Endoscopic Submucosal Dissection: Indications and Application in Western Endoscopy Practice

Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection

Therapeutic endoscopy is an emerging field within general surgery. This article explores the evidence for and usage of endoscopic mucosal resection and endoscopic submucosal dissection throughout the gastrointestinal tract. We aim to educate surgeons and provide an understanding of these techniques. With education and appropriate training, the surgeon will gain confidence and hopefully adopt these tools into their daily practice.

A deep learning method for delineating early gastric cancer resection margin under chromoendoscopy and white light endoscopy

BACKGROUND

Accurate delineation of cancer margins is critical for endoscopic curative resection. This study aimed to train and validate real-time fully convolutional networks for delineating the resection margin of early gastric cancer (EGC) under indigo carmine chromoendoscopy (CE) or white light endoscopy (WLE), and evaluated its performance and that of magnifying endoscopy with narrow-band imaging (ME-NBI).

METHODS

We collected CE and WLE images of EGC lesions to train fully convolutional networks ENDOANGEL. ENDOANGEL was tested both on stationary images and endoscopic submucosal dissection (ESD) videos. The accuracy and reliability of ENDOANGEL and NBI-dependent delineation were further evaluated by a novel endoscopy-pathology point-to-point marking.

RESULTS

ENDOANGEL had an accuracy of 85.7% in the CE images and 88.9% in the WLE images under an overlap ratio threshold of 0.60 in comparison with the manual markers labeled by the experts. In the ESD videos, the resection margins predicted by ENDOANGEL covered all areas of high-grade intraepithelial neoplasia and cancers. The minimum distance between the margins predicted by ENDOANGEL and the histological cancer boundary was 3.44 ± 1.45 mm which outperformed the resection margin based on ME-NBI.

CONCLUSIONS

ENDOANGEL has the potential to assist endoscopists in delineating the resection extent of EGC under CE or WLE during ESD.

Pathologic assessment of endoscopic resection specimens with superficial carcinoma of the esophagus: current practice and practical issues

Endoscopic resection (ER) has become the first-line therapy for early esophageal cancer and offers a treatment alternative to surgery, owing to less morbidity and better quality of life. ER techniques include endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). EMR is faster, simpler, and cheaper than ESD, but limited by its ability to resect lesions larger than 1.5 centimeters. Piecemeal EMR has limitations, including a high local recurrence rate and a suboptimal specimen for an accurate pathologic assessment. ESD, on the other hand, allows en bloc resections with negative (R0) margins, irrespective of lesion size, providing an excellent pathologic specimen, however, is technically challenging with a higher risk of complications. The evaluation of ER specimens in pathology varies slightly from institution to institution. Our review summarizes the current practices and issues in the pathologic assessment of esophageal ER specimens, which highlights the necessity of a systematic approach and standardization of both macroscopic and microscopic evaluation. There is a need for a comprehensive and standardized pathology report that will allow for uniform terminology for endoscopists, surgeons, and pathologists, which, in turn, will result in better treatment guidance.

Pathological assessment of endoscopic resections of the gastrointestinal tract: a comprehensive clinicopathologic review

Endoscopic resection (ER) allows optimal staging with potential cure of early-stage luminal malignancies while maintaining organ preservation. ER and surgery are non-competing but complementary therapeutic options. In addition, histological examination of ER specimens can either confirm or refine the pre-procedure diagnosis. ER is used for the treatment of Barrett's related early carcinomas and dysplasias, early-esophageal squamous cell carcinomas and dysplasias, early gastric carcinomas and dysplasia, as well as low-risk submucosal invasive carcinomas (LR-SMIC) and, large laterally spreading adenomas of the colon. For invasive lesions, histological risk factors predict risk of lymph node metastasis and residual disease at the ER site. Important pathological risk factors predictive of lymph node metastasis are depth of tumor invasion, poor differentiation, and lymphovascular invasion. Complete resection with negative margins is critical to avoid local recurrences. For non-invasive lesions, complete resection is curative. Therefore, a systematic approach for handling and assessing ER specimens is recommended to evaluate all above key prognostic features appropriately. Correct handling starts with pinning the specimen before fixation, meticulous macroscopic assessment with orientation of appropriate margins, systematic sectioning, and microscopic assessment of the entire specimen. Microscopic examination should be thorough for accurate assessment of all pathological risk factors and margin assessment. Site-specific issues such as duplication of muscularis mucosa of the esophagus, challenges of assessing ampullectomy specimens and site-specific differences of staging of early carcinomas throughout the gastrointestinal tract (GI) tract should be given special consideration. Finally, a standard, comprehensive pathology report that allows optimal staging with potential cure of early-stage malignancies or better stratification and guidance for additional treatment should be provided.

