Antireflux Stent Research Articles

The Use of Self-Expanding Stents in Esophageal and Gastroesophageal Junction Cancer Palliation: A Meta-Analysis and Meta-Regression Analysis of Outcomes

The objective of this study was to examine the impact of self-expanding stents versus locoregional treatment modalities in the setting of esophageal cancer palliation. The present meta-analysis pooled the effects of outcomes of 1,027 patients enrolled in 16 randomized controlled trials. The meta-analysis revealed an advantage to the use of stents compared to locoregional modality treatments with respect to the number of patients requiring reinterventions, although the latter treatment arm had a higher 1-year survival. No difference was observed between the use of the antireflux stents and conventional stents in relieving reflux. Previous chemoradiotherapy had no impact on complications, procedural deaths, and overall patient survival. Differences in outcomes among stents were minimal. Conventional self-expanding stents and anti-reflux stents are equally effective. Although the risk difference for 1-year survival favoured locoregional palliative treatment modalities, the latter were associated with a higher number of patients requiring reintervention.

Antireflux stent versus conventional stent in the palliation of distal esophageal cancer. A randomized, multicenter clinical trial

Objective. Patients with incurable distal esophageal or cardia cancer often need palliative stenting to relieve their dysphagia but stents passing through the cardia can cause reflux and aspiration, leading to a reduced health-related quality of life (HRQL). This study addressed the hypothesis that antireflux stenting improves HRQL compared to conventional stenting. Material and methods. In a single-blind, multicenter, randomized trial in patients with inoperable esophageal or cardia cancer requiring palliative stenting passing through the cardia, 65 patients were stented. Patients received either an antireflux stent (Esophageal Z-Stent with Dua antireflux valve; n = 28) or a conventional stent (Esophageal Z-stent, Ultraflex or Wallstent; n = 37). Validated questionnaires (European Organization for Research and Treatment of Cancer QLQ-C30 and QLQ-OES18) were used to collect information on HRQL at baseline and 1 and 3 months after stenting. Main outcome measurements were differences in HRQL scores between baseline and 1 and 3 months after stenting. Results. Scores for most aspects of HRQL were similar in the two groups, and no statistically significant differences were found. Some general symptoms however showed clinically relevant improvement in the antireflux stent group, while esophageal-specific symptoms such as dysphagia seemed clinically better, and symptoms of reflux were clinically reduced in the conventional stent group but not in the antireflux stent group. Conclusion. This study, although limited in size, provided no obvious support for using the antireflux stent in preference to the conventional stent in the palliation of distal esophageal or cardia cancer from an HRQL perspective.

Fracture of a covered self-expanding antireflux stent in two patients with distal esophageal carcinoma

Fracture of a covered self-expanding antireflux stent in two patients with distal esophageal carcinoma

Randomised comparison of the FerX Ella antireflux stent and the ultraflex stent: Proton pump inhibitor combination for prevention of post‐stent reflux in patients with esophageal carcinoma involving the esophago‐gastric junction

Metal stents placed across the gastroesophageal junction in patients with malignant dysphagia frequently present with reflux symptoms. We compared an antireflux stent with a standard open stent used in combination with proton pump inhibitor medication. Forty-nine patients with dysphagia due to inoperable carcinoma in the lower third of the esophagus were randomly selected to receive either a antireflux valve stent (FerX-Ella) (n = 22) or a covered standard open stent (Ultraflex), which was combined with proton pump inhibitors such as omeprazole (n = 26). The technical success, the presence of reflux, and complications were recorded. Reflux was seen in 3/22 patients (13.6%) in the FerX-Ella group and in 2/26 patients (7.7%) in the Ultraflex and proton pump inhibitor combination group (P-value not significant). In both groups, a significant improvement in the dysphagia score was seen and no statistically significant difference was detected between the two groups (P = 0.84). The FerX-Ella stents migrated more frequently (32%) than the Ultraflex stents (23%). This also necessitated surgical intervention more frequently in the FerX-Ella group (2/22, 9.1%) compared to the Ultraflex group (1/26, 3.8%). The antireflux stent had no demonstrable advantages compared to the combination of standard open stent and proton pump inhibitor medication.

