Long-term outcome of early gastric cancer after endoscopic submucosal dissection: expanded indication is comparable to absolute indication

Role of second look endoscopy in endoscopic submucosal dissection and peptic ulcer bleeding: Meta-analysis of randomized controlled trials

BACKGROUND

Second-look endoscopy (SLE) to prevent recurrent bleeding in patients with peptic ulcer disease (PUD) and those undergoing endoscopic submucosal dissection (ESD) is routinely being performed. Conflicting evidence exists regarding efficacy, risk, benefit, and cost-effectiveness.

AIM

To identify the role and effectiveness of SLE in ESD and PUD, associated rebleeding and PUD-related outcomes like mortality, hospital length of stay, need for endoscopic or surgical intervention and blood transfusions.

METHODS

A systematic review of literature databases PubMed, Cochrane, and Embase was conducted from inception to January 5, 2023. Randomized controlled trials that compared patients with SLE to those who did not have SLE or evaluated the role of prophylactic hemostasis during SLE compared to other conservative interventions were included. The study was conducted per PRISMA guidelines, and the protocol was registered in PROSPERO (ID CRD42023427555:). RevMan was used to perform meta-analysis, and Mantel-Haenszel Odds ratio (OR) were generated using random effect models.

RESULTS

A total of twelve studies with 2687 patients were included in our systematic review and meta-analysis, of which 1074 patients underwent SLE after ESD and 1613 patients underwent SLE after PUD-related bleeding. In ESD, the rates of rebleeding were 7% in the SLE group compared to 4.4% in the non-SLE group with OR 1.65, 95% confidence intervals (CI) of 0.96 to 2.85; P = 0.07, whereas it was 11% in the SLE group compared to 13% in the non-SLE group with OR 0.8 95%CI: 0.50 to 1.29; P = 0.36. The mean difference in the blood transfusion rates in the SLE and no SLE group in PUD was OR 0.01, 95%CI: -0.22 to 0.25; P = 0.91. In SLE vs non-SLE groups with PUD, the OR for Endoscopic intervention was 0.29, 95%CI: 0.08 to 1.00; P = 0.05 while it was OR 2.03, 95%CI: 0.95 to 4.33; P = 0.07, for surgical intervention. The mean difference in the hospital length of stay was -3.57 d between the SLE and no SLE groups in PUD with 95%CI: -7.84 to 0.69; P = 0.10, denoting an average of approximately 3 fewer days of hospital stay among patients with PUD who underwent SLE. For mortality between SLE and non-SLE groups in PUD, the OR was 0.88, 95%CI: 0.45 to 1.72; P = 0.70.

CONCLUSION

SLE does not confer any benefit in preventing ESD and PUD-associated rebleeding. SLE also does not provide any significant improvement in mortality, need for interventions, or blood transfusions in PUD patients. SLE decreases the hospital length of stay on average by 3.5 d in PUD patients.

Comparison of endoscopic submucosal dissection versus surgery for early gastric cancer in the elderly: a pooled analysis

PURPOSE

The aim of this study was to investigate whether there was a difference in overall survival (OS) between elderly patients with early gastric cancer (EGC) who underwent endoscopic submucosal dissection (ESD) and those who underwent surgery.

METHODS

Four databases including PubMed, Embase, the Cochrane Library and CKNI were searched on March 20, 2023. The characteristics of the studies and the baseline information of the patients, including their medical histories, postoperative data, and prognoses, were recorded. Odds ratios (ORs) or mean differences (MDs), and 95% confidence intervals (CIs) were pooled up to calculate baseline information and postoperative information. Hazard ratios (HRs) and 95% CIs were used to calculate the prognosis of the patients. Stata V16.0 software was used for the data analysis.

RESULTS

A total of eight studies involving 2334 patients were included for the data analysis in this study. After pooling up the data, we found that the ESD group had lower Eastern Cooperative Oncology Groupprevious (ECOG) scores (OR = 0.33, 95% CI = 0.17 to 0.65, I2 = 59.69%, P = 0.00 < 0.05) than the surgery group. There were significant differences in the operation time (MD = -3.38, 95% CI = -5.19 to -1.57, I2 = 98.31%, P = 0.00 < 0.05), length of hospital stay (MD = -3.01, 95% CI = -4.81 to -1.20, I2 = 98.83%, P = 0.00 < 0.05) and hospitalization expenses (MD = -2.67, 95% CI = -3.59 to -1.75, I2 = 93.21%, P = 0.00 < 0.05) between the two groups. The ESD group had a lower OS rate (HR = 2.81, 95% CI = 2.20 to 3.58, I2 = 12.28%, P = 0.00 < 0.05).

CONCLUSION

Elderly patients with EGC who underwent ESD had a significantly worse OS rate than those who underwent surgery. If the patient's condition was suitable, surgery was still recommended for these patients.

Clinical and endoscopic features of metachronous gastric cancer with possible lymph node metastasis after endoscopic submucosal dissection and Helicobacter pylori eradication

BACKGROUND

Several studies have reported the metachronous gastric cancers (MGCs) with possible lymph node metastasis (LNM) after endoscopic submucosal dissection (ESD) and Helicobacter pylori (H. pylori) eradication in which a curative ESD had not been achieved. There have been no published reports of evaluations of the features of patients with MGC with possible LNM after ESD and H. pylori eradication.

METHODS

We identified 264 patients with 369 MGCs after H. pylori eradication among the 4354 patients with 5059 early gastric cancers (EGCs) who underwent ESD between 1999 and 2017 and divided them into two groups: patients with MGCs with possible LNM (Group I) and patients with MGCs undergone curative ESD (Group II). We retrospectively compared the features of patients with MGCs and patients with EGCs at index ESD in the two groups.

RESULT

Group I consisted of 20 patients with 21 MGCs, and Group II consisted of 244 patients with 348 MGCs. Group I lesions were significantly more common in the posterior wall than in the lesser curvature (odds ratio [OR] = 3.97; 95% confidence intervals [CI] 1.20-13.10). Development of Group I was significantly more common in patients with a body mass index (BMI) < 19.0 kg/m2 than in patients with a BMI ≥ 19.0 kg/m2 at index ESD (OR = 4.44; 95% CI 1.30-15.20).

CONCLUSIONS

During surveillance endoscopy after gastric ESD and H. pylori eradication, the posterior wall should be carefully examined to detect MGCs early. Lower BMI may be associated with the development of MGCs with possible LNM.

A 6-year nationwide population-based study on the current status of gastric endoscopic resection in Korea using administrative data

Gastric endoscopic resection (ER) is widely performed in Korea. This study aimed to investigate the overall status of gastric ER in Korea. We enrolled ESD or EMR cases performed for gastric cancer and adenoma from 2012 to 2017 by searching the NHIS database. The annual trend of gastric ER and the clinical characteristics were investigated. Institutions were classified into very high-, high-, low-, and very low volume centers (VHVC, HVC, LVC, and VLVC) by the procedure numbers, and institutional types, regional distributions, and medical resources were investigated accordingly. There were 175,370 ER cases during the study period, with an increasing trend over time. The average annual ESD procedure numbers were 3.9, 54.5, 249.5, and 540.3 cases in 131 VLVCs, 119 LVCs, 24 HVCs, and 12 VHVCs, respectively. Among ESD-performing institutions, 44.8% were located in the Seoul Capital Area. The distribution of medical resources showed a positive correlation with the procedural volume. Similar tendencies were also demonstrated in EMR, with some differences in hospital types and regional distribution. Gastric ER and ESD are increasing in Korea. There was a significant variance in the number of ER procedures and the distribution of types, regions, and medical resources according to the procedural volume.

Long-term Survival After Endoscopic Resection For Gastric Cancer: Real-world Evidence From a Multicenter Prospective Cohort

BACKGROUND & AIMS

We aimed to clarify the long-term outcomes of endoscopic resection (ER) for early gastric cancers (EGCs) based on pathological curability in a multicenter prospective cohort study.

METHODS

We analyzed the long-term outcomes of 9054 patients with 10,021 EGCs undergoing ER between July 2010 and June 2012. Primary endpoint was the 5-year overall survival (OS). The hazard ratio for all-cause mortality was calculated using the Cox proportional hazards model. We also compared the 5-year OS with the expected one calculated for the surgically resected patients with EGC. If the lower limit of the 95% confidence interval (CI) of the 5-year OS exceeded the expected 5-year OS minus a margin of 5% (threshold 5-year OS), ER was considered to be effective. Pathological curability was categorized into en bloc resection, negative margins, and negative lymphovascular invasion: differentiated-type, pT1a, ulcer negative, ≤2 cm (Category A1); differentiated-type, pT1a, ulcer negative, >2 cm or ulcer positive, ≤3 cm (Category A2); undifferentiated-type, pT1a, ulcer negative, ≤2 cm (Category A3); differentiated-type, pT1b (SM1), ≤3 cm (Category B); or noncurative resections (Category C).

RESULTS

Overall, the 5-year OS was 89.0% (95% CI, 88.3%-89.6%). In a multivariate analysis, no significant differences were observed when the hazard ratio of Categories A2, A3, and B were compared with that of A1. In all the pathological curability categories, the lower limit of the 95% CI for the 5-year OS exceeded the threshold 5-year OS.