Cost of Endoscopic Submucosal Dissection Versus Endoscopic Piecemeal Mucosal Resection in the Colorectum

BACKGROUND

Few studies have compared the costs of colorectal endoscopic submucosal dissection (ESD) and endoscopic piecemeal mucosal resection (EPMR).

AIMS

Here, we aimed to investigate the cost-effectiveness of these approaches by analyzing clinical outcomes and costs.

METHODS

Data from patients undergoing colorectal ESD and EPMR were retrospectively reviewed. Clinical outcomes (procedure time, complete resection, and recurrence) were compared, and total direct costs (procedural and follow-up) were assessed.

RESULTS

Data from 429 ESD and 115 EPMR patients were included in the analysis. The complete resection rate was significantly higher (83.9% vs. 32.2%, p < 0.001), recurrence rate was lower (0.5% vs. 7.1%, p < 0.001), procedure time was longer (55.4 ± 47.0 vs. 25.6 ± 32.7 min, p < 0.001), and total direct procedural costs at the initial resection were higher (1480.0 ± 728.0 vs. 729.8 ± 299.7 USD, p < 0.001) in the ESD group than in the EPMR group. The total number of surveillance endoscopies was higher in the EPMR group (1.7 ± 1.5 vs. 1.3 ± 1.1, p = 0.003). The cumulative total costs of ESD and EPMR were comparable at 3 and 2 years' follow-up in the adenoma and mucosal/superficial submucosal cancer subgroups, respectively.

CONCLUSIONS

Colorectal ESD was associated with higher complete resection and lower recurrence rates. EPMR showed shorter procedure times and similar cumulative total direct costs. ESD or EPMR should be chosen based on both clinical outcomes and cost-effectiveness.

Intra-abdominal pressure during endoscopic full-thickness resection comparing manual and automatic control insufflation: a block-randomized porcine study

BACKGROUND AND STUDY AIMS

An automatic carbon dioxide (CO2) insufflating system (SPACE) was developed to stabilize intra-lumenal pressure (ILP) during endoscopic interventions. This study investigated whether SPACE could improve the control and monitoring of extra-lumenal intra-abdominal pressure (IAP) after establishing a perforation during endoscopic full-thickness resection (EFTR) of the gastric wall in porcine models.

MATERIALS AND METHODS

After first establishing the optimal preset pressure for gastric EFTR in four pigs, we compared IAP dynamics during EFTR between manual insufflation and SPACE using a block-randomized study (n = 10). IAP was percutaneously monitored and plotted on a timeline graph every 5 s. The maximal IAP and the area under the IAP curve exceeding 10 mmHg (AUC≥10 mmHg) were compared between groups, with the agreement between IAP and endolumenally monitored ILP also analyzed for animals in the SPACE group.

RESULTS

In the first study, 8 mmHg was identified as the most preferable preset pressure after establishment of the perforation. In the randomized study, the mean maximal IAP in the SPACE group was significantly lower than that in the manual insufflation group (11.0 ± 2.0 mmHg vs. 17.0 ± 3.5 mmHg; P = 0.03). The mean AUC≥10 mmHg was also significantly smaller in the SPACE group. Bland-Altman analysis demonstrated agreement between IAP and ILP within a range of ± 1.0 mmHg.

CONCLUSIONS

SPACE could be used to control and safely monitor IAP during gastric EFTR by measuring ILP during perforation of the gastric wall.

Endoscopic Submucosal Dissection of Gastric Neoplastic Lesions: An Italian, Multicenter Study

