Clinical Experience With A Nitinol Self-Expanding Colonic Stent - Data From The Wallflex-Er Colonic International Registry

Background: Self expanding metal stents (SEMS) have been suggested as an alternative to surgery for malignant large bowel obstruction, providing relief of obstruction and avoiding a stoma to palliate uncurable pts (PAL), or facilitating bowel decompression as a bridge to surgery for curable pts (BTS). Methods: An Internet-based multi-national registry is compiling data on colo-rectal stenting as practiced by surgeons and gastrointestinal endoscopists in academic and community based hospitals. Pts with colo-rectal obstructions produced by malignant neoplasms received a WallFlex™ Colonic Stent (Boston Scientific, Natick, USA) in PAL and BTS groups. 200 pts will be enrolled and followed to death (PAL) or surgery (BTS) or to retreatment or 12 mo, whichever comes first. To date 82 pts have complete data. Enrollment still ongoing. Primary endpoint is relief of obstruction and stent patency allowing adequate intestinal tract transit. Other endpoints include technical success, complications, and survival. Results: 82 pts, 60 PAL and 22 BTS, received a total of 87 stents. Technical success defined as adequate stent placement and expansion, was achieved in 73/82 (89%). Failure due to poor stent placement (6), poor expansion (2) or both (1). Clinical success, defined as improvement in passage of stool without the need for reintervention from baseline to surgery (BTS) or 30 d (PAL), was achieved in 75/82 (91%). Failures due to colonic perforation (3), stent migration (2) and reobstruction (2). Tumors were 91% intrinsic. Incidence of 6 clinical symptoms of obstruction improved from a mean of 67 ± 29% at baseline to 14 ± 11% at 30 d. Procedural complications associated with stent placement (up to 6 hrs of stenting) occurred in 3 pts: colon perforation (2), pain (1). Post-procedure complications between stent placement and surgery (BTS) or 30 d follow-up (PAL) occurred in 11 pts: reobstruction due to fecal impaction (1), stent migration (3), colon perforation (1), bowel impaction into stent (1), small bowel subileus (1), stent deployment failure (1), coma (1), pain (2). Pre-stenting dilation was performed in all cases of perforation. The mean time between stent placement and surgery was 25 d (range 3-93). Conclusion: This interim report reflects the first prospective international registry on utility of colonic stenting per local standards of practice. It demonstrates that SEMS provide safe and highly successful treatment. Most BTS pts proceeded to one-step resection after prior decompression by SEMS placement. In most pts with uncurable colo-rectal cancer and obstructive symptoms SEMS provided a minimally invasive palliative alternative to surgery.