A comparison of outcomes of endoscopic submucosal dissection (ESD) For early gastric neoplasms between high-volume and low-volume centers: multi-center retrospective questionnaire study conducted by the Nagano ESD Study Group

Predictors of long-term outcomes of endoscopic submucosal dissection of early gastric neoplasia in the West: a multicenter study

BACKGROUND

This study aimed to determine long-term outcomes of gastric endoscopic submucosal dissection (ESD) in Western settings based on the latest Japanese indication criteria, and to examine predictors of outcomes and complications.

METHODS

Data were collected from consecutive patients undergoing gastric ESD at four participating centers from 2009 to 2021. Retrospective analysis using logistic regression and survival analysis was performed.

RESULTS

415 patients were included (mean age 71.7 years; 56.4 % male). Absolute indication criteria (2018 guideline) were met in 75.3 % of patients. Median follow-up was 52 months. Post-resection histology was adenocarcinoma, high grade dysplasia, and low grade dysplasia in 49.9 %, 22.7 %, and 17.1 %, respectively. Perforation, early and delayed bleeding occurred in 2.4 %, 4.3 %, and 3.4 %, respectively. Rates of en bloc and R0 resection, and recurrence on first endoscopic follow-up were 94.7 %, 83.4 %, and 2.7 %, respectively. Relative indication (2018 guideline) for ESD was associated with R1 outcome (P = 0.02). Distal location (P = 0.002) and increased procedure time (P = 0.04) were associated with bleeding, and scarring (P = 0.009) and increased procedure duration (P = 0.003) were associated with perforation. Recurrence-free survival at 2 and 5 years was 94 % and 83 %, respectively.

CONCLUSION

This is the largest Western multicenter cohort and suggests that gastric ESD is safe and effective in the Western setting. A quarter of patients fell outside the new absolute indications for ESD, suggesting that Western practice involves more advanced lesions. We identified the predictors of complications, which should help to inform future Western practice and research.

Training in Endoscopic Submucosal Dissection in the United States: The Current Paradigm

Endoscopic submucosal dissection (ESD) training in Japan is pursued through a designated master-apprentice, organ-based stepwise training model. However, applying a similar program to the United States is not a practical strategy due to the significant differences in the training system and disease prevalence. To incorporate the ESD training into the current advanced endoscopy fellowship program, the use of recently developed techniques and technologies to improve the efficiency of ESD is ideal. The ESD training program in the United States should be prevalence-based, with increased involvement of trainees depending on their objectively assessed competency levels.

Influence of hospital volume on bleeding after endoscopic submucosal dissection for early gastric cancer in Japan: a multicenter propensity score-matched analysis

BACKGROUND

Information on whether there is a relationship between hospital volume and bleeding after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) is limited. This study aimed to compare the bleeding rates after ESD for EGC according to the hospital volume.

METHODS

Patients who underwent ESD for EGC at 33 institutions in Japan between November 2013 and October 2016 were included in this multicenter retrospective study. Hospital volume was categorized into three groups, based on the average annual number of ESD procedures: low- and medium-volume group (LMVG), high-volume group (HVG), and very high-volume group (VHVG). The bleeding rate after ESD for EGC was compared between the three hospital volume groups after propensity score matching.

RESULTS

A total of 10,320 patients, including 2797 patients in the LMVG, 4646 patients in the HVG, and 2877 patients in the VHVG, were identified. Propensity score matching yielded 2002 patients in each hospital volume group, with an improved balance of confounding variables between the three groups. The bleeding rates in the LMVG, HVG, and VHVG were 4.3%, 3.7%, and 4.9%, respectively, and no significant difference was noted between the three groups.

CONCLUSIONS

The bleeding rate after ESD for EGC did not differ between hospitals in Japan. The finding indicated that ESD for EGC is equally feasible across Japanese hospitals of different volumes regarding bleeding after ESD.

Endoscopic Submucosal Dissection in Europe: Results of 1000 Neoplastic Lesions From the German Endoscopic Submucosal Dissection Registry

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) enables the curative resection of early malignant lesions and is associated with reduced recurrence risk. Due to the lack of comprehensive ESD data in the West, the German ESD registry was set up to evaluate relevant outcomes of ESD.

METHODS

The German ESD registry is a prospective uncontrolled multicenter study. During a 35-month period, 20 centers included 1000 ESDs of neoplastic lesions. The results were evaluated in terms of en bloc, R0, curative resection rates, and recurrence rate after a 3-month and 12-month follow-up. Additionally, participating centers were grouped into low-volume (≤20 ESDs/y), middle-volume (20-50/y), and high-volume centers (>50/y). A multivariate analysis investigating risk factors for noncurative resection was performed.

RESULTS

Overall, en bloc, R0, and curative resection rates of 92.4% (95% confidence interval [CI], 0.90-0.94), 78.8% (95% CI, 0.76-0.81), and 72.3% (95% CI, 0.69-0.75) were achieved, respectively. The overall complication rate was 8.3% (95% CI, 0.067-0.102), whereas the recurrence rate after 12 months was 2.1%. High-volume centers had significantly higher en bloc, R0, curative resection rates, and recurrence rates and lower complication rates than middle- or low-volume centers. The lesion size, hybrid ESD, age, stage T1b carcinoma, and treatment outside high-volume centers were identified as risk factors for noncurative ESD.

CONCLUSION

In Germany, ESD achieves excellent en bloc resection rates but only modest curative resection rates. ESD requires a high level of expertise, and results vary significantly depending on the center's yearly case volume.

Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer (second edition)

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society, in collaboration with the Japanese Gastric Cancer Association, produced "Guidelines for Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection for Early Gastric Cancer" in 2014, as a set of basic guidelines in accordance with the principles of evidence-based medicine. At the time, a number of statements had to be established by consensus (the lowest evidence level), as evidence levels remained low for many specific areas in this field. However, in recent years, the number of well-designed clinical studies has been increasing. Based on new findings, we have issued the revised second edition of the above guidelines that cover the present state of knowledge. These guidelines are divided into the following seven categories: indications, preoperative diagnosis, techniques, evaluation of curability, complications, long-term postoperative surveillance, and histology.

Current state of education and training for endoscopic submucosal dissection: Translating strategy and success to the USA

Endoscopic submucosal dissection (ESD) is a rigorous and technically sophisticated method for removal of lesions within the gastrointestinal tract. Despite having advantages of en-bloc resection of lesions, regardless of size, and widespread use in Japan and Asia, ESD has not become widely adopted in the USA for a variety of reasons. Based upon Japanese education and the master-apprentice model, modification to the education system and additional techniques designed to facilitate broader adoption are required for trainees in the USA. This article will review the current state of education and training for ESD in the USA.

Risk factors of lymph node metastasis or lymphovascular invasion for early gastric cancer: a practical and effective predictive model based on international multicenter data

Background

Most lymph node metastasis (LNM) models for early gastric cancer (EGC) include lymphovascular invasion (LVI) as a predictor. However, LVI must be confirmed by postoperative pathology. In this study, we aimed to develop a model for predicting the risk of LNM/LVI in EGC using preoperative factors.

Methods

EGC patients who underwent radical gastrectomy at Fujian Medical University Union Hospital and Sun Yat-sen University Cancer Center (n = 1460) were selected as the training set. The risk factors of LNM/LVI were investigated. Data from the International study group on Minimally Invasive surgery for GASTRIc Cancer trial (n = 172) were selected as the validation set.

Results

In the training set, the incidence of LNM/LVI was 21.6%. The 5-year cancer-specific survival rates of patients with and without LNM/LVI were 92.4 and 95.0%, respectively, with significant difference (P = 0.030). Multivariable logistic regression analysis showed that the four independent risk factors for LNM/LVI were female, tumor larger than 20 mm, submucosal invasion and undifferentiated tumor histological type (all P <  0.05); the area under the curve (AUC) was 0.694 (95% confidence interval [CI]: 0.659–0.730). Patients were divided into low-risk, intermediate-risk, high-risk and extremely high-risk groups by recursive partitioning analysis; the incidences of LNM/LVI were 5.4, 12.6, 24.2 and 37.8%, respectively (P <  0.001). The AUC of the validation set was 0.796 (95%CI, 0.662–0.851) and the predictive performance of the LNM/LVI risk in the validation set was consistent with that in the training set.

Conclusions

The risk of LNM/LVI in differentiated mucosal EGC is low, which indicated that endoscopic resection is a treatment option. The risk of LNM/LVI in undifferentiated mucosal EGC and submucosa EGC are high and gastrectomy with lymph node dissection is suggested.

How to Learn and Perform Endoscopic Submucosal Dissection and Full-Thickness Resection in the Colorectum in the United States

Pioneered in Japan to address the limitations of endoscopic mucosal resection in the stomach, endoscopic submucosal dissection (ESD) has been applied throughout the gastrointestinal tract, including the colorectum. ESD is technically challenging and has been slowly gaining traction in the West. However, for the committed and resourceful endoscopist, proficiency in ESD can still be achieved. Moreover, improvement in techniques and devices are likely to ease the learning curve while improving procedural duration, safety, and efficacy of colorectal ESD. This article reviews challenges and methods in learning ESD in the United States and provides a primer on performing ESD and full-thickness resection in the colorectum.

Randomized Controlled Trial Comparing the Effects of Vonoprazan Plus Rebamipide and Esomeprazole Plus Rebamipide on Gastric Ulcer Healing Induced by Endoscopic Submucosal Dissection

Objective Gastric endoscopic submucosal dissection (ESD) is currently a standard procedure, and proton pump inhibitors (PPIs) are most commonly used to treat post-ESD ulcers. Vonoprazan, a potassium-competitive acid blocker (P-CAB), reportedly inhibits gastric acid secretions more effectively than PPIs. Combination therapy of a PPI plus rebamipide is effective for treating larger ulcers. Our goal was to evaluate the effects of vonoprazan plus rebamipide compared to esomeprazole plus rebamipide for the treatment of post-ESD ulcers. Methods First, vonoprazan plus rebamipide (V group) or esomeprazole plus rebamipide (E group) was orally administered to subjects for eight weeks. We then evaluated the ulcer healing process at four and eight weeks after the procedure using a gastric ulcer stage system and by measuring the ulcer size. Patients A total of 84 patients who underwent ESD for gastric neoplasms between September 2015 and December 2017 in Tsuchiura Kyodo General Hospital were included in this randomized controlled trial. Results The ulcer scar rates at week 4 in the V group (n=43) and E groups (n=39) were 20.9% and 15.4%, while those at week 8 were 90.7% and 92.3%, respectively. The ulcer reduction rates at week 4 in the V and E groups were 94.6% and 93.8%, and those at week 8 were 99.7% and 99.3%, respectively. The ulcer scar rates and reduction rates were not significantly different between the two groups. Conclusion Combination therapy consisting of vonoprazan plus rebamipide was not superior to that of esomeprazole plus rebamipide for post-ESD ulcer healing (UMIN000019516).