Endoscopic submucosal dissection (ESD) allows removing neoplastic lesions on gastric mucosa, including early gastric cancer (EGC) and dysplasia. Data on ESD from Western countries are still scanty. We report results of ESD procedures performed in Italy. Data of consecutive patients who underwent ESD for gastric neoplastic removal were analyzed. The en bloc resection rate and the R0 resection rates for all neoplastic lesions were calculated, as well as the curative rate (i.e., no need for surgical treatment) for EGC. The incidence of complications, the one-month mortality, and the recurrence rate at one-year follow-up were computed. A total of 296 patients with 299 gastric lesions (80 EGC) were treated. The en bloc resection was successful for 292 (97.6%) and the R0 was achieved in 266 (89%) out of all lesions. In the EGC group, the ESD was eventually curative in 72.5% (58/80) following procedure. A complication occurred in 30 (10.1%) patients. Endoscopic treatment was successful in all 3 perforations, whereas it failed in 2 out of 27 bleeding patients who were treated with radiological embolization (1 case) or surgery (1 case). No procedure-related deaths at one-month follow-up were observed. Lesion recurrence occurred in 16 (6.2%) patients (6 EGC and 10 dysplasia). In conclusion, the rate of both en bloc and R0 gastric lesions removal was very high in Italy. However, the curative rate for EGC needs to be improved. Complications were acceptably low and amenable at endoscopy.

Endoscopic imaging techniques for detecting early colorectal cancer

PURPOSE OF REVIEW

The detection of early colorectal cancer has improved notably since the introduction of bowel cancer screening programmes. This has created new challenges from endoscopic, histological and therapeutic perspectives. Here, we outline the limitations of current clinical practice and ways of implementing optical diagnosis to overcome these limitations.

RECENT FINDINGS

Virtual chromoendoscopy without magnification for predicting or ruling out deep submucosal invasion is useful in real clinical practice for most lesions. However, magnifying virtual chromoendoscopy is needed to make an accurate diagnosis in nonulcerated narrow-band imaging international colorectal endoscopic (NICE) type 3 lesions or NICE type 2 lesions with depressed areas or of nodular mixed type. Finally, dye-based magnifying chromoendoscopy is needed in Japanese NBI Expert Team 2B lesions assessed with magnifying virtual chromoendoscopy.

SUMMARY

A four-step strategy is proposed, combining white-light assessment, virtual chromoendoscopy without magnification, virtual chromoendoscopy with magnification and dye-based chromoendoscopy with magnification.

Endoscopic submucosal dissection for suspected early gastric cancer: absolute versus expanded criteria in a large Western cohort (with video)

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is an effective, minimally invasive, surgery-sparing technique for the treatment of early gastric cancer (EGC). It is not well established whether EGC within the Japanese expanded criteria can be safely and effectively treated using ESD in the West. We describe the outcomes of ESD for endoscopically suspected, biopsy specimen-confirmed EGC and its adenomatous precursor lesions (pEGC) using the Vienna classification of dysplasia in a Western cohort.

METHODS

Prospective data were collected on all pEGCs undergoing ESD at a single expert endoscopy center. Outcomes were compared among pEGC, satisfying the Japanese absolute and expanded criteria, those outside criteria, and those specimens that contained low-grade dysplasia (LGD) only. Specialist GI pathologists reviewed and classified all ESD specimens. Patients were followed up at 6 and 12 months.

RESULTS

Over 71 months, 135 pEGCs in 121 patients (mean age, 72.0 years; 61.2% men) underwent ESD. Median pEGC size was 20 mm (interquartile range, 15-30), and 62 (45.9%) satisfied the expanded clinical criteria. Perforation occurred in 1.5% and postprocedural bleeding in 5.2%. Forty-two pEGCs (31.1%) contained LGD only. Rates of en bloc and R0 resection were 94.8% and 86.7%, respectively. One hundred seven pEGCs (79.2%) met the absolute or expanded criteria for endoscopic cure. Two pEGCs recurred during follow-up. Ten of 26 patients with pEGC (38.5%) outside criteria for cure underwent surgery after ESD with residual tumor detected in 3 specimens. Fifteen patients with outside criteria for pEGCs did not undergo surgery because of frailty or their expressed wish. Eleven of 15 patients have so far undergone first surveillance with 1 of 11 experiencing endoscopic and histologic recurrence.

CONCLUSIONS

ESD is a safe and effective treatment for pEGCs in a Western context. Patients who either decline or are too frail for surgery, with outside criteria resections, may benefit from ESD for local disease control. Large Western studies of ESD for pEGCs are required to define long-term patient outcomes and surveillance guidelines, particularly where pathology shows LGD or high-grade dysplasia only. (Clinical trial registration number: NCT02306707.).

