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

Low Incidence of Synchronous or Metachronous Tumors after Endoscopic Submucosal Dissection for Early Gastric Cancer with Undifferentiated Histology

Background

Gastric cancer with undifferentiated histology has different clinicopathologic characteristics compared to differentiated type gastric cancer. We aimed to compare the risk of synchronous or metachronous tumors after curative resection of early gastric cancer (EGC) via endoscopic submucosal dissection (ESD), according to the histologic differentiation of the primary lesion.

Methods

Clinicopathological data of patients with initial-onset EGC curatively resected via ESD between January 2007 and November 2014 in a single institution were reviewed. We analyzed the incidence of synchronous or metachronous tumors after ESD with special reference to the differentiation status of the primary lesion.

Results

Of 1,560 patients with EGC who underwent curative resection via ESD, 1,447 had differentiated type cancers, and 113 had undifferentiated type cancers. The cumulative incidence of metachronous or synchronous tumor after ESD was higher in the differentiated cancer group than in the undifferentiated cancer group (P = 0.008). Incidence of metachronous or synchronous tumor was 4.8% and 1.2% per person-year in the differentiated and undifferentiated cancer groups, respectively. The Cox proportional hazard model revealed that undifferentiated cancers were associated with a low risk of synchronous or metachronous tumors after adjusting for confounding variables (hazard ratio [95% confidence interval] = 0.287 [0.090–0.918]).

Conclusions

The rate of synchronous or metachronous tumors after curative ESD was significantly lower for undifferentiated cancers compare to differentiated cancers. These findings suggest that ESD should be actively considered as a possible treatment for undifferentiated type EGCs.

A specific role of endoscopic ultrasonography for therapeutic decision-making in patients with gastric cardia cancer

BACKGROUND

The role of endoscopic ultrasonography (EUS) in gastric cardia cancer should be further evaluated because the accuracy of EUS depends on tumor location. We aimed to identify a specific role of EUS for therapeutic decision-making in patients with gastric cardia cancer.

METHODS

Initial EUS examinations for treatment-naïve gastric cancer that were followed by endoscopic resection or surgery were included in the study. Lesions were classified as cardiac and non-cardiac cancer according to tumor location. The diagnostic performance of EUS in predicting invasion depth was compared between the two groups.

RESULTS

The overall accuracy of EUS in predicting invasion depth did not differ between the cardiac and non-cardiac cancer groups (44.4 vs. 52.3 %, P = 0.259). The underestimation rate was higher in the cardiac cancer group than in the non-cardiac cancer group (37.0 vs. 18.5 %, P = 0.001). When the depth of invasion was predicted to be deeper than the mucosa (submucosal or deeper) by EUS, the positive predictive value was 82.1 [95 % confidence interval (CI), 66.5-92.5 %] and 62.9 % (95 % CI, 60.5-66.9 %) in the cardiac and non-cardiac cancer groups, respectively (P = 0.015). In multivariable analysis, tumor location in the cardia was found to be an independent factor for the underestimation of invasion depth [odds ratio (95 % CI) = 2.242 (1.156-4.349)].

CONCLUSIONS

The underestimation rate in predicting invasion depth was significantly higher for cardiac cancers than for non-cardiac cancers. Therefore, selection of the treatment method for gastric cardia cancer via EUS should be done carefully.

Diagnostic group classifications of gastric neoplasms by endoscopic resection criteria before and after treatment: real-world experience

BACKGROUND AND STUDY AIMS

There are often discrepancies between the pretreatment evaluation of gastric neoplasms by endoscopy with biopsy and the final diagnosis of resected specimen in terms of pathology and depth of invasion. We evaluated the spectrum of discrepancies between pretreatment and posttreatment diagnosis which may deliver significant differences on clinical practice.

PATIENTS AND METHODS

A total of 2041 patients with gastric dysplasia or cancer who underwent curative endoscopic resections or surgeries in 2012 were enrolled. Patients were classified into five different diagnostic groups: low-grade dysplasia (LGD), high-grade dysplasia (HGD), absolute indication early gastric cancer (AI-EGC), beyond absolute indication early gastric cancer (BAI-EGC), and advanced gastric cancer (AGC). The choice of initial treatment and final pathologic diagnosis was analyzed.