Wide-field endoscopic mucosal resection versus endoscopic submucosal dissection for laterally spreading colorectal lesions: a cost-effectiveness analysis

OBJECTIVE

To compare the cost-effectiveness of endoscopic submucosal dissection (ESD) and wide-field endoscopic mucosal resection (WF-EMR) for removing large sessile and laterally spreading colorectal lesions (LSLs) >20 mm.

DESIGN

An incremental cost-effectiveness analysis using a decision tree model was performed over an 18-month time horizon. The following strategies were compared: WF-EMR, universal ESD (U-ESD) and selective ESD (S-ESD) for lesions highly suspicious for containing submucosal invasive cancer (SMIC), with WF-EMR used for the remainder. Data from a large Western cohort and the literature were used to inform the model. Effectiveness was defined as the number of surgeries avoided per 1000 cases. Incremental costs per surgery avoided are presented. Sensitivity and scenario analyses were performed.

RESULTS

1723 lesions among 1765 patients were analysed. The prevalence of SMIC and low-risk-SMIC was 8.2% and 3.1%, respectively. Endoscopic lesion assessment for SMIC had a sensitivity and specificity of 34.9% and 98.4%, respectively. S-ESD was the least expensive strategy and was also more effective than WF-EMR by preventing 19 additional surgeries per 1000 cases. 43 ESD procedures would be required in an S-ESD strategy. U-ESD would prevent another 13 surgeries compared with S-ESD, at an incremental cost per surgery avoided of US$210 112. U-ESD was only cost-effective among higher risk rectal lesions.

CONCLUSION

S-ESD is the preferred treatment strategy. However, only 43 ESDs are required per 1000 LSLs. U-ESD cannot be justified beyond high-risk rectal lesions. WF-EMR remains an effective and safe treatment option for most LSLs.

TRIAL REGISTRATION NUMBER

NCT02000141.

Endoscopic submucosal dissection in the West: Current status and future directions

Endoscopic submucosal dissection (ESD) was first conceptually described almost 30 years ago in Japan and is now widely practiced throughout East Asia. ESD expands the boundaries of endoscopic resection (ER) by allowing en bloc resection of large early neoplastic lesions within the gastrointestinal tract (GIT). This offers advantages over other ER techniques by facilitating definitive histological staging and curative treatment of early cancer in selected cases. Indeed, the experience of ESD in Eastern countries is significant, and excellent outcomes from high-volume centers are reported. The potential benefits of ESD are recognized by Western endoscopists, but its adoption has been limited. A number of factors contribute to this, including epidemiological differences in GIT neoplasia between Western and Eastern populations and limitations in training opportunities. In this review, we discuss the role of ESD, its current status and the future in Western endoscopic practice.

Long-Term Clinical Efficacy and Perioperative Safety of Endoscopic Submucosal Dissection versus Endoscopic Mucosal Resection for Early Gastric Cancer: An Updated Meta-Analysis

BACKGROUND

To systematically evaluate the safety and efficacy of endoscopic submucosal dissection (ESD) versus endoscopic mucosal resection (EMR) for early gastric cancer (EGC).

METHODS

We searched the databases of PubMed, Web of Science, EMBASE, and the Cochrane Library from January 2000 to April 2017 and included studies that compared the outcomes of ESD with EMR for EGC. These eligible studies that met the inclusion criteria were screened out and were assessed by two independent investigators.

RESULT

In total, 18 retrospective cohort studies were eligible for analysis. Our results indicated that ESD is more beneficial than EMR in increasing the complete resection rate and en bloc resection rate and decreasing the local recurrence rate. However, ESD prolonged operative time and increased incidence of gastric perforation than EMR. No differences were found in postoperative bleeding rate between the two approaches.

CONCLUSION

Compared with EMR, ESD offers higher complete resection rate, higher en bloc resection rate, and lower local recurrence rate but has prolonged operative time and increased incidence of gastric perfusion. There is no statistical difference in the rate of postoperative bleeding between the two groups. However, the above conclusion needs further verification by well-designed, randomized trials with larger samples and long follow-up periods.

Effects of esomeprazole on the healing process of post-endoscopic submucosal dissection gastric ulcers: a single arm, prospective trial

Objectives: Gastric endoscopic submucosal dissection (ESD) is currently a standard procedure. ESD enables en-bloc resection of large lesions, while inducing larger artificial ulcers to a greater extent than conventional procedures. Several studies have reported that proton pump inhibitors (PPIs) prevent delayed bleeding and expedite the artificial ulcer healing process. Esomeprazole, an S-isomer of omeprazole, is reportedly one of strongest inhibitors of gastric acid secretion. Previous studies have examined the effectiveness of esomeprazole. Our goal was to verify the effects of esomeprazole on artificial ulcers in a prospective study.

Methods: A total of 185 patients underwent ESD for gastric neoplasms at our hospital between January 2013 and June 2015. Among these 185 patients, 49 post-ESD scar lesions were included in this prospective trial. First, 20 mg esomeprazole was orally administered to all subjects before and after the procedure. We then evaluated the delayed bleeding rate and ulcer scarring rates at 4 weeks and 8 weeks after the procedure by using a gastric ulcer stage system.

Results: There was one case of delayed bleeding (2.0%). Regardless of Helicobacter pylori infection status, ulcer scarring rates at weeks 4 and 8 were respectively 28.6% (14/49) and 98% (48/49).