Endoscopic stenting of esophageal cancer: the clinical impact

To summarize the most relevant articles with regard to endoscopic stenting of esophageal cancer published in 2006. In 2006, there were two studies on esophageal stents with experimental designs and adequate size to contribute to an evaluation of esophageal stent technology. A study on an antireflux stent will not measurably change the current use of this device, but emphasizes the need for additional investigation. A study on a self-expanding plastic stent was the largest study to date demonstrating a self-expanding plastic stent to be comparable to self-expanding metal stents. Other published studies in 2006 on esophageal stents include review articles, case reports and small case series that are not addressed in this review. Self-expanding metal stents remain an important option for the treatment of patients with tracheoesophageal fistulae and esophageal malignancies. Recent innovations are dominated by a shift toward self-expanding esophageal stents that are potentially removable. Such potentially removable stents allow for expanded clinical applications and will be the focus of publications in 2007.

Superiority of anti-reflux stent compared with conventional stents in the palliative management of patients with cancer of the lower esophagus and esophago-gastric junction: results of a randomized clinical trial

Palliation of inoperable esophageal cancer with covered stents aims to relieve progressive dysphagia and improve health-related quality of life (HRQoL). Introducing a stent across the esophagogastric junction in lower third tumors may predispose to unchecked gastro-esophageal reflux (GER). Esophageal stents incorporating an anti-reflux valve have been introduced to address this problem. We prospectively compared an anti-reflux stent with a standard stent in the palliation of inoperable lower third esophageal tumors. Forty-nine consecutive patients with malignant dysphagia were randomized to receive a standard (n = 25, group 1) or an anti-reflux stent (n = 24, group 2). HRQoL was assessed before stenting, at 1 week and at 2 months, utilizing European Organization for Research and Treatment of Cancer questionnaires QLQ-C30, QLQ-OES24 and reflux questionnaires. Esophageal pH testing was performed within 1 week of the stent insertion. Detailed statistical analysis was employed to assess general QoL, symptoms and pH scores in both groups. Both groups reported significantly improved QoL, health and dysphagia scores at 1 week and 2 months after stenting. Group 2 patients reported significantly (P < 0.05) better DeMeester symptom, general reflux scores, and normal pH profile at 1 week. At 2 months DeMeester symptom scores were significantly (P < 0.05) better in group 2 compared with group 1. Standard and anti-reflux stents afford comparable relief from dysphagia and improved quality of life in patients with inoperable lower third esophageal cancer. Anti-reflux stents, however, controlled symptomatic and physiologically relevant reflux and should therefore be considered as optimal palliation in this cohort.

An antireflux stent versus conventional stents for palliation of distal esophageal or cardia cancer: a randomized clinical study

Self-expandable metal stents placed across the esophagogastric junction for palliative treatment of malignant strictures may lead to gastroesophageal reflux and pulmonary aspiration. This study compared the effects of a Dua antireflux stent with those of a conventional stent. Patients with incurable cancer of the distal esophagus or gastric cardia were randomly assigned to receive an antireflux stent (n = 19) or a standard stent (n = 22) at nine Swedish hospitals during the period September 1, 2003 to July 31, 2005. Complications were recorded at clinical follow-up visits. Survival rates were assessed through linkage to the Population Register. Dysphagia, reflux symptoms, esophageal pain, dyspnea, and global quality of life were assessed as changes in mean scores between baseline and 1 month after stent insertion through validated questionnaires. No technical problems occurred during stent placement in the 41 enrolled patients. Fewer patients with complications were observed in the antireflux stent group (n = 3) than in the standard group (n = 8), but no statistically significant difference was shown (p = 0.14). The survival rates were similar in the two groups (p = 0.99; hazard ratio, 1.0; 95% confidence interval, 0.5-2.0). The groups did not differ significantly in terms of studied esophageal or respiratory symptoms or quality of life. Clinically relevant improvement in dysphagia occurred in both groups. Dyspnea decreased after antireflux stent insertion (mean score change, -11), and increased after insertion of standard stent (mean score change, +21). Antireflux stents may be used without increased risk of complications, mortality, esophageal symptoms, or reduced global quality of life. These results should encourage large-scale randomized trials that can establish potentially beneficial effects of antireflux stents.