Mucin phenotype of differentiated early gastric cancer: an immunohistochemistry study supporting therapeutic decision making

Introduction: Endoscopic submucosal dissection is widely employed in early gastric cancer (EGC). Foveolar phenotypes should be distinguished from the other differentiated EGC (DEGC) types because of their increased malignant potential. The phenotypic classification could be useful not only for investigating EGC tumorigenesis but also for evaluating the tumor aggressiveness to guide treatment decision making. Methods: On surgical tissue specimens, we studied the mucin phenotype of EGC to distinguish cases with a worse prognosis dictating different therapeutic options or a very close surveillance program. DEGC in our series were classified as mucin foveolar (51%) or mucin intestinal (49%) phenotype. We evaluated correlations among foveolar and intestinal phenotypic markers, tumor patterns, clinicopathologic features and prognostic and therapeutic implications. Immunohistochemistry (IHC) for MUC5AC and CDX2 was performed on 63 EGC patient specimens. MUCA5C was employed as gastric foveolar phenotypic marker and CDX2 as intestinal phenotypic marker. Results: Foveolar DEGC was significantly associated with larger tumor size (p=0.01), high grade (G2-G3) (p=0.001), vessel permeation (p=0.05), lymph node metastasis (p=0.001) and ulceration (p=0.001), whereas intestinal type DEGC was associated with low grade (p=0.001). Conclusion: IHC determination of the mucin phenotype is an easy, inexpensive method that can provide useful, sensitive markers distinguishing the foveolar or intestinal phenotype in DEGC. The precise identification of the foveolar type, featuring a poorer prognosis, should sound a warning bell mandating very close study of the lesion before endoscopic treatment or contraindicating endoscopic resection in favor of the open surgery option.

Endoscopic foregut surgery and interventions: The future is now. The state-of-the-art and my personal journey

In this paper, I reviewed the emerging field of endoscopic surgery and present data supporting the contention that endoscopy can now be used to treat many foregut diseases that have been traditionally treated surgically. Within each topic, the content will progress as follows: "lessons learned", "technical considerations" and "future opportunities". Lessons learned will provide a brief background and update on the most current literature. Technical considerations will include my personal experience, including tips and tricks that I have learned over the years. Finally, future opportunities will address current unmet needs and potential new areas of development. The foregut is defined as "the upper part of the embryonic alimentary canal from which the pharynx, esophagus, lung, stomach, liver, pancreas, and part of the duodenum develop". Foregut surgery is well established in treating conditions such as gastroesophageal reflux disease (GERD), achalasia, esophageal diverticula, Barrett's esophagus (BE) and esophageal cancer, stomach cancer, gastric-outlet obstruction, and obesity. Over the past decade, remarkable progress in interventional endoscopy has culminated in the conceptualization and practice of endoscopic foregut surgery for various clinical conditions summarized in this paper. Regarding GERD, there are now several technologies available to effectively treat it and potentially eliminate symptoms, and the need for long-term treatment with proton pump inhibitors. For the first time, fundoplication can be performed without the need for open or laparoscopic surgery. Long-term data going out 5-10 years are now emerging showing extended durability. In respect to achalasia, per-oral endoscopic myotomy (POEM) which was developed in Japan, has become an alternative to the traditional Heller's myotomy. Recent meta-analysis show that POEM may have better results than Heller, but the issue of post-POEM GERD still needs to be addressed. There is now a resurgence of endoscopic treatment of Zenker's diverticula with improved technique (Z-POEM) and equipment; thus, patients are choosing flexible endoscopic treatment as opposed to open or rigid endoscopy options. In regard to BE, endoscopic submucosal dissection (ESD) which is well established in Asia, is now becoming more mainstream in the West for the treatment of BE with high grade dysplasia, as well as early esophageal cancer. In combination with all the ablation technologies (radiofrequency ablation, cryotherapy, hybrid argon plasma coagulation), the entire spectrum of Barrett's and related dysplasia and early cancer can be managed predominantly by endoscopy. Importantly, in regard to early gastric cancer and submucosal tumors (SMTs) of the stomach, ESD and full thickness resection (FTR) can excise these lesions en-bloc and endoscopic suturing is now used to close large defects and perforations. For treatment of patients with malignant gastric outlet obstruction (GOO), endoscopic gastro-jejunostomy is now showing better results than enteral stenting. G-POEM is also emerging as a treatment option for patients with gastroparesis. Obesity has become an epidemic in many western countries and is becoming also prevalent in Asia. Endoscopic sleeve gastroplasty (ESG) is now becoming an established treatment option, especially for obese patients with body mass index between 30 and 35. Data show an average weight loss of 16 kg after ESG with long-term data confirming sustainability. Finally, in respect to endo-hepatology, there are many new endoscopic interventions that have been developed for patients with liver disease. Endoscopic ultrasound (EUS)-guided liver biopsy and EUS-guided portal pressure measurement are exciting new frontiers for the endo-hepatologists.

