERD) has emerged as one of the most common diseases in modern civilization. This article reviews selected changes in epidemiology of GERD during the past decade and provides information on treatment options with a focus on the impact of GERD and potential role of laparoscopic antireflux surgery in patients with diabetes mellitus, obesity, liver cirrhosis, at the extremes of life age and in immunocompromised individuals such as liver and lung transplant recipients.

Meta analysis: Cancer risk in Barrett's oesophagus

BACKGROUND

Risk of cancer in Barrett's oesophagus is reported to vary between studies and also between countries, where the studies were conducted as per several systematic reviews. Cancer incidence has implications on surveillance strategies.

AIM

To perform a meta-analysis to determine the incidence of oesophageal cancer in Barrett's oesophagus.

METHODS

Articles retrieved by MEDLINE search (English language, 1966-2004). Studies had to necessarily include verified Barrett's oesophagus surveillance patients, documented follow-up and cancer identified as the outcome measure. A random effects model of meta-analysis was chosen and results were expressed as mean (95% CI).

RESULTS

Forty-one articles selected for conventional Barrett's oesophagus (length >3 cm); eight included short segment Barrett's oesophagus (one additional article including only short segment Barrett's oesophagus). Cancer incidence was 7/1000 (6-9) person-years duration of follow-up (pyd), with no detectable geographical variation [UK 7/1000 (4-12) pyd, USA 7/1000 (5-9) pyd and Europe 8/1000 (5-12) pyd]. Cancer incidence in the UK was 10/1000 (7-14), when two large studies were excluded. Cancer incidence in SSBO was 6/1000 (3-12) pyd. When short segment Barrett's oesophagus compared to conventional Barrett's oesophagus, there was a trend towards reduced cancer risk [OR 0.55, (95% CI: 0.19-1.6), P = 0.25].

CONCLUSION

We found no geographical variations in Barrett's oesophagus cancer risk, but observed a trend towards reduced cancer risk in short segment Barrett's oesophagus. There is a time trend of decreasing cancer incidence.

Does the length of the columnar-lined esophagus change with time?

A number of previous studies have reported patients with Barrett's columnar metaplasia who have an increase or decrease in segment length over time. It is not clear whether patients who have an apparent shortening of the metaplastic segment are subsequently at a lower neoplastic risk and those whose segment length appears to increase are at a higher risk of adenocarcinoma development. The aim of this study was to investigate these issues by studying a large cohort of patients from the UK National Barrett's Oesophagus Registry. Medical records of 1533 patients registered with the UK National Barrett's Oesophagus Registry were examined from seven UK centers. Data were extracted on metaplastic segment length at surveillance endoscopies and histological findings on biopsy. Overall changes in segment length, variability in measurement and probability of the development of dysplasia and neoplasia over time were examined. At least two segment lengths were measured in 763 patients. The median change from measured diagnostic length to most outlying measured segment length was 3.0 cm, but overall there was no tendency for segment length to increase or decrease in the majority of patients with a follow up of up to 20 years. Most patients were treated with proton pump inhibitors. One hundred and eighty-six patients had three or more segment lengths over the first 10 years of follow up. No change in risk was demonstrated in these patients where length appeared to consistently increase with time or when it appeared to decrease. Overall, metaplastic columnar-lined esophagus segment length does not change over time, and when an apparent change is observed, this does not influence a risk of dysplasia or adenocarcinoma.

The effect of antireflux surgery on esophageal carcinogenesis in patients with barrett esophagus: a systematic review

OBJECTIVE

To determine whether patients with Barrett esophagus who undergo antireflux surgery differ from medically treated patients in incidence of esophageal adenocarcinoma and probability of disease regression/progression.

SUMMARY BACKGROUND DATA

Barrett esophagus is a risk factor for the development of esophageal adenocarcinoma. A question exists as to whether antireflux surgery reduces this risk.

METHODS

Query of PubMed (1966 through October 2005) using predetermined search terms revealed 2011 abstracts, of which 100 full-text articles were reviewed. Twenty-five articles met selection criteria. A review of article references and consultation with experts revealed additional articles for inclusion. Studies that enrolled adults with biopsy-proven Barrett esophagus, specified treatment-type rendered, followed up patients with endoscopic biopsies no less than12 months of instituting therapy, and provided adequate extractable data. The incidence of adenocarcinoma and the proportion of patients developing progression or regression of Barrett esophagus and/or dysplasia were extracted.

