A pilot study showcasing the difficulties in endoscopic biliary drainage using uncovered self-expanding metal stents for resectable perihilar cholangiocarcinoma

Background: Endoscopic retrograde cholangio-pancreatography (ERCP) with plastic stent placement is the standard pertaining preoperative biliary drainage for resectable perihilar cholangiocarcinoma (pCCA). Uncovered self-expanding metal stents (ucSEMS) have shown better outcomes in palliative settings. This pilot study aimed to assess the feasibility and safety of direct ucSEMS placement via ERCP for resectable pCCA. Materials and methods: In this single-centre pilot study, ten patients with presumed resectable pCCA (without prior drainage) underwent ERCP aiming to place an ucSEMS directly across the papilla into the future liver remnant (FLR). If the opposing liver segment was cannulated or had contrast injected, a stent was placed here too. Primary outcome was feasibility, defined as ucSEMS placement in the targeted liver segment without the need for additional drainage, with adequate bilirubin decrease according to the TOKYO criteria. Secondary outcomes included ERCP adverse events (AE) and successful stent removal during surgery. Results: In 5 of the 10 included patients, direct ucSEMS placement in the FLR was technically successful, but one required additional intervention, resulting in 40% feasibility. All patients experienced ERCP-AE (five mild, five severe). Only two patients underwent hepatectomy, one after unsuccessful ERCP and one with successful ucSEMS removal during hepatectomy. Other patients did not proceed to hepatectomy due to ERCP-related AE (n = 3), disease progression (n = 2), or unresectability upon staging (n = 3). Conclusion: Direct placement of ucSEMS for resectable pCCA showed limited feasibility and high AE rates. Its routine use is not justified without further refinement and larger studies to reduce AE and improve outcomes.