Fig. 1. Number and details of duodenal stent placement cases from January 2014 to December 2016. The bold boxes indicate the cases included in the study. cSEMS, covered self-expandable metal stent; ucSEMS, uncovered self-expandable metal stent.

Fig. 2. Types of duodenal stenosis due to tumor. Type I: Stenosis occurring at the level of the duodenal bulb or upper duodenal genu, but without papillary involvement (see light blue marker area). Type II: Stenosis affecting the second part of the duodenum and involving the papilla (pink marker). Type III: Stenosis affecting the third part of the duodenum distal to the papilla, without involvement of the papilla (yellow marker area).

Fig. 3. Nitinol-covered self-expandable metal stent (Niti-S Combi gastroduodenal stent; Taewoong Medical).

Fig. 4. Schematic outline of stent placement in a side-by-side position. We positioned the biliary and duodenal stents next to each other to avoid any interference.

Fig. 5. Patient 1: Simultaneous placement of biliary and duodenal stents. (A) X-ray showing the simultaneous placement of biliary and duodenal stents. (B) Endoscopic image showing stenosis and bleeding in the duodenum immediately after the stent placement.

Graphical abstract