CONCLUSION

ER can be recommended as a standard treatment for patients with EGCs fulfilling Category A2, A3, and B, as well as A1 (UMIN Clinical Trial Registry, UMIN000005871).

Endoscopic Resection of Undifferentiated Early Gastric Cancer

Endoscopic resection (ER) is widely performed for early gastric cancer (EGC) with a negligible risk of lymph node metastasis (LNM) in Eastern Asian countries. In particular, endoscopic submucosal dissection (ESD) leads to a high en bloc resection rate, enabling accurate pathological evaluation. As undifferentiated EGC (UD-EGC) is known to result in a higher incidence of LNM and infiltrative growth than differentiated EGC (D-EGC), the indications for ER are limited compared with those for D-EGC. Previously, clinical staging as intramucosal UD-EGC ≤2 cm, without ulceration, was presented as 'weakly recommended' or 'expanded indications' for ER in the guidelines of the United States, Europe, Korea, and Japan. Based on promising long-term outcomes from a prospective multicenter study by the Japan Clinical Oncology Group (JCOG) 1009/1010, the status of this indication has expanded and is now considered 'absolute indications' in the latest Japanese guidelines published in 2021. In this study, which comprised 275 patients with UD-EGC (cT1a, ≤2 cm, without ulceration) treated with ESD, the 5-year overall survival (OS) was 99.3% (95% confidence interval, 97.1%-99.8%), which was higher than the threshold 5-year OS (89.9%). Currently, the levels of evidence grades and recommendations for ER of UD-EGC differ among Japan, Korea, and Western countries. Therefore, a further discussion is warranted to generalize the indications for ER of UD-EGC in countries besides Japan.

The Efficacy of a Novel Type of Integrated Knife for Endoscopic Submucosal Dissection in Early Gastric Cancer

Background/Aims: This study aimed to compare the efficacy of a recently developed clear-cut knife with that of widely used knives for endoscopic submucosal dissection (ESD) in early gastric cancer (EGC).Materials and Methods: Data were collected retrospectively from the National Health Insurance Service Ilsan Hospital between May 2017 and April 2019. The study included 105 patients (108 lesions) with EGC who underwent ESD. Fifty-six EGCs were dissected using an insulation-tipped diathermic knife in combination with a needle knife, while 52 EGCs were dissected using a clear-cut knife, a single device with an integrated needle and an insulated-tipped knife. Oncologic outcomes and technical success were compared between the two groups.Results: The distribution of the tumor locations, composition of the undifferentiated types of EGCs, and the size of EGCs (14.3±8.0 vs. 16.6±7.3 mm; P=0.130) were not significantly different between the groups. The complete (98.2% vs. 94.2%; P=0.273) and curative (87.5% vs. 88.5%; P=0.878) resection rates were not statistically different. Furthermore, no significant difference between the total procedure times (39±34.1 vs. 35.7±20.1 minutes; P=0.554), areas of the dissected specimen (858.6±406.5 vs. 980.3±393.8 mm2; P=0.119) and dissected areas per minute (32.4±17.9 vs. 35.5±16.2 mm²/min; P=0.345) were noted. Regarding complications, the overall perforation rates (3.6% vs. 4.0%) and bleeding rates (3.6% vs. 8.0%) were not statistically different.Conclusions: The newly developed clear-cut knife is as useful as the combination of classical knives for ESD in EGC.

Long-term outcomes of endoscopic submucosal dissection and surgery for undifferentiated intramucosal gastric cancer regardless of size

BACKGROUND

The clinical outcomes of endoscopic submucosal dissection (ESD) for undifferentiated (UD) intramucosal early gastric cancer (EGC) compared with those of surgery, regardless of lesion size, are not well known. Furthermore, there is a concern regarding the treatment plan before and after ESD in cases of UD intramucosal EGC within expanded indications.

AIM

To evaluate clinical outcomes of ESD compared with those of surgery in UD intramucosal EGC patients regardless of tumor size.

METHODS

We enrolled patients with UD intramucosal EGC after ESD with complete resection or surgery from January 2005 to August 2020 who met the within or beyond expanded indications with lesion size > 2 cm (the only non-curative factor). Overall, 123 and 562 patients underwent ESD and surgery, respectively. After propensity-score matching, clinical and long-term outcomes, i.e., recurrence-free survival (RFS) and overall survival (OS), were analyzed. The multivariable Cox proportional hazard model with treatment modality and ESD indication was used to evaluate the recurrence risk.

RESULTS

After matching, 119 patients each were finally enrolled in the ESD and surgery groups. The median length of hospital stay was shorter in the ESD group than surgery group (4.0 vs 9.0 days, P < 0.001). Four cases of recurrence after ESD were local recurrences, all of which occurred within 1 year. Total recurrence was seven (5.9%) and two (1.7%) in the ESD and surgery groups, respectively. No difference was observed between the two groups with respect to OS (P = 0.948). However, the ESD group had inferior RFS compared with the surgery group (P = 0.031). ESD was associated with the risk of recurrence after initial treatment in all enrolled patients (hazard ratio, 5.2; 95% confidence interval: 1.0-25.8, P = 0.045).

CONCLUSION

Although OS was similar between the two groups, surveillance endoscopy was important for the ESD than for the surgery group because RFS was inferior and local recurrence was an issue.

Quantifying early gastric cancer in Australia: What is the opportunity for gastric endoscopic submucosal dissection?

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is the recommended treatment for early gastric cancer (EGC). However, there are challenges in attaining expertise in ESD in countries where the incidence of gastric cancer and proportion diagnosed at an early stage of disease are relatively low. This study aims to establish the proportion of gastric cancer meeting histological criteria for EGC, which may be suitable for ESD, in a Western population.

METHODS

Gastric cancers reported to the Victorian Cancer Registry between January 2011 and December 2016 were analyzed. EGC was defined as tumor confined to mucosa (T1a) or submucosa (T1b). Histology reports were analyzed using Japanese and European guidelines to identify potential ESD candidates. Criteria for extended ESD were based on grade of differentiation, tumor depth, lymphovascular and perineural invasion, and ulceration.

RESULTS

Twenty percent of 1217 gastric cancers was EGC (237 cases), with detailed histopathology reports suitable for evaluating ESD criteria recorded in 182 cases. Standard and extended ESD criteria were met in 46% (84/182) and 75% (132/182), respectively. Actual treatment of the 237 EGC was endoscopic in 14% (n = 33) and surgery in 86% (n = 204). Endoscopically treated EGCs were more likely to be stage T1a and located in the proximal stomach.

CONCLUSIONS

EGCs represented 20% of reported gastric adenocarcinomas with the majority fulfilling criteria for ESD. ESD should be considered in the management algorithm and discussed at tumor board meetings involving interventional endoscopists. To increase utilization of ESD, systems need to be implemented to improve training, accreditation, and access to ESD.

Impact of non-curative endoscopic submucosal dissection on short- and long-term outcome of subsequent laparoscopic gastrectomy for pT1 gastric cancer

BACKGROUND

The feasibility and oncological safety of non-curative endoscopic submucosal dissection (ESD) prior to additional gastrectomy for early gastric cancer (EGC) are still unclear. The aim of this study was to evaluate the impact of non-curative ESD on short- and long-term outcomes of subsequent laparoscopic gastrectomy (LG) for pathological T1 (pT1) EGC.

METHODS

We retrospectively investigated 422 patients who underwent LG for pT1 EGC between January 2007 and December 2017 at our center. Eighty-five of these patients underwent ESD with curative intent before surgery. Using propensity-score matching for sex, age, body mass index, American society of anesthesiologists score, history of previous abdominal surgery, tumor location, mucosal/submucosal infiltration, histology, lymph node metastasis, extent of lymph node dissection, operative method, lymphatic invasion, and venous invasion, the clinicopathologic and survival data of these patients were compared.

RESULTS

The median follow-up period was 60 (range 2-168) months. Using propensity-score matching from a total of 422 patients, 75 patients were selected in the Non-ESD and the ESD cohorts each. There were no significant differences in terms of characteristics and clinicopathological findings between the two groups. Furthermore, there were no significant differences in postoperative morbidity (13.3% vs. 17.3%; P = 0.497) and mortality (1.3% vs. 0%; P = 0.316). Both the 5-year overall survival ratio (88.8% vs. 86.9%; P = 0.757) and 5-year disease-specific survival ratio (97.1% vs. 98.4%; P = 0.333) were similar in the two groups.

CONCLUSION

Short- and long-term outcomes of LG in patients with pT1 EGC are not related to preoperative ESD history. Even for non-curative resections, ESD prior to surgery is feasible in terms of oncological and surgical outcomes in pT1 EGC.

Endoscopic Submucosal Dissection versus Surgery for Undifferentiated-Type Early Gastric Cancer: A Systematic Review and Meta-Analysis

Background/Aims

The use of endoscopic submucosal dissection (ESD) for treating undifferentiated-type early gastric cancer is controversial. The objective of this study was to perform a meta-analysis to compare the long-term outcomes of ESD and surgery for undifferentiated-type early gastric cancer.

Methods

The PubMed, Cochrane Library, and EMBASE databases were used to search for relevant studies comparing ESD and surgery for undifferentiated-type early gastric cancer. The methodological quality of the included publications was evaluated using the Risk of Bias Assessment tool for Nonrandomized Studies. The rates of overall survival, recurrence, adverse event, and complete resection were determined. Odds ratios (ORs) and 95% confidence intervals (CIs) were also evaluated.

