Stents in cancer patients are used to hold open passageways that a tumor has narrowed or blocked. Cancer can compress or grow into the tubes that carry food, air, bile, urine, and stool through the body, and a stent (a small, hollow tube made of metal mesh or silicone) restores flow through that passage without major surgery. Stents are placed in the esophagus, bile ducts, colon, airways, and ureters, depending on where the obstruction occurs.
Some stents are permanent, used to manage symptoms for the rest of a patient’s life. Others are temporary, buying time so the body can stabilize before a planned surgery. Understanding which type applies depends on the location of the blockage and whether the cancer is curable.
How Tumors Create Blockages
Tumors obstruct the body’s passageways in two ways. They can grow directly into a tube’s lining, physically filling the space inside. Or they can press inward from the outside, squeezing the tube shut like a fist around a garden hose. Either way, the result is the same: whatever normally flows through that passage, whether food, bile, air, or urine, gets partially or completely blocked. The backup causes symptoms that range from uncomfortable to life-threatening, depending on the organ involved.
Stents work against both types of obstruction. The tube is guided into position through an endoscope, catheter, or bronchoscope, then expanded against the walls of the passage to hold it open. Most cancer stents are self-expanding metal mesh tubes that spring open on their own once released from their delivery device.
Colon and Rectal Stents
Colorectal cancer, metastatic cancer that has spread to the abdomen, and locally advanced pelvic tumors can all block the colon. When a tumor obstructs the large intestine, stool cannot pass, causing severe pain, vomiting, and dangerous distension of the bowel.
Colonic stents serve two distinct roles. The first is palliation: for patients who cannot undergo curative surgery, a stent relieves the blockage permanently and avoids the need for an emergency colostomy bag. The second is called “bridge to surgery,” where the stent decompresses the bowel temporarily so the patient can be stabilized and prepared for a planned operation under safer conditions. In the bridge-to-surgery approach, the median time from stent placement to surgery is about 15 days, giving the bowel time to recover and the surgical team time to plan.
European clinical guidelines now recommend self-expanding metal stents for both curative and palliative settings in patients with left-sided colon obstruction, and multiple professional societies endorse their use as a bridge to surgery when the cancer is potentially curable. The guidelines have also expanded to include stenting for obstructions caused by cancers originating outside the colon that press on the bowel from the outside.
Esophageal Stents
When esophageal cancer or a tumor near the junction of the stomach narrows the swallowing passage, patients lose the ability to eat solid food and sometimes liquids. An esophageal stent props the passage open so food and drink can reach the stomach again. This is one of the most common palliative uses of stenting in cancer care, since advanced esophageal cancer is often inoperable by the time swallowing becomes severely impaired.
Esophageal stents can shift out of position over time. Fully covered metal stents in malignant strictures have a total migration rate of about 23%, though only around 12% of those migrations are clinically significant enough to require the stent to be replaced. Stent occlusion, where tumor tissue regrows through or around the stent, is less common but also requires replacement when it occurs.
Bile Duct Stents
Pancreatic cancer, bile duct cancer (cholangiocarcinoma), and gallbladder cancer frequently block the bile duct, the narrow tube that drains bile from the liver into the intestine. When bile cannot drain, it backs up into the bloodstream and causes jaundice: yellowing of the skin and eyes, intense itching, dark urine, and pale stools. Left untreated, the buildup leads to liver damage and infection.
A biliary stent restores bile flow and relieves jaundice, often within days. Both plastic and metal stents are used here, and the choice depends on the type and location of the blockage. Metal stents generally stay open longer. In patients with bile duct obstructions from pancreatic or biliary cancers, metal stents remain functional for a median of roughly 9 months without additional treatment. When radiation therapy is also given, that window extends to nearly 18 months. Plastic stents are cheaper but clog more quickly and may need to be swapped out every few months.
For tumors higher up in the bile duct system, where the ducts branch inside the liver, stent placement becomes technically more challenging. Success rates with plastic stents in these locations can drop to around 81%, with higher rates of infection and blockage compared to simpler, lower obstructions.
