Overview
Definition:
Endoscopic Submucosal Dissection (ESD) is an advanced endoscopic technique used for the en bloc or piecemeal resection of early gastrointestinal (GI) cancers and precancerous lesions
It involves injecting a fluid into the submucosa to lift the lesion, followed by precise cutting of the mucosal and submucosal layers using specialized endoscopic knives
Surgical collaboration is crucial due to the potential for intraoperative complications and the need for definitive management of advanced lesions or those with suspected submucosal invasion.
Epidemiology:
ESD is predominantly performed for early gastric cancer (EGC), early esophageal cancer, and precancerous lesions in the esophagus, stomach, and colorectum
Incidence varies geographically, with higher rates in East Asian countries where GI cancer screening programs are well-established
The prevalence of lesions amenable to ESD is increasing globally with improved endoscopic imaging and techniques.
Clinical Significance:
ESD offers a minimally invasive alternative to traditional surgery for selected early GI malignancies, preserving organ function and reducing patient morbidity
Effective surgical collaboration ensures proper patient selection, management of complications, and definitive treatment for lesions not amenable to endoscopic resection alone, significantly impacting patient outcomes and survival rates.
Indications And Contraindications
Indications:
Well-differentiated intramucosal adenocarcinoma of the esophagus, stomach, or colorectum without submucosal invasion (T1a)
Lesions limited to the submucosa with no lymphovascular invasion or poorly differentiated histology
Selected superficial submucosal invasive cancers (T1b) with specific criteria
Barrett's esophagus with high-grade dysplasia or intramucosal adenocarcinoma.
Contraindications:
Distant metastasis or unresectable regional lymph node metastasis
Lesions with submucosal invasion beyond a certain depth (depends on location and histology)
Presence of significant comorbidities that preclude endoscopic procedures or surgery
History of extensive GI surgery that may alter anatomy or blood supply
Patients with bleeding disorders or on anticoagulation therapy that cannot be safely managed.
Diagnostic Approach And Lesion Characterization
History Taking:
Detailed history of symptoms (dyspepsia, dysphagia, abdominal pain, altered bowel habits, melena, hematochezia)
Duration and progression of symptoms
Previous GI endoscopic or surgical procedures
Comorbidities (diabetes, cardiovascular disease, respiratory illness)
Medications (anticoagulants, NSAIDs)
Family history of GI cancers.
Endoscopic Imaging And Biopsy:
High-definition white-light endoscopy with magnification
Chromoendoscopy (indigo carmine, methylene blue) to delineate lesion borders
Narrow-band imaging (NBI) for vascular pattern assessment
Endoscopic ultrasound (EUS) to assess depth of invasion and rule out lymph node involvement
Biopsies of suspicious areas to confirm histology and grade of dysplasia/neoplasia.
Imaging For Staging:
CT scan of chest, abdomen, and pelvis to rule out distant metastasis
EUS is critical for local staging of gastric and esophageal lesions
Colonoscopy with biopsies for colorectal lesions
MRI may be used in specific scenarios for local staging.
Surgical Collaboration And Preoperative Planning
Multidisciplinary Team Meeting:
Essential for optimal patient management
Involves gastroenterologists, surgeons, pathologists, radiologists, and oncologists
Discussion of lesion characteristics, staging, feasibility of ESD vs
surgery, and potential need for combined approach.
Patient Selection Criteria:
Careful review of endoscopic findings, histology, and staging
Patients must be candidates for both endoscopic resection and potentially surgery if needed
Assessment of patient's overall health and fitness for prolonged endoscopic procedures or surgical intervention.
Risk Assessment And Consent:
Thorough discussion of risks and benefits of ESD, including bleeding, perforation, stricture formation, incomplete resection, and need for surgery
Informed consent must be obtained for both ESD and potential adjunctive surgical procedures
Planning for post-ESD management, including diet, medication, and follow-up.
Endoscopic Submucosal Dissection Technique And Role Of Surgeon
Esd Procedure Overview:
Lesion marking
Submucosal injection (saline with adrenaline/methylene blue)
Circumferential mucosal incision using a specialized knife (hook knife, IT knife)
Detachment of the lesion from the submucosa
Retrieval of the specimen
Hemostasis achieved with cautery
Closure of defect (if necessary) with endoscopic clips or sutures.
Surgical Intervention During Esd:
Preparedness for intraoperative bleeding requiring immediate surgical consultation or conversion to laparotomy/laparoscopy
Management of esophageal or gastric perforation, which may necessitate urgent surgical repair
Handling of large or deeply invasive lesions where complete endoscopic resection is not feasible.
Timing Of Surgical Intervention:
Urgent conversion to surgery for uncontrollable bleeding or perforation
Delayed surgery for patients with positive margins after ESD, suspected residual disease on follow-up imaging, or regional lymph node metastasis identified post-ESD
Palliative surgery for unresectable disease after failed or incomplete ESD.
Postoperative Care And Surveillance
Immediate Post Esd Care:
Nil per os (NPO) initially
Intravenous fluids
Pain management
Close monitoring for vital signs, signs of bleeding (hematemesis, melena, hemodynamic instability), and perforation (abdominal pain, rigidity, fever)
Prophylactic antibiotics may be considered.
Dietary Advancement:
Gradual reintroduction of oral intake starting with clear liquids, progressing to soft diet as tolerated
Avoiding irritating foods
Speech therapy referral if esophageal ESD is performed, to monitor for aspiration risk.
Surveillance Strategy:
Regular endoscopic surveillance to check for local recurrence or metachronous lesions
Surveillance intervals depend on lesion characteristics and risk factors
Imaging studies as per protocol for staging and metastasis screening
Long-term follow-up to monitor for complications like strictures and assess overall survival.
Complications And Management
Early Complications:
Bleeding (most common, can be immediate or delayed)
Perforation (risk higher with thicker submucosa or difficult dissection)
Esophageal stenosis (risk higher with extensive resection in the esophagus)
Nerve injury.
Late Complications:
Stricture formation (especially in esophagus and colorectum)
Recurrence of lesion
Gastric outlet obstruction
Fistula formation (rare).
Management Of Complications:
Bleeding: Endoscopic hemostasis (clipping, cautery), blood transfusion, rarely surgical intervention
Perforation: Nasogastric decompression, bowel rest, antibiotics, endoscopic clipping, or immediate surgical repair
Strictures: Endoscopic balloon dilation, steroid injections, or surgical revision
Recurrence: Repeat endoscopy with biopsy, further resection (endoscopic or surgical), or adjuvant therapy.
Key Points
Exam Focus:
Understanding the indications and contraindications for ESD
Recognition of lesions suitable for ESD versus upfront surgery
Management of intraoperative and postoperative complications
The critical role of the multidisciplinary team
Histopathological assessment post-ESD for margin status and submucosal invasion.
Clinical Pearls:
Thorough preoperative staging is paramount
Always consider the need for potential surgical conversion during ESD
Effective submucosal injection is key to a safe and complete dissection
Meticulous hemostasis is crucial to prevent delayed bleeding
Close surveillance is essential to detect recurrence early.
Common Mistakes:
Inadequate patient selection for ESD
Failure to adequately assess submucosal invasion
Underestimating the risk of perforation or bleeding
Incomplete resection with positive margins
Insufficient postoperative surveillance leading to delayed detection of recurrence.