RESULTS

The study patients belonged to the following pretreatment diagnostic groups: LGDs in 162, HGDs in 164, AI-EGCs in 396, BAI-EGCs in 824, and AGCs in 495 cases. Posttreatment diagnostic groups were LGDs in 140, HGDs in 121, AI-EGCs in 322, BAI-EGCs in 947, AGCs in 505, and no residual tumor in 6 cases. In general, 6.9 % (141/2041) of cases were downgraded and 15.9 % (324/2041) were upgraded. Thirty-four percent of pretreatment HGDs (56/164) were changed to cancers after endoscopic resection. Thirty-three percent of pretreatment AI-EGCs (131/396) were regrouped as posttreatment BAI-EGCs. The additional surgery rate in each pretreatment group was 0.6 % in LGD, 4.3 % in HGD, 15.7 % in AI-EGC, 23.6 % in BAI-EGC among the patients with initial endoscopic resection (p < 0.01).

CONCLUSIONS

Twenty-three percent of gastric neoplasms changed in their final diagnostic group after endoscopic resection or surgery. This discrepancy should be considered when the initial treatment strategy is being selected.

Predictive factors for lymph node metastasis in additional gastrectomy after endoscopic resection of cT1aN0 gastric cancer

PURPOSE

Endoscopic therapy for clinical T1aN0 (cT1aN0) gastric cancer is an excellent therapeutic strategy; however, pathological lymph node metastasis (LNM) occasionally occurs. Patients who have a potential for LNM are subject to additional gastrectomy. Our aim was to identify predictors of LNM in additional gastrectomy.

METHODS

One hundred and twelve cT1aN0 gastric cancer patients undergoing additional gastrectomy after endoscopic resection were identified between 1997 and 2013. Predictors for LNM were initially selected by a univariate analysis and applied to a multivariate analysis.

RESULTS

(1) Twelve patients (10.7 %) had LNM following additional gastrectomy. (2) Clinicopathological factors significantly associated with LNM were the depth of invasion (SM2 or deeper, designated as SM2) (p = 0.0018) and rigorous lymphatic invasion (ly2,3) (p < 0.001). (3) The univariate predictors for LNM were applied to the multivariate logistic regression model, and SM2 (p = 0.0027) and ly2,3 (p = 0.0028) remained significant predictors. (4) When classified into 2 × 2 subgroups, the predictability for LNM was as follows: SM2 plus ly2,3 (46.7 %), SM2 plus ly0,1 (10.0 %), M,SM1 plus ly2,3 (0 %), and M,SM1 plus ly0,1 (0 %).

CONCLUSIONS

In cT1aN0 gastric cancer patients, both SM2 and ly2,3 are significant predictors for LNM that may be important as references for additional gastrectomy after endoscopic resection.

Comparison of endoscopic resection and gastrectomy for the treatment of early gastric cancer: a meta-analysis

BACKGROUND

Endoscopic resection methods, including endoscopic mucosal resection and endoscopic submucosal dissection, have become standard treatment modalities for patients with early gastric cancer (EGC) and absolute indications, with en bloc resection being more frequent with the latter. Endoscopic resection, however, has been associated with higher recurrence and metachronous cancer rates than gastrectomy. This meta-analysis compared the efficacy and safety of endoscopic resection and gastrectomy for EGC.

METHODS

PubMed, EMBASE and Web of Science were electronically searched for relevant studies comparing endoscopic resection and gastrectomy for EGC from 1976 through March 2015. The primary endpoints were en bloc resection and histologically complete resection rates. The secondary endpoints were duration of hospital stay and rates of complications, recurrence, metachronous cancer and overall survival.