Airway Stents
Lung cancer and cancers that metastasize to the chest can narrow or collapse the trachea or bronchial tubes. The main symptoms are progressive shortness of breath and cough, which worsen as the airway closes. When a tumor blocks enough of the airway, it becomes a medical emergency.
Airway stents come in two main types. Metal mesh stents were originally designed for both tumors growing inside the airway and those pressing in from outside. They work well for external compression, but tumors inside the airway can grow through the gaps in the metal mesh, re-blocking the passage and making it difficult to place a second stent. Silicone stents cause less tissue irritation and are easier to remove or reposition, which makes them a better fit when stent adjustment is likely. Patients with external compression consistently show marked improvement in breathing after stent placement.
Ureteral Stents
Cervical, bladder, prostate, and other pelvic cancers can squeeze the ureters, the thin tubes that carry urine from the kidneys to the bladder. When a ureter is blocked, urine backs up into the kidney. If both sides are affected, kidney function deteriorates rapidly, and without intervention, the resulting buildup of waste products in the blood (uremia) is fatal.
An internal ureteral stent is a thin, flexible tube threaded up through the bladder into the blocked ureter. It holds the passage open so urine drains normally. Research shows that kidney filtration rates stabilize after stenting and remain stable over time, provided the stent is maintained. The key is timing: if stenting is performed before kidney function has significantly declined, that function can be preserved. If the kidneys have already sustained major damage, recovery is limited. These stents need to be exchanged periodically, typically every three to six months, because they can become encrusted or blocked.
Palliative vs. Bridge to Surgery
The distinction between these two uses matters because it shapes what happens next. A palliative stent is the primary treatment. It stays in place for the remainder of the patient’s life and is meant to control symptoms, maintain nutrition, preserve organ function, or simply improve comfort. A bridge-to-surgery stent is temporary, placed to stabilize a patient who is too sick for an immediate operation so that a planned, safer surgery can happen days or weeks later.
In palliative care, the goal is quality of life. A patient with an inoperable tumor blocking the esophagus gets a stent so they can eat. A patient with advanced colon cancer gets a stent so they can avoid a colostomy. In the bridge-to-surgery setting, the stent converts an emergency into an elective procedure, which consistently leads to better surgical outcomes, lower complication rates, and a higher chance of completing the operation in a single step rather than requiring a temporary stoma.
What the Procedure Feels Like
Most cancer stent placements are minimally invasive. Depending on the location, the stent is delivered through an endoscope (for the esophagus, bile duct, or colon), a bronchoscope (for the airways), or a catheter guided by imaging (for the ureters). General anesthesia is sometimes used, but many placements require only sedation. The procedure itself typically takes under an hour.
Recovery is fast compared to open surgery. Most patients resume normal activity within a few days to a week. You may feel pressure, mild pain, or an unusual sensation at the stent site for the first day or two. Colon stents can cause cramping as the bowel adjusts. Airway stents sometimes trigger coughing. Ureteral stents are known for causing a persistent urge to urinate and mild flank discomfort, which tends to ease over the first week but may not fully resolve while the stent is in place.
How Long Stents Last
Stent longevity varies by location, stent material, and whether the patient is also receiving cancer treatment like radiation or chemotherapy. Biliary metal stents, for example, stay open for a median of about 9 months on their own, but concurrent radiation therapy can nearly double that to around 18 months. Colonic stents used for palliation can remain functional for months, though tumor regrowth or stent migration may eventually require replacement.
The most common reasons a stent fails are tumor ingrowth (cancer growing through the mesh), tumor overgrowth (cancer growing over the ends of the stent), migration (the stent shifting out of position), and encrustation or debris buildup. When a stent fails, it can usually be replaced or a second stent can be placed inside the first. Your care team will monitor for signs of re-obstruction, which vary by location but generally involve the return of the original symptoms: difficulty swallowing, jaundice, bowel obstruction, breathing trouble, or decreased urine output.