Antireflux biliary stents: Are they the solution to stent occlusions?

Endoscopic insertion of plastic or metal stents is a well-established treatment for malignant biliary obstruction. The major limitation of this technique is stent occlusion. Duodenobiliary reflux has been considered a key contributor to stent occlusion. The presence of plant fibers in 35% to 60% of occluded stents on confocal laser microscopy has further confirmed the presence of reflux when the stent is placed across the papilla. Antireflux stents address this problem by allowing normal antegrade flow but preventing reflux. Recent studies comparing these antireflux stents with the standard Tannenbaum stents have shown significantly prolonged patency. Although initial results are encouraging, larger randomized trials are required to establish efficacy.

Palliative therapy

There are a wide variety of palliative treatments for esophageal cancer. The aim of most treatments is to maintain oral food intake, which should stabilize or even improve quality of life. Stent placement is currently the most widely used treatment modality for palliation of dysphagia from esophageal cancer. Stent placement offers a rapid relief of dysphagia, however, the rate of complications (late hemorrhage) and recurrent dysphagia (stent migration, tumor overgrowth) is relatively high. The scientific evidence to advocate the use of anti-reflux stents for the prevention of gastro-esophageal reflux is currently too low. Photodynamic therapy is mostly used in North America; however, due to the high costs of the treatment, the long-lasting side effects and the necessity of repeated treatments, it is not an ideal treatment for palliation of malignant dysphagia. Nd:YAG laser is a relatively effective and safe treatment modality, although laser treatment is also expensive, technically difficult and requiring repeated treatment sessions at 4-6 weeks intervals. Single dose brachytherapy compares favorably to stent placement in long-term effectiveness and safety. Effective treatment strategies are probably 12 Gy given in one fraction or 16 Gy given in two fractions. Palliative chemotherapy offers response rates in recent trials (including partial and complete responses) ranging from 35% to 50%. Whether palliative chemotherapy also results in a survival benefit is not established yet. For clinical trials on palliation of esophageal cancer, the measurement of quality of life is an important outcome measure. The cancer-specific EORTC QLQ-C30 and the esophageal cancer-specific EORTC-OES-18 are validated measures for establishing quality of life status. For the future, a multimodality approach with stent placement or brachytherapy in combination with chemotherapy may be indicated.

Self-expanding metal stents in the palliation of malignant dysphagia: Outcome analysis in 100 consecutive patients*

SUMMARY. Patients with inoperable esophageal malignancy often undergo palliative self-expanding metal stent insertion. This analysis of cases shows that although such stents provide good palliation of dysphagia, complications frequently occur. Complications reported were pain after insertion, bleeding, food bolus impaction, stent migration and increased gastroesophageal reflux. Furthermore, in patients with esophageal adenocarcinoma, survival was less if the distal end of the stent entered the stomach, rather than lying entirely within the esophagus. Reduced survival, in this group with gastroesophageal junction tumors, may be a result of increased gastroesophageal reflux leading to pulmonary aspiration. Stents incorporating an antireflux valve have been shown to reduce symptomatic gastroesophageal reflux. It may be that such valves offer a survival advantage where stent insertion ablates the function of the lower esophageal sphincter. Further studies are needed to assess the role of antireflux stents on survival in patients with gastroesophageal junction tumors.

Management of Malignant Stricture of the Esophagogastric Junction with a Newly Designed Self-Expanding Metal Stent with an Antireflux Mechanism

When stents are placed across the esophagogastric junction for palliative treatment of malignant strictures, they may lead to esophagogastric reflux. The aim of this study was to compare the effectiveness of a newly designed antireflux stent with that of a standard open stent and a currently available antireflux stent (Dostent) in preventing gastroesophageal reflux symptoms in patients with inoperable cancer at the esophagogastric junction. Thirty-six consecutive patients with cancer at the esophagogastric junction were randomly assigned to undergo placement of a newly designed antireflux stent (n = 12), a Dostent (n = 12), or a standard open stent (n = 12). Technical and clinical success, dysphagia score, reflux symptoms, complications and ambulatory 24-h esophageal pH monitoring were assessed. The technical success rates were 100 %. After 1 week, dysphagia had improved in all patient groups ( P < 0.05), but the degree of improvement did not differ between the three groups. The DeMeester score was significantly lower in the group with the newly designed antireflux stent than in the other groups. The fraction of the total recording time during which esophageal pH was below 4 was 3.14 +/- 5.78 % using the newly designed antireflux stent, in comparison with 29.25 +/- 15.41 % in the Dostent group and 15.01 +/- 11.72 % in the standard open stent group ( P < 0.001). Fewer reflux episodes occurred with the newly designed antireflux stent than with the Dostent or standard open stent. There were no complications with any of the three stents. The newly designed antireflux stent is effective in relieving dysphagia caused by malignant cancer at the esophagogastric junction. The newly designed antireflux stent is significantly more effective in preventing gastroesophageal reflux than currently available antireflux stents.

