01Purpose and principlesWhat the treatment does and how it fits into care.
A self-expanding metal stent traverses a malignant narrowing and expands to restore a channel for intestinal contents. Its immediate success is mechanical, but its clinical purpose differs by treatment intent. As a bridge, it creates an opportunity to restore hydration and nutrition, complete staging and arrange planned oncological surgery. In palliation, the aim may be sustained symptom relief, oral intake, earlier discharge and avoidance of an operation or stoma. These are outcomes to verify, not automatic consequences of an apparently satisfactory deployment on fluoroscopy.
ESGE’s 2020 guidance supports discussing bridging stenting for potentially curable left-sided colon cancer and favours stenting for suitable palliative malignant obstruction. Most randomised evidence concerns the left colon and does not represent low rectal or proximal lesions equally. NICE also offers stenting or emergency surgery for potentially curative acute left-sided obstruction. This supports a shared decision, rather than a universal stent-first rule or an outdated prohibition of all bridging stents. Perforation risk, technical failure and uncertain individual oncological trade-offs must be weighed against the morbidity and stoma consequences of emergency surgery. The decision requires surgical backup and expertise, as well as an endoscope and a device.
Key points
- Reserve a colonic stent for symptomatic, radiologically confirmed malignant obstruction after assessment excludes perforation and other reasons for immediate surgery.
- Discuss bridging stenting alongside emergency resection for suitable potentially curable left-sided colon cancer; include perforation, failure, stoma and oncological trade-offs.
- Palliative stenting is often preferred for a suitable malignant obstruction, but new severe pain, guarding or shock after placement demands urgent assessment for perforation.
- Use an experienced operator with endoscopic and fluoroscopic competence; do not balloon-dilate a malignant stricture before or after deployment.
- Proximal colonic stenting has weaker evidence and greater technical demands; low rectal disease and multifocal peritoneal obstruction require separate consideration.
- Current antiangiogenic treatment is a concern when inserting a stent; possible antiangiogenic therapy after stenting requires an individual oncology discussion rather than a blanket rule.
02Indications, selection and cautionsWho may benefit, who needs urgent treatment and important alternatives.
The patient should have obstructive symptoms together with radiological evidence of malignant narrowing. A non-traversable tumour found during otherwise asymptomatic colonoscopy is not by itself an indication for a prophylactic stent. Treat the actual clinical problem rather than anticipating an obstruction that may never occur.
Perforation, peritonitis, systemic toxicity or convincing bowel infarction makes routine stenting inappropriate. A stent does not remove gangrenous bowel or control faecal contamination. Escalate urgently when these features emerge before or after the procedure.
Review lesion length, angulation, location, access and upstream bowel condition. Long or sharply angulated strictures and extrinsic compression can be difficult. Low rectal lesions may cause pain, tenesmus and incontinence after stenting, and should not be treated as interchangeable with sigmoid lesions.
Clarify whether the patient is receiving antiangiogenic therapy such as bevacizumab. ESGE does not suggest inserting a colonic stent during such treatment, although its recommendation is based on low-quality evidence. Later consideration of antiangiogenic therapy after a stent is a separate oncology risk-benefit decision.
Ask how avoiding a stoma, reducing immediate operative risk, obtaining relief quickly and preserving future cancer options rank for the patient. Explain that a failed stent can lead directly to emergency surgery. In advanced disease, assess whether a single intervention can realistically relieve the dominant obstruction.
03Assessment before treatmentTests and checks that guide safe selection.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Contrast-enhanced CT before stentingFirst step - Why
- Confirm malignant obstruction and decide whether the anatomy and bowel condition support stent placement.
- Interpretation and limitations
- Identify the transition, lesion length and location, local invasion, proximal dilatation, metastatic pattern and perforation. Bowel-wall gas alone has uncertain significance, but clinical or radiological evidence of infarction must not be ignored. The interpretation should support an explicit plan with a surgical alternative.
- 02
Endoscopic biopsy when safely obtainable - Why
- Establish histology during an appropriate urgent procedure without delaying decompression.
- Interpretation and limitations
- Take biopsies of the obstructing tumour when feasible. Persistent attempts at pathological confirmation should not postpone necessary relief in the emergency setting. A lesion that proves benign requires reassessment of the treatment strategy, especially when inflammatory diverticular narrowing is a possibility.
- 03
Physiological and procedural assessment - Why
- Evaluate suitability for endoscopy, sedation and a possible emergency operation.
- Interpretation and limitations
- Review observations, renal function, hydration, blood count, comorbidities, medicines and consent. A patient deteriorating while waiting for a stent may have crossed into a surgical emergency. Availability of an operator later in the day is not a reason to disregard that change.
- 04
Response assessment after deployment - Why
- Distinguish successful positioning from actual relief and identify early complications.
- Interpretation and limitations
- Confirm passage of gas or stool, improving pain and distension, and stable or improving physiology. New severe pain, guarding or systemic deterioration requires urgent surgical review and appropriate imaging if it will not delay treatment. Persistent obstruction can reflect inadequate expansion, malposition or a second level.
04Treatment approachPreparation, options, escalation and aftercare.
01Candidate selectionMake the intent and rescue route explicitFirst stepA patient has symptomatic malignant large-bowel obstruction being considered for a stent.+
- 1Review contrast CT and the patient together. Exclude perforation, peritonitis and convincing ischaemia or systemic deterioration that requires surgery; do not insert a prophylactic stent into an asymptomatic narrowing.
- 2For a suitable stable patient, agree whether the purpose is a bridge or palliation and discuss alternatives with the colorectal team. Include technical failure, perforation, emergency surgery and the possibility of a stoma before the procedure begins.
