What is a Luminal Stent?
Stents are devices that create space when a duct or vessel has become obstructed. An enteral stent is a type of stent that is inserted in the digestive tract if a patient has a growth creating an obstruction in the esophagus, stomach, small intestine, or colon.
Rigid plastic stents were the only type of stents available until the 1990s, and complication rates were significant. Now, there are self-expandable metal stents (SEMS), self-expandable plastic stents (SEPS), and biodegradable stents.
The enteral stent is a self-expandable metal stent. SEMSs are made of woven, knitted, or laser-cut metal mesh cylinders that exert self-expansive forces until they reach their maximum diameter. Both ends of the SEMSs are flared to prevent movement after they have been placed. They are packaged in a compressed form and are contained in a delivery device. Some SEMSs are covered or partially covered by plastic or silicone to prevent the tumor from growing into the mesh, but enteral stents are currently manufactured uncovered.
Why is a Luminal Stent Placed?
If the setting of a growth (i.e. tumor, cancer) is causing a blockage somewhere in the gastrointestinal tract, a doctor may suggest an enteral stent for two reasons:
- Palliative care—Enteral stents are often used to treat malignant obstructions. In advanced colorectal disease or esophageal cancer, doctors may recommend a stent when surgery, chemotherapy, and radiation are no longer the best options. In patients with esophageal cancer, stenting provides relief of dysphagia (difficulty swallowing) in 95 percent of patients. For patients with colorectal cancer, enteral stents create space in an obstructed bowel so that stool can pass. The goals of stents in palliative care are management of symptoms and improved quality of life.
- Preoperative decompression—Enteral stents can also be used as a temporary treatment to alleviate a blockage in the colon. Often, an obstruction in the colon would require immediate surgery, but a stent could convert an emergency procedure into an elective procedure and could prevent the need for a colostomy. If you are at increased risk for complications as a result of emergency surgery, an enteral stent could be the preferred method of treatment for you. Studies have shown that colonic stent insertion followed by elective surgery is more effective and less costly than emergency surgery.
The use of enteral stents has expanded to the treatment of benign digestive conditions as well, such as strictures, bleeding varices, and fistulas in the gastrointestinal tract.
What are the Risks Associated With a Luminal Stent?
Initial risk factors of enteral stents may include:
- Tracheal compression
Later complications may include:
- Stent migration
- Tumor ingrowth
Enteral stents are a successful solution for palliative care in cancer patients and preoperative decompression for individuals who would otherwise need emergency surgery. Stenting has been proven to be safe and successful for all age ranges and has expanded into the realm of benign strictures. It is certain to expand further as biodegradable stents and drug-eluting stents are studied and developed.