Esophageal stents with antireflux valve for tumors of the distal esophagus and gastric cardia: a randomized trial

Self-expandable metal stents deployed across the gastroesophageal junction predispose to gastroesophageal reflux. The efficacy of a stent with an antireflux mechanism in preventing gastroesophageal reflux was assessed. Thirty patients with carcinoma of the distal esophagus or of the gastric cardia were randomized to receive either a stent with a windsock-type antireflux valve (FerX-Ella) (n = 15) or a standard open stent (n = 15) of the same design minus the valve. Gastroesophageal reflux was assessed by using standardized questionnaires and by 24-hour pH monitoring 14 days after treatment. Technical problems occurred during stent placement in 3 patients: migration (n = 2) and a problem with the introducing system (n = 1). Dysphagia improved from a median score of 3 (liquids only) to 1 (eat some solid food) in the antireflux group and from 3 to 0 (solid foods) in the open stent group ( p > 0.20). Reflux symptoms were reported by 3/12 patients (25%) with an antireflux stent and by 2/14 (14%) with an open stent. In 11 patients, 24-hour pH monitoring was obtained, and increased esophageal acid exposure (normal: <4%) was present with both types of stent: median 24-hour reflux time (9 patients) with the antireflux stent was 23% vs. 10% in (2 patients) with the open stent ( p = NS). Major complications occurred in 3 patients (20%) in each group and included bleeding (n = 3), severe pain (n = 2), and aspiration pneumonia (n = 1). The main cause of recurrent dysphagia was stent migration, which occurred in 7 of the 30 patients (23%). The FerX-Ella antireflux stent provided relief of dysphagia caused by malignancy of the distal esophagus and gastric cardia. However, the antireflux valve failed to prevent gastroesophageal reflux.

Esophageal Stents with Anti-Reflux Valve for Tumors Involving the Distal Esophagus and Gastric Cardia: A Randomized Trial

Background: Self-expanding metal stents deployed across the gastroesophageal junction predispose to gastroesophageal reflux. We assessed the efficacy of the FerX-Ella stent with an anti-reflux mechanism in preventing gastroesophageal reflux. Methods: Between April 2002 and May 2003, 30 patients with carcinoma of the distal esophagus or gastric cardia were randomized to receive either a FerX-Ella stent with a windsock-type anti-reflux valve (n=15) or a standard open FerX-Ella stent (n=15). Patients were followed prospectively and were asked to undergo 24-hour pH monitoring 14 days after treatment. Results: Technical problems during placement occurred in 3 patients caused by stent migration (n=2) and a problem with the introducing system. Dysphagia improved to the same extent in both patient groups from a median of 3 (liquids only) to 1 (eat some solid food). Reflux symptoms were reported by 3/12 (25%) patients with an anti-reflux stent and by 2/14 (14%) patients with an open stent. Esophageal acid exposure time was abnormal with both types of stents (mean 24-hr reflux time: anti-reflux stent (n=9): 25% vs. open stent (n=2): 10% (normal: <4%); p=NS). Increased esophageal reflux exposure was found in 6/9 patients with an anti-reflux stent and in 1/2 patients with an open stent. Major complications were the same in patients with anti-reflux stents or open stents, 3 (20%) in each group, consisting of bleeding (n=3), severe pain (n=2), and aspiration pneumonia (n=1). The main cause of recurrent dysphagia was stent migration in 7/30 (23%) patients. Conclusions: The FerX-Ella stent provides symptomatic relief against malignant dysphagia, however the design of the anti-reflux valve needs to be improved to prevent gastroesophageal reflux.

