EP493 - Beyond the Pancreas: Palliation of Malignant Small Bowel Obstruction with a Lumen-Apposing Metal Stent

Purpose/Background: A 58-year-old woman with advanced locoregional colorectal cancer, initially diagnosed in September 2024, presented one year later with a recurrent malignant small bowel obstruction. Her initial surgical history included an extended right hemicolectomy with gastric wedge resection, followed by a subsequent surgery for carcinomatosis causing obstruction of the anastomosis that resulted in re-resection and creation of an end ileostomy. Despite chemotherapy, her disease progressed, leading to a duodenal obstruction managed with a endoscopic ultrasound-guided gastrojejunostomy with a lumen apposing metal stent and percutaneous transhepatic biliary drainage. In September 2025, she represented with small bowel obstruction. CT scan identified a metastatic nodule at the abdominal fascia causing an obstruction of the ileostomy.

Methods/Interventions: After several days of nasogastric tube decompression, there was no return of bowel function and other interventions were explored. Venting gastrostomy tube was deemed technically unfeasible by gastroenterology (GI) and interventional radiology due to patient's anatomy. The patient wanted to avoid abdominal exploration, so in consultation with interventional GI a lumen-apposing metal stent (LAMS) was placed across the nearly obstructed ileum at the site of obstruction. The scope was introduced through the ileum where a 1 cm long 3 mm diameter luminal narrowing 3 cm proximal to the ileostomy stoma with proximal dilation of the ileum and retained stool was encountered . A 15 mm x 10 mm LAMS was deployed using fluoroscopic and endosopic guidance. The stent was dilated to 8 mm with resultant rush of stool through ileostomy.

Results/Outcomes: Diet was immediately advanced and she was tolerating a regular diet by postoperative day 1 with normalized ostomy output. She was discharged home soon after.

Conclusion/Discussion: Around 15% of patients with colorectal cancer will present with obstruction. If cancer is discovered in the early stages, surgical removal is the mainstay of treatment. However, there are times when patients are not operative candidates due to debility or advanced stage cancer. For this subset of patients, endoscopic stenting is an ideal option as a bridge to surgery or palliation.

LAMS are currently only FDA approved for transgastric or transduodenal endoscopic drainage of symptomatic pseudocyst and walled-off necrosis however their use has expanded in recent years. Typically, self-expanding metal stents (SEMS) have been used for bowel strictures, but LAMS have a unique bi-flanged design that lowers the risk of stent migration. Data on its use for intestinal strictures is sparse, but studies show a high technical and initial clinical success rate. It is important to note that LAMS use is limited to short strictures and although migration rates are low, studies show that rates can still be as high as 10.5%. Nevertheless, this case highlights an unique indication for LAMS placement for palliation in a patient with an extrinsic stricture causing malignant obstruction at the ileostomy site.

Intraoperative fluorscopy after stent placement.
Fluoroscopic image after the placement of lumen apposing metal stent in the ileum across the extrinsic stricture.
Admission CT
CT performed on initial presentation to the hospital showing metastic nodule causing an obstruction at the level of the fascia.