AGA Institute Clinical Practice Update: Endoscopic Submucosal Dissection in the United States

Endoscopic submucosal dissection (ESD) is an established endoscopic resection method in Asian countries, which is increasingly practiced in Europe and by early adopters in the United States for removal of early cancers and large lesions from the luminal gastrointestinal tract. The intent of this expert review is to provide an update regarding the clinical practice of ESD with a particular focus on its use in the United States. This review is framed around the 16 best practice advice points agreed upon by the authors, which reflect landmark and recent published articles in this field. This expert review also reflects our experience as advanced endoscopists with extensive experience in performing and teaching others to perform ESD in the United States. Best Practice Advice 1: Endoscopic submucosal dissection should be recognized as a mature endoscopic technique that enables complete removal of lesions that are too large for en bloc endoscopic mucosal resection or are at increased risk of containing cancer. Best Practice Advice 2: The safety and feasibility of endoscopic submucosal dissection for early gastric cancer is well established. The absolute indications for curative endoscopic resection include moderately and well-differentiated, nonulcerated, mucosal lesions that are ≤2 cm in size. Best Practice Advice 3: Other relative (expanded) indications for gastric endoscopic submucosal dissection include moderately and well-differentiated superficial cancers that are >2 cm, lesions ≤3 cm with ulceration or that contain early submucosal invasion, and poorly differentiated superficial cancers ≤2 cm in size. The risk of lymph node metastasis when endoscopic submucosal dissection is performed for these indications is higher than when it is performed for absolute indications but remains acceptably low. Best Practice Advice 4: Endoscopic submucosal dissection may be considered in selected patients with Barrett's esophagus with the following features: large or bulky area of nodularity, lesions with a high likelihood of superficial submucosal invasion, recurrent dysplasia, endoscopic mucosal resection specimen showing invasive carcinoma with positive margins, equivocal preprocedural histology, and intramucosal carcinoma. Best Practice Advice 5: Endoscopic submucosal dissection is the primary modality for treatment of squamous cell dysplasia and cancer confined to the superficial esophageal mucosa. Any degree of submucosal invasion caries an increased risk of lymph node metastasis and alternative/additional therapy should be considered. Best Practice Advice 6: Duodenal endoscopic submucosal dissection is associated with an increased risk of intraprocedural perforation and delayed adverse events. Duodenal endoscopic submucosal dissection should be limited to endoscopists with extensive experience in performing endoscopic submucosal dissection in other locations. It is strongly suggested that endoscopists in the United States refrain from performing duodenal endoscopic submucosal dissection during the early phase of their endoscopic submucosal dissection practice. Best Practice Advice 7: All colorectal lesions should be evaluated for suitability for endoscopic resection. Accumulating evidence has shown that the majority of colorectal neoplasms without signs of deep submucosal invasion or advanced cancer can be treated by advanced endoscopic resection techniques. Best Practice Advice 8: Colorectal neoplasms containing dysplasia confined to the mucosa have no risk for lymph node metastasis and endoscopic resection should be considered as the criterion standard. Best Practice Advice 9: Large (>2 cm) colorectal lesions frequently (>43%) require piecemeal removal when endoscopic mucosal resection is used, which is associated with increased (up to 20%) rates of recurrent neoplasia. Endoscopic submucosal dissection enables higher rates of en bloc resection and lower recurrence rates for these lesions. Patients with large complex colorectal polyps should be referred to a high-volume, specialized center for endoscopic removal by endoscopic mucosal resection or endoscopic submucosal dissection. Best Practice Advice 10: Endoscopic resection for colorectal lesions offers significant cost benefit compared with surgery, and case-based endoscopic submucosal dissection selection for high-risk lesions could offer cost savings. Best Practice Advice 11: Endoscopists in the United States embarking on performing endoscopic submucosal dissection should be familiar with currently available endoscopic tissue closure devices. Both clip closure and endoscopic suturing techniques have been shown to be effective in managing intraprocedural perforation. Complete closure of a post-endoscopic submucosal dissection site may be considered in certain circumstances based on patient factors, procedural factors, and the location of the lesion. Best Practice Advice 12: Careful coagulation of exposed blood vessels in the resection site may reduce the risk of delayed bleeding after endoscopic submucosal dissection. The use of low-voltage coagulation current is recommended for this technique. Best Practice Advice 13: Endoscopists should affix the endoscopic submucosal dissection specimen to a flat surface (eg, pin the specimen to cork board) and immerse it in formalin. An expert gastrointestinal pathologist should evaluate the specimen for margin involvement, degree of differentiation, presence or absence of lymphovascular invasion, depth of submucosal invasion (if present), and tumor budding. Best Practice Advice 14: Acquiring high-level competency in endoscopic submucosal dissection is achievable in the United States. Alternative educational models should be used in the United States because of the limited number of experts and the differing prevalence of gastrointestinal luminal diseases as compared with Asia. Best Practice Advice 15: The endoscopic submucosal dissection educational model most suited for the current environment in the United States is a stepwise approach consisting of didactic self-study, attending training courses with increasing levels of complexity, self-practice on animal models, and observation of live cases performed by experts. Endoscopists should perform their initial endoscopic submucosal dissections on patients with lesions that have well-established indications for endoscopic submucosal dissection and are of the lowest technical complexity. Best Practice Advice 16: Endoscopists in the United States who perform endoluminal resection should educate referring physicians to avoid practices that may induce submucosal fibrosis hampering future endoscopic mucosal resection or endoscopic submucosal dissection. These practices include tattooing in close proximity to or beneath a lesion for marking and partial snare resection of a portion of a lesion for histopathology.

