Comparison of different types of covered self-expandable metal stents for malignant colorectal obstruction.

BACKGROUND: Stent migration is one of the main drawbacks of covered self-expandable metal stent (SEMSs), occurring in up to 40% of malignant colorectal obstruction management cases. Various types of covered SEMSs have been developed to reduce this risk. We aimed to compare the effectiveness and complication rates of the flare-type covered SEMS (Flare) with those of the double-layered covered SEMS (ComVi). METHODS: We performed a prospective, randomized study in four tertiary referral centers between July 2016 and April 2018. Patients with malignant colorectal obstruction were eligible for the study. The primary outcome was migration rate as observed within the first month. Rates of technical success, clinical success, and complications within the first month were also assessed. RESULTS: A total of 60 patients were included (mean age, 70.5 ± 12.5 years; male, 31 [51.7%]). Flare and ComVi stents were applied in 30 patients each. The Flare and ComVi groups showed comparable technical success rates (90% [27/30] vs. 96.7% [29/30], p = 0.605) and clinical success rates (85.2% [23/27] vs. 75.9% [22/29], p = 0.589). Migration occurred in three (11.1%) and four (13.8%) cases in the Flare and ComVi groups, respectively, without significant difference (p = 0.99), and the risk of other complications, including perforation and re-obstruction, did not differ between the two groups. CONCLUSIONS: Our study indicates that both flare-shape and double-layered covered SEMSs are equally effective options for the management of malignant colorectal obstruction with low migration rates when compared with previously reported migration risk of covered SEMS.

Use of esophageal small balloon or papillary sphincter knife in the treatment of stent implantation for colorectal malignant obstruction / 中南大学学报(医学版)

Objective:To explore the function of esophageal small balloon or papillary sphincter knife in the treatment of stent implantation for colorectal malignant obstruction,and to improve the success rate of colonic stent placement in such patients.Methods:A total of 49 patients with colorectal cancer complicated with almost complete obstruction or colorectal cancer were enrolled for this study.The esophageal small balloon or papillary sphincter knife was used in the guide wires.The guide wires gradually crossed the tumor gap and they were placed in the contralateral intestinal cavity with balloon progression.X-ray was then used to confirm whether the guide wire was inserted in the lesion intestinal cavity,and then the metal bare stent was inserted.Results:The guide wires was successfully inserted with conventional methods in these 49 cases,while they were also successfully placed the guide wire and the stent in the new way.Conclusion:For the patients with colorectal cancer complicated with complete obstruction or colorectal cancer located in obviously angled location,the use of esophageal small balloon or papillary sphincter knife can help the guide wire insert.They greatly improve the success rate of stent implantation.