Results

This meta-analysis enrolled five studies with 429 and 1,236 participants undergoing ESD and surgery, respectively. No significant difference was found in the overall survival rate between the ESD and surgery groups (OR, 2.29; 95% CI, 0.98–5.36; p=0.06). However, ESD was associated with a higher recurrence rate and a lower complete resection rate. The adverse event rate was similar between the two groups.

Conclusions

ESD with meticulous surveillance esophagogastroduodenoscopy may be as effective and safe as surgery in patients with undifferentiated-type early gastric cancer. Further large-scale, randomized, controlled studies from additional regions are required to confirm these findings.

Controversies in EUS: Do we need miniprobes?

This is the fifth in a series of papers entitled "Controversies in EUS." In the current paper, we deal with high-resolution catheter probes, otherwise known as EUS miniprobes (EUS-MPs). The application of miniprobes for early carcinomas in the entire intestinal tract, for subepithelial lesions, and for findings in the bile duct and pancreatic duct as well as endobronchial use is critically discussed. Submucous lesions, especially in the colon, but also early carcinomas in special cases are considered the most important indications. The argument is illustrated by numerous examples.

Endoscopic Resection of Undifferentiated-type Early Gastric Cancer

Early detection of gastric cancer is crucial because the survival rate can be improved through curative treatment. Although surgery and gastrectomy with lymph node dissection remain as the gold standard for curative treatment, early gastric cancer (EGC) with negligible risk of lymph node metastasis can be treated with endoscopic resection (ER), such as endoscopic submucosal dissection. Among gastric cancers, undifferentiated-type cancer is distinguished from differentiated-type cancer in various aspects in terms of clinical features and pathophysiology. The undifferentiated-type cancer is also known to be associated with an aggressive behavior and a poor prognosis. Therefore, the indication of ER for undifferentiated EGC is limited compared with differentiated-type. Recent studies have reported that ER for undifferentiated EGC is safe and shows favorable short- and long-term outcomes. However, it is necessary to understand the details of the research results and to selectively accept them. In this review, we aimed to evaluate the current practice guidelines and the short-term and long-term outcomes of ER for undifferentiated type EGC.

Large population-based study using the SEER database: is endoscopic resection appropriate for early gastric cancer patients in the United States?

AIM

To investigate whether endoscopic treatment is applicable to American patients and explores the predictors of lymph node metastasis (LNM) in early gastric cancer (EGC).

METHODS

Patients with EGC confined to either mucosa (T1a, n = 1799) and submucosa (T1b, n = 1689) were identified from the Surveillance, Epidemiology, and End Result database. Multivariate logistic regression, Kaplan-Meier method, and univariate/multivariate Cox regression were used to assess the correlation between invasion depth and LNM or prognosis. A nomogram for predicting LNM was constructed and internally validated.

RESULTS

EGC limited to T1a exhibited a 2.4% incidence of LNM, which increased to 11.1% when the depth invaded T1b.LNM was present at 1.4%, 5.2%, and 5.0% for sizes ≤2, 2-5, and >5cm of low-grade T1a EGC, respectively, (p = .019) and at 4.8%, 12.4%, and 28.6% of T1b EGC, respectively (p  < .001).The multivariate logistic model revealed that older age, T1b invasion, larger tumor size, and high-grade lesions were associated with a higher risk of LNM. Moreover, the T1a EGC patients had better cancer-specific survival (OS) and overall survival(CSS) compared with the T1b EGC patients (5-year OS: 77.2% versus 67.4%, p < .001; 5-year CSS: 90.6% versus 81.4%, p < .001). The discrimination of the prediction model was 0.745.

CONCLUSIONS

Endoscopic treatment may only be suitable for patients in the US population who have low-grade T1a lesions of less than 2 cm in size. Patients with T1a lesions of greater than 2 cm in size, lesions with high-grade, and all T1b lesions may benefit from radical surgical resection with lymphadenectomy.

Does Helicobacter pylori Eradication Reduce the Incidence of Metachronous Gastric Cancer After Curative Endoscopic Resection of Early Gastric Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Whether Helicobacter pylori eradication could reduce the risk of metachronous gastric cancer remain controversial. In the present study, we performed a systematic review and meta-analysis to evaluate the preventive effect of H. pylori eradication on the occurrence of metachronous gastric cancer after curative endoscopic resection of early gastric cancer.

METHODS

The related studies were identified by searching PubMed and Embase databases. According to the H. pylori infection status and subsequent treatment, all patients were classified into H. pylori negative group, H. pylori eradication group and noneradication group. The relevant data were extracted and pooled effect size was assessed using a fixed effect model or a random effect model.

RESULTS

A total of 11 retrospective cohort studies and 3 randomized controlled trials were included in this meta-analysis. The results based on the cohort studies indicated that the risk of metachronous gastric cancer was significantly lower in H. pylori eradication group than in noneradication group (hazard ratios: 0.65, 95% confidence interval: 0.50-0.86, P=0.002; I=0%). The pooled result of 2 randomized controlled trials demonstrated that the patients receiving anti-H. pylori treatment had a lower risk of metachronous gastric cancer than those who did not receive H. pylori eradication treatment (hazard ratios: 0.43, 95% confidence interval: 0.26-0.70, P=0.001; I=0%). In addition, the occurrence of metachronous gastric cancer in H. pylori eradication group was not significantly different from that in H. pylori negative group.

CONCLUSIONS

Successful H. pylori eradication may be useful for the prevention of metachronous gastric cancer after curative endoscopic resection of early gastric cancer. Thus, anti-H. pylori treatment should be considered for those patients with H. pylori infection after curative endoscopic resection.

Indocyanine green fluorescence lymphography during gastrectomy after initial endoscopic submucosal dissection for early gastric cancer

BACKGROUND

Indocyanine green (ICG) fluorescence lymphography can be used to visualize the lymphatic drainage of gastric cancer. Few studies have been performed to identify lymphatic drainage patterns after endoscopic submucosal dissection (ESD). ESD results in changes to lymphatics owing to fibrosis of the submucosal layer. This study aimed to evaluate the efficacy of ICG fluorescence lymphography for visualization of lymphatic drainage after ESD, and to assess its clinical application in additional gastrectomy after ESD for early gastric cancer.

METHODS

All patients who underwent gastrectomy after ESD between 2014 and 2017 in a single centre were reviewed. ICG was injected endoscopically into the submucosal layer around the ESD scar the day before surgery. At the time of surgery, lymph nodes (LNs) were visualized and lymphadenectomy was performed with near-infrared imaging. Ex vivo, all LNs were examined for the presence of fluorescence. Number of LNs resected and number of tumour-positive LNs were compared between patients who underwent near-infrared imaging and those who had conventional lymphadenectomy without intraoperative imaging.

RESULTS

Some 290 patients underwent gastrectomy after ESD, 98 with fluorescence lymphography-guided lymphadenectomy and 192 with conventional lymphadenectomy. Fluorescence lymphography visualized lymphatic drainage in all patients, without complications related to ICG injection or near-infrared imaging. Fluorescence lymphography visualized all stations containing metastatic LNs. The sensitivity for detecting LN metastasis in fluorescent stations was 100 per cent (9 of 9 stations), and the negative predictive value was 100 per cent (209 of 209). One patient with LN metastasis had one non-fluorescent metastatic LN within a fluorescent station.

CONCLUSION

Fluorescence lymphography successfully visualized all draining LNs after ESD, with high sensitivity and negative predictive value for detecting LN metastasis. Fluorescence lymphography-guided lymphadenectomy could be an alternative to systematic lymphadenectomy during additional surgery after ESD.

Negative Impact of Endoscopic Submucosal Dissection on Short-Term Surgical Outcomes of Subsequent Laparoscopic Distal Gastrectomy for Gastric Cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) for gastric cancer produces an artificial ulcer, and negative effects on the surgical outcomes of additional gastrectomy after ESD are anticipated. The aim of this study is to analyze the effect of ESD on subsequent laparoscopic radical gastrectomy procedures and to compare the surgical results of post-ESD patients with the control group using propensity score (PS) methods.

PATIENTS AND METHODS

From 2013 to 2018, 1446 patients underwent totally laparoscopic distal gastrectomy in our center. Among these patients, the clinicopathological factors and short-term surgical outcomes of 107 patients who underwent ESD before surgery (the ESD group) were evaluated. A 1:4 PS matching and inverse probability weighting method was utilized to compare the short-term surgical outcomes of the ESD group with those of a matched control group.

RESULTS

A longer operation time was required for the patients who underwent gastrectomy earlier than 24 days after ESD than for the patients who did not. Patients whose ulcer size, due to previous ESD, exceeded 4.6 cm required longer operation times and exhibited more intraoperative blood loss than patients whose ulcer size was small. In the PS matching analysis, patients who underwent distal gastrectomy within 24 days after ESD showed more frequent postoperative morbidity than non-ESD patients.

CONCLUSIONS

ESD after laparoscopic distal gastrectomy is largely safe in terms of short-term surgical outcomes, but a short interval between the two procedures and a large ESD scar can make subsequent operation difficult.