RESULTS

In surgical and medical groups, 700 and 996 patients were followed for a total of 2939 and 3711 patient-years, respectively. The incidence rate of esophageal adenocarcinoma was 2.8 (95% confidence interval, 1.2-5.3) per 1000 patient-years among surgically treated patients and 6.3 (3.6-10.1) among medically treated patients (P = 0.034). Heterogeneity in incidence rates in surgically treated patients was observed between controlled studies and case series (P = 0.014). Among controlled studies, incidence rates were 4.8 (1.7-11.1) and 6.5 (2.6-13.8) per 1000 patient-years in surgical and medical patients, respectively (P = 0.320). Probability of progression was 2.9% (1.2-5.5) in surgical patients and 6.8% (2.6-12.1) in medical patients (P = 0.054). Probability of regression was 15.4% (6.1-31.4) in surgical patients and 1.9% (0.4-7.3) in medical patients (P = 0.004).

CONCLUSIONS

Antireflux surgery is associated with regression of Barrett esophagus and/or dysplasia. However, evidence suggesting that surgery reduces the incidence of adenocarcinoma is largely driven by uncontrolled studies.

Endobrachyœsophage : place de la chirurgie antireflux

The aim of this study was to review the literature about the effect of antireflux surgery on the metaplasia-dysplasia-adenocarcinoma sequence in patients with Barrett's oesophagus. Antireflux operations (by laparotomy or laparoscopy) can alter the natural history of Barrett's oesophagus, allowing disease stabilization in a substantial proportion of patients without high grade dysplasia at time of surgery. It also may induce complete or partial regression of Barrett's epithelium, especially for short segment of Barrett's oesophagus, but in unpredictable manner. While regression of low-grade dysplasia is commonly observed, histologic progression is rarely observed after effective antireflux surgery. However, ineffective antireflux surgery expose to histologic progression to high-grade dysplasia or adenocarcinoma. These data support the need for a long-term clinical, endoscopic, and histologic follow-up program after antireflux surgery in patients with Barrett's oesophagus.

Barrett esophagus: risk factors for progression to dysplasia and adenocarcinoma

OBJECTIVE

To evaluate risk factors for dysplasia and adenocarcinoma development in nondysplastic Barrett mucosa.

SUMMARY BACKGROUND DATA

The risk for patients with Barrett esophagus to develop esophageal adenocarcinoma is low, and most patients undergoing surveillance will not develop malignancy. Identification of risk factors may allow for more rational surveillance programs in which patients are stratified according to their individual risk of progressing to dysplasia and invasive adenocarcinoma.

METHODS

The development of dysplasia and esophageal adenocarcinoma was studied during long-term endoscopic and histologic surveillance in 140 patients with Barrett esophagus free from dysplasia. Risk factors for progression to dysplasia and adenocarcinoma were evaluated.

RESULTS

Median follow-up was 5.8 years. Forty-four patients (31.4%) developed low-grade dysplasia and 7 patients (5%) developed high-grade dysplasia or esophageal adenocarcinoma. Dysplasia development was significantly less common after antireflux surgery compared with conventional medical therapy. Low-grade dysplasia (relative risk = 5.5; 95% confidence interval, 1.1-28.6) and long duration of reflux symptoms (relative risk = 1.3; 95% confidence interval, 1.2-1.7) were independently associated with an increased risk of developing high-grade dysplasia or esophageal adenocarcinoma.

CONCLUSIONS

Successful antireflux surgery protects the Barrett mucosa from developing high-grade dysplasia and esophageal adenocarcinoma, possibly by better control of reflux of gastric contents. Low-grade dysplasia is the only clinically useful risk factor that permits stratification of the surveillance intervals according to the risk of the individual patient.

Fundoplication and the risk of esophageal cancer in gastroesophageal reflux disease: a Veterans Affairs cohort study

BACKGROUND AND AIMS

It has been proposed that fundoplication can reduce the risk of esophageal cancer in patients with gastroesophageal reflux disease (GERD). In this cohort study, we assessed the effect of fundoplication on the incidence of esophageal cancer.

METHODS

We identified all Veterans Affairs (VA) patients with GERD who had fundoplication between 1986 and 1990 and matched (1-2) to controls with GERD and no fundoplication and to controls with no GERD. We calculated incidence rates for esophageal cancer through October 2002 and examined the effect of fundoplication on the risk of esophageal cancer using Kaplan-Meier survival analysis and Cox proportional hazard analysis. We calculated and adjusted for the propensity score for receiving fundoplication.

