The aim is to compare percutaneous transhepatic biliary drainage (PTBD) with primary metal stent implantation (one stage-procedure) with PTBD with secondary metal stent implantation in terms of adverse events.

Percutaneous transhepatic biliary interventions (PBI) are used in biliary tract diseases when endoscopic access was not successful or not possible due to anatomical changes after abdominal surgery. Self-expandible metal stents (SEMS) can be applied percutaneously in patients with malignant extrahepatic bile duct obstruction. In this setting, PTBD is usually performed as a two step-procedure with primary drainage of the accumulated bile fluid by an external or an external/internal plastic stent and a secondary metal stent implantation at an interval of a few days. PTBD with primary metal stent implantation might shorten the hospital stay and is therefore equal to the increasingly used method of endoscopic ultrasound-guided biliary drainage (EUS-BD). EUS-BD offers a one step-procedure with primary metal stent implantation which is probably associated with lesser adverse events (AE) than PTBD with secondary metal stent implantation. However, it is not clear whether PTBD with primary metal stent implantation shows fewer adverse events than PTBD with secondary stent implantation. The aim of this study is to retrospectively analyze the prospectively collected data of PTBDs with primary or secondary metal stent implantation in patients with proximal and distal malignant bile duct obstruction. The focus of this single center study will be to compare the two approaches in terms of adverse events. Adverse events in PTBD might range from very mild to fatal. Therefore, the severity of the adverse events has been considered in the calculation.

Inclusion Criteria:

• PTBD with metal stent implantation into the extrahepatic bile duct
• malignant and non-resectable extrahepatic bile duct obstruction

Exclusion Criteria:

• benign extrahepatic bile duct obstruction