RESULTS

This meta-analysis enrolled 10 studies with 2070 patients: 993 patients who underwent endoscopic resection and 1077 who underwent gastrectomy. Endoscopic resection was associated with shorter hospital stay (standardized mean difference -2.02; 95 % confidence interval [CI] -2.64 to -1.39) and lower complication rate (relative risk [RR] 0.41; 95 % CI 0.22-0.76) than gastrectomy. However, endoscopic resection was associated with lower rates of en bloc resection (odds ratio [OR] 0.05; 95 % CI 0.02-0.16) and histologically complete resection (OR 0.04; 95 % CI 0.01-0.11) and higher rates of recurrence (RR 5.23; 95 % CI 2.43-11.27) and metachronous cancer (RR 5.22; 95 % CI 2.40-11.34) than gastrectomy. Overall survival rate (OR 1.18; 95 % CI 0.76-1.82) was similar.

CONCLUSIONS

Endoscopic resection is minimally invasive and as effective as surgery, suggesting that the former be considered standard treatment for EGC. It should be recommended as standard treatment for EGC with indications. Additional randomized controlled trials from more countries are required.

Endoscopic and oncologic outcomes according to indication criteria of endoscopic resection for early gastric cancer: a systematic review and meta-analysis

BACKGROUND

The criteria for endoscopic resection for early gastric cancer (EGC) have been expanded recently, and it has become acceptable to use techniques that are regarded as having equivalent technical and pathological outcomes to absolute indication (AI). However, the long-term oncological outcomes of expanded indication (EI) have yet to be clarified. This meta-analysis aimed to assess the long-term outcome of EI versus AI, to identify the endoscopic feasibility and safety according to the indication, and to provide the appropriate recommendations for each indication.

METHODS

Electronic databases including PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and KoreaMed were searched for articles published between January 2000 and October 2014. After screening, the reviewers extracted the information from 12 retrospective cohort studies. A total of 9635 EGC lesions, 4150 lesions in the EI group and 5485 lesions in the AI group, were included in this study.

RESULTS

Meta-analyses showed that the local recurrence rate [risk ratio (RR) 1.34; 95% CI 0.67-2.70] was not significantly higher in the EI group compared with the AI group, although the metachronous recurrence rate was higher in the EI group than in the AI group (RR 1.60; 95% CI 1.22-2.10). The rates of en bloc resection [odds ratio (OR) 0.57; 95% CI 0.41-0.78), complete resection (OR 0.37; 95% CI 0.25-0.57), and curative resection (OR 0.34; 95% CI 0.20-0.58) were significantly inferior in the EI group than in the AI group, whereas overall bleeding risk (RR 1.47; 95% CI 1.19-1.82) and procedure-related perforation rate (OR 2.04; 95% CI 1.56-2.68) were significantly higher in the EI group than in the AI group.

CONCLUSIONS

This meta-analysis suggests that the EI group showed acceptable long-term outcomes with local recurrence rate that was not significantly inferior, although the metachronous recurrence rate was higher compared with that in the AI group.

Endoscopic submucosal dissection for early gastric cancer with undifferentiated-type histology: A meta-analysis

AIM: To evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) with undifferentiated-type histology.

METHODS: A systematic literature review was conducted using the core databases. Complete resection, curative resection, en bloc resection, recurrence and adverse event rate were extracted and analyzed. A random effect model was applied. The methodological quality of the enrolled studies was assessed using the Newcastle-Ottawa Scale. Publication bias was evaluated using a funnel plot, the trim and fill method, Egger’s test, and a rank correlation test.

RESULTS: Fourteen retrospective studies between 2009 and 2014 were identified (972 EGC lesions with undifferentiated-type histology). The total en bloc and complete resection rates were estimated as 92.1% (95%CI: 87.4%-95.2%) and 77.5% (95%CI: 69.3%-84%), respectively. The total curative resection rate was 61.4% (95%CI: 44.5%-75.9%). The overall recurrence rate was 7.6% (95%CI: 3.4%-16%). Limited to histologically diagnosed expanded-criteria lesions, the en bloc and complete resection rates were 91.2% and 85.6%, respectively. The curative resection rate was 79.8%.

CONCLUSION: In this analysis, ESD is a technically feasible treatment modality for EGC with undifferentiated-type histology. Long-term studies are needed to confirm these therapeutic outcomes.

