Version July 2025
INTRODUCTION —
Endoscopic resection is an alternative to surgical resection for removing mucosal or submucosal gastrointestinal lesions and for removing intramucosal cancers. Methods for endoscopic resection using advanced techniques include:
●Endoscopic mucosal resection (EMR) – EMR typically involves snare resection of a nonpedunculated or flat lesion.
●Endoscopic submucosal dissection (ESD) – ESD uses specialized endoscopic tools to dissect lesions from the submucosa.
Endoscopic resection offers both diagnostic and therapeutic capability. Curative resection is often achieved for lesions that are limited to the mucosa and the superficial layers of the submucosa.
This topic will discuss the general endoscopic evaluation of gastrointestinal lesions prior to resection, methods for resection, and adverse events. Management and prognosis of patients with specific gastrointestinal lesions requiring endoscopic resection are discussed separately:
●Barrett's esophagus with high-grade dysplasia – (See "Barrett's esophagus: Treatment of high-grade dysplasia or early cancer with endoscopic resection".)
●Superficial esophageal cancer – (See "Management of superficial esophageal cancer".)
●Early gastric cancer – (See "Early gastric cancer: Management and prognosis".)
●Colon polyps – (See "Endoscopic removal of large colon polyps".)
CLINICAL APPLICATIONS —
We perform endoscopic resection for lesions located throughout the gastrointestinal tract (ie, from the esophagus to the rectum) that have very low risk of lymph node metastasis, although specific indications and removal techniques for each site may vary [1,2]. As examples, we may use endoscopic resection for treating superficial esophageal cancer, early gastric cancer, or large colon polyps. (See "Management of superficial esophageal cancer" and "Early gastric cancer: Management and prognosis" and "Endoscopic removal of large colon polyps".)
Esophageal lesions and superficial cancers — Endoscopic resection is an option for patients with superficial esophageal cancers that are small (eg, <2 cm diameter), involve less than one-third of the esophageal wall circumference, and are limited to the mucosa (corresponding to a T stage of T1a) (table 1) [3]. (See "Management of superficial esophageal cancer", section on 'Endoscopic therapy'.)
Endoscopic resection is also an option for patients with high-grade dysplasia in Barrett's esophagus. (See "Barrett's esophagus: Treatment of high-grade dysplasia or early cancer with endoscopic resection".)
For patients with superficial esophageal cancer or high-grade dysplasia, endoscopic resection may be combined with ablation therapy using radiofrequency ablation (RFA) or argon plasma coagulation (APC) [4,5]. RFA for patients with Barrett's esophagus and dysplasia or intramucosal cancer is discussed in more detail separately. (See "Barrett's esophagus: Treatment with radiofrequency ablation".)
Early gastric cancer and other gastric lesions — We use endoscopic resection for removing early gastric cancers that are confined to the mucosa and those extending to the superficial submucosa. Specific criteria for selecting patients with early gastric cancer for endoscopic resection are discussed separately. (See "Early gastric cancer: Management and prognosis".)
We also use endoscopic resection for removing some gastric subepithelial tumors, such as gastrointestinal stromal tumors, leiomyomas, and neuroendocrine tumors. Factors informing the decision to perform endoscopic resection include the lesion's layer of origin, lesion size, histology (risk of metastatic disease), availability of endoscopic expertise, and the patient's surgical risk. Subepithelial lesions confined to the muscularis mucosa and submucosa may be resected en bloc by endoscopic mucosal resection (EMR) if they are ≤1 cm in size, and by endoscopic submucosal dissection (ESD) if they are >1 cm. However, lesions originating from the deeper layers, such as muscularis propria, may require full thickness endoscopic resection or submucosal tunneling endoscopic resection (STER) to achieve R0 (ie, complete) resection [6-8]. (See "Local treatment for gastrointestinal stromal tumors, leiomyomas, and leiomyosarcomas of the gastrointestinal tract".)
Colorectal lesions — We perform endoscopic resection with advanced techniques for removing large colon polyps (ie, >2 cm) and small rectal neuroendocrine tumors. (See "Staging, treatment, and surveillance of localized well-differentiated gastrointestinal neuroendocrine tumors", section on 'Rectum'.)