RESULTS

We identified 946 patients who had fundoplication, 1,892 patients who had GERD without fundoplication, and 5,676 patients with no GERD. The mean age was 55 yr and 97.5% were men in all three groups. During a follow-up of 11,156 patient-years (PY), there were eight cases of esophageal cancer (72/100,000) in the fundoplication group. During a follow-up of 20,115 PY, there were eight cases of esophageal cancer (40/100,000) in the GERD without fundoplication group. During a follow-up of 59,439 PY, no patients in the group with no GERD developed esophageal cancer. The Kaplan-Meier analysis showed no significant difference in cumulative esophageal cancer rates between the fundoplication group and the GERD no-fundoplication group. The adjusted hazard ratio of esophageal cancer with fundoplication was 1.88 (95% CI: 0.70-5.03).

CONCLUSIONS

GERD is a risk factor for esophageal cancer, but there is insufficient evidence that fundoplication reduces that risk.

Does fundoplication change the risk of esophageal cancer in the setting of GERD?

The effect of a surgical antireflux procedure on the risk of cancer in those with GERD and Barrett's esophagus is unclear. Although some authorities have suggested that a surgical antireflux procedure might be superior to medical management for the prevention of cancer, the cumulative data do not demonstrate that those patients undergoing surgery have any decrement in cancer risk compared to those who receive medication. Most data available to assess the effect of surgery on cancer risk come from case series. These data are of very limited utility, because of differences in the baseline composition of groups undergoing medical and surgical therapy. Until more data are available, patients should not be advised to undergo surgical fundoplication as an antineoplastic measure.

Review article: anti-reflux surgery and endoluminal therapies

In the short term, fundoplication and antisecretory medication are equally effective in the management of gastro-oesophageal reflux disease. However, over the long term, the fundoplication wrap tends to become loose, and many surgical patients continue to take antisecretory medication after surgery. The operation is technically complex and takes a long time to learn. Inexperience of the individual surgeon is a major factor contributing to the occurrence of postsurgical complications. Fundoplication does not prevent the occurrence of Barrett's oesophagus nor its progression to oesophageal adenocarcinoma. There is no evidence to suggest that the procedure is less costly or more cost-effective than long-term maintenance therapy with antisecretory medications, especially if surgical failures and postsurgical complications are taken into account. Fundoplication represents an alternative to medical therapy in patients with gastro-oesophageal reflux disease who cannot or do not want to be on long-term maintenance therapy with antisecretory medication. Endoluminal procedures, such as radiofrequency ablation, endoscopic suturing and injection at the gastro-oesophageal junction, work only in mild forms of reflux disease. They fail to provide complete relief of reflux symptoms and do not heal erosive oesophagitis. All endoluminal procedures would have to undergo major technological improvements before they could become comparable with fundoplication or antisecretory therapy.

The Nissen fundoplication: indication, technical aspects and postoperative outcome

INTRODUCTION

Gastroesophageal reflux disease (GERD) is the most common foregut disease, with a great impact on quality of life and with intestinal, respiratory and cardiac symptoms and implications of carcinogenesis of the oesophagus. Medical therapy often fails, due to the complex pathophysiology of GERD. Surgery can cure the disease, since it is able to restore the anti-reflux barrier. It improves quality of life and prevents carcinogenesis.

METHODS

Review of the literature and presentation of our own experience and data in a series of more than 4,000 evaluated patients referred for suspected reflux disease, of whom 382 have been operated on.

CONCLUSION

The laparoscopic Nissen fundoplication is the most commonly used operation technique. It provides good long-term results in the majority of patients. However, due to an increase of outflow resistance of the oesophagus this operation is associated with some postoperative side effects. Therefore, alternative anti-reflux procedures may be indicated in selected patients.

A critical review of the diagnosis and management of Barrett's esophagus: the AGA Chicago Workshop

BACKGROUND & AIMS

The diagnosis and management of Barrett's esophagus (BE) are controversial. We conducted a critical review of the literature in BE to provide guidance on clinically relevant issues.

METHODS

A multidisciplinary group of 18 participants evaluated the strength and the grade of evidence for 42 statements pertaining to the diagnosis, screening, surveillance, and treatment of BE. Each member anonymously voted to accept or reject statements based on the strength of evidence and his own expert opinion.