Suitability of the expanded indication criteria for the treatment of early gastric cancer by endoscopic submucosal dissection: Japanese multicenter large-scale retrospective analysis of short- and long-term outcomes

OBJECTIVE

The criteria for endoscopic resection for early gastric cancer include absolute and expanded indications. Consensus already exists for the absolute indications. However, the suitability of the expanded indications must be validated by long-term outcome analyses since such lesions have only recently become resectable with the development of endoscopic submucosal dissection. The aim of this study is to clarify the suitability of the expanded indications for the treatment of early gastric cancer with endoscopic submucosal dissection.

MATERIALS AND METHODS

The medical records of 1161 patients with early gastric cancers (1332 lesions) treated by endoscopic submucosal dissection and meeting the criteria for absolute or expanded indications without additional treatment with gastrectomy were divided into absolute indication group or expanded indication group.

RESULTS

Complete resection rates were 96.4% and 93.4% in absolute and expanded indication groups, respectively, with no significant differences between the groups. Delayed bleeding rates were significantly higher in the expanded indication group, whereas all cases were successfully managed conservatively. The 5-year overall survival and recurrence-free rates were 93.7%/99.77% and 90.49%/98.90% in the absolute and the expanded indication groups, respectively, with no significant differences between the groups for either measure. Multivariate analyses revealed that affected horizontal margin and tumor location were independent predictive factors for recurrence.

CONCLUSION

The expanded indication group showed excellent post-endoscopic submucosal dissection short-term and long-term outcomes compared with the absolute indications group, demonstrating that expanded indications are suitable for endoscopic submucosal dissection for early gastric cancer.

Long-term outcome comparison of endoscopic resection and surgery in early gastric cancer meeting the absolute indication for endoscopic resection

BACKGROUND

Endoscopic resection (ER) of early gastric cancer (EGC) meeting the absolute indication has excellent long-term outcomes.

OBJECTIVE

To compare long-term outcomes of ER with those of surgery in patients with EGC who met the absolute indication for ER.

DESIGN

Retrospective cohort study.

SETTING

A specialized center for the treatment of cancer.

PATIENTS AND INTERVENTIONS

We retrospectively reviewed data from patients who underwent gastrectomy or ER for EGC between 2002 and 2007. Gastric cancers were differentiated-type adenocarcinoma without ulceration confined to the mucosal layer and 2 cm or smaller in size.

MAIN OUTCOME MEASUREMENTS

The primary outcome was overall survival (OS). Metachronous cancer rates and adverse event rates were compared. Kaplan-Meier plots and Cox proportional hazard regression analyses were applied for comparisons. Differences in baseline characteristics were adjusted by propensity score.

RESULTS

Among 375 patients, 261 underwent ER and 114 underwent surgery. The median follow-up duration was 76.4 months. The 5-year OS rates did not significantly differ between the ER and surgery groups (95.7% vs 93.6%, respectively; P = .725 by log-rank test). There were no gastric cancer-related deaths in either group. Metachronous gastric cancer developed more frequently in the ER group (6.1%, 16/261) than in the surgery group (0.9%, 1/114) (P = .024). However, most patients (93.8%, 15/16) in the ER group were curatively treated with repeat ER. Adverse event rates were higher in the surgery group than those in the ER group (7.9% vs 2.7%, P = .028).

LIMITATIONS

Retrospective, single-center study.

CONCLUSIONS

The OS rate after ER for mucosal gastric cancer that met the absolute indication was comparable to that achieved with surgery. Although metachronous cancers were more common after ER, they were usually treatable and did not affect survival.

Outcome of endoscopic submucosal dissection for early gastric cancer of conventional and expanded indications: systematic review and meta-analysis

OBJECTIVE

Current guidelines for treating early gastric cancer (EGC) with endoscopic submucosal dissection (ESD) are being developed with broader criteria. This systematic review and meta-analysis aimed to assess the application of expanded indications (EIN) by comparing outcomes between conventional indication (CIN) and EIN groups.

METHODS

Literature databases were searched. Short-term outcomes, including endoscopic resection rates, complications and local recurrence, and long-term outcomes including gastric cancer-specific mortality and overall mortality were compared in the two groups.