Nonpedunculated colorectal lesions that are confined to the mucosa may be removed using EMR. However, we do not use EMR for lesions with characteristics of submucosal invasion (eg, depressed lesion, failure to lift after submucosal injection).
In addition to EMR, ESD is being used in the treatment of colon polyps and some colorectal cancers [9]. It is important to obtain en-bloc resection of lesions with suspected or confirmed cancer to achieve negative margins. We use ESD to remove cancerous colon lesions >2 cm. EMR is an acceptable approach for smaller cancerous lesions. However, use of ESD may be limited by available expertise and lesion location. In these cases, surgical approach is favored. (See "Endoscopic removal of large colon polyps", section on 'Endoscopic submucosal dissection techniques'.)
PATIENT PREPARATION —
The preprocedure preparation for patients undergoing endoscopic resection is similar to that described for patients undergoing gastrointestinal endoscopy, and these issues are discussed separately:
●Patients with lesions in the upper gastrointestinal tract – (See "Overview of upper gastrointestinal endoscopy (esophagogastroduodenoscopy)", section on 'Preprocedure considerations'.)
●Patients with lesions in the lower gastrointestinal tract (ie, colorectum) – (See "Overview of colonoscopy in adults", section on 'Patient preparation'.)
Management of antithrombotic agents for patients undergoing endoscopy is discussed separately:
●(See "Management of anticoagulants in patients undergoing endoscopic procedures".)
●(See "Management of antiplatelet agents in patients undergoing endoscopic procedures".)
Antibiotic prophylaxis is not routinely indicated for endoscopic resection.
PREPROCEDURE EVALUATION
Preprocedure testing — For patients undergoing endoscopic resection, the preprocedure evaluation is similar to the evaluation for all patients prior to endoscopic procedures (eg, assess cardiopulmonary risk). These issues are discussed in detail separately. (See "Anesthesia for gastrointestinal endoscopy in adults", section on 'Preprocedure evaluation'.)
Inspecting the lesion
Direct endoscopic visualization — After a gastrointestinal lesion is identified endoscopically, we inspect the lesion for signs of malignancy or submucosal invasion and we delineate the lesion's margins. Lesion characteristics that inform the risk of invasive malignancy and the likelihood of achieving R0 (ie, complete) resection include size, morphology, surface pattern, and anatomic location. We categorize lesions based on morphology (eg, protruding polypoid lesions [sessile or pedunculated], nonpolypoid lesions, excavated/ulcerated lesions). Several classification systems stratify lesions by the magnitude of risk for submucosal invasive cancer. As an example, the Paris classification categorizes superficial colon polyps (type 0) as polypoid, nonpolypoid or excavated (table 2 and figure 1) [10]:
●Type 0-I lesions are polypoid and are subcategorized as:
•Type 0-Ip – protruded, pedunculated
•Type 0-Is – protruded, sessile
●Type 0-II lesions are nonpolypoid and are subcategorized as:
•Type 0-IIa – slightly elevated
•Type 0-IIb – flat
•Type 0-IIc – slightly depressed
●Type 0-III lesions are excavated
Depressed lesions may have invasion into the submucosa, even when they are small, and deep invasion is a contraindication to EMR. The Paris classification notes that deep invasion is more likely when [10]:
●The diameter of the depressed area is >15 mm
●The border of an elevated or depressed lesion (Paris type 0-IIa or 0-IIc, respectively) presents as a smooth circle without indentations
●The lesion does not lift after submucosal fluid injection (see 'Creating a submucosal fluid cushion' below)
We do not use endoscopic resection for lesions with any of the above criteria for deep invasion, especially the failure to lift.