Conclusions: Our results suggest that oral administration of esomeprazole alone may be sufficient for prompt healing of artificial gastric ulcers induced by ESD (UMIN000009367).

Endoscopic Submucosal Dissection Outcomes for Gastroesophageal Tumors in Low Volume Units: A Multicenter Survey

Background and Aims. Endoscopic submucosal dissection (ESD) outcomes have traditionally been reported from high volume centers in East Asia. Data from low volume centers in other parts of Asia remain sparse. Methods. A retrospective survey with a structured questionnaire of 5 tertiary centers in 3 countries in South East Asia was conducted. Details of training and clinical outcomes of ESD cases, with follow-up data from these centers, were analyzed. Results. Seven endoscopists from the 5 centers performed a total of 35 cases of ESD in the upper gastrointestinal tract (UGIT) over a 6-year duration. Details of the lesions excised were as follows: median size was 20 mm, morphologically 20 (68.6%) were flat/depressed and 6 (17.1%) were submucosal, and histologically 27 (77.1%) were neoplastic. The median duration of ESD procedures was 105 minutes, with an en-bloc resection rate of 91.4%. There was 1 (2.9%) case of delayed bleeding, but no perforation nor mortality in any of the cases. The recurrence rate after ESD was 5.7%. A prolonged ESD duration was influenced by a larger size of lesion (25 mm, p = 0.02) but not by factors related to the training experience of endoscopists. Conclusions. ESD in the UGIT is feasible and safe in low volume centers in Asia.

The expansion of endoscopic submucosal dissection in France: A prospective nationwide survey

INTRODUCTION

Early reports of endoscopic submucosal dissection (ESD) in Europe suggested high complication rates and disappointing outcomes compared to publications from Japan. Since 2008, we have been conducting a nationwide survey to monitor the outcomes and complications of ESD over time.

MATERIAL AND METHODS

All consecutive ESD cases from 14 centers in France were prospectively included in the database. Demographic, procedural, outcome and follow-up data were recorded. The results obtained over three years were compared to previously published data covering the 2008-2010 period.

RESULTS

Between November 2010 and June 2013, 319 ESD cases performed in 314 patients (62% male, mean (±SD) age 65.4 ± 12) were analyzed and compared to 188 ESD cases in 188 patients (61% male, mean (±SD) age 64.6 ± 13) performed between January 2008 and October 2010. The mean (±SD) lesion size was 39 ± 12 mm in 2010-2013 vs 32.1 ± 21 for 2008-2010 (p = 0.004). En bloc resection improved from 77.1% to 91.7% (p < 0.0001) while R0 en bloc resection remained stable from 72.9% to 71.9% (p = 0.8) over time. Complication rate dropped from 29.2% between 2008 and 2010 to 14.1% between 2010 and 2013 (p < 0.0001), with bleeding decreasing from 11.2% to 4.7% (p = 0.01) and perforations from 18.1% to 8.1% (p = 0.002) over time. No procedure-related mortality was recorded.

CONCLUSIONS

In this multicenter study, ESD achieved high rates of en bloc resection with a significant trend toward better outcomes over time. Improvements in lesion delineation and characterization are still needed to increase R0 resection rates.

Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society (JGES), in collaboration with the Japanese Gastric Cancer Association (JGCA), has produced 'Guidelines for ESD and EMR for Early Gastric Cancer', as a set of basic guidelines in accordance with the principles of evidence-based medicine. These Guidelines cover the present state of knowledge and are divided into the following seven categories: Indications, Preoperative diagnosis, Techniques, Evaluation of curability, Complications, Long-term postoperative surveillance, and Histology. Twenty-three statements were finally accepted as guidelines, and the majority of these were obtained from descriptive studies with lower evidence levels. A number of statements had to be created by consensus (the lowest evidence level), as evidence levels remain low for many specific areas in this field.

Endoscopic Submucosal Dissection for Early Gastric Cancer: Getting It Right!

Endoscopic resection is a widely accepted less-invasive treatment technique for local resection of early gastric cancer (EGC) lesions with a negligible risk of lymph node metastasis. Remarkable progress has been made during the last decade in this field, both in terms of expansion of the indications (to larger lesions and to lesions with ulceration) and in terms of technical improvements from endoscopic mucosal resection (EMR) to endoscopic submucosal dissection (ESD). Previously, larger lesions and lesions with ulceration were resected surgically because of the difficulty in effectively using EMR in this context. ESD however allows a high rate of en bloc resections, regardless of tumor location, tumor size, or the presence of ulceration. Nonetheless, ESD also has drawbacks: the procedure time is increased, ESD is more technically challenging compared to EMR, and, finally, ESD is associated with a slightly higher risk of complications. In order to overcome these limitations and minimize complications, a step-by-step process is important for learning ESD techniques. This chapter addresses the indications, results, some technical tips, and complications of ESD for EGC.

Therapeutic outcomes of endoscopic submucosal dissection of differentiated early gastric cancer in a Western endoscopy setting (with video)

BACKGROUND

Large multicenter gastric cancer endoscopic submucosal dissection (ESD) studies conducted at major Japanese institutions have reported en bloc resection, en bloc tumor-free margin resection, and curative resection rates of 92.7% to 96.1%, 82.6% to 94.5%, and 73.6% to 85.4%, respectively, with delayed bleeding and perforation rates of 0.6% to 6.0% and 3.6% to 4.7%, respectively. Although ESD is currently an alternative treatment in some countries, particularly in Asia, it remains uncertain whether ESD therapeutic outcomes in Western endoscopy settings can be comparable to those achieved in Japan.

