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

BACKGROUND: 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. OBJECTIVE: 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. DESIGN: This study was a prospective, single-arm, observational clinical study of patients enrolled between December 2005 and September 2010. SETTINGS: This study was conducted at a referral hospital in Japan. PATIENTS: Twenty-four consecutive patients with malignant colorectal obstruction were included in the study. INTERVENTIONS: A double-wire woven uncovered stent was placed by use of a standard through-the-scope endoscopic placement technique. MAIN OUTCOME MEASURES: Technical, initial clinical, and long-term clinical success were measured. Longterm clinical success was defined as sustained relief of obstructive symptoms without reintervention until the patient's death. RESULTS: 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). LIMITATIONS: This study was limited because it was a single-arm, single-center study, and it had a small sample size. CONCLUSIONS: Endoscopic placement of double-wire woven uncovered stents is effective and safe as definitive palliative treatment for patients with malignant colorectal obstruction.