347e: Temporary Placement of Covered Self-Expandable Metal Stents (CSEMS) in Benign Biliary Strictures (BBS): Eight Years of Experience

Abstract

Introduction: Benign biliary strictures (BBS) have been endoscopically managed with placement of multiple plastic stents. Uncovered metal stents have been associated with mucosal hyperplasia and long term data on covered self-expandable metal stents (CSEMS) are still lacking in BBS. We report the efficacy and complication rates of CSEMS in the treatment of BBS. Methods: One-hundred twenty-one patients (78 men, 64%) with BBS had placement of CSEMS between January 2002 and August 2008 and removal between November 2002 and December 2008. Fifty-five (45%) received Viabil stents (Conmed) and 66 (55%) received Wallstents (Boston Scientific). Etiologies of BBS included: chronic pancreatitis (CP) (n=48), gallstone disease (n=34), post liver transplant (n=34), and inflammatory conditions (PSC and autoimmune pancreatitis) (n=5). Efficacy and safety were evaluated retrospectively. Patients were considered to have resolution if they had evidence of stricture resolution on cholangiogram at removal of CSEMS and did not require further biliary stenting during follow-up. Results: One-hundred twenty-one patients (mean age 54.6 ± 14.0 years) had CSEMS placed for a mean stent time of 164.6 ± 202.3 days and a mean follow-up time of 734.6 ± 576.8 days. Seventy-six (63%) had resolution of BBS. For those with BBS related to chronic pancreatitis (n=48), only 24 (50%) had resolution whereas all other etiologies of BBS had resolution in 52/73 (71%)(p=0.02). Complications during placement of CSEMS were observed in 24 patients (20%) including pain (n=13), post-ERCP pancreatitis (n=9), and bleeding (n=2). Complications during stent removal occurred in 15 (12%) patients including post-ERCP pancreatitis (n=4), pain (n=4), stent unraveling (n=4), bile duct leak (n=1), bleeding (n=1) and bacteremia (n=1). Cholangitis was suspected in six patients on removal (5 Viabil, 1 Wallstent). Stent migration occurred in 19 patients (16%) with four migrations in the Viabil group and 15 in the Wallstent group. Intimal hyperplasia occurred in 7 patients (6%) and stent embedment into the mucosa (biliary or ampullary) occurred in 7 (6%), all of whom had Wallstents. Conclusion: Temporary placement of CSEMS for BBS may offer an alternative to plastic stenting in cases not related to chronic pancreatitis. However, the significant complications and modest resolution rates limit our enthusiasm for use of these stents in benign biliary strictures.