SAN FRANCISCO—A novel small-caliber metal stent can provide a low-risk means of palliation for severe malignant dysphagia, according to investigators who have created these stents and are now testing them in trials. The results were presented at the 2011 Gastrointestinal Cancers Symposium by Stephen Kucera, MD, of H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida, where he is an interventional endoscopy fellow.
Self-expandable covered metal stents are an important component of palliative care for malignant dysphagia, but significant complication rates have been associated with large-diameter stents, Kucera noted.
“We hypothesized that small-caliber, fully covered self-expandable metal stents (sccSEMS) would provide adequate palliation of dysphagia but carry less risk for major complications,” he said at a poster session.
He and his colleagues conducted a prospective observational study of … patients presenting with severe malignant dysphagia between December 2008 and August 2010. They placed 38 sccSEMS in 23 patients with esophageal cancer. The prestent luminal diameter was <8 mm in 187 patients and 8 to 10 mm in 5 patients. All stents were placed under direct endoscopic vision without fluoroscopy. Dysphagia scores, migration rates, and complication rates were recorded.
sccSEMS are made of nitinol (nickel titanium). Their shaft diameter varies depending on the placement location: 12 to 16 mm for esophageal placement, 14 to 16 mm for tracheal-bronchial placement, and 8 to10 mm for biliary placement.
“One of the problems with our current stents is the shaft diameter,” he said. “The smallest we have is 20 mm. It makes no sense to put something this size when there is a residual luminal diameter of 8 mm, for example, because you can get fistulas, perforations, bleeding, and severe chest pain. This often means we have to remove the stents.”
Efficacy of Novel Stents
The poststent median dysphagia score decreased from 3 to 2 (P <.0001). Median duration of first stent placement was 71 days (range, 7-139). The overall migration rate was 31.6%, most of which was anticipated because of chemotherapy or radiotherapy; for only 2 patients did migration occur in the absence of treatment.
He acknowledged these small stents “may migrate more,” but noted that they are small and easy to remove. “We were able to remove all the migrated stents endoscopically without complication,” Kucera reported. “We will accept more migration at the expense of less complications and pain.”
Complications included chest pain in 3 (7.9%) patients. No major complications occurred.
The Alimaxx-ES stents are being manufactured by Merit Medical. Dr. Kucera reported no relevant conflicts of interest.