Update on the indications and use of colonic stents.

Self-expandable metal stent (SEMS) placement is a minimally invasive option for achieving acute colonic decompression in obstructed colorectal cancer. Colorectal stenting offers nonoperative, immediate, and effective colon decompression and allows bowel preparation for an elective oncologic resection. Patients who benefit the most are high-risk surgical patients and candidates for laparoscopic resection with complete obstruction, because emergency surgery can be avoided in more than 90% of patients. Colonic stent placement also offers effective palliation of malignant colonic obstruction, although it carries risks of delayed complications. When performed by experienced endoscopists, the technical success rate is high with a low procedural complication rate. Despite concerns of tumor seeding following endoscopic colorectal stent placement, no difference exists in oncologic long-term survival between patients who undergo stent placement followed by elective resection and those undergoing emergency bowel resection. Colorectal stents have also been used in selected patients with benign colonic strictures. Uncovered metal stents should be avoided in these patients, and fully covered stents are associated with high risk of migration. Patients with benign colonic stricture with acute colonic obstruction who are at high risk for emergency surgery can gain temporary relief of obstruction after SEMS placement; the stent can be removed en bloc with the colon specimen at surgery. This article reviews the techniques and indications of SEMS placement for benign and malignant colorectal obstructions.