What is ESD?
Endoscopic Submucosal Dissection, or ESD, is an advanced, minimally invasive endoscopic procedure used to remove large, flat, or complex precancerous growths and early-stage cancers from the digestive tract in one piece.
Unlike EMR (Endoscopic Mucosal Resection), which may remove larger tissue in multiple pieces using a snare, ESD uses specialized endoscopic knives and instruments to carefully dissect abnormal tissue layer by layer, separating it from the deeper muscle wall. This allows larger lesions, often greater than 2 cm, to be removed en bloc when one-piece removal with EMR is difficult.
ESD is performed through an endoscope or colonoscope under deep sedation or, when appropriate, general anesthesia. Depending on the size, location, and complexity of the lesion, the procedure commonly takes 1–3 hours and may sometimes take longer.
Removing complex lesions in one piece
ESD may be considered when a lesion is large, flat, sessile, complex, or otherwise difficult to remove completely with standard snare polypectomy or EMR. En bloc removal can also provide a better specimen for detailed pathological assessment.
Large, Flat or Sessile Lesions
ESD can be used for large or complex lesions in the esophagus, stomach, or colon, including lesions greater than 2 cm that cannot be removed appropriately with standard snare polypectomy or EMR.
Early Gastrointestinal Cancer
Selected early-stage gastrointestinal cancers confined to the mucosa or suitable superficial submucosal layers may be treated endoscopically with ESD.
En Bloc Resection
Removing the lesion in one piece allows more accurate histological assessment of depth, margins, and other important pathological features.
Barrett’s Esophagus
ESD may be considered for selected extensive dysplastic or early neoplastic lesions, including certain cases associated with Barrett’s esophagus and high-grade dysplasia.
Organ Preservation
In carefully selected patients, ESD can provide an organ-preserving alternative to major surgery such as gastrectomy, esophagectomy, or colectomy.
Lower Local Recurrence Risk
When complete en bloc resection is achieved in an appropriate lesion, it can reduce the risk of incomplete removal and local recurrence compared with piecemeal resection.
What happens during the procedure?
ESD is a technically advanced procedure. The lesion is lifted away from the deeper muscle layer, precisely incised around its margins, and carefully dissected through the submucosal layer so it can be removed in one piece.
Deep Sedation or General Anesthesia
You will receive deep sedation or, when clinically appropriate, general anesthesia so that you remain comfortable and still during this longer and more intricate procedure.
Lesion Assessment
The doctor advances the endoscope or colonoscope to the lesion and carefully evaluates its location, margins, and characteristics.
Submucosal Injection
A special solution is injected beneath the lesion to lift it away from the deeper muscle layer and create a safer working cushion.
Precise Incision & Dissection
Using specialized endoscopic knives, the doctor makes controlled incisions around the lesion and carefully dissects beneath it through the submucosal layer.
En Bloc Removal
The aim is to remove the entire lesion in one piece through the mouth or anus, depending on the location of the lesion.
Pathological Examination
The specimen is retrieved intact and sent to the pathology laboratory for detailed histological assessment and staging.
ESD is generally longer and more complex than EMR
Depending on the size, location, and technical complexity of the lesion, ESD may take approximately 1–3 hours or longer. It therefore requires more time, advanced expertise, and closer monitoring than simpler endoscopic resections.
What should you expect afterward?
Observation after ESD is often more intensive than after a routine endoscopy because the treatment area is larger and the risks of bleeding and perforation are higher than with simpler procedures.
Hospital Observation
You may be observed in the hospital overnight or, depending on the procedure and your condition, for a few days.
Liquid or Soft Diet
A liquid or soft diet may initially be recommended to allow the treatment site to begin healing safely.
Mild Discomfort or Bloating
Mild abdominal discomfort, gas, or bloating may occur and usually improves with observation and supportive care.
Monitoring for Complications
Your clinical team will monitor for bleeding, perforation, fever, significant pain, infection, or other post-procedure concerns.
Pathology Results
The removed specimen is sent for pathology. Results may commonly take around 7–10 days, although timing can vary depending on the laboratory and required analysis.
Planning Further Treatment
If pathology confirms complete removal with clear margins and favorable features, some patients may not require additional major surgery or other oncological treatment.
What should you be especially careful about?
Tell your doctor about all medications, particularly anticoagulants and antiplatelet medicines. Do not stop these medicines on your own; your doctor will advise you if and when they should be withheld. Follow all fasting and preparation instructions carefully. Seek urgent medical attention if you develop severe or worsening abdominal or chest pain, fever, persistent vomiting, vomiting blood, significant rectal bleeding, black stools, dizziness, breathing difficulty, or other serious symptoms after the procedure.
Follow-up endoscopy is planned according to your individual case
Follow-up is based on the pathology findings, completeness of resection, lesion type, location, and healing. Some patients may undergo surveillance at approximately 3, 6, and 12 months and then annually, but the exact schedule should be individualized by the treating specialist.
ESD is an advanced organ-preserving endoscopic treatment
ESD is a highly specialized technique that can remove large, complex, or selected early cancerous lesions in one piece. Although it is longer and technically more demanding than EMR and carries a higher risk of complications, en bloc resection offers important advantages for accurate pathological staging and reducing local recurrence. In appropriately selected patients and experienced hands, ESD may provide curative treatment while avoiding major organ-resection surgery.