When is placement of a self‑expanding metal stent (SEMS) reasonable in gastroenterology?

When is SEMS Placement Reasonable in Gastroenterology?

SEMS placement is reasonable in gastroenterology for malignant alimentary tract obstructions, with specific indications varying by anatomic location: it should be avoided in resectable esophageal cancer, considered for palliative esophageal obstruction, used selectively for gastric outlet obstruction when surgery is not feasible, and employed as bridge-to-surgery or palliation in malignant colonic obstruction. 1

Esophageal and Gastric Cardia Obstruction

Resectable Disease - AVOID SEMS

• Do NOT routinely place SEMS in patients with potentially resectable esophageal cancer without multidisciplinary review 1
• Evidence shows SEMS as bridge-to-surgery results in:
  • Higher mortality and morbidity 1
  • Lower R0 resection rates 1
  • Stent migration in 29.9% of cases 1
  • 10% 30-day mortality in some series 1
• For nutritional support in resectable cases, use enteral feeding tubes (nasogastric or percutaneous) instead 1
  • Be aware of potential abdominal wall tumor seeding with PEG placement 1
  • PEG can complicate subsequent gastric conduit formation 1

Non-Resectable Disease - SEMS is Reasonable

• SEMS placement is appropriate for palliation in non-resectable esophageal cancer 1
• Brachytherapy is equally effective and can be used alone or combined with SEMS 1
• Do NOT use laser therapy or photodynamic therapy - inferior outcomes compared to SEMS 1

Technical Specifications for Esophageal SEMS

• Use fully covered (FCSEMS) or partially covered SEMS (PCSEMS), NOT uncovered stents 1
• Uncovered stents have higher rates of tumor ingrowth and need for re-intervention 1
• Consider stent-anchoring/fixation methods to reduce migration risk 1
• Endoscopic suturing or over-the-scope clips effectively reduce migration 1
• Use larger diameter stents (20-23mm) when crossing the gastroesophageal junction to prevent migration 1

Gastric Outlet Obstruction (GOO)

When Surgery is Preferred

• For patients with life expectancy >2 months, good functional status, and surgical fitness, surgical gastrojejunostomy should be considered first 1
• Laparoscopic approach preferred over open (lower blood loss, shorter hospital stay) 1

When SEMS is Reasonable

• SEMS is appropriate when patients are NOT candidates for gastrojejunostomy (surgical or EUS-guided) 1
• SEMS allows earlier oral intake but has shorter durability than surgical bypass 1
• EUS-guided gastrojejunostomy is an acceptable alternative if endoscopist is experienced 1

Contraindications for GOO SEMS

• Do NOT use enteral stents in patients with:
  • Multiple luminal obstructions 1
  • Severely impaired gastric motility 1
• Consider venting gastrostomy instead in these scenarios 1

Malignant Colonic Obstruction

Bridge-to-Surgery (Resectable Disease)

• SEMS is a reasonable choice as bridge-to-surgery for left-sided malignant colonic obstruction 1
• Benefits include:
  • Higher rates of primary anastomosis 1
  • Lower rates of permanent stoma 1, 2
  • Allows elective one-stage surgery 1
  • Technical success rate 91.9-98% 1
• Critical caveat: Perforation during SEMS placement carries odds ratio of 46 for subsequent metastatic seeding 1
• Consider SEMS particularly for high-risk surgical candidates (ASA ≥III, age >70 years) 3

Palliative Setting (Non-Resectable Disease)

• SEMS is the preferred option for left-sided malignant colonic obstruction in non-resectable patients 1
• Alternative is diverting colostomy - choice depends on patient goals and functional status 1
• SEMS advantages:
  • Earlier oral intake 1
  • Shorter hospital stay 1
  • Avoids stoma 1
• For ECOG 0-1 patients, palliative surgery may offer better overall survival 1
• For ECOG 2-3 patients, no survival difference between SEMS and surgery 1

Right-Sided (Proximal) Colonic Obstruction

• SEMS is reasonable for proximal malignant obstructions, both as bridge-to-surgery and palliatively 1
• Despite technical challenges, studies show high success rates with minimal adverse events 1
• Associated with lower mortality, morbidity, and permanent stoma rates compared to emergency surgery 1

Extracolonic Malignancy

• SEMS placement is a reasonable alternative for extracolonic malignancy causing colonic obstruction when surgery is not an option 1
• Important caveats:
  • More technically challenging 1
  • More variable clinical success rates 1
  • Higher complication rates including stent migration 1
• Obstruction mechanism differs (extrinsic compression, mesenteric infiltration, dysmotility vs. space-occupying growth) 1

Critical Contraindications and Warnings

Absolute Contraindications

• Do NOT use SEMS in patients on or planned for antiangiogenic drugs (e.g., bevacizumab) 3
• Avoid in patients with signs of perforation 3

Multidisciplinary Approach Required

• All decisions should be made in multidisciplinary setting including oncologists, surgeons, and endoscopists 1
• Consider: obstruction characteristics, patient expectations, prognosis, subsequent therapies, and functional status 1

Biliary SEMS (Additional Context)

• For distal malignant biliary obstruction, fully covered SEMS preferred over uncovered 4
• FCSEMS have lower adverse event rates, longer patency, and lower reintervention rates 4
• Higher migration risk with FCSEMS but overall superior outcomes 4