RESULTS

There was strong consensus on most statements for acceptance or rejection. Members rejected statements that screening for BE has been shown to improve mortality from adenocarcinoma or to be cost-effective. Contrary to published clinical guidelines, they did not feel that screening should be recommended for adults over age 50, regardless of age or duration of heartburn. Members were divided on whether surveillance prolongs survival, although the majority agreed that it detects curable neoplasia and can be cost-effective in selected patients. The majority did not feel that acid-reduction therapy reduces the risk of esophageal adenocarcinoma but did agree that nonsteroidal antiinflammatory drugs are associated with a cancer risk reduction and are of promising (but unproven) value. Participants rejected the notion that mucosal ablation with acid suppression prevents adenocarcinoma in BE but agreed that this may be an appropriate strategy in a subgroup of patients with high-grade dysplasia.

CONCLUSIONS

Based on this review of BE, the opinions of workshop members on issues pertaining to screening and surveillance are at variance with published clinical guidelines.

Barrett's esophagus: the role of laparoscopic fundoplication

BACKGROUND

To review our early operative results and endoscopic findings after laparoscopic fundoplication for Barrett's esophagus (BE).

METHODS

From January 1995 through December 2000, 49 patients with BE (35 men and 14 women) underwent laparoscopic antireflux surgery. Median age was 54 years (range, 28 to 85 years). No patient had high-grade dysplasia; 6, however, had low-grade dysplasia. All 49 patients had gastroesophageal reflux symptoms. Heartburn was present in 41 patients (84%), dysphagia in 16 (33%), epigastric or chest pain in 9 (18%), and other symptoms in 16 (33%). A Nissen fundoplication was performed in 48 patients and a partial posterior fundoplication in 1. Forty-one patients (84%) had concomitant hiatal hernia repair.

RESULTS

There were no deaths. Complications occurred in 2 patients (4%). Follow-up was complete in 48 patients (98%) and ranged from 1 to 81 months (median, 29 months). Functional results were classified as excellent in 33 patients (69%), good in 9 (19%), fair in 5 (10%), and poor in 1 (2%). Thirty-three patients (67%) underwent postoperative surveillance esophagoscopy with biopsy. Nine patients (18%) had total regression of BE and 3 (6%) had a decrease in total length. In the 6 patients with preoperative low-grade dysplasia, dysplasia was not found in 4, remained unchanged in 1, and progressed to in situ adenocarcinoma in 1.

CONCLUSIONS

Laparoscopic fundoplication is effective in controlling symptoms in the majority of patients with BE. While disappearance of BE may occur in some patients, the possibility of developing esophageal adenocarcinoma is not eliminated by laparoscopic fundoplication. Therefore, endoscopic surveillance should continue.

Does a surgical antireflux procedure decrease the incidence of esophageal adenocarcinoma in Barrett's esophagus? A meta-analysis

OBJECTIVE

The risk of adenocarcinoma of the esophagus is increased among those with Barrett's esophagus (BE). Whether the risk of cancer in the setting of BE can be decreased by a surgical antireflux procedure (SARP) is unclear. This study compared the reported incidence of esophageal adenocarcinoma in subjects with BE who underwent SARP with those with BE who had medical management.

METHODS

We used MEDLINE to perform a meta-analysis of the English language literature published from 1966 through October 2001. We reviewed abstracts found with the search term "Barrett's esophagus" and the following: "adenocarcinoma," "esophageal neoplasm," "proton pump inhibitor," "fundoplication," or "antireflux procedure." Study entry criteria included 1) trial or cohort study with a report of cancer risk expressible in cancers per patient-year, 2) histologic confirmation of BE and any adenocarcinomas, and 3) adequate description of intervention (medical vs SARP). Data were abstracted by two reviewers using standardized forms. Subgroup comparisons were made using only medical management studies published in the last 5 yr. Multivariable regression controlling for subject age, country of origin, and BE length was performed.

RESULTS

We reviewed 1247 abstracts, and 34 met the inclusion criteria. There were a cumulative 4678 patient-years of follow-up in the SARP group and 4906 patient-years in the medical group. The cancer incidence rate in the SARP group was 3.8 cancers/1000 patient-years, compared with 5.3 in the medical group (p=0.29). Similarly, there was no significant difference between cancer rates when comparing SARP with medical series reported in the last 5 yr (3.8/1000 patient-years vs 4.2/1000 patient-years, p=0.33). Multivariate analysis controlling for subject age, country of origin, and BE length did not alter these findings.

CONCLUSION

The reported risk of adenocarcinoma in subjects with BE is low and not significantly decreased by a surgical antireflux procedure. Antireflux surgery in the setting of BE should not be recommended as an antineoplastic measure.

