Covered Metallic Stents With an Anti-Migration Design vs. Uncovered Stents for the Palliation of Malignant Gastric Outlet Obstruction: A Multicenter, Randomized Trial

Abstract

OBJECTIVES:Previous studies reported comparable stent patency between covered self-expandable metallic stents (SEMS) and uncovered SEMS (UCS) for palliation of malignant gastric outlet obstruction (GOO). The aim of this study was to evaluate the efficacy and safety of the newly developed WAVE-covered SEMS (WCS), which has an anti-migration design, compared with UCS in gastric cancer patients with symptomatic GOO.METHODS:A total of 102 inoperable gastric cancer patients with symptomatic GOO were prospectively enrolled from five referral centers and randomized to undergo UCS or WCS placement. Stent patency and recurrence of obstructive symptoms were assessed at 8 weeks and 16 weeks after stent placement.RESULTS:At the 8-week follow-up, both stent patency rates (72.5% vs. 62.7%) and re-intervention rates (19.6% vs. 19.6%) were comparable between the WCS and the UCS groups. Both stent stenosis (2.4% vs. 8.1%) and migration rates (9.5% vs. 5.4%) were comparable between WCS and UCS groups. At the 16-week follow-up, however, the WCS group had a significantly higher stent patency rate than the UCS group (68.6% vs. 41.2%). Re-intervention rates in the WCS and UCS groups were 23.5% and 39.2%, respectively. Compared with the UCS group, the WCS group had a significantly lower stent restenosis rate (7.1% vs. 37.8%) and a comparable migration rate (9.5% vs. 5.4%). Overall stent patency was significantly longer in the WCS group than in the UCS group. No stent-associated significant adverse events occurred in either the WCS or UCS groups. In the multivariate analysis, WCS placement and chemotherapy were identified as independent predictors of 16-week stent patency.CONCLUSIONS:WCS group showed comparable migration rate and significantly more durable long-term stent patency compared with UCS group for the palliation of GOO in patients with inoperable gastric cancer.

Recent advancements in stent therapy in patients with malignant gastroduodenal outlet obstruction

“…On the other hand, the rate of tumor ingrowth or overgrowth in CMS was significantly lower than for UCMS in all reports shown in Table 2, which is an advantage of CMS. However, the rates of re-intervention and stent patency between CMS and UCMS were similar in these reports except for that of Lee et al (27). Lee et al reported that the CMS group had a significantly longer cumulative duration of stent patency compared with the UCMS group (27), though all patients undergoing deployment of SEMS had gastric cancer.…”

“…However, the rates of re-intervention and stent patency between CMS and UCMS were similar in these reports except for that of Lee et al (27). Lee et al reported that the CMS group had a significantly longer cumulative duration of stent patency compared with the UCMS group (27), though all patients undergoing deployment of SEMS had gastric cancer. Minata et al reviewed several studies about comparison between CMS and UCMS.…”

“…However, Maetani et al reported that there was no significant difference in the migration rate between CMS and UCMS because the 15-mm uncovered portion at both ends of the UCMS prevented stent migration (26). Lee et al also reported no significant difference in the migration rate between CMS and UCMS because of the anti-migration properties of CMS (27). On the other hand, the rate of tumor ingrowth or overgrowth in CMS was significantly lower than for UCMS in all reports shown in Table 2, which is an advantage of CMS.…”

“…Multivariate analysis revealed that the presence of a stent bridging the duodenal papilla [odds ratio (OR) =18.48; 95% CI, 2.298-148.48; P=0.006] was an independent predictor of acute pancreatitis. Table 2 shows the results of comparisons between CMS and UCMS in a prospective study and four randomized controlled trials (23)(24)(25)(26)(27). The technical and clinical success rates were similar between CMS and UCMS in all of these reports.…”

Partially-covered stent placement versus surgical gastrojejunostomy for the palliation of malignant gastroduodenal obstruction secondary to pancreatic cancer

“…Therefore, some authors have recommended concomitant biliary drainage before covered SEMS placement bridging the AOV [19,28]. However, several studies have shown that the risk of developing jaundice after SEMS placement is quite minimal (0-3.4%), irrespective of whether a bare or covered stent is used, most likely because the bile can drain through the space between the stent and the duodenal wall [29][30][31]; the rate of jaundice after SEMS placement in our present study was only 4.0%. In addition, a recent study has found that the bilirubin levels after covered SEMS placement bridging the AOV were similar between patients with and without prior or concomitant biliary drainage [32].…”