Another classification system developed by the Japanese Society for Gastroenterological Endoscopy (JSGE) to evaluate early gastric cancer may also be applied to superficial cancers at other sites in the gastrointestinal tract [11]. The system recognizes four types of early endoluminal cancers (figure 2):
●Type I lesions are polypoid or protuberant and are subcategorized as:
•Ip – pedunculated
•Ips/sp – subpedunculated
•Is – sessile
●Type II lesions are flat and are further subcategorized as:
•IIa – superficial elevated
•IIb – flat
•IIc – flat depressed
•IIc+IIa lesions – elevated area within a depressed lesion
•IIa+IIc lesions – depressed area within an elevated lesion
●Type III lesions are ulcerated
●Type IV lesions are lateral spreading
Lesions that harbor ulceration or an area of depression are more likely to have submucosal invasive cancer [12].
Other methods — In addition to direct endoscopic visualization, examination with endoscopic ultrasound (EUS) may help determine the tumor depth and inform selecting lesions that are suitable for en bloc resection. As an example, we may use EUS to evaluate patients with suspected superficial esophageal cancer. However, histologic examination of the specimen following endoscopic resection may be more accurate than EUS for determining depth of tumor invasion [13]. The role of EUS for evaluating patients with esophageal cancer is discussed in more detail elsewhere. (See "Endoscopic ultrasound for evaluating patients with esophageal cancer" and "Management of superficial esophageal cancer".)
PROCEDURES
Goals — The goals of endoscopic resection are to:
●Completely remove the lesion (referred to as R0), while preserving the gastrointestinal organ of origin
●Minimize need for subsequent resections
●Minimize the risk of adverse events (eg, bleeding) and lesion recurrence
Endoscopic mucosal resection — Endoscopic mucosal resection (EMR) is a technique using snare excision for removing large flat or nonpedunculated lesions that are confined to the mucosa or superficial submucosa of the gastrointestinal tract [14].
Equipment — Equipment needs vary depending on resection technique and endoscopist preference. In general, we confirm that the following endoscopic accessories are available prior to performing EMR [15]:
●Transparent cap for the tip of the endoscope
●Catheter with injection needle (23 or 25 gauge)
●Multiband ligation device
●Snare that is used with an electrosurgical device (also referred to as a hot snare)
●Coagulation devices to control bleeding (eg, coagraspers, endoscopic clips) (see "Endoscopic clip therapy in the gastrointestinal tract: Bleeding lesions and beyond", section on 'Available clips')
Resection techniques — Methods for performing EMR include:
●Lift-and-cut technique – The lift-and-cut technique involves injecting fluid into the submucosal space to lift the lesion from the muscularis propria (figure 3). Next, the lesion is removed by snare excision. The snare may be used with electrocautery (referred to as hot snare EMR technique) or without electrocautery (referred to as cold snare EMR technique). We often use the lift-and-cut technique for removing large nonpedunculated colon polyps.
●Suction-and-cut technique – The suction-and-cut technique involves submucosal fluid injection followed by suctioning and then banding the lesion using an endoscopic ligation device (also referred to as the band-and-snare technique). Banding the lesion creates a pseudo-polyp that is subsequently removed by snare excision (figure 4 and picture 1) [16,17]. Commercial kits designed for the band-and-snare technique are available.
An alternative to band ligating the lesion involves performing submucosal injection followed by suctioning the lesion into a transparent cap affixed to the tip of the endoscope (referred to as cap-assisted EMR) [18]. First, we inject a moderate volume of saline (20 to 40 mL) to raise the lesion. While using controlled suction, we place the snare through the transparent cap and around the lesion at the middle of the submucosal fluid cushion (rather than at the base) [19,20]. Next, we close the snare to remove the lesion (figure 5).
Creating a submucosal fluid cushion — The goal of submucosal injection is to create a submucosal fluid cushion that lifts the lesion away from the muscularis propria and possibly lowers the risk of perforation.
The technique for submucosal injection prior to endoscopic resection is summarized as follows:
●Pass a catheter with a retractable injection needle through the endoscope's accessory channel.
●Insert the needle into the mucosa so that the beveled needle tip is entirely beneath the mucosa to facilitate injecting fluid into the submucosa.
●Inject at one or multiple sites along the perimeter of the lesion [21].
We use a dynamic injection technique that involves redirecting the needle position while it remains beneath the intestinal mucosa [22]. Typically, the total volume of fluid injected is at least 10 to 40 mL [23,24].