Gastric endoscopic submucosal dissection: a systematic review and meta-analysis on risk factors for poor short-term outcomes

OBJECTIVE

Endoscopic submucosal dissection (ESD) is now established as the first option to manage early gastric neoplasms, but its efficacy may vary according to diverse factors. We aimed to systematically identify risk factors for poor short-term outcomes of gastric ESD with the purpose to improve patients' selection and management.

METHODS

Three online databases (MEDLINE, ISI Web of Knowledge and Scopus) were searched (last search on June 2018) for poor outcomes of gastric ESD (deep submucosal invasion, piecemeal/incomplete resection, noncurative resection and local recurrence).

RESULTS

One hundred five studies were included referring to 52.126 ESDs. Undifferentiated histology and upper location (vs lower) were associated with submucosal invasion [odds ratio (OR) = 2.42 [95% confidence interval (CI), 1.62-3.61] and OR = 3.20 (1.04-9.86), respectively] and deep submucosal invasion [OR = 2.98 (2.02-4.39) and OR = 2.35 (1.45-3.81), respectively]. Lesion size greater than 30 mm and ulceration were associated with piecemeal resection [OR = 2.78 (1.17-6.60) and OR = 2.76 (1.23, 6.20), respectively]. Lesion size greater than 30 mm, ulceration, upper location and fibrosis were risk factors for incomplete resection [OR = 3.83 (2.68-5.49), OR = 4.06 (1.62-10.16), OR = 3.71 (2.49-5.54) and OR = 4.46 (1.66-11.96), respectively]. A noncurative resection was more often observed for lesions located in the upper third of the stomach [OR = 1.49 (1.24-1.79)], depressed morphology [OR = 1.49 (1.04-2.12)] and those outside standard criteria [OR = 3.56 (2.31-5.48)]. Older age was significantly linked with local recurrence rates [OR = 3.08 (1.13-5.02)].

CONCLUSION

Several risk factors influence poor efficacy short-term outcomes of gastric ESD that may be used to inform both patients and health providers about the expected efficacy.

Oncologic Safety of Endoscopic Resection Based on Lymph Node Metastasis in Ulcerative Early Gastric Cancer

Background: There is little evidence regarding appropriate therapeutic modalities for ulcerative-type early gastric cancer (EGC) because the risks and implications of lymph node metastasis are unclear. The indication for endoscopic submucosal dissection (ESD) was investigated for ulcerative-type EGC. Methods: We retrospectively analyzed 192 patients with differentiated ulcerative-type EGC who underwent radical gastrectomy with D2 lymph node dissection. Lymph node metastasis (LNM) risk factors were evaluated using multivariate logistic regression. Results: The LNM rate was 15.1% overall, 0% for mucosa-confined lesions, and 28.2% for submucosa-infiltrating lesions. On multivariate analysis, only lymphovascular invasion (P < .001) was significantly associated with LNM. Among patients with minute submucosal invasion and no lymphovascular invasion, LNM was only observed for tumor sizes ≥2.1 cm. Conclusions: Because LNM risks are negligible, curative ESD could be considered in patients with ulcerative EGC that is confined to the mucosa and histologically differentiated, irrespective of tumor size. In addition, ESD can be attempted for ulcerative EGC with minute submucosal invasion and tumor size <2.1 cm.

Risk Factors Associated with Lymph Node Metastasis for Early Gastric Cancer Patients Who Underwent Non-curative Endoscopic Resection: a Systematic Review and Meta-analysis

BACKGROUND

Recently, increased evidence indicated that additional surgery should be performed in highly selected patients with non-curative endoscopic resection. In this study, we performed a systematic review and meta-analysis to evaluate the risk factors associated with lymph node metastasis for the patients with non-curative endoscopic resection of early gastric cancer.

METHODS

The related studies were identified by searching PubMed and Embase databases. According to the status of lymph node metastasis, all patients were classified into node-negative group and node-positive group. The relevant clinicopathologic factors were extracted, and the pooled odds ratio (OR) and 95% confidence interval (CIs) were assessed using a fixed effects model or random effects model.

RESULTS

A total of nine relevant studies involving 1720 early gastric cancer patients who underwent additional surgery following the non-curative endoscopic resection were included in this meta-analysis. The results indicated that deeper submucosal invasion (SM2) (OR 3.44, 95% CI 1.94-6.10, P < 0.001; I² = 0%), positive vertical margin (OR 2.35, 95% CI 1.57-3.53, P < 0.001; I² = 0%), lymphatic invasion (OR 11.06, 95% CI 5.47-22.36, P < 0.001; I² = 0%), and vascular invasion (OR 2.79, 95% CI 1.68-4.64, P < 0.001; I² = 0%) were significantly associated with lymph node metastasis for these patients. However, horizontal margin, tumor size, differentiation type, and ulceration were not identified as risk factors associated with lymph node metastasis.

CONCLUSION

Lymphatic invasion, vascular invasion, deeper submucosal invasion (SM2), and positive vertical margin should be strongly considered in selecting the candidates for additional surgery treatment.

Pitfalls in the Interpretation of Publications about Endoscopic Submucosal Dissection of Early Gastric Cancer with Undifferentiated-Type Histology

Endoscopic submucosal dissection (ESD) is a standard treatment for patients with gastrointestinal neoplasms with a negligible risk of lymph node metastasis. ESD enables en bloc resection of gastrointestinal neoplasms and organ preservation, thereby, avoiding surgical treatment. Although small (<2 cm) intramucosal early gastric cancer with undifferentiated-type histology (EGC-UH) without ulceration is included in the expanded criteria for ESD, controversies remain due to different biology and characteristics compared to EGC with differentiated-type histology. The authors previously presented studies about the technical feasibility of ESD for these lesions using a meta-analysis and retrospective multicenter analysis. However, many pitfalls were identified in the interpretation of studies analyzing histologic discrepancy, mixed-type histology, criteria-based analysis of therapeutic outcomes, interpretation of curative resection, and long-term clinical outcomes. In this review, the authors discuss pitfalls in the interpretation of publications on ESD for EGC-UH.

Short-term outcomes of multicenter prospective cohort study of gastric endoscopic resection: 'Real-world evidence' in Japan

OBJECTIVES

A Japanese multicenter prospective cohort study examining endoscopic resection (ER) for early gastric cancer (EGC) has been conducted using a Web registry developed to determine the short-term and long-term outcomes based on absolute and expanded indications. We hereby present the short-term outcomes of this study.

METHODS

All consecutive patients with EGC or suspected EGC undergoing ER at 41 participating institutions between July 2010 and June 2012 were enrolled and prospectively registered into the Web registry. The baseline characteristics were entered before ER, and the short-term outcomes were collected at 6 months following ER.

RESULTS

Nine thousand six hundred and sixteen patients with 10 821 lesions underwent ER (endoscopic submucosal dissection [ESD]: 99.4%). The median procedure time was 76 min, and R0 resections were achieved for 91.6% of the lesions. Postoperative bleeding and intraoperative perforation occurred in 4.4% and 2.3% of the patients, respectively. Significant independent factors correlated with a longer procedure time (120 min or longer) were as follows: tumor size >20 mm, upper-third location, middle-third location, local recurrent lesion, ulcer findings, gastric tube, male gender, and submucosa. Histopathologically, 10 031 lesions were identified as common-type gastric cancers. The median tumor size was 15 mm. Noncurative resections were diagnosed for 18.3% of the lesions. Additional surgery was performed for 48.6% (824 lesions) of the 1695 noncurative ER lesions with a possible risk of lymph node (LN) metastasis. Among them, 64 (7.8%) exhibited LN metastasis.

CONCLUSIONS

This multicenter prospective study showed favorable short-term outcomes for gastric ESD.

Role of probe-based confocal laser endomicroscopy-targeted biopsy in the molecular and histopathological study of gastric cancer

BACKGROUND AND AIM

A high yield of biopsy is mandatory to perform molecular genetic research with endoscopically obtained gastric cancer tissues. We evaluated whether probe-based confocal laser endomicroscopy (pCLE) can increase the yield of endoscopic biopsy for gastric cancer compared with white light endoscopy (WLE).

METHODS

All lesions in the pCLE and WLE groups were initially evaluated through WLE. In the pCLE group, lesions were further examined through pCLE. In the pilot study, five and three biopsy specimens were obtained for histopathological examination and tumor marker analysis, respectively. In the confirmatory study, six biopsy specimens for histopathological evaluation were obtained.

RESULTS

A total of 30 gastric cancers and 61 undifferentiated-type gastric cancers were analyzed in the pilot and confirmatory studies, respectively. The proportion of cancer cells in biopsy samples of poorly differentiated adenocarcinoma or signet ring cell carcinoma was higher in the pCLE group than in the WLE group in both the pilot and confirmatory studies (pilot: median proportion, 65% vs 30%, P = 0.010; confirmatory: mean ± standard deviation, 49.5 ± 29.3 vs 29.3 ± 13.7, P = 0.002). The expression ratio of tumor markers including carcinoembryonic antigen, GW112, HOX transcript antisense RNA, and H19 tended to be higher in the pCLE group than in the WLE group.

CONCLUSION

Probe-based confocal laser endomicroscopy-targeted biopsy provided superior results in terms of the proportion of cancer cells in biopsy samples compared with WLE-targeted biopsy in gastric cancer with undifferentiated histology.

