Favorable Long-term Clinical Outcome of Uncovered D-Weave Stent Placement as Definitive Palliative Treatment for Malignant Colorectal Obstruction

Abstract

Most self-expandable metallic stents for colorectal placement are uncovered because of the high migration rate of covered stents. However, the optimal stent design for colorectal use remains unclear. The purpose of this study was to evaluate the efficacy and safety of a double-wire woven uncovered stent for definitive palliative treatment of malignant colorectal obstruction. This study was a prospective, single-arm, observational clinical study of patients enrolled between December 2005 and September 2010. This study was conducted at a referral hospital in Japan. Twenty-four consecutive patients with malignant colorectal obstruction were included in the study. A double-wire woven uncovered stent was placed by use of a standard through-the-scope endoscopic placement technique. Technical, initial clinical, and long-term clinical success were measured. Long-term clinical success was defined as sustained relief of obstructive symptoms without reintervention until the patient's death. The Karnofsky performance status score before stent placement was 60 (median, interquartile range, 42.5-67.5). Twenty of 24 patients had primary colorectal cancer, and 4 had extracolorectal malignancies. The site of obstruction was the ascending colon in 10 patients, descending colon in 4 patients, sigmoid colon in 7 patients, and rectum in 3 patients. Technical, initial, and long-term clinical success rates were 100%, 100%, and 83%. Median stent patency time was 149 days (interquartile range, 45-198 days). Median survival time after stent placement was 155 days (interquartile range, 68-231 days). Four patients (17%) had negative outcomes including stent occlusion by tumor ingrowth (8%) and stent migration (8%). The highest Karnofsky performance status score after stent placement was 70 (median; interquartile range, 50-70). The Karnofsky performance status score improved after stent placement (p = 0.002). This study was limited because it was a single-arm, single-center study, and it had a small sample size. Endoscopic placement of double-wire woven uncovered stents is effective and safe as definitive palliative treatment for patients with malignant colorectal obstruction.