A puckering or non-lifting appearance after submucosal injection of a lesion suggests invasion into the muscularis propria [25].
Selecting a solution for submucosal injection is informed by product availability, desired duration of effect, endoscopist preference, and cost. We typically use hydroxyethyl starch (hetastarch) mixed with methylene blue and diluted epinephrine (1:200,000) for submucosal injection prior to endoscopic resection [26,27]. We use methylene blue (a staining dye) to delineate the submucosa from the deeper muscle layer and to highlight the lesion's margins. We include diluted epinephrine to lower the risk of immediate post-resection bleeding [21].
Several proprietary submucosal injectate solutions have become commercially available. Other injectate solutions for endoscopic resection that have been studied include hypertonic saline, 50 percent dextrose, 10 percent glycerol, 5 percent fructose, a fibrinogen mixture, sodium hyaluronate, and hydroxypropyl methylcellulose (HPMC) [27-33].
Based on clinical experience and limited data, these injectate solutions are more effective than isotonic saline because saline is absorbed quickly (eg, within approximately three minutes), resulting in a transient lesion lift [25,26].
Adverse events — Endoscopic resection using EMR is generally a safe procedure, although major adverse events include bleeding and perforation [34,35].
●Bleeding – The reported rate of postprocedure bleeding associated with EMR varies widely and by anatomic location (1 to 2 percent in the esophagus, 5 percent in the stomach, 5 to 10 percent in the duodenum, and 2 to 24 percent in the colorectum) [36-40]. Most patients with postprocedure bleeding present within a few days after the procedure [41].
For patients with intraprocedural bleeding (also referred to as immediate bleeding), we typically treat the source using endoscopic methods such as injection of diluted epinephrine solution, endoscopic clipping, and/or thermal coagulation.
For patients with significant postprocedure bleeding (ie, hemodynamic instability, drop in hemoglobin >2 g/dL), we typically perform repeat endoscopy or colonoscopy, depending on the site of EMR. We use thermal methods, endoscopic clips, or less commonly, endoscopic suturing to achieve long-term hemostasis by treating the culprit vessel. These endoscopic techniques achieve hemostasis in most cases of bleeding related to EMR, and surgery is rarely necessary. (See "Management and prevention of bleeding after colonoscopy with polypectomy".)
●Perforation – Post-EMR perforation is uncommon (ie, less than 1 percent) [36,42]. Perforation may be immediate and detected endoscopically at the time of the procedure, whereas delayed perforation is diagnosed after EMR by clinical symptoms (eg, abdominal pain, fever) and imaging [43]. We typically manage perforation related to endoscopic resection with endoscopic clipping or suturing [43].
●Other events – Other adverse events related to EMR include:
•Transient bacteremia – Transient bacteremia that is not associated with sepsis may be common following endoscopic resection. In a study of 38 patients who underwent cap-assisted EMR for upper gastrointestinal lesions, transient bacteremia rates of 5 percent have been reported, but the risk of subsequent sepsis is uncertain [44].
•Stricturing – Endoscopic resection of esophageal lesions that involve more than 50 percent of the luminal circumference has been associated with increased risk of stricture formation [36,45]. Patients with esophageal stricture typically report dysphagia to solids. (See "Approach to the evaluation of dysphagia in adults", section on 'Esophageal stricture'.)
We treat most benign esophageal strictures with endoscopic dilation, and this is discussed separately. (See "Endoscopic interventions for nonmalignant esophageal strictures in adults".)
•Postpolypectomy coagulation syndrome – Postpolypectomy coagulation syndrome (PCS) refers to the development of abdominal pain, fever, leukocytosis, and peritoneal inflammation in the absence of bowel perforation after polypectomy or EMR with electrocoagulation, and PCS is discussed separately. (See "Postpolypectomy coagulation syndrome".)