OBJECTIVE

To evaluate the ESD therapeutic outcomes for differentiated early gastric cancer (EGC) in a Western endoscopy setting.

DESIGN/SETTING

Consecutive case series performed by an expertly trained Western endoscopist.

PATIENTS

Fifty-three patients with 54 lesions.

INTERVENTIONS

ESD for early gastric cancers (T1) satisfying expanded inclusion criteria.

MAIN OUTCOME MEASUREMENTS

En bloc resection, en bloc tumor-free margin resection, and curative resection rates were 98%, 93%, and 83%, respectively. The delayed bleeding rate was 7%, and the perforation rate was 4%.

RESULTS

The mean patient age was 67 years, and the mean tumor size was 19.8 mm, with 54% of the lesions located in the lesser curvature. The median procedure time was 61 minutes, with ESD procedures 60 minutes or longer associated with submucosal fibrosis (P < .001) and tumor size 25 mm or larger (P = .03). In every ESD procedure, both circumferential incision and submucosal dissection were performed by using a single knife. Two of the 4 delayed bleeding cases required surgery, and all perforations were successfully managed by using endoscopic clips.

LIMITATION

Long-term outcome data are currently unavailable.

CONCLUSION

ESD for differentiated EGC resulted in favorable therapeutic outcomes in a Western endoscopy setting comparable to those achieved at major Japanese institutions.

Endoscopic resection of gastric and esophageal cancer

Endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) techniques have reduced the need for surgery in early esophageal and gastric cancers and thus has lessened morbidity and mortality in these diseases. ESD is a relatively new technique in western countries and requires rigorous training to reproduce the proficiency of Asian countries, such as Korea and Japan, which have very high complete (en bloc) resection rates and low complication rates. EMR plays a valuable role in early esophageal cancers. ESD has shown better en bloc resection rates but it is easier to master and maintain proficiency in EMR; it also requires less procedural time. For early esophageal adenocarcinoma arising from Barrett’s, ESD and EMR techniques are usually combined with other ablative modalities, the most common being radiofrequency ablation because it has the largest dataset to prove its success. The EMR techniques have been used with some success in early gastric cancers but ESD is currently preferred for most of these lesions. ESD has the added advantage of resecting into the submucosa and thus allowing for endoscopic resection of more aggressive (deeper) early gastric cancer.

Current status and scope of lymph node micrometastasis in gastric cancer

Recently, lymph node micrometastasis has been evaluated for its prognostic value in gastric cancer. Lymph node micrometastasis cannot be detected via a usual pathologic examination, but it can be detected by using some other techniques including immunohistochemistry and reverse transcription-polymerase chain reaction assay. With the development of such diagnostic techniques, the detection rate of lymph node micrometastasis is constantly increasing. Although the prognostic value of lymph node micrometastasis remains debatable, its clinical impact is apparently remarkable in both early and advanced gastric cancer. At present, studies on the prognostic value of lymph node micrometastasis are evolving to overcome its current limitations and extend the scope of its application.

Endoscopic treatment for early gastric cancer

Gastric cancer remains one of the most common causes of cancer death. However the proportion of early gastric cancer (EGC) at diagnosis is increasing. Endoscopic treatment for EGC is actively performed worldwide in cases meeting specific criteria. Endoscopic mucosal resection can treat EGC with comparable results to surgery for selected cases. Endoscopic submucosal dissection (ESD) increases the en bloc and complete resection rates and reduces the local recurrence rate. ESD has been performed with expanded indication and is expected to be more widely used in the treatment of EGC through the technological advances in the near future. This review will describe the techniques, indications and outcomes of endoscopic treatment for EGC.

Effect of recombinant human VEGF165b protein and bevacizumab on expression of CD34 and cell apoptosis in human gastric carcinoma xenografts in nude mice

AIM: To investigate the effect of recombinant human VEGF₁₆₅b protein (rhVEGF₁₆₅b) and bevacizumab on expression of CD34 and cell apoptosis in human gastric carcinoma xenografts in nude mice.

METHODS: Thirty male nude mice were used to establish the human gastric carcinoma xenograft model. The mice were randomly divided into three groups: a rhVEGF₁₆₅b group (intraperitoneal injection, 10 μg/kg), a bevacizumab group (intraperitoneal injection, 5 mg/kg) and a control group. Tumor growth was detected by measuring tumor volume and weight. The expression of CD34 and apoptosis of tumor cells were detected by immunohistochemistry and TdT-mediated dUTP nick end labeling (TUNEL) assay at weeks 1, 2 and 3, respectively.

RESULTS: Tumor volume and weight at weeks 1 and 2 in the rhVEGF₁₆₅b group (week 1: 0.546 ± 0.132 vs 0.637 ± 0.084, 1.894 ± 0.599 vs 0.46 ± 0.093; week 2: 1.894 ± 0.599 vs 2.238 ± 0.29, 1.537 ± 0.568 vs 2.013 ± 0.833; P < 0.05 for all) and at weeks 1, 2 and 3 in the bevacizumab group (week 1: 0.453 ± 0.119 vs 0.637 ± 0.084, 0.320 ± 0.097 vs 0.460 ± 0.093; week 2: 1.691 ± 0.381 vs 2.238 ± 0.290, 1.168 ± 0.524 vs 2.013 ± 0.833; week 3: 1.709 ± 0.474 vs 4.872 ± 0.594, 1.747 ± 0.557 vs 3.463 ± 0.986, P < 0.05 for all) were significantly smaller than those in the control group. At week 3, tumor volume and weight were significantly larger in the rhVEGF₁₆₅b group than in the bevacizumab group (3.843 ± 1.339 vs 1.709 ± 0.474, 3.066 ± 1.281 vs 1.747 ± 0.557, P < 0.05 for both). Microvascular density (MVD) and apoptosis index (AI) at weeks 1, 2 and 3 in the rhVEGF₁₆₅b group and bevacizumab group were significantly different from those in the control group. MVD and AI also differed significantly between the rhVEGF₁₆₅b group and bevacizumab group.

