Outcome and safety of self-expandable metallic stents for malignant colon obstruction: A Korean multicenter randomized prospective study

Background: Newly developed uncovered stents are designed to have varied radial force and high conformability to improve clinical outcome and safety. This study aimed to determine and compare the clinical outcome and safety of the Taewoong D-type uncovered stent and the Boston Scientific Wallfex stent. Methods: Patients with acute malignant colonic obstruction were treated with a colonic stent. For the purpose of palliation, patients were randomly allocated. For the purpose of bridging, the type of stent was determined by the discretion of the individual doctors. Technical and clinical success and complication occurrence were measured as primary outcomes. Results: From 12 university hospitals, 123 patients with malignant colonic obstruction were enrolled. Of these 123 patients, 58 were treated with colonic stents for palliative purposes. The technical and clinical success rate was 100 % for both stents in the palliative group. Perforation occurred for one patient (3.6 %) in the Wallflex stent group (n = 28) on day 5 and for no patients in the D-type stent group (n = 30). Two cases of migration occurred: one with the Wallflex stent and one with the D-type stent. Stent restenosis occurred for one patient with the Wallflex stent. Preoperative bridging stents were placed in 65 patients. The median time to surgery was 10 days. The technical success rate was 93.4 %, and clinical success was achieved for 86.2 % of the patients. Perforation occurred for five patients: four with the Wallflex stent and one with the D-type stent. The efficacy and safety of the two stents did not differ statistically. Conclusions: The D-type colonic uncovered stent and the Wallflex colonic uncovered stent are effective and safe for both palliative and preoperative bridging therapy used to treat acute malignant colonic obstruction.