Boston’s WallFlex® Enteral Stents Gain Clinical Support


Boston Scientific Corporation has welcomed positive results from three studies of the WallFlex® Enteral Stent Systems, a family of self-expanding metal stents (SEMS) used to alleviate obstructive symptoms caused by cancers of the gastrointestinal tract. The studies, published in peer-reviewed medical journals, determined the WallFlex Stents to be safe and effective for the treatment of malignant colorectal and gastroduodenal obstruction.


WallFlex Enteral Stents are part of an advanced stenting system for the treatment of malignant colonic and duodenal obstruction. The braided structure provides flexibility to adapt to various anatomies while maintaining integrity of the lumen. Design features such as flared and looped ends reduce the risk of stent migration, while a variety of product lengths and sizes offer options for improved obstruction relief.

Study 1: 447 patients, prospective multi-centre study, palliative and bridge-to-surgery, safe and effective in malignant obstruction.

The first publication appeared in the October 2011 issue of Gastrointestinal Endoscopy, and reported the short-term safety and effectiveness of the Boston Scientific WallFlex Enteral Colonic Stent for relieving malignant colorectal obstruction. This 447-patient study represents the largest prospective, multi-center series to date of colonic SEMS placement in both palliative and bridge-to-surgery settings. The WallFlex Enteral Colonic Stent was determined to be safe and effective for treatment of malignant colorectal obstruction with a clinical success rate of 90.5 percent. The authors determined that SEMS allowed most bridge-to-surgery patients to have an elective surgical procedure without a colostomy and most incurable patients to receive minimally invasive palliation instead of surgery.

“Based on results from this study, physicians should consider SEMS as a first-line treatment option for patients with malignant colorectal obstruction,” said Soren Meisner, M.D., Bispebjerg Hospital, Copenhagen, Denmark and principal author of the study. “SEMS provide patients with a less-invasive alternative to surgery and may also improve quality of life.”

Study 2: 182 patients, 97.8% procedural, 94% clinical success as bridge to surgery

The second publication, appearing in the December 2011 issue of The American Journal of Gastroenterology, reports on 182 patients from the WallFlex Colonic Stent registries who received a WallFlex Colonic Stent as a bridge to surgery. Findings show rates of 97.8 percent procedural success and 94 percent clinical success, prompting the authors to conclude that the WallFlex Colonic Stent is both safe and effective as a bridge-to-surgery treatment in patients with acute malignant obstruction.

Study 3, Stent registry, 202 patients,  98% procedural, 91% clinical success, safe and effective duodenal stent.

Third, results from the international, multi-center WallFlex Duodenal Stent registry were published in the January 2012 issue of Digestive and Liver Disease. The largest prospective study of its kind assessed the treatment of malignant gastroduodenal obstruction in 202 patients. Results confirmed the safety and effectiveness of the WallFlex Enteral Duodenal Stent, which demonstrated procedural and clinical success rates of 98 and 91 percent respectively. The authors concluded that adoption of duodenal stenting could result in this minimally invasive procedure becoming standard of care when managing inoperable patients with advanced cancer experiencing gastric outlet obstruction.

Company comments

“Boston Scientific is focused on conducting research that has the potential to expand treatment options and improve patient care. Our Endoscopy group has invested millions of dollars over the past five years to conduct clinical trials involving nearly 1,400 patients at more than 110 medical centers in 21 countries,” said David Pierce, President of the Endoscopy Division at Boston Scientific. “We are honored to partner with worldwide experts in gastrointestinal endoscopy to design and conduct trials with high standards of quality and scientific rigor.”

Source: Boston Scientific