Small‐Bowel Impaction Caused by Mechanical Interlocking Between Duodenal Metal and Biliary Plastic Stents

Duodenal self‐expandable metal stents (SEMS) are widely used to treat malignant gastric outlet obstruction (GOO). However, stent migration is a well‐known complication. We report a rare case of small‐bowel impaction caused by the migration of a duodenal SEMS with a biliary plastic stent (PS). A 78‐year‐old woman with pancreatic head cancer underwent biliary PS and duodenal SEMS placement for obstructive jaundice and GOO. At 4 months after initiating neoadjuvant chemotherapy, computed tomography revealed tumor shrinkage and improvement in duodenal stenosis; however, the SEMS and PS had migrated to the ileum. Double‐balloon enteroscopy was attempted; however, stent removal was unsuccessful because of mechanical interlocking and impaction. Therefore, a partial ileal resection was performed. Histopathological examination revealed transmural infiltration of inflammatory cells and abscess formation. If a duodenal SEMS migrates with a biliary PS, mechanical interlocking may occur, resulting in small‐bowel impaction. Clinicians should be aware of this rare complication and should consider careful follow‐up and timely intervention if stent migration is detected. Trial Registration : N/A