CONCLUSION: Both rhVEGF₁₆₅b and bevacizumab can inhibit the growth of human gastric carcinoma cells possibly by inhibiting angiogenesis and inducing apoptosis, with rhVEGF₁₆₅b having a more significant effect in early stage.

Prediction of submucosal gastric cancer by narrow-band imaging magnifying endoscopy

BACKGROUND

The features of gastric submucosal cancer revealed by magnifying endoscopy have not been reported. Aim of our study was to investigate whether magnifying endoscopy could contribute to the diagnosis of submucosal invasion.

PATIENTS AND METHODS

In this prospective, cross-sectional study, 197 lesions of gastric differentiated adenocarcinoma, diagnosed as mucosal cancer by conventional endoscopy, were observed by magnifying endoscopy with narrow-band imaging, paying attention to the presence of a blurry mucosal pattern and an irregular mesh pattern. After endoscopic submucosal dissection, all lesions were examined histologically and the areas of two features were estimated.

RESULTS

Among the lesions examined, 177 were diagnosed histologically as mucosal cancer and 20 as submucosal cancer. Multivariate logistic regression analysis confirmed that a blurry mucosal pattern (odds ratio 12.15, 95% confidence interval 3.45-42.76, p=0.000) and an irregular mesh pattern (22.55, 4.22-120.45, p=0.000) were independent predictors of submucosal invasion.

CONCLUSIONS

Narrow band imaging magnifying endoscopic features are useful for predicting submucosal invasion in gastric cancer.

Expression of ST13 and HSP70 in gastric polyps and gastric cancer

AIM: To detect the expression of suppression of tumorigenicity13 (ST13) and heat shock protein70 (HSP70) in gastric polyps and gastric cancer and to analyze their correlation.

METHODS: Immunohistochemistry was used to detect the expression of ST13 and HSP70 in 30 cases of normal gastric mucosa, 30 cases of gastric polyps, 16 cases of gastric adenomatous polyps, and 30 cases of gastric carcinoma. The correlation between expression of ST13 and HSP70 in gastric polyps and gastric carcinoma was analyzed.

RESULTS: The rank mean for HSP70 expression in normal gastric mucosa, hyperplastic polyps, adenomatous polyps, gastric carcinoma was 32.35, 40.47, 63.25, and 82.48, respectively, showing a gradually decreasing trend (P < 0.01). The rank mean for expression of STl3 in normal gastric mucosa, hyperplastic polyps, adenomatous polyps, and gastric carcinoma group was 68.25, 59.77, 44.91 and 37.07, respectively, showing a gradually increasing trend. HSP70 and ST13 expression was negatively correlated in both adenomatous polyps and gastric cancer.

CONCLUSION: HSP70 protein expression shows an increasing trend and ST13 protein expression shows a decreasing trend in gastric carcinogenesis, suggesting that HSP70 and ST13 are closely related to the formation of gastric cancer. There is a negative correlation between HSP70 protein and ST13 protein expression in gastric adenomatous polyps and gastric carcinoma, suggesting that they may interact with each other.

Complications of gastric endoscopic submucosal dissection

Endoscopic resection is now a widely accepted treatment for early gastric cancer, having a negligible risk of lymph-node metastasis. Endoscopic submucosal dissection (ESD) is a relatively new endoscopic resection method developed in the mid-1990 s that facilitates en-bloc resection even in patients with large or ulcerative lesions difficult to resect using conventional endoscopic mucosal resection (EMR). However, compared to EMR, ESD requires a longer procedure time and a higher level of technical expertise, in addition to having a slightly greater risk of complications. Endoscopists must be aware of not only the risk factors for, and incidence of, complications, but also how to effectively treat such complications. Perforation and bleeding are the major complications associated with gastric ESD. The perforation and delayed bleeding rates have been reported to range from 1.2% to 5.2% and 0% to 15.6%, respectively, and can usually be managed with appropriate endoscopic treatment. Immediate bleeding during gastric ESD is quite common and controlling such bleeding, which is primarily achieved by carrying out electrocautery, plays a critical role in the successful completion of ESD.

The current state of diagnosis and treatment for early gastric cancer

The prognosis for gastric cancer depends on its stage; so, detection in the early stage of disease is important, when complete and curative removal is possible. Accurate diagnosis can be facilitated by a sound understanding of the basic findings of white light endoscopy of early gastric cancer, and diagnosis can be refined further by the combined use of other imaging modalities such as image-enhanced endoscopy including chromoendoscopy and endoscopic ultrasonography. Minimally invasive endoscopic treatment has come to be the preferred therapeutic approach for early gastric cancer. In addition to conventional endoscopic mucosal resection, a new technique known as endoscopic submucosal dissection (ESD) has spread rapidly worldwide. Indeed, strategies for ESD have been established, devices developed, its indications expanded, and its safety and long-term results extensively reported. Some unique combination therapies involving endoscopy and surgical treatment have also been reported. It is anticipated that the number of patients undergoing endoscopic therapy will continue to increase, and the ongoing developments in endoscopic treatment are expected not only to improve gastric cancer prognosis but also to maintain good quality of life after treatment.

