Postoperative anastomotic bile duct strictures develop in 10-30% of patients post-liver transplant and are managed by serial endoscopic dilation and stenting, often requiring multiple procedures over a period of one year or longer. Although highly successful and with lower morbidity compared to surgical revision, the endoscopic approach involves the placement of multiple plastic stents (PS) across the stricture, serially upsizing every 3 months until the stricture has been fully dilated. This typically requires multiple procedures over a long duration, increasing health care expenditures while exposing the patient to the risks of multiple interventions and inconvenience. Newer, fully coated, self-expandable metallic stents (cSEMS) may allow endoscopic treatment of these strictures while requiring less time and significantly fewer procedures to do so. With more than 6,000 liver transplants performed in the U.S. each year and health care expenditures outpacing inflation, there is a critical need to identify a more cost effective approach to the treatment of post-transplant anastomotic strictures. We propose conducting a randomized pilot study to compare cSEMS with plastic stents (the current standard of care) for the first-line treatment of post-liver transplant bile duct strictures. We will enroll patients with anastomotic, post-orthotopic liver transplant bile duct strictures since these represent the majority of benign, postoperative bile duct strictures. Patients in the PS group will undergo sequential dilation and stent upsizing at 3 month intervals until the stricture has resolved (standard of care). Patients in the cSEMS group will undergo initial placement of a cSEMS and return after six months;at that time, the cSEMS will be removed and only replaced for an additional six months if the stricture has not resolved. The superior patency of cSEMS compared to PS allows for a longer stenting interval between procedures. Stricture resolution will be defined as the absence of clinical signs or symptoms to suggest biliary obstruction and a residual duct diameter of >75% of the proximal and distal duct. We will measure stricture resolution at 6 months (our primary outcome in this pilot study), after no more than 12 months of continuous stent therapy, and persistent resolution after one year of post-stenting follow-up.
The current standard of care for post-liver transplant bile duct strictures involves serial placement of multiple plastic stents under endoscopic and fluoroscopic guidance to progressively dilate or stretch it open. This approach necessitates multiple procedures which may extend over one year before the stricture is adequately dilated. We propose a pilot study comparing the standard approach of plastic stenting with the use of newer, fully coated metallic stents which are self-expandable, thereby permitting successful dilation of benign bile duct strictures with fewer procedures over a shorter time.