Role of mucoprotective agents in endoscopic submucosal dissection-derived ulcers: A systematic review

BACKGROUND

Currently, it is still unclear whether adding a mucoprotective agent to a proton pump inhibitor (PPI) results in better outcomes compared with using a PPI alone in patients with post-gastric endoscopic submucosal dissection (ESD) ulcers. This study aimed to examine the efficacy of PPI alone versus combination treatment in healing of post-gastric ESD ulcers, as well as on delayed bleeding and amount of blood transfused.

METHODS

A systematic search of MEDLINE, EMBASE, Cochrane, and ISI Web of knowledge databases, up until May 2017, for randomized trials comparing PPI alone versus PPI plus a mucoprotective drug in achieving ulcer healing in patients undergoing gastric ESD was performed. The primary outcome is scarring stage on endoscopic assessment at 4 or 8 weeks after gastric ESD.

RESULTS

From an initial 3071 citations, eight articles (n = 953 lesions from 934 patients) were analyzed. Patients receiving combination treatment achieved a scarring stage significantly more often than those on a PPIs alone at 4 or 8 weeks after ESD, (risk ratio = 1.36, 95% CI; 1.06-1.75). No study reported amount of blood transfused. There were no significant between treatment-group differences in terms of delayed bleeding (risk ratio = 0.58, 95% CI; 0.17-1.99). Neither location of ulcer nor Helicobacter pylori infection was related to ulcer scarring stage.

CONCLUSION

The limited evidences suggested combination treatment may be more effective in accelerating the process of ulcer healing in patients undergoing gastric ESD than the use of PPI alone, but does not appear to alter delayed bleeding risk.

Efficacy of second-look endoscopy in preventing delayed bleeding after endoscopic submucosal dissection of early gastric cancer

The present study aimed to evaluate whether second-look endoscopy (SLE) is able to prevent delayed bleeding after endoscopic submucosal dissection (ESD) of gastric carcinoma and to identify which types of lesion require SLE. ESD of gastric cancer at the early stage was performed on 210 patients between October 2014 and September 2016. Mucosal damage-associated bleeding within 24 h after ESD was considered as delayed bleeding. The association of the characteristics of patients and lesions, as well as surgical factors, with the incidence of bleeding as a measure of outcome was analyzed. A total of 110 patients with melena and/or hematemesis underwent SLE on the second day following gastric ESD. Within the entire cohort (n=210), late delayed bleeding (LDB) was defined as hematemesis or melena occurring following second-look endoscopy. Early delayed bleeding (EDB) was defined as hematemesis or melena occurring from the end of ESD to second-look endoscopy, or as active or possible bleeding at the time of the second-look endoscopy was reported in 17 (8.1%) and 20 patients(9.5%), respectively. The median interval between late delayed bleeding and ESD was one day (range, 1–10 days). The incidence of late delayed bleeding was significantly decreased in the SLE group compared with that in the non-SLE group (4.5 vs. 12%, P=0.028). Multivariate analyses revealed that ulcer, flat gross type, lesion diameter (>2 cm), the resected tumor size of >40 mm and Helicobacter pylori infection were independently associated with late delayed bleeding after ESD, while flat gross type, ulcer, the resected tumor size of >40 mm and artificial ulcer diameter >3 cm were independently associated with early delayed bleeding. Thus, the data of the present study indicates that second-look endoscopy following gastric ESD may be useful in preventing post-ESD delayed bleeding and should be performed on the second day.

Outcomes of Endoscopic Submucosal Dissection for Early Gastric Cancer with Undifferentiated-Type Histology: A Clinical Simulation Using a Non-Selected Surgical Cohort

Background/Aims

Outcomes of endoscopic submucosal dissection (ESD) for undifferentiated-type early gastric cancer (EGC) need to be further evaluated. We aimed to simulate the outcomes of ESD for undifferentiated-type EGC from a surgical database.

Methods

Among 802 patients who underwent gastrectomy with endoscopic biopsy for poorly differentiated adenocarcinoma (PD-type) or signet ring cell carcinoma (SRC-type), ESD candidates meeting the expanded indication (n=280) were selected by reviewing the endoscopic images. According to the surgical pathologic results, the outcomes of the ESD simulation were evaluated.

Results

Among the candidates, 104 (37.1%) were PD-type and 176 (62.9%) were SRC-type. The curative resection (CR) rate was 42.1%. Among the patients with CR, three patients (2.5%) showed lymph node metastasis (LNM). Three EGCs with CR and LNM were mucosal cancers ≥1.0 cm in size. The CR rate was higher in the SRC-type than in the PD-type (48.3% vs 31.7%, respectively, p=0.007). In the SRC-type, the CR rate was increased, with a smaller size criterion for the ESD indication, but was similar between the 1.0 cm and 0.6 cm criteria (63.3% and 63.6%, respectively), whereas the CR rate was below 50% in all of the different tumor size criteria (2.0 to 0.6 cm) in the PD-type.

Conclusions

In undifferentiated-type EGC, ESD should be considered in selected patients with tumor sizes ＜1 cm and SRC histology.

Comparative efficacy of various anti-ulcer medications after gastric endoscopic submucosal dissection: a systematic review and network meta-analysis

BACKGROUND

The comparative efficacy of various anti-ulcer medications after gastric endoscopic submucosal dissection (ESD) has not been fully evaluated. Recently, vonoprazan, a novel potassium-competitive acid blocker, has also been used in ulcer treatment after ESD.

METHODS

We searched for all relevant randomized controlled trials examining the efficacy of anti-ulcer medications after gastric ESD, published through October 2017. Healing of iatrogenic ulcers was investigated at 4-8 weeks after ESD. A network meta-analysis was performed to calculate the network estimates.

RESULTS

Twenty-one studies with 2005 patients were included. Concerning the comparative efficacy for ulcer healing at 4 weeks after ESD, no network inconsistency was identified (Cochran's Q-test, df = 10, P = 0.13; I² = 34%). A combination therapy of proton-pump inhibitor (PPI) and muco-protective agent was superior to PPI alone [risk ratio (RR) (95% confidence interval, CI) 1.69 (1.20-2.39)]. The combination therapy of PPI and muco-protective agents tended to be superior to vonoprazan [RR (95% CI) 1.98 (0.99-3.94)]. There was no difference of ulcer healing effect between PPI and vonoprazan [RR (95% CI) PPI vs. vonoprazan, 1.17 (0.64-2.12)]. Concerning the ulcer healing rate at 8 weeks after ESD, however, vonoprazan was superior to PPI [RR (95% CI) 1.27 (1.03-1.56)]. Additionally, vonoprazan tended to be superior to the combination therapy of PPI and muco-protective agent [RR (95% CI) 1.20 (0.96-1.51)].

CONCLUSIONS

A combination therapy of PPI and muco-protective agent was superior to PPI alone for ulcer healing at 4 weeks after ESD. In the ulcer healing effect at 8 weeks after ESD, vonoprazan was superior to PPI.

Comparing outcomes for endoscopic submucosal dissection between Eastern and Western countries: A systematic review and meta-analysis

AIM

To compare endoscopic submucosal dissection (ESD) outcomes between Eastern and Western countries.

METHODS

A systematic review and meta-analysis was performed using PubMed, MEDLINE, Web of Science, CINAHL and EBM reviews to identify studies published between 1990 and February 2016. The primary outcome was the efficacy of ESD based on information about either curative resection, en bloc or R0 resection rates. Secondary outcomes were complication rates, local recurrence rates and procedure times.

RESULTS

Overall, 238 publications including 84318 patients and 89512 gastrointestinal lesions resected using ESD were identified. 90% of the identified studies reporting ESD on 87296 lesions were conducted in Eastern countries and 10% of the identified studies reporting ESD outcomes in 2216 lesions were from Western countries. Meta-analyses showed higher pooled percentage of curative, en bloc, and R0 resection in the Eastern studies; 82% (CI: 81%-84%), 95% (CI: 94%-96%) and 89% (CI: 88%-91%) compared to Western studies; 71% (CI: 61%-81%), 85% (CI: 81%-89%) and 74% (CI: 67%-81%) respectively. The percentage of perforation requiring surgery was significantly greater in the Western countries (0.53%; CI: 0.10-1.16) compared to Eastern countries (0.01%; CI: 0%-0.05%). ESD procedure times were longer in Western countries (110 min vs 77 min).

CONCLUSION

Eastern countries show better ESD outcomes compared to Western countries. Availability of local ESD expertise and regional outcomes should be considered for decision making to treat gastrointestinal lesions with ESD.

Long-term outcomes of endoscopic submucosal dissection versus surgery in early gastric cancer meeting expanded indication including undifferentiated-type tumors: a criteria-based analysis

BACKGROUND

Endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) meeting the expanded indication is considered investigational. We aimed to compare long-term outcomes of ESD and surgery for EGC in the expanded indication based on each criterion.