Endoscopic submucosal dissection--current success and future directions

More than 10 years have passed since endoscopic submucosal dissection (ESD) was first developed in Japan. ESD enables en bloc complete resection of superficial gastrointestinal neoplasms regardless of the size and location of the lesions. With improvements in techniques and devices, excellent therapeutic results have been achieved despite the inherent technical difficulties of this procedure. ESD aiming for curative treatment can be performed for gastrointestinal neoplasms without risk of lymph node metastasis. Accurate histopathologic examination of the resected specimen is required to determine the risk of lymph node metastasis, for which en bloc resection is beneficial. Owing to the high success rate of en bloc complete resection and accurate histopathologic examination, tumour recurrence rates after ESD are reported to be very low in Japan. Excellent results of ESD in a large number of cases have also been reported from other Asian countries such as South Korea, Taiwan and China. Although scepticism exists among Western clinicians regarding the application of ESD, it is developing slowly and reports indicate promising results in some European countries. With further development of technologies, such as endoscopic robotics, ESD could become the worldwide treatment of choice for early gastrointestinal neoplasms.

Factors predicting perforation during endoscopic submucosal dissection for gastric cancer

BACKGROUND

Perforation is a common complication of endoscopic submucosal dissection (ESD), but little is known about the relevant risk factors.

OBJECTIVE

To investigate the risk factors for perforation.

DESIGN

Retrospective study.

SETTING

A cancer referral center.

PATIENTS

A total of 1795 early gastric tumors in 1500 patients treated by ESD from July 2002 to December 2010 were included in the analysis.

MAIN OUTCOME MEASUREMENTS

The associations between the incidence of perforation and patient and lesion characteristics were investigated.

RESULTS

Perforation during ESD occurred in 50 lesions (2.8%). Univariate analysis identified tumor location (upper, middle, or lower stomach), tumor diameter (≤ 20 or >20 mm), and treatment period (lesions treated in the first or second period) as predictors of perforation. Multivariate analysis identified tumor location (upper stomach), tumor diameter (>20 mm), and treatment period (first half) as independent risk factors for perforation. The odds ratios were 2.4 (95% CI, 1.3-4.7; P = .006) for lesions in the upper stomach and 1.9 (95% CI, 1.0-3.5; P = .04) for lesions larger than 20 mm. Perforation risks were 5.4% for lesions in the upper stomach and 4.4% for lesions larger than 20 mm. Three patients required emergency surgery, but the rest of the patients were successfully treated with endoscopic clipping. There was no perforation-related mortality.

LIMITATIONS

Single-center, retrospective study design.

CONCLUSIONS

Lesions in the upper stomach and lesions larger than 20 mm were independent risk factors for perforation during ESD. Patients should be made aware of the estimated high risks of these lesions before undergoing ESD.

Utility and problems of endoscopic submucosal dissection for early gastric cancer in elderly patients

BACKGROUND AND AIM

Endoscopic submucosal dissection (ESD) is reported to be a safe and reliable procedure for the elderly, but these reports could have already had a bias at the time ESD was performed. However, the reports have not clearly stated the criteria of indications. In the present study, we retrospectively elucidated the usefulness and problems of ESD for early gastric cancer in elderly patients (≥ 65 years) in comparison with non-elderly patients.

METHODS

The subjects were selected from 412 consecutive patients with early gastric cancer (515 lesions) for which ESD was performed between June 2002 and February 2010. The following were used for analysis between groups: pre- and postoperative performance status (PS) of subjects, prevalence rates of pre-existing comorbidities, characteristics of lesions, treatment outcomes, durations of hospitalization, operating times, incidence rates of complications and durations of hospitalization, and postoperative hemorrhage rates, and duration of hospitalization in patients with anticoagulant therapy.

RESULTS

Of the lesions in the elderly, four patients (1.0%) were elderly with a PS of 3. The PS increased to six patients (1.6%) after the procedure. None of the non-elderly had a PS of 3 before or after the procedure. The ratio of patients with a pre-existing comorbidity was higher in the elderly than in the non-elderly. There were no differences between the two groups in the characteristics of the lesions, their duration of hospitalization, their operating times, or the incidence rates of complications. However, the elderly with perforations had a significantly longer hospitalization than the comparable non-elderly. The percentage of the patients taking anticoagulant drugs was significantly higher among the elderly. Of the patients on anticoagulant therapy, the duration of hospitalization tended to be longer in the elderly but no significant difference was found. None of the non-elderly with postoperative hemorrhage had received anticoagulant therapy. In the elderly with postoperative hemorrhage, 15.8% of the lesions were in those who had received anticoagulant therapy, indicating a significantly higher percentage of such lesions in the elderly group.

CONCLUSION

We conclude that ESD is useful in elderly patients because there is a similar risk as for the non-elderly if the approach is individualized, and the following are taken into consideration when making the final decision of performing ESD in an elderly patient: patients should have a PS of 0, 1, or 2; determine whether or not anticoagulant therapy can be discontinued and whether or not treatment can be performed reliably without complications.

