Paclitaxel-eluting covered metal stents versus covered metal stents for distal malignant biliary obstruction: a prospective comparative pilot study

Abstract

In unresectable malignant biliary obstruction, stent insertion can be the treatment of choice. However, metal stents are susceptible to occlusion by tumor ingrowth or overgrowth. The recently introduced paclitaxel-eluting covered metal stents (PECMSs) may prevent occlusion from tumor ingrowth by the antitumor effect of paclitaxel. Our goal was to compare the efficacy and complication rates of PECMSs and the control covered metal stents (CCMSs) in patients with malignant biliary obstruction. Prospective, randomized pilot study. Single tertiary referral center. From November 2006 to June 2008, 52 patients with unresectable distal malignant biliary obstruction were enrolled. A PECMS was inserted in 26 patients and a CCMS in 26 patients. Of these patients, 2 patients in the PECMS group and 1 patient in the CCMS group were excluded. Finally 49 patients (24 patients in the PECMS group and 25 patients in the CCMS group) were included in the analysis. PECMSs and CCMSs were inserted by using the standard ERCP technique. The mean follow-up period was 194.0 ± 144.2 days in the PECMS group and 238.8 ± 147.4 days in the CCMS group (P = .287). The stent patency duration and survival time were not significantly different between the 2 groups (P = .307 and P = .596, respectively). Stent occlusion caused by tumor ingrowth occurred in 5 patients in the PECMS group. In the CCMS group, stent occlusion caused by tumor ingrowth (n = 4) or distal stent migration (n = 4) occurred in 8 patients. In the PECMS group, 3 cases of transient cholangitis-like symptoms without stent occlusion and 1 case of pancreatitis occurred after stent insertion. One patient in the CCMS group experienced pancreatitis. This study was a pilot study in which no power calculation was done. It was performed at a single center and was performed in a nonblinded fashion. PECMSs may be safe with acceptable complication rates. There were no significant differences in the duration of stent patency and patient survival time between PECMSs and CCMSs in patients with distal malignant biliary obstruction. However, a larger study powered to detect differences must be done to conclude that there is any benefit of PECMSs.