METHODS

This study included 1823 consecutive EGC patients meeting expanded indication conditions and treated at a tertiary referral center: 916 and 907 patients underwent surgery or ESD, respectively. The expanded indication included four discrete criteria: (I) intramucosal differentiated tumor, without ulcers, size >2 cm; (II) intramucosal differentiated tumor, with ulcers, size ≤3 cm; (III) intramucosal undifferentiated tumor, without ulcers, size ≤2 cm; and (IV) submucosal invasion <500 μm (sm1), differentiated tumor, size ≤3 cm. We selected 522 patients in each group by propensity score matching and retrospectively evaluated each group. The primary outcome was overall survival (OS); the secondary outcomes were disease-specific survival (DSS), recurrence-free survival (RFS), and treatment-related complications.

RESULTS

In all patients and subgroups meeting each criterion, OS and DSS were not significantly different between groups (OS and DSS, all patients: p = 0.354 and p = 0.930; criteria I: p = 0.558 and p = 0.688; criterion II: p = 1.000 and p = 1.000; criterion III: p = 0.750 and p = 0.799; and criterion IV: p = 0.599 and p = 0.871). RFS, in all patients and criterion I, was significantly shorter in the ESD group than in the surgery group (p < 0.001 and p < 0.003, respectively). The surgery group showed higher rates of late and severe treatment-related complications than the ESD group.

CONCLUSIONS

ESD may be an alternative treatment option to surgery for EGCs meeting expanded indications, including undifferentiated-type tumors.

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.

A non-randomized confirmatory trial of an expanded indication for endoscopic submucosal dissection for intestinal-type gastric cancer (cT1a): the Japan Clinical Oncology Group study (JCOG0607)

BACKGROUND

Endoscopic resection has been limited to intestinal-type gastric cancer (cT1a) with a low risk of lymph node metastasis (T1a ≤2 cm, without ulcers). This single-arm confirmatory trial evaluated the efficacy and safety of endoscopic submucosal dissection (ESD) for >2 cm ulcer-negative and ≤3 cm ulcer-positive intestinal-type gastric cancer (cT1a).

METHODS

The eligibility criteria included endoscopically diagnosed cT1a, a single primary intestinal-type gastric adenocarcinoma, an ulcer-negative lesion of any size or a ≤3 cm ulcer-positive lesion, cN0M0, and no prior treatment. If ESD resulted in noncurative resection, surgical resection was added. The primary endpoint was the 5-year overall survival (OS) (planned sample size was 470, with a one-sided alpha level of 2.5%). The threshold 5-year OS was 86.1%.

RESULTS

We enrolled 470 early gastric cancer patients [median tumor size, 25 (5-130) mm] from 29 institutions between June 2007 and October 2010. These patients had 152 ulcer-negative lesions (>2 and ≤3 cm), 111 ulcer-negative lesions (>3 cm), and 207 ulcer-positive lesions (≤3 cm). The success rate for en block resection was 99.1% (466/470). Additional gastrectomy was conducted in 131 patients (28%) who did not fulfill the curative resection criteria. The 5-year OS of all patients was 97.0% (95% confidence interval, 95.0-98.2%), which was higher than the threshold 5-year OS (86.1%). The 317 patients who satisfied the curative resection criteria had no recurrence. There were no ESD-related grade 4 adverse events.

CONCLUSION

ESD for early gastric cancers that met the expanded criteria for intestinal-type gastric cancer (cT1a) was acceptable and should be the standard treatment instead of gastrectomy.

Endoscopic resection versus radical gastrectomy for early gastric cancer in Asia: A meta-analysis

BACKGROUND

To compare the efficacy and safety of endoscopic resection (ER) and radical gastrectomy (RG) for early gastric cancer (EGC) in Asia.

MATERIALS AND METHODS

We systematically searched relevant articles published before September 1, 2017. We evaluated the quality of the included non-randomized studies using the Newcastle-Ottawa Scale (NOS). Meta-analysis was carried out using RevMan 5.3 software. The odds ratio (OR) with 95% confidence intervals (CI) were used for the dichotomous data.

RESULTS

Fifteen retrospective studies were included in this analysis (3737 patients in the ER group and 4246 patients in RG group). No significant differences in the three-year survival rate (OR, 0.87; 95%CI, 0.50-1.53) and five-year survival rate (OR, 0.81; 95%CI, 0.58-1.13) between the ER and RG groups were observed. Although patients undergoing ER had a higher risk of recurrence (OR, 6.07; 95%CI 4.17-8.84) and the occurrence of metachronous cancer (OR, 8.35; 95%CI, 5.48-12.75), recurrent or metachronous gastric cancers following ER were successfully detected and removed using the endoscopic technique. Higher recurrence in the ER group may be associated with its lower en bloc resection rate (OR, 0.05; 95%CI, 0.02-0.14) and complete resection rate (OR, 0.03; 95%CI, 0.01-0.08). Importantly, although the three-year survival and five-year survival were similar in the two groups, the complication rate in the ER group was significantly lower than that in the RG group.

CONCLUSION

ER is a good choice for patients with small EGC lesions (≤2 cm) without lymph node metastasis, especially in elderly patients with various medical comorbidities and in patients who cannot tolerate abdominal surgery or who meet the criteria but decline surgery. In contrast, RG is recommended when the diameter of the tumor is large (>2 cm) and preoperative examination suggests the possible presence of lymph node metastasis.

Endoscopic submucosal dissection for esophagogastric junction tumors: a single-center experience

BACKGROUND

Surgical resection for esophagogastric junction (EGJ) tumors is more aggressive and worsens the quality of life of the patients and leads to poor prognosis even after surgery compared with tumors in other sites of the stomach. Endoscopic submucosal dissection (ESD) is a widely accepted treatment modality for premalignant lesions and early cancers in the stomach. However, EGJ tumor is one of the most technically difficult lesions to resect by ESD. Therefore, this study aimed to evaluate the therapeutic outcomes of ESD for EGJ epithelial neoplasms and to assess the predictive factors for incomplete resection.

METHODS

We conducted a retrospective observational study of 48 patients who underwent ESD for adenomas and early cancers of the EGJ between March 2006 and November 2015 at the Pusan National University Hospital. Therapeutic outcomes of ESD and procedure-related adverse events were analyzed.

RESULTS

En bloc resection, complete resection, and curative resection rates were 96, 77, and 71%, respectively. Multivariate analyses showed that the presence of ulceration was an independent predictive factor for incomplete resection (odds ratio 21.3, 95% confidence interval 1.51-298.49; p = 0.023). The procedure-related bleeding, perforation, and stenosis rates were 8, 4, and 0%, respectively; none of the adverse events required surgical intervention. During a median follow-up period of 25 months (range 6-72 months), local recurrence occurred in four patients with incomplete resection.

CONCLUSION

ESD is an effective, safe, and feasible treatment for EGJ epithelial neoplasms. However, the complete resection rate decreases for tumors with ulceration.

Antral or Pyloric Deformity Is a Risk Factor for the Development of Postendoscopic Submucosal Dissection Pyloric Strictures

BACKGROUND/AIMS

Surgeons must be aware of risk factors for strictures before performing endoscopic submucosal dissection (ESD), to enable early interventions to prevent severe strictures.

METHODS

This study was a single-center retrospective study. We reviewed the clinical data of patients who has undergone gastric ESD from January 2007 to December 2012.

RESULTS

Among the 3,819 patients who had undergone gastric ESD, 11 patients (7.2%) developed pyloric strictures and received successful endoscopic balloon dilation. Significant differences were noted between the patients without and with post-ESD strictures for pretreatment of antral or pyloric deformities (46.4% vs 81.8%), the proportion of extension to the lumen circumference (>3/4, 9.4% vs 54.5%), the longitudinal extent of mucosal defects (27.9±10.1 mm vs 51.5±10.8 mm), and post-ESD bleeding (2.9% vs 27.3%). Multivariate analysis revealed that pretreatment antral or pyloric deformities (odds ratio [OR], 30.53; 95% confidence interval [CI], 1.476 to 631.565; p=0.027), larger longitudinal extent of mucosal defects (OR, 1.20; 95% CI, 1.074 to 1.340; p=0.001), and circumferential extension of ≥3/4 (OR, 13.69; 95% CI, 1.583 to 118.387; p=0.017) were independent risk factors for post-ESD stricture.

CONCLUSIONS

Antral or pyloric deformities, sub-circumferential resection over more than 75% of the circumference and greater longitudinal extent of mucosal defects are independent risk factors for post-ESD stricture.

Endoscopic submucosal dissection of gastric superficial neoplastic lesions: a single Western center experience

Background

Endoscopic submucosal dissection (ESD) allows "en bloc" resection of superficial gastric lesions.

Objective

The aim of this study is to report "en bloc" resection rate, procedure results, post resection features, analysis of complications, and relapses at mid-long term follow-up on an Italian center case series of patients with superficial gastric neoplastic lesions treated with ESD.

Methods

This is a retrospective evaluation of a prospectively collected series of patients diagnosed with gastric superficial lesions who underwent ESD between November 2007 and May 2015. The analysis included demographic, clinical, endoscopic, and histological data. In detail, the following features were analyzed: (1) "en bloc" resection rate; (2) R0, R1, and RX rate; (3) complication rate; and (4) neoplastic recurrence during follow-up. A comparison was performed between lesions treated according to standard and to extended criteria.