Impact of endoscopic submucosal dissection for the therapeutic strategy of large colorectal tumors

BACKGROUND AND AIMS

The change of therapeutic strategy for large colorectal tumors after the introduction of endoscopic submucosal dissection (ESD) has not yet been clarified. The aim of this study was to estimate the impact of ESD as an initial treatment strategy.

METHODS

A questionnaire was administered to nine expert panelists in colorectal ESD. The questionnaire used retrospective data from consecutive case series. Forty-seven cases of early colorectal tumors (≥ 20 mm) were included. Endoscopic growth types were 25 laterally-spreading tumors (LST) of granular type (G), 15 LST of non-granular types (NG), and seven protruded types. Pathological diagnoses included 15 adenomas (Ad), 18 intramucosal cancers (M), three submucosally-shallow invasive cancers (< 1000 µm) (SMs), and 11 submucosally-deep invasive cancers (≥ 1000 µm) (SMd). The expert panelists completed questionnaires about recommended initial treatment under suppositions of before and after the introduction of ESD. Over-surgery was defined as surgery for Ad, M, and SMs. Non-curative endoscopic resection (ER) was defined as ER for SMd.

RESULTS

After the introduction of ESD, the reduction in the over-surgery rate was estimated at 10.8% for Ad, M, and SMs, and the increase in the non-curative ER rate was estimated at 27.2% for SMd. By endoscopic growth type, the reduction of over-surgery rates for LST-NG, LST-G, and protruded type was 15.5%, 10.5%, and 2.2%, respectively.

CONCLUSIONS

The endoscopists changed their therapeutic strategy for large colorectal tumors to reduce over-surgery, especially in LST-NG, demonstrating the impact of ESD.

Two years' intensive training in endoscopic diagnosis facilitates detection of early gastric cancer

OBJECTIVE

Early detection of gastric cancer by screening endoscopy facilitates endoscopic treatment in place of open surgery. The aim of this study was to evaluate whether 2 years intensive training improved the detection of gastric cancer by screening endoscopy.

METHODS

An endoscopist who had trained for 6 years as a general physician, performed screening endoscopy at Imari Arita Kyoritsu Hospital before (group I) and after (group II) intensive training in the diagnosis of early gastric cancer in consecutive patients.

RESULTS

Background characteristics, including age (61.6 vs. 62.2 years) and sex, did not differ between the groups. Before training, 10 gastric neoplasms were detected in 937 patients in group I: four early gastric cancers, one gastric adenoma, and five advanced gastric cancer. After training, 36 gastric neoplasms were detected in 937 patients in group II: 18 early gastric cancers, 11 gastric adenoma, five advanced gastric cancer, and one each of gastric carcinoid and malignant lymphoma. The detection rate for early gastric cancer was significantly improved by training [group I: 4/937 (0.4%) vs. group II: 18/937 (1.9%)], although the detection rate for advanced gastric cancer did not differ before and after training. The proportion of early gastric cancer + adenoma to advanced cancer was higher in group II (5/5 vs. 29/5 in group I).

CONCLUSION

Intensive training in upper gastrointestinal endoscopy screening dramatically improved the detection rate for early gastric cancer, although the detection rate for advanced gastric cancer was not affected.

The effectiveness and safety of endoscopic submucosal dissection compared with endoscopic mucosal resection for early gastric cancer: a systematic review and metaanalysis

BACKGROUND

Endoscopic submucosal dissection (ESD) allows en bloc resection of the entire lesion, permitting a higher curative resection rate and increased quality of life by minimizing the resection size compared with that of endoscopic mucosal resection (EMR). Although ESD has been implemented at most university hospitals in Korea, potential complications of ESD such as bleeding and perforation raise doubts in the therapeutic decision on use of the ESD procedure for early gastric cancer patients and in reimbursement decision making. This systematic review aimed to address both the effectiveness and safety outcomes of ESD versus EMR for early gastric cancer.

METHODS

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL), and Koreamed were searched using the primary keywords "stomach neoplasm" AND "endoscopic submucosal dissection" AND "endoscopic mucosal resection." To assess the quality of selected studies, the methodologic approach of the Scottish Intercollegiate Guidelines Network was used. Five effectiveness-relevant and three safety-relevant outcome measures were extracted. Bibliography management and metaanalysis for each outcome were conducted using Review Manager 5.0.

RESULTS

Three nonconcurrent cohort studies and nine retrospective cohort studies were identified. Metaanalyses showed ESD to be significantly more effective than EMR for en bloc resection (odds ratio [OR], 8.43; 95% confidence interval [CI], 5.20-13.67), complete resection (OR, 14.11; 95% CI, 10.85-18.35), curative resection (OR, 3.28; 95% CI, 1.95-5.54), and local recurrence (risk ratio [RR], 0.13; 95% CI, 0.04-0.41). Whereas intraoperative bleeding (RR, 2.16; 95% CI, 1.14-4.09), perforation risk (RR, 3.58; 95% CI, 1.95-6.55), and operation time (standard mean difference [SMD], 1.55; 95% CI, 0.74-2.37) were significantly greater for ESD, overall bleeding risk (RR, 1.22; 95% CI, 0.76-1.98) and all-cause mortality (RR, 0.65; 95% CI, 0.08-5.38) did not differ significantly between ESD and EMR.

CONCLUSIONS

Considering that bleeding risk did not differ significantly between ESD and EMR and that perforation risk usually does not lead to life-threatening disease, the effectiveness benefit of ESD can outweigh the overall harm compared with EMR on the condition that ESD is performed by experienced practitioners.