Enteral stent placement for malignant afferent loop obstruction by the through-the-scope technique using a short-type single-balloon enteroscope

Background and study aims A short-type single-balloon enteroscope with a 3.2-mm working channel makes it possible to insert an enteral stent by the through-the-scope technique in patients with malignant afferent loop obstruction. Here, we report five cases of malignant afferent loop obstruction treated with endoscopic enteral stenting. We also propose a new classification for three types of malignant afferent loop obstruction. Type 1: The obstruction site is located distal to the papilla or the bilioenteric anastomosis. Type 2: The obstruction site is located at the papilla or the bilioenteric anastomosis. Type 3: The obstruction site is located between the bilioenteric and pancreaticoenteric anastomosis. The patients with type 1 and 3 were simply treated by inserting an enteral stent endoscopically. The patient with type 2 was treated with an endoscopic enteral stent for malignant afferent loop obstruction and with percutaneous transhepatic biliary stenting for malignant biliary obstruction. Although double stenting for type 2 remains a difficult endoscopic procedure, the endoscopic approach has become the standard approach for malignant afferent loop obstruction.