Epstein-Barr Virus-associated Early Gastric Cancer Treated with Endoscopic Submucosal Dissection: A Possible Candidate for Extended Criteria of Endoscopic Submucosal Dissection

A 73-year-old man visited our hospital for the treatment of an early gastric cancer (GC) lesion. We performed en bloc resection using endoscopic submucosal dissection (ESD) for his GC lesion. The present GC lesion was Epstein-Barr virus (EBV)-associated poorly differentiated-type adenocarcinoma invading into the submucosal layer. Recently, accumulating data has shown that the risk of lymph node metastasis from early EBV GC without local lymphovascular infiltration is low. The present patient has been in good health for over three years since ESD. Some cases of early EBV GC with invasion into the submucosal layer may be candidates for further extension of the ESD criteria.

Introduction of endoscopic submucosal dissection in the West

Endoscopic submucosal dissection (ESD) is well established in Asia as a modality for selected advanced lesions of both the upper and lower gastrointestinal tract, but ESD has not attained the same niche in the West due to a variety of reasons. These include competition from traditional surgery, minimally invasive surgery and endoscopic mucosal resection. Other obstacles to ESD introduction in the West include time commitment for learning and doing procedures, a steep learning curve, special equipment, lack of mentors, cost issues, interdisciplinary conflicts, concern regarding complications and lack of support from institutions and interfacing departments. There are intrinsic differences in pathology prevalence (e.g., early gastric cancer) between the two regions that are less conducive for ESD implementation in the West. We will elaborate on these issues and suggest measures as well as a protocol to overcome these obstacles and hopefully allow introduction of ESD as a tenable option for appropriate patients.

Management of Early-Stage Adenocarcinoma of the Esophagus: Endoscopic Mucosal Resection and Endoscopic Submucosal Dissection

Barrett's esophagus with high-grade dysplasia and early-stage adenocarcinoma is amenable to curative treatment by endoscopic resection. Histopathological correlation has established that mucosal cancer has minimal risk of nodal metastases and that long-term complete remission can be achieved. Although surgery is the gold-standard treatment once there is submucosal involvement, even T1sm1 (submucosal invasion ≤ 500 μm) cases without additional risk factors for nodal metastases might also be cured with endoscopic resection. Endoscopic resection is foremost an initial diagnostic procedure, and once histopathological assessment confirms that curative criteria are met, it will be considered curative. Endoscopic resection may be achieved by endoscopic mucosal resection, which, although easy to perform with relatively low risk, is limited by an inability to achieve en bloc resection for lesions of size more than 1.5 cm. Conversely, the technique of endoscopic submucosal dissection is more technically demanding with higher risk of complications but is able to achieve en bloc resection for lesions larger than 1.5 cm. Endoscopic submucosal dissection would be particularly important in specific situations such as suspected submucosal invasion and lesion size more than 1.5 cm. In other situations, since endoscopic resection would always be combined with radiofrequency ablation to ablate the remaining Barrett's epithelium, piecemeal endoscopic mucosal resection would suffice since any remnant superficial invisible dysplasia would be ablated.