RESULTS

In all, 13 studies were identified and evaluated. The EIN group had lower rates of en bloc (93.6% vs 97.0%, P < 0.0001), complete (87.8% vs 95.8%, P < 0.00001) and curative resection (82.4% vs 94.0%, P < 0.00001) than the CIN group. The rates of delayed bleeding and perforation were both significantly higher in the EIN group (3.9% vs 2.8%, P = 0.04 and 3.9% vs 1.8%, P < 0.0001). Local recurrence rates were 0.6% in the CIN group and 1.5% in the EIN group (P = 0.03). There were no significant differences between the two groups in the gastric-cancer specific mortality (P = 0.22) and the overall mortality (P = 0.37).

CONCLUSIONS

Long-term mortality in the EIN group did not significantly differ from those in the CIN group, although the EIN group was associated with more unfavorable short-term outcomes. Thus, ESD could be recommended as an effective therapy for EGC of EIN.

Clinical outcomes of endoscopic submucosal dissection for early stage esophagogastric junction cancer: a systematic review and meta-analysis

BACKGROUND

Although endoscopic submucosal dissection has become widely used for the management of selected cases of early gastric cancer, the effects of endoscopic submucosal dissection for esophagogastric junction cancer have not been fully evaluated.

METHODS

Medline, Embase, and the Cochrane Library were searched using the primary keywords "endoscopic submucosal dissection," "ESD," "endoscopic resection," "esophagogastric junction," "gastroesophageal junction," and "Barrett." Six short-term clinical outcomes and three long-term oncologic outcomes were extracted.

RESULTS

A total of six studies provided data on 359 early stage esophagogastric junction cancers treated with endoscopic submucosal dissection. The pooled estimate of en bloc resection and complete resection was 98.6% (95% confidence interval 95.9-99.6%) and 87.0% (95% confidence interval 79.7-92.0%), respectively. The pooled estimate of stenosis was 6.9% (95% confidence interval 3.2-14.0%). In 269 lesions with curative resection, there was no local recurrence or distant metastasis. In contrast, three local recurrences and two distant metastases occurred in 90 lesions with non-curative resection.

CONCLUSIONS

Endoscopic submucosal dissection for early stage esophagogastric junction cancer is a feasible treatment option with high en bloc resection, complete resection rates and an acceptable range of complications. When curative resections are achieved, good oncologic outcomes are likely in the management of early stage esophagogastric junction cancer by endoscopic submucosal dissection.

Minimally invasive surgery in gastric cancer

Minimally invasive surgery for gastric cancer has rapidly gained popularity due to the early detection of early gastric cancer. As advances in instruments and the accumulation of laparoscopic experience increase, laparoscopic techniques are being used for less invasive but highly technical procedures. Recent evidence suggests that the short- and long-term outcomes of minimally invasive surgery for early gastric cancer and advanced gastric cancer are comparable to those of conventional open surgery. However, these results should be confirmed by large-scale multicenter prospective randomized controlled clinical trials.

Clinical safety of endoscopic submucosal dissection compared with surgery in elderly patients with early gastric cancer: a propensity-matched analysis

BACKGROUND

Little is known about the clinical and oncologic outcomes of endoscopic submucosal dissection (ESD) compared with surgery in elderly patients with early gastric cancer (EGC).

OBJECTIVE

To evaluate the clinical and oncologic outcomes of ESD compared with surgery in elderly patients with EGC of an expanded indication.

DESIGN

Retrospective study with propensity-matched analysis.

SETTING

University-affiliated tertiary-care hospital, Seoul, South Korea.

PATIENTS

A total of 518 patients 70 years of age or older with initial-onset EGC.

INTERVENTIONS

ESD and surgery.

MAIN OUTCOME MEASUREMENTS

Clinical outcomes, disease-free survival, and overall survival.

RESULTS

In a propensity-matched analysis of 132 pairs, the length of hospital stay of the ESD group was shorter than that of the surgery group (median [interquartile range], 4 [3-4] vs 9 [7-11] days; P < .001). Intensive care unit admission occurred in the surgery group only (7 patients [5.3%]). Two surgery-related deaths occurred in the surgery group (1 splenic artery bleeding and 1 anastomosis site leakage). During follow-up, metachronous lesions developed more often in the ESD group than in the surgery group (12 vs 2 lesions, P = .004). All recurred lesions were successfully treated endoscopically except for 3 patients who refused additional treatment. Overall survival did not differ between the 2 groups (P = .280).