Endoscopic submucosal dissection (ESD) — Endoscopic submucosal dissection (ESD) is a specialized technique that uses a modified needle-knife (ESD-knife) to remove a gastrointestinal lesion by dissecting through the submucosa [46-50]. ESD accomplishes en bloc removal of larger (>2 cm) lesions. ESD was developed for treating early gastric cancer [46,47,51,52], but its use has expanded to include esophageal and esophagogastric junction lesions [49,53-59], duodenal lesions [60-62], and colon lesions [48,63-65]. (See "Early gastric cancer: Management and prognosis".)
Equipment — We use the following endoscopic accessories during ESD [66]:
●Transparent cap attached to the tip of the endoscope – The cap may facilitate better endoscopic control during the dissection step.
●Catheter with injection needle (23 or 25 gauge).
●ESD-knife – ESD knives are available in a variety of configurations and features (eg, needle-type knives, insulated tip knives, scissor-type knives). Selecting a specific knife is largely dependent on endoscopist experience and preference (picture 2).
●Coagulation device to control bleeding (eg, hot biopsy forceps, coagraspers).
Technique — The technical procedure of ESD includes inspecting the lesion and defining its margins, marking mucosal borders, injecting fluid into the submucosal plane, incising the lesion's circumference, and then submucosal dissection [66]. The technique requires specialized endoscopic skills and focused training to acquire these skills.
The steps of ESD are summarized as follows:
●Examine the lesion's margins with both high-definition white light and specialized imaging (eg, narrow band imaging [NBI] or chromoendoscopy). (See "Chromoendoscopy".)
●Mark the circumference of the lesion at 3 to 5 mm from the margin with electrocautery or argon plasma coagulation.
●Perform submucosal injection under the markings. (See 'Creating a submucosal fluid cushion' above.)
●Guided by the markings, incise the lesion in a circumferential fashion with the ESD-knife while applying electrocautery. The incision creates a mucosal flap and access for submucosal dissection.
●Inject additional submucosal solution under the incised mucosal flap.
●Use the ESD knife to perform electrocautery dissection strand-by-strand until the entire lesion is released from its submucosal attachment. A method of counter-traction (eg, suture-pulley) is often used to improve visualization.
The submucosal dissection step tends to be the most technically challenging. Submucosal dissection often requires treating exposed submucosal vessels and continuously maintaining the endoscope within the submucosal plane, in addition to avoiding incising either side of the dissection plane (ie, the dysplastic tissue [superficial side] and the muscularis propria [deep side]).
Various electrocautery settings may be used for both incision and dissection steps of the procedure, and settings are informed by endoscopist preference and the specific electrosurgical unit. (See "Endoscopic biliary sphincterotomy", section on 'Electrosurgical devices'.)
Hybrid ESD is a modification of standard ESD technique that involves marking the lesion and incising it using the above mentioned technique but with only partial submucosal dissection. This step is followed by EMR of the lesion using a snare. (See 'Endoscopic mucosal resection' above.)
Hybrid ESD minimizes the amount of submucosal dissection, which tends to be the most challenging and time-consuming part of the procedure [67].
Adverse events — While ESD is generally safe when performed by specialized endoscopists, procedure-related adverse events include bleeding, perforation, and stricturing [63,66,68-72]:
●Bleeding – The reported rate of postprocedure bleeding associated with ESD varies by anatomic location (1 to 2 percent in the esophagus, 5 to 10 percent in the stomach, 5 to 17 percent in the duodenum, and 3 percent in the colorectum) [72,73]. Reported risk factors for bleeding include lesion size >40 mm and antithrombotic drug therapy [73].
For patients with intraprocedural bleeding, we treat the bleeding immediately with methods such as thermal coagulation or hemostatic forceps. For most patients with significant postprocedure bleeding (ie, hemodynamic instability, drop in hemoglobin >2 g/dL), we typically perform endoscopy or colonoscopy depending on the site of endoscopic resection. We use thermal methods or endoscopic clips to achieve long-term hemostasis by treating the culprit vessel. (See "Management and prevention of bleeding after colonoscopy with polypectomy".)