Results

In the analysis, therefore, 70 superficial lesions and 70 endoscopic procedures were considered.Overall, 53 (76%) procedures were performed according to the extended-ESD criteria. The remaining 17 (24%) cases were performed according to standard criteria. In 68/70 (97%) procedures "en bloc" resection was successful. Forty-four (65.6%) patients had a R0 resection, while 15 (22%) patients had a R1 and the remaining 8 (12.4%) patients were RX. Two patients (2.8%) experienced a major complication. Overall, 7 patients (10.4%) required surgery: in two cases because of local recurrence, in one case for an intraprocedural complication not amenable to endoscopic treatment, in three patients with R1 vertical margins, and in the last patient because of an aggressive pathology (i.e. signet ring cell adenocarcinoma). The mean follow-up of patients with neoplastic lesions was 36.6 ± 13.1 months.

Conclusion

ESD for early gastric cancer is a safe and effective technique when performed by experienced Endoscopists also in Western setting. When comparing the outcomes of the ESD in patients with standard and extended indication there is no significant difference in terms of complete resection, complications and local recurrence rates. Larger Western studies are needed to clearly define the role and the outcomes of ESD in regions at low incidence for gastric neoplasia.

Comparison of clinical outcomes after endoscopic submucosal dissection and surgery in the treatment of early gastric cancer: A single-institute study

The feasibility of expanding the indications for endoscopic submucosal dissection to treat early gastric cancer based on long-term outcomes has shown conflicting results. This study aimed to investigate whether outcomes or adverse events associated with endoscopic submucosal dissection are comparable to those of surgery for early gastric cancer that including the absolute and expanded indications.Data of 159 early gastric cancers from 153 patients treated with endoscopic submucosal dissection or surgery between January 2004 and October 2014 were reviewed retrospectively. Early gastric cancers fulfilled the absolute or expanded indications with differentiated type adenocarcinoma were included.The endoscopic submucosal dissection and surgery group showed no significant difference in the incidence of residual disease (P = .48), local recurrence (P = .46), and metachronous cancer (P = .22). Kaplan-Meier analysis showed no significant difference in 2-year (97.6% versus [vs] 92.4%; P = .45) and 5-year (95.8% vs 95.6%; P = .26) overall survival rate between 2 groups. There was also no significant difference in 2-year (100% vs 94.1%; P = .98) and 5-year (100% vs 98.4%; P = .89) disease-free survival rate. Early and late adverse events also showed no significant differences.For the treatment of early gastric cancer fulfilled absolute and expanded indications, endoscopic submucosal dissection is not inferior modality regarding the clinical outcomes and safety, compared with surgery.

Comparative study between endoscopic submucosal dissection and surgery in patients with early gastric cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) is accepted as a standard treatment in patients with early gastric cancer (EGC) who have a negligible risk of lymph node metastasis. The aim of this study was to compare the short-term and long-term outcomes between ESD and surgery in patients with EGC that fulfilled the expanded indication of ESD on their final pathologic report.

METHODS

We reviewed the clinical data of patients who underwent gastric ESD and surgery between January 2007 and December 2012. Patients with pathologically confirmed EGC that fulfilled the expanded indication of ESD on their final pathologic report were analyzed.

RESULTS

Among 2023 patients, 817 (40.4%) underwent ESD and 1206 (59.6%) underwent surgery. The proportion of cases meeting the absolute indication was significantly higher in the ESD group than in the surgery group (66.0 vs. 26.2%). Lesions on the middle third, >3 cm in size, flat or depressed, and of undifferentiated histology were significantly more common in the surgery group than in the ESD group. The ESD group showed lower acute complication rates [8.1% (66 of 817) vs. 18.1% (218 of 1206), P ≤ 0.001] and procedure-related mortality [0 vs. 0.3% (4 of 1206), P = 0.153] than the surgical group. The annual incidence of recurrent gastric cancer was 2.18% in the ESD group and 0.19% in the surgery group. The 5-year overall and disease-specific survival rates were not significantly different between the ESD group and the surgery group (overall survival: 96.4 vs. 97.2%, P = 0.423; disease-specific survival: 99.6 vs. 99.2%, P = 0.203).

CONCLUSIONS

Although EGC lesions had poorer features in the surgery group than in the ESD group, ESD was comparable to surgery for EGCs that fulfilled the expanded indication of ESD, with lower rates of acute complication and comparable overall survival.

Role of second-look endoscopy and prophylactic hemostasis after gastric endoscopic submucosal dissection: A systematic review and meta-analysis

BACKGROUND

Although several studies have shown that second-look endoscopy does not affect the incidence of bleeding after gastric endoscopic submucosal dissection (ESD), the potential roles of second-look endoscopy have not been fully evaluated. This study aimed to determine the role of second-look endoscopy after ESD through a systematic review and meta-analysis.

METHODS

This study conducted a systematic literature search of MEDLINE, EMBASE, and the Cochrane Library through March 2016 using the keywords "second-look," "prophylactic hemostasis," "prophylactic haemostasis," "prevention," "prophylaxis," and "endoscopic submucosal dissection." Studies were included if they evaluated the incidence of post-ESD bleeding according to second-look endoscopy or prophylactic hemostasis during second-look endoscopy.

RESULTS

Four randomized controlled trials on post-ESD bleeding between second-look endoscopy and no second-look endoscopy and 12 non-randomized studies with a cohort design on post-ESD bleeding were included. On meta-analysis, second-look endoscopy did not affect delayed post-ESD bleeding (odds ratio [95% confidence interval] = 1.27 [0.80-2.00], I²  = 0%). During second-look endoscopy, patients who were considered as high-risk for post-ESD bleeding underwent prophylactic hemostasis. Delayed post-ESD bleeding was more common in patients who were treated with hemostasis during second-look endoscopy compared with those who were not (odds ratio [95% confidence interval] = 3.40 [1.87-6.18], I²  = 62%). In patients who underwent prophylactic hemostasis, the number needed to prolong a hospitalization period to avoid one additional post-ESD bleeding after discharge was 25.

CONCLUSION

Second-look endoscopy after ESD could not reduce the risk of delayed post-ESD bleeding. Delayed post-ESD bleeding was more common in patients who underwent prophylactic hemostasis than in those who did not.

Therapeutic outcomes of endoscopic submucosal dissection for early gastric cancer: single-center study

OBJECTIVES

Endoscopic submucosal dissection (ESD) has been widely accepted for selected patients with early gastric cancer (EGC). The aim of this study was to assess the therapeutic outcomes after ESD according to the pathological extent.

PATIENTS AND METHODS

From January 2005 to December 2014, a total of 599 patients with 611 lesions were enrolled in this study. The tumors were categorized according to pathological results on the basis of absolute criteria (AC), expanded criteria (EC), EC with undifferentiated histology [(EC-U), mucosal cancer, ulcer (-), ≤20 mm], or beyond EC (BEC). The therapeutic outcomes among the four groups were analyzed retrospectively.

RESULTS

The number of patients in the AC, EC, EC-U, and BEC groups was 447, 91, 19, and 54. The complete resection rates of EGC were 97.8, 84.6, 94.4, and 45.5% (P=0.001) and en bloc resection rates in the AC, EC, EC-U, and BEC groups were 99.1, 98.9, 100, and 98.1% (P=0.833), respectively. The 5-year disease-free survival rate in the AC, EC, EC-U, and BEC groups was 90.6, 88.7, 75.0, and 83.3% (P=0.394). In multivariate analysis, undifferentiated histology (P=0.001) and tumor size (>30 mm, P=0.017) were risk factors related to local recurrence.

CONCLUSION

The efficacy of ESD for EGCs in EC is almost equal to that in AC when complete resection was achieved. However, the indication for ESD should be decided conservatively because the complete resection rate of EGC in the EC group was significantly lower than that in the AC group. Undifferentiated histology and tumor size over 30 mm were risk factors related to local recurrence.

Endoscopic submucosal dissection versus surgical resection for early gastric cancer: a retrospective multicenter study on immediate and long-term outcome over 5 years

BACKGROUND

Endoscopic submucosal dissection (ESD) is an alternative to surgical resection for treating early gastric cancer (EGC). However, there have been limited reports on the long-term outcome of ESD compared to that of surgical resection. The aim of this study was to evaluate the immediate and long-term clinical and oncologic outcomes of ESD compared to surgical resection.

METHOD

We retrospectively reviewed data of patients in five centers who were treated with ESD or surgical resection for EGC within expanded criteria for ESD from 2006 to 2008.

RESULT

ESD group had significantly shorter procedure times, shorter fasting period, and shorter hospital stay than the surgical resection group. Immediate complications in the surgical resection group were more common compared to those in the ESD group. Five-year cancer recurrence rate of the ESD group was 12.3 % and significantly higher than 2.1 % of the surgical resection group (P = 0.001). Five-year disease-free survival rate of the surgical resection group was 97 %, which was significantly higher than 85 % of the ESD group (P = 0.001). Metachronous lesions were equally found every year during the follow-up period in the ESD group. Five-year overall survival rates were 100 % for both groups.

CONCLUSION

ESD might be an acceptable and effective treatment for EGC considering overall survival rates with fewer early complication rates and shorter duration of hospital stay compared to surgical resection. However, intensive and persistent endoscopic surveillance should be performed after ESD for early detection of metachronous lesions.