LIMITATIONS

Nonrandomized, retrospective study.

CONCLUSIONS

ESD is a safe procedure in elderly patients with EGC. Although the risk of metachronous lesions is higher in patients who undergo ESD than in those who undergo surgery, overall survival did not differ between the patients who undergo ESD and surgery.

Endoscopic resection for undifferentiated early gastric cancer: focusing on histologic discrepancies between forceps biopsy-based and endoscopic resection specimen-based diagnosis

BACKGROUND

Before endoscopic resection (ER), a considerable number of undifferentiated early gastric cancer (UD-EGC) cases were initially diagnosed as atypical glands, dysplasia, or differentiated EGC (D-EGC) based on forceps biopsy specimens. As UD-EGC carries a high risk of resection margin involvement, identifying the predictive factors for UD-EGC cases with histologic discrepancy (HD) is of clinical importance.

AIMS

To investigate the outcomes of ER for UD-EGC and to identify the predictive factors for UD-EGC with HD.

METHODS

Among 2,194 EGC lesions treated by ER, 59 lesions were finally diagnosed as UD-EGC and 50 UD-EGC cases showed HD. The demographic and endoscopic characteristics were compared between D-EGC and UD-EGC with HD, and the predictive factors for the latter were investigated among cases of forceps biopsy-based diagnosis of atypical glands, dysplasia, or D-EGC.

RESULTS

UD-EGC showed significantly higher rate of lateral margin involvement compared to D-EGC (18.6 vs. 3.4%). Among the UD-EGC cases meeting the expanded criteria and not involving additional surgery, no local or extragastric tumor recurrence was observed during the median follow-up of 27.5 months. Multivariate analysis demonstrated that age (≤60 years), female gender, gastric body, flat or depressed type, and tumor size (>2 cm) were independent predictive factors for UD-EGC with HD among cases of forceps biopsy-based diagnosis of atypical glands, dysplasia, or D-EGC.

CONCLUSIONS

For lesions with predictive factors for UD-EGC with HD, a circumferential mapping biopsy before ER or wide marking during ER could be considered to avoid the potential risk of incomplete resection.

Predictors of lymph node metastasis in patients with non-curative endoscopic resection of early gastric cancer

BACKGROUND

Although surgery is recommend for non-curative endoscopic resection of early gastric cancer (EGC), only a part of patients are found to have lymph node (LN) metastasis. This study aimed to identify the predictors of LN metastasis in patients with non-curative endoscopic resection.

METHODS

Between April 2005 and July 2013, consecutive patients who received non-curative endoscopic resection and then underwent gastrectomy with lymphadenectomy or followed at least 1 year with abdominal computed tomography were retrospectively enrolled at a single tertiary hospital. Non-curative resection was defined as a resection beyond the expanded criteria in pathologic mapping. The predictors for LN metastasis were identified by fitting a multivariate logistic regression model.

RESULTS

Among the 1783 consecutive patients who received endoscopic resection of EGC, non-curative resection was performed in 323 (18.1%) patients. Of these patients, a total of 267 patients were enrolled, and the rate of LN metastasis was 6.7% (18/267). In multivariate analysis, venous invasion [odds ratio (OR), 7.83; 95% confidence interval (CI) 2.20-27.86; p = 0.001], sm2 invasion (tumor invasion ≥500 µm into submucosa; OR 4.98; 95% CI 1.34-18.47; p = 0.016), or antral tumor location (OR 12.65; 95% CI 1.57-102.00; p = 0.017) were independent predictors for LN metastasis. The rates of LN metastasis were 1.1% (95% CI 0-2.7) for patients with one or no predictor and 17.8% (95% CI 9.7-25.8) for those with two or more predictors.

CONCLUSIONS

Additional gastrectomy with lymphadenectomy after non-curative endoscopic resection of EGC is recommended for the patients with two or more identified predictors. However, close follow-up without immediate surgery might be considered cautiously for those with only one or no predictor.