Esophageal Stenting

Malignant obstruction of the esophagus is a debilitating condition, with dysphagia as its main symptom. Many patients present with advanced disease and palliative treatment is the only possibility. Since their widespread introduction 10 years ago, self-expanding metal stents have become accepted as an extremely effective method of palliating malignant dysphagia. Early reports suggesting very low complications have been superseded by results from randomized trials. It is now evident that the complication rate is significant and the need for reintervention can be as high as 50%. Modifications in stent design should reduce this reintervention rate. There are a large number of stent designs now available and it is essential that the interventional radiologist understand the particular strengths and weaknesses of each design, so that the correct choice of stent can be made for a particular patient. The most recent designs include antireflux stents and removable stents. Both represent significant advances and should reduce stent-related complications.

Antireflux stents in tumors of the cardia

Self-expanding metal esophageal stents (SMES) are highly effective in relieving dysphagia in patients with esophageal carcinoma. As the incidence of cancer at the lower esophagus/cardia continues to increase, SMES also are being deployed across the gastroesophageal junction (GEJ). However, use of SMES in this location makes the stomach and the esophagus, in effect, a common cavity, which predisposes patients to gastroesophageal reflux (GER) and aspiration. Reflux may result from an increase in intra-abdominal pressure or it may occur passively when the patient is recumbent. Acid-suppression medications do not protect against regurgitation and aspiration. We developed a modified antireflux SMES and evaluated its efficacy in vitro, in dogs, and in 11 patients with distal esophageal/GEJ carcinoma. The modification involved extending the polyurethane coating of the stent to 8 cm below the lower edge. In dogs, significantly more reflux episodes occurred with the regular stent (mean, 197 episodes) than with the modified stent (mean, 16 episodes; P = 0.03). In patients who received the modified stent, dysphagia scores were significantly reduced (mean baseline score, 3.4; mean end point score, 1.1; P <0.001). The modified stent prevented GER while allowing belching and vomiting.

Treatment of malignant esophageal/cardiac stricture with self-expanding antireflux metallic stents: A preliminary report from 17 patients

BACKGROUND: Different types of self-expanding metallic stents are available for the palliative treatment of malignant strictures at the gastroesophageal junction. To overcome some of the disadvantages in the design of these metallic stents, we designed a silicone-covered self-expanding antireflux metallic stent that can prevent free gastroesophageal reflux after stent placement. METHODS: Seventeen silicone-covered antireflux prototypes were used in 17 patients with dysphagia caused by inoperable malignant tumors involving the gastroesophageal junction. RESULTS: Stent implantation was technically successful in all 17 patients. There were no procedure-related perforations or deaths. As a group, the mean dysphagia grade improved significantly (2.56 ± 0.49 vs 1.00 ± 0.51, P < 0.001) and the mean lumenal diameter was greatly increased (4.11 ± 1.02 vs 14.72 ± 4.01, P < 0.001) after stent placement. Ten patients received ambulatory 24-h esophageal pH monitoring and compared with the healthy volunteers, there were no postprocedural abnormal gastroesophageal refluxes in any patient. Three patients had substantial chest pain requiring long-term analgesics. No other complications were observed. CONCLUSIONS: The newly developed self-expanding antireflux metallic stent is safe and effective for use in the palliation of dysphagia caused by malignant strictures at the gastroesophageal junction. A larger patient population would be required to give valid conclusions.

Drainage and Reflux Characteristics of Antireflux Ureteral Double-J Stents*

We tested three antireflux double-J stents and compared them with common double-J stents in ex vivo canine urinary systems. At a physiologic flow rate, the drainage function of the antireflux stents proved to be sufficient; however, at a supraphysiological flow rate, drainage was inferior to that of the common double-J stent. Our reflux study demonstrated high-grade reflux with the common double-J stent, which transmitted more than 90% of the bladder pressure to the renal pelvis. The antireflux stents prevented this to a certain degree by both a reduction in and a delay of pressure transmission to the renal pelvis. In preliminary clinical trials, vesicorenal reflux was not detectable radiologically with the antireflux stents.