Incidence and impact of scheduled endoscopic surveillance on recurrence after curative endoscopic resection for early gastric cancer

BACKGROUND AND AIMS

The aim of this study was to identify the incidence of recurrent lesions after endoscopic submucosal dissection (ESD) and to determine whether scheduled endoscopic surveillance might control their development and treatment.

METHODS

We reviewed the clinical data of patients who underwent gastric ESD between March 2007 and April 2014.

RESULTS

A total of 1347 patients who underwent curative ESD for early gastric cancer that met the expanded indication for ESD were analyzed. Of these, recurrence at the previous ESD site occurred in 39 patients, whereas recurrence in the stomach at a site other than the ESD site occurred in 102 patients. Older age, intestinal metaplasia, flat or depressed lesions, and ESD criteria were associated with recurrence in the stomach in places other than the ESD site. The annual incidence was .84% for recurrence at the previous ESD site and 2.48% for recurrence in the stomach at other than the ESD site. In cases of local recurrence and metachronous lesions, there was a significant difference between the short- and long-surveillance interval group (≤12 months vs >12 months) in the proportions of recurrent adenocarcinoma (31.9% vs 60.9%, P = .021), additional gastrectomy (7.1% vs 46.2%, P = .033), and size (8.92 ± 4.17 mm vs 18.08 ± 10.47 mm, P = .010).

CONCLUSIONS

Scheduled endoscopy surveillance is necessary for detecting recurrent lesions. In addition, scheduled endoscopy surveillance might help to detect recurrent lesions at a stage early enough for a curative resection.

Risk Stratification According to the Total Number of Factors That Meet the Indication Criteria for Radical Lymph Node Dissection in Patients with Early Gastric Cancer at Risk for Lymph Node Metastasis

BACKGROUND

Extended indications for endoscopic resection for early gastric cancer (EGC) have been widely accepted. However, according to current guidelines, additional gastrectomy with lymph node dissection (LND) is recommended for patients proven to have potential risks of lymph node metastasis (LNM) on histopathological findings. The aim of this study was to elucidate the risk stratification of outcome and LNM according to the number of factors that meet the inclusion criteria for radical LND for possible LNM (LNM risk factors) in patients with negative endoscopic resection margin.

METHODS

We enrolled 511 EGC patients whose tumors did not meet the absolute or extended indications for endoscopic resection, and investigated the risk stratification of prognosis and LNM according to the total number of LNM risk factors.

RESULTS

Recurrence-free and overall survival rates were significantly higher in patients with fewer LNM risk factors for surgical indication (p = 0.0274 and 0.0002, respectively; log-rank test), and the total number of LNM risk factors and frequency of LNM were significantly correlated (p < 0.0001; Kruskal-Wallis test). When only one LNM risk factor was satisfied, the LNM ratio was 0.58 % (1/173, 95 % confidence interval 0.01-3.18).

CONCLUSION

The present study suggested the possibility of using further minimally invasive treatment strategies based on the total number of LNM risk factors.

Endoscopic submucosal dissection of gastric tumors: A systematic review and meta-analysis

AIM: To systematically review the medical literature in order to evaluate the safety and efficacy of gastric endoscopic submucosal dissection (ESD).

METHODS: We performed a comprehensive literature search of MEDLINE, Ovid, CINAHL, and Cochrane for studies reporting on the clinical efficacy and safety profile of gastric ESD.

RESULTS: Twenty-nine thousand five hundred and six tumors in 27155 patients (31% female) who underwent gastric ESD between 1999 and 2014 were included in this study. R0 resection rate was 90% (95%CI: 87%-92%) with significant between-study heterogeneity (P < 0.001) which was partly explained by difference in region (P = 0.02) and sample size (P = 0.04). Endoscopic en bloc and curative resection rates were 94% (95%CI: 93%-96%) and 86% (95%CI: 83%-89%) respectively. The rate of immediate and delayed perforation rates were 2.7% (95%CI: 2.1%-3.3%) and 0.39% (95%CI: 0.06%-2.4%) respectively while rates of immediate and delayed major bleeding were 2.9% (95%CI: 1.3-6.6) and 3.6% (95%CI: 3.1%-4.3%). After an average follow-up of about 30 mo post-operative, the rate of tumor recurrence was 0.02% (95%CI: 0.001-1.4) among those with R0 resection and 7.7% (95%CI: 3.6%-16%) among those without R0 resection. Overall, irrespective of the resection status, recurrence rate was 0.75% (95%CI: 0.42%-1.3%).

CONCLUSION: Our meta-analysis, the largest and most comprehensive assessment of gastric ESD till date, showed that gastric ESD is safe and effective for gastric tumors and warrants consideration as first line therapy when an expert operator is available.

Periodic Endoscopies Might Not Increase the Detection of Early Gastric Cancer in a Young Population

Background

Screening endoscopies in individuals 40 years or older in regions where gastric cancer is prevalent increase the diagnosis of gastric cancer at an early stage. However, the benefits of screening endoscopies in a young population (<40 years) have not been evaluated.

Methods

We reviewed data from patients less than 40 years old who underwent endoscopic submucosal dissection or surgery for initial-onset gastric cancer. We also administered a questionnaire to gather information concerning periodic endoscopic inspections and the period from the penultimate endoscopy to diagnosis.

Results

Of the 564 patients in this study, 101 (17.9%) patients underwent screening endoscopy within 24 months of their gastric cancer diagnosis. Lesion size was significantly smaller in the ≤24 months group than in the >24 month group (23.8 mm [standard deviation, 22.2 mm] vs. 30.5 mm [standard deviation, 23.1 mm], P = 0.008). However, the proportion of patients with early gastric cancer did not differ between the two groups (≤24 months vs. >24 months group; 67.6% vs. 65.7%, P = 0.712). On multivariable analysis, periodic endoscopies did not influence the early diagnosis of gastric cancer (with >24 months as the reference group: ≤24 months, odds ratio = 0.939, 95% confidence interval = 0.583–1.513).

Conclusion

Although periodic endoscopies aided in the detection of gastric cancer when lesions were smaller in size, they seemed not to increase the proportion of patients with early gastric cancer in young patients diagnosed with resectable gastric cancer.

Endoscopic resection versus surgery for early gastric cancer: a systematic review and meta-analysis

OBJECTIVES

Endoscopic resection (ER) is becoming an increasingly used treatment option for early gastric cancer (EGC); however, data comparing the long-term outcomes of ER and surgery are limited. Accordingly, we here aimed to perform a meta-analysis to clarify the long-term outcomes and safety of ER and surgery for EGC.

METHODS

Literature on the direct comparison of ER and surgery for EGC was retrieved from the Medline, PubMed and Scopus databases. We selected the eligible studies, extracted data, and assessed the quality scores according to the guidelines. The overall survival (OS), recurrence-free survival (RFS), and adverse event rates were investigated, and the pooled hazard ratio (HR), odds ratio (OR), and 95% confidence interval (CI) were estimated.

RESULTS

Nine retrospective studies were identified, including 973 and 1190 participants undergoing ER and surgery, respectively. There were no significant differences regarding the OS (HR: 0.995, 95% CI: 0.836-1.185; P = 0.959) and adverse event rates (OR: 0.50, 95% CI: 0.20-1.28, P = 0.148) between ER and gastrectomy. However, patients undergoing ER had significantly shorter RFS (HR: 7.226, 95% CI: 1.718-30.400, P = 0.007) than those undergoing gastrectomy.

CONCLUSIONS

Despite the limitations of this review, including the retrospective nature of all included studies, our results suggest that ER might be a feasible and safe treatment strategy compared to that of gastrectomy for EGC; however, careful endoscopic surveillance is needed for ensuring favorable outcomes. These findings should be confirmed in further large-scale, prospective, randomized, controlled trials from different countries.

Discrepancy between Clinical and Final Pathological Evaluation Findings in Early Gastric Cancer Patients Treated with Endoscopic Submucosal Dissection

PURPOSE

Early gastric cancer cases that are estimated to meet indications for treatment before endoscopic submucosal resection are often revealed to be out-of-indication after the treatment. We investigated the short-term treatment outcomes in patients with early gastric cancer according to the pretreatment clinical endoscopic submucosal resection indications.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of patients with early gastric cancer that met the pretreatment endoscopic submucosal resection indications, from 2004 to 2011. Curative resection rate and proportion of out-of-indication cases were compared according to the pre-endoscopic submucosal resection indications. Pre-endoscopic submucosal resection factors associated with out-of-indication in the final pathological examination were analyzed.

RESULTS

Of 756 cases, 660 had absolute and 96 had expanded pre-endoscopic submucosal resection indications. The curative resection rate was significantly lower in the patients with expanded indications (64.6%) than in those with absolute indications (81.7%; P<0.001). The cases with expanded indications (30.2%) were revealed to be out-of-indication more frequently than the cases with absolute indications (13.8%; P<0.001). Age of >65 years, tumor size of >2 cm, tumor location in the upper-third segment of the stomach, and undifferentiated histological type in pre-endoscopic submucosal resection evaluations were significant risk factors for out-of-indication after endoscopic submucosal resection.

CONCLUSIONS

Non-curative resection due to out-of-indication occurred in approximately one-third of the early gastric cancer cases that clinically met the expanded indications before endoscopic submucosal resection. The possibility of additional surgery should be emphasized for patients with early gastric cancers that clinically meet the expanded indications.