- 3Use an operator competent in colonoscopy and fluoroscopy who performs colonic stenting regularly. Avoid stricture dilatation because it increases perforation risk; select the device and deployment technique for the lesion.
- 4EscalationAfter placement, verify clinical relief and give explicit escalation instructions. Antibiotic prophylaxis is not routinely indicated solely for uncomplicated stenting, but suspected sepsis or perforation requires its own prompt treatment.
02Worked casePalliation that achieves a concrete goalA 73-year-old with unresectable metastatic colon cancer wants relief of obstruction and to return home.+
- 1CT shows a single obstructing descending-colon tumour with viable proximal bowel, no perforation and no additional obstructive level. He is not currently receiving antiangiogenic treatment; his performance status and goals are reviewed with colorectal and oncology teams.
- 2The patient chooses palliative stenting after discussion of a diverting stoma, technical failure and late re-obstruction. He accepts emergency surgery if a treatable perforation occurs, and that preference is documented alongside the overall palliative intent.
- 3An experienced operator deploys an uncovered stent without balloon dilatation. Within the following day he passes stool, pain eases and the abdomen softens; observations remain stable and gradual oral intake is tolerated.
- 4He is discharged with symptom advice and direct contact routes. At the early oncology review, he is eating and spending time at home, and the team discusses subsequent systemic therapy in the context of the stent rather than assuming every drug is now prohibited.
- 5Two months later recurrent distension prompts CT, showing tumour ingrowth and re-obstruction without perforation. After renewed review of his goals and anatomy, endoscopic stent-in-stent treatment restores stool passage and oral intake. The outcome is sustained palliation, while acknowledging that it required another procedure.
03Bridge follow-throughMove from decompression to definitive treatmentDefinitiveA stent has relieved obstruction from potentially curable left-sided colon cancer.+
- 1Confirm effective decompression, obtain histology and complete indicated staging, nutrition and medical optimisation. Arrange colorectal multidisciplinary review and a dated surgical plan rather than leaving the patient with an indefinite bridge.
- 2ESGE suggests resection at approximately two weeks after successful bridging, based on limited evidence. Individual timing depends on recovery, staging and comorbidity, and any new complication overrides the planned interval.
- 3If migration or recurrent obstruction occurs while bridging to curative surgery, consider earlier surgery rather than routine repeat stenting. Perforation requires urgent operative consideration, irrespective of the original intention to avoid an emergency operation.
04Complication rescueAct on new pain or failed decompressionThe patient worsens or remains obstructed after stent placement.+
- 1Assess circulation and the abdomen immediately and contact the surgical team. Keep the patient nil by mouth, resuscitate, and treat suspected sepsis; use urgent CT when appropriate without delaying necessary operative source control.
- 2Distinguish perforation from uncomplicated migration or tumour-related occlusion. A perforation is not managed by simply waiting for further expansion or placing another stent across the original narrowing.
- 3Choose rescue according to physiology, anatomy and agreed goals. Palliative occlusion or migration without perforation may suit endoscopic re-intervention, whereas bridging failure often leads to earlier resection.
05Complications, monitoring and follow-upAdverse effects, response and longer-term review.
- In the first hours and day after stenting, follow abdominal pain, distension, observations and bowel output. An abrupt change after initial relief is particularly concerning for a new complication.
- Confirm that oral intake is tolerated and hydration is recovering before discharge. Give clear advice to seek urgent help for severe pain, fever, vomiting, recurrent distension or loss of bowel output.
- For a bridge, verify the planned operation date and completion of the staging and optimisation steps that justify the interval. A technically successful stent without subsequent definitive planning leaves curable disease incompletely managed.
- For palliation, review the patient’s achieved benefit, nutritional intake, symptom burden and further cancer treatment. Revisit goals when re-obstruction occurs rather than automatically repeating the original intervention.
06Special situationsVariants, exceptions and circumstances that change the usual approach.
The 2020 evidence boundary
The strongest comparative evidence for bridging relates to left-sided colon cancer. Proximal colonic stenting may be considered, but the recommendation is weaker and technical demands are greater. It is misleading either to ban every proximal stent or to imply that right-sided and low rectal practice have the same evidential support as left-colon disease.
Antiangiogenic timing matters
Inserting a stent while the patient is receiving an antiangiogenic agent raises concern about perforation. ESGE separately allows consideration of antiangiogenic therapy after stenting, with weak evidence and individual assessment. Discuss timing, expected benefit and alternatives with oncology; do not invent a universal washout interval or an absolute lifelong prohibition.
Radiological success is incomplete
A device can span the stricture yet fail to produce meaningful decompression. Multifocal obstruction, incomplete expansion and extrinsic disease can all limit the benefit. The correct endpoint is improvement in symptoms and bowel function without complication, supported by further imaging when the clinical course is unclear.
The oncological discussion is balanced
Bridging stents can reduce short-term complications and stoma formation compared with emergency surgery in suitable settings, while perforation may worsen oncological outcomes. Comparative survival findings do not guarantee equivalence for every patient or every operator. Consent should acknowledge these uncertainties in terms the patient can use to make a decision.
07Common pitfallsFrequent interpretation and management errors.
- 01
Treating a colonoscopy that cannot traverse a tumour as an automatic stent indication ignores the requirement for symptomatic radiological obstruction.
- 02
Balloon-dilating a tight malignant stricture to make placement easier can increase perforation risk; it should not be a routine part of colonic stenting.
- 03
Describing all chemotherapy as contraindicated after a stent conflates conventional treatment with the more specific and timing-dependent concern about antiangiogenic therapy.
- 04
Using repeat stenting for a patient with guarding and free gas mistakes uncomplicated occlusion for perforation and delays urgent source control.