●Perforation – Perforation may be immediate and detected endoscopically at the time of the procedure, whereas delayed perforation is diagnosed after ESD by clinical symptoms (eg, abdominal pain, fever) and imaging. The estimated perforation rate related to ESD varies by anatomic location (1.5 to 5 percent in the esophagus, less than 3 percent in the stomach, 10 percent in the duodenum, and 4 to 9 percent in the colorectum) [74-79]. Factors that have been associated with an increased risk of perforation from ESD include lesion size >2 cm and upper stomach location with gastric ESD [80].
•Immediate perforation – For patients with immediate perforation, we typically close the defect with endoscopic clips (eg, through-the-scope or over-the-scope clips) during the procedure. Perforations associated with ESD of colorectal lesions can often be managed by endoscopic clipping and medical management (eg, hospitalization, bowel rest, intravenous fluids) [65,81-83]. However, surgery may be required in some cases. As an example, in an observational study including 310 colorectal lesions removed with ESD, intraprocedural perforation occurred with 14 lesions (5 percent), and all were successfully treated with endoscopic clipping [81].
•Delayed perforation – We obtain surgical consultation for patients with delayed perforation and manage such patients in a multidisciplinary fashion. Some patients with delayed perforation may be managed with endoscopic intervention (eg, stent placement for treating esophageal perforation), whereas others may require surgical intervention to close the defect [84,85].
●Strictures – Following ESD, patients who have a mucosal defect involving >50 percent of the luminal circumference are at risk for postprocedure stricture formation [86,87]. In addition, most patients who undergo circumferential esophageal resection >5 cm in length develop stricturing. (See "Barrett's esophagus: Treatment of high-grade dysplasia or early cancer with endoscopic resection", section on 'Complications'.)
We manage most ESD-related esophageal strictures with endoscopic balloon dilation. In a study including 83 patients who developed esophageal stricture following ESD for either Barrett's neoplasia or squamous cell carcinoma, endoscopic dilation was clinically successful in most patients (84 percent) after a median of three endoscopic sessions [87].
For patients with refractory strictures despite endoscopic dilation, we typically perform glucocorticoid injection (eg, triamcinolone acetonide) into the stricture and balloon dilation during one endoscopic session. These interventions are discussed in more detail separately. (See "Endoscopic interventions for nonmalignant esophageal strictures in adults", section on 'Refractory strictures'.)
●Other adverse events – Post ESD electrocoagulation syndrome (PEECS) is very rare following ESD of upper gastrointestinal lesions but occurs more often in the colon (5 to 14 percent) [88-90]. PEECS develops when electrical current applied during the procedure extends past the mucosa and into the muscularis propria and serosa, resulting in a transmural burn without perforation. Risk factors for PEECS include cecal location, female sex, and submucosal fibrosis [88].
PEECS is suspected in patients who develop fever, abdominal tenderness, and/or leukocytosis following ESD of a colonic or rectal lesion. Evaluation includes abdominal computed tomography scan (with water-soluble oral contrast and intravenous contrast) to exclude frank perforation. The management of PEECS is similar to management of postpolypectomy coagulation syndrome (ie, inpatient observation, bowel rest, empiric antibiotic therapy), and these issues are presented separately. (See "Postpolypectomy coagulation syndrome".)
Documentation — We include the following information in the endoscopy report to document endoscopic resection (see 'Preprocedure evaluation' above):
●Location of resected lesion (eg, gastric antrum, ascending colon)
●Lesion characteristics suggesting resection feasibility (eg, size, morphology)
●Method of endoscopic resection including use of submucosal fluid injection
●Whether lesion was resected en bloc or in piecemeal fashion
Postprocedure care — After the procedure, patients are recovered from sedation or anesthesia. Symptoms or signs such as fever, new/worsening abdominal pain, or rectal bleeding after the endoscopic procedure are not typical and warrant further investigation. (See 'Adverse events' above.)
Following the procedure, most endoscopists instruct patients to resume a normal diet.
POST-RESECTION SURVEILLANCE —
We perform endoscopic surveillance following endoscopic resection to detect disease recurrence and metachronous lesions. The timing and frequency of endoscopic surveillance is individualized and informed by lesion location, lesion size, lesion histology, number of lesions, resection method (eg, piecemeal or en bloc resection), patient characteristics (eg, age, comorbidities), and society guidance [1,91-94]. As an example, patients who undergo piecemeal EMR for a large nonpedunculated colon polyp require surveillance examination sooner than patients who had en bloc resection because of the increased risk of residual disease with piecemeal resection [95]. (See "Endoscopic removal of large colon polyps".)