Antireflux surgery for Barrett's oesophagus

Barrett's oesophagus is usually the result of severe reflux disease. Relief of reflux symptoms is the primary aim of treatment in patients with Barrett's oesophagus who do not have high-grade dysplasia. Some studies with medium-term (2-5 years) follow up show that antireflux surgery can provide good or excellent symptom control, with normal oesophageal acid exposure, in more than 90% of patients with Barrett's oesophagus. Antireflux surgery, but not medical therapy, can also reduce duodenal nonacid reflux to normal levels. There is no conclusive evidence that antireflux surgery can prevent the development of dysplasia or cancer, or that it can reliably induce regression of dysplasia, and patients with Barrett's oesophagus should therefore remain in a surveillance programme after operation. Some data suggest that antireflux surgery can prevent the development of intestinal metaplasia (IM) in patients with reflux disease but no IM. The combination of antireflux surgery plus an endoscopic ablation procedure is a promising treatment for patients with Barrett's oesophagus with low-grade dysplasia.

Acid- and bile-induced PGE(2) release and hyperproliferation in Barrett's esophagus are COX-2 and PKC-epsilon dependent

Barrett's esophagus (BE) results from acid and bile reflux and predisposes to cancer. To further understand the mechanisms of acid- and bile-induced hyperproliferation in BE, we investigated the release of PGE(2) in response to acid or bile salt exposure. Biopsies of esophagus, BE, and duodenum were exposed to a bile salt mixture as a 1-h pulse and compared with exposure to pH 7.4 for up to 24 h, and PGE(2) release, cyclooxygenase-2 (COX-2), and protein kinase C (PKC) expression were compared. Similar experiments were also performed with acidified media (pH 3.5) alone, in the presence or absence of bisindolylmaleimide (BIM), a selective PKC inhibitor, and NS-398, a COX-2 inhibitor. One-hour pulses of bile salts or acid significantly enhanced proliferation, COX-2 expression, and PGE(2) release in BE. In contrast, the combination pulse of acid and bile salts had no such effect. Treatment with either BIM or NS-398 led to a dramatic decrease in PGE(2) release in BE explants and a suppression of proliferation. The acid- or bile salt-mediated hyperproliferation is related to PGE(2) release. Acid- and bile salt-induced induction of COX-2 and PKC may explain, at least in part, the tumor-promoting effects of acid and bile in BE.

Rofecoxib inhibits cyclooxygenase 2 expression and activity and reduces cell proliferation in Barrett's esophagus

BACKGROUND & AIMS

Cyclooxygenase 2 (COX-2) is overexpressed in Barrett's esophagus and adenocarcinoma and up-regulated by acid or bile salt exposure. COX-2 inhibition with the selective inhibitor rofecoxib may be important in chemoprevention of esophageal adenocarcinoma by decreasing cell proliferation.

METHODS

Biopsy specimens of esophagus, Barrett's esophagus, and duodenum were obtained at baseline from 12 patients and were compared with biopsy specimens obtained after 10 days of therapy with rofecoxib 25 mg orally daily. All patients were maintained asymptomatic on their proton pump inhibitor therapy throughout the study. COX-2 expression, proliferating cell nuclear antigen (PCNA) expression (proliferation marker), and prostaglandin E2 (PGE2) biopsy content (marker of COX activity) were assessed by immunoblotting and enzyme immunoabsorbence assays.

RESULTS

At baseline, COX-2 expression was 3-fold higher in Barrett's esophagus than esophagus and duodenum (P < 0.05). After rofecoxib therapy, COX-2 expression in Barrett's esophagus decreased by 77% (P < 0.005). Similarly at baseline, PGE2 content was 2-fold higher in Barrett's esophagus than esophagus or duodenum. After rofecoxib therapy, PGE2 content decreased in Barrett's esophagus by 59% (P < 0.005). At baseline, PCNA expression was also 2-fold higher in Barrett's esophagus than squamous esophagus and duodenum (P < 0.005). After rofecoxib therapy, PCNA expression in Barrett's esophagus decreased by 62.5% (P < 0.005).

CONCLUSIONS

Rofecoxib 25 mg orally once daily reduces COX-2 expression, PGE2 release, and cell proliferation in Barrett's esophagus. Together with acid suppressive therapy, rofecoxib may be a promising chemoprevention agent against dysplasia and esophageal adenocarcinoma.