Long-term efficacy of endoscopic submucosal dissection compared with surgery for early gastric cancer: a retrospective cohort study

Background/Aims

This study aimed to compare the outcomes of endoscopic submucosal dissection (ESD) and gastrectomy based on the two sets of indications for ESD, namely guideline criteria (GC) and expanded criteria (EC).

Methods

Between January 2004 and July 2007, 213 early gastric cancer (EGC) patients were enrolled in this study. Of these patients, 142 underwent ESD, and 71 underwent gastrectomy. We evaluated the clinical outcomes of these patients according to the criteria.

Results

The complication rates in the ESD and gastrectomy groups were 8.5% and 28.2%, respectively. The duration of hospital stay was significantly shorter in the ESD group than the gastrectomy group according to the GC and EC (p<0.001 and p<0.001, respectively). There was no recurrence in the ESD and gastrectomy groups according to the GC, and the recurrence rates in the ESD and gastrectomy groups were 4.7% and 0.0% according to the EC, respectively (p=0.279). The occurrence rates of metachronous cancer in the ESD and gastrectomy groups were 5.7% and 5.0% according to the GC (p=1.000) and 7.5% and 0.0% according to the EC (p=0.055), respectively.

Conclusions

Based on safety, duration of hospital stay, and long-term outcomes, ESD may be an effective and safe first-line treatment for EGC according to the EC and GC.

Endoscopic Resection for Early Gastric Cancer beyond Absolute Indication with Emphasis on Controversial Issues

Endoscopic resection is the established treatment for early gastric cancer in selected patients with negligible risk of lymph node metastasis ('absolute indication'). Based on clinical observations and large pathological databases, expanding indications for endoscopic resection beyond absolute indication has been tried in Japan and Korea. However, controversies exist regarding the safety of treating early gastric cancer beyond absolute indication in terms of pathological evaluation of the resected specimen, definition of expanded indication, discrepancy between pre-endoscopic resection and post-endoscopic resection diagnoses of gastric neoplasm, and the best strategy for cases with non-curative resection. In this brief review, current evidence and clinical experience regarding issues of endoscopic resection beyond absolute indication will be summarized.

Long-term outcome of extended endoscopic submucosal dissection for early gastric cancer with differentiated histology

Endoscopic mucosal resection was introduced in the 1990s, and endoscopic submucosal dissection (ESD) in 2003. Currently, ESD is becoming the main procedure for the resection of early gastric cancer (EGC) and is leading to the development of extended indications for endoscopic resection. Many reports showed that the endoscopic and oncologic outcome of endoscopic treatment in the extended indication group was acceptable in terms of curability and safety. Especially, ESD showed better results to remove extended indication EGCs with relatively high resection rate and low local recurrence rate. However, more long-term follow-up data are needed for clinical application of the extended criteria of ESD due to the risk of lymph node metastasis. We should also keep in mind that accurate diagnosis, characterization of the lesion, and proper appreciation of technical aspects are most essential in therapeutic endoscopy.

Highlights of international digestive endoscopy network 2013

Rapid advances in the technology of gastrointestinal endoscopy as well as the evolution of science have made it necessary for us to continue update in either various endoscopic techniques or state of art lectures relevant to endoscopy. International Digestive Endoscopy Network (IDEN) 2013 was held in conjunction with Korea-Japan Joint Symposium on Gastrointestinal Endoscopy (KJSGE) during June 8 to 9, 2013 at Seoul, Korea. Two days of impressive scientific program dealt with a wide variety of basic concerns from upper gastrointestine (GI), lower GI, pancreaticobiliary endoscopy to advanced knowledge including endoscopic submucosal dissection forum. IDEN seems to be an excellent opportunity to exchange advanced information of the latest issues on endoscopy with experts from around the world. In this special issue of Clinical Endoscopy, we prepared state of art review articles from contributing authors and the current highlights will skillfully deal with very hot spots of each KJSGE, upper GI, lower GI, and pancreaticobiliary sessions by associated editors of Clinical Endoscopy.