Endoscopic surveillance is discussed in more detail separately:
●Barrett's esophagus with high-grade dysplasia or intramucosal cancer – (See "Barrett's esophagus: Treatment with radiofrequency ablation", section on 'Follow-up endoscopy' and "Barrett's esophagus: Treatment of high-grade dysplasia or early cancer with endoscopic resection".)
●Early gastric cancer – (See "Early gastric cancer: Management and prognosis", section on 'Management after endoscopic resection'.)
●Colon polyps – (See "Overview of colon polyps", section on 'Surveillance'.)
SOCIETY GUIDELINE LINKS —
Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Gastric cancer" and "Society guideline links: Esophageal cancer" and "Society guideline links: Colon polyps".)
SUMMARY AND RECOMMENDATIONS
●Background – Endoscopic resection is a method for removing mucosal or submucosal gastrointestinal lesions and for removing intramucosal cancers. Specific techniques include:
•Endoscopic mucosal resection (EMR) – EMR involves snare excision of a nonpedunculated or flat lesion (figure 4 and picture 1). (See 'Endoscopic mucosal resection' above.)
•Endoscopic submucosal dissection (ESD) – ESD uses specialized endoscopic tools to dissect lesions from the submucosa (picture 2). (See 'Endoscopic submucosal dissection (ESD)' above.)
●Goals – The goals of endoscopic resection are to (see 'Goals' above):
•Completely remove the lesion (referred to as R0), while preserving the gastrointestinal organ of origin
•Minimize need for subsequent resections
•Minimize the risk of adverse events (eg, bleeding) and lesion recurrence
●Preprocedure evaluation – Prior to endoscopic resection, we inspect the gastrointestinal lesion for signs of invasive malignancy or submucosal invasion, and we delineate the lesion's margins. Lesion characteristics that inform the risk of invasive malignancy and the likelihood of achieving R0 (ie, complete) resection include size, morphology, surface pattern, and anatomic location. We categorize lesions based on morphology (eg, polypoid [sessile or pedunculated], nonpolypoid, excavated/ulcerated) (table 2 and figure 1). (See 'Preprocedure evaluation' above.)
●Clinical applications – We perform endoscopic resection for lesions located throughout the gastrointestinal tract (ie, from the esophagus to the rectum) that are limited to the mucosa or submucosa and have very low risk of lymph node metastasis. In general, indications for endoscopic resection include:
•Barrett's esophagus with high-grade dysplasia – (See "Barrett's esophagus: Treatment of high-grade dysplasia or early cancer with endoscopic resection".)
•Superficial esophageal cancer – (See "Management of superficial esophageal cancer", section on 'Endoscopic therapy'.)
•Early gastric cancer – (See "Early gastric cancer: Management and prognosis".)
•Large colon polyps – (See "Endoscopic removal of large colon polyps".)
●Adverse events – While EMR and ESD are generally safe procedures, serious adverse events related to the procedure include bleeding and perforation. For most patients with bleeding related to endoscopic resection, endoscopic therapy using injection therapy, thermal coagulation, and/or endoscopic clipping usually achieves long-term hemostasis, and surgery is rarely necessary. (See 'Procedures' above.)
●Post-resection surveillance – We perform endoscopic surveillance following endoscopic resection to detect disease recurrence and metachronous lesions. The timing and frequency of endoscopic surveillance is individualized and informed by lesion location, lesion size, lesion histology, number of lesions, resection method (eg, piecemeal or en bloc resection), patient characteristics (eg, age, comorbidities), and society guidance. (See 'Post-resection surveillance' above.)
ACKNOWLEDGMENT —
The UpToDate editorial staff thank Dr. Mustafa Kathawala, MD, and Dr. Christopher Gostout, MD, for their contributions as author to prior versions of this topic review.
