Endoscopic resection of early gastric cancer treated by guideline and expanded National Cancer Centre criteria

Evaluation and Management of Gastric Superficial Neoplastic Lesions

Gastric cancer is one of the most common and lethal cancers in the world. In Portugal, it is a major health problem presenting one of the highest incidence rates among European countries. In most Western countries, gastric cancer is generally diagnosed in advanced stages. Nevertheless, with the widespread use of upper endoscopy, gastric superficial neoplastic lesions are being increasingly recognized and diagnosed. However, there are no clear recommendations regarding who should be screened for its presence and only recently guidelines concerning the evaluation and management of these lesions were published. In this review, we summarize the current scientific evidence regarding diagnosis and management of gastric superficial neoplastic lesions. Topics like screening, diagnosis, endoscopic evaluation, management, treatment, pathologic evaluation and follow-up of patients with these lesions are covered and areas of future research are discussed. Whenever possible, evidence-based recommendations are made, and on the other cases expert opinion is presented.

Gastric Cancer in Southern Europe: High-Risk Disease

Gastric cancer is an aggressive disease. Several risk factors are involved in gastric cancer pathogenesis, likely Helicobacter pylori (H. pylori) infection, genetic factors in hereditary syndromes, lifestyle, and diet. However, well-implemented screening strategies are lacking in most countries, including those in Southern Europe. Nevertheless, gastric cancer outcomes are better in some Southern European countries than in others, likely because of the incidence and distribution of different histologic types. Robotic surgery has been gaining favor as a treatment of early-stage disease, and the need for perioperative chemotherapy or adjuvant chemoradiotherapy (CRT) for locally advanced disease has been debated. In the metastatic setting, trastuzumab in combination with chemotherapy has helped to extend survival compared with chemotherapy alone for HER2-positive disease. This article will describe how gastric cancer is assessed and treated in Southern Europe in an attempt to correlate these approaches from a global perspective.

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.

Short-Term Outcomes of Endoscopic Submucosal Dissection in Patients with Early Gastric Cancer: A Prospective Multicenter Cohort Study

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) is an effective treatment for early gastric cancer (EGC) that has demonstrated a minimal risk of lymph node metastasis in retrospective studies. We sought to prospectively evaluate the short-term outcomes of ESD treatment in EGCs.

METHODS

A prospective multicenter cohort study of neoplasms 3 cm or less in diameter at endoscopic size evaluation was performed in 12 Korean ESD study grouprelated university hospitals and the National Cancer Center. Resected specimens were evaluated by the central pathologic review board.

RESULTS

A patient cohort (n=712) with a total of 737 EGCs was analyzed. The margin-free en bloc resection rate was 97.3%, and curative resection of 640 lesions (86.8%) was achieved. Lower curative resection rates were associated with lesions 2 to 3 cm in size prior to ESD compared with lesions 2 cm or less in size (78.6% vs 88.1%, respectively, p=0.009). Significant factors associated with noncurative resection were moderately or poorly differentiated histological type, posterior wall tumor location, tumor size larger than 3 cm, ulceration, and submucosal invasion. Delayed bleeding occurred in 49 patients (6.9%), and 12 patients (1.7%) exhibited perforations.

CONCLUSIONS

ESD is an effective treatment with a high curative resection rate for EGCs that meets relatively conservative pre-ESD indications. Long-term survival outcomes should be evaluated in followup studies.

Risk factors for lymph node metastasis and long-term outcomes of patients with early gastric cancer after non-curative endoscopic submucosal dissection

BACKGROUND

The long-term outcomes after non-curative gastric endoscopic submucosal dissection (ESD) are still unknown. We aimed to clarify the pathological risk factors for lymph node metastasis (LNM) of early gastric cancer (EGC) and the long-term outcomes among patients who were judged to have had non-curative ESD.

METHODS

From September 2002 to December 2012, 506 patients who were judged to have had non-curative gastric ESD were enrolled and classified into two groups: (1) those who subsequently underwent additional surgical resection (surgical group, n = 323) and (2) those followed up without additional surgical resection (nonsurgical group, n = 183). We analyzed pathological risk factors for LNM of EGC in the surgical group. Additionally, we compared long-term outcomes in the two groups.

RESULTS

LNM was found pathologically in 9.3 % of the surgical group (30/323) at the additional surgical resection after non-curative ESD. In the multivariate logistic regression analysis, lymphovascular invasion (LVI) was an independent risk factor for LNM in the surgical group (odds ratio 8.57, 95 % confidence interval 2.76-38.14, P < 0.0001). The 5-year cause-specific survival rate was similar in the surgical and nonsurgical groups (98.7 and 96.5 %, respectively; log-rank test, P = 0.07). In contrast, the 5-year cause-specific survival rate of patients with LVI in the surgical group was better than that in the nonsurgical group (98.2 and 79.1 %, respectively; log-rank test, P < 0.0001).

CONCLUSIONS

A detailed assessment of LVI is essential to the pathological evaluation of endoscopically resected specimens. An additional surgical resection should be strongly recommended for patients with LVI.

Incidence of and risk factors for metachronous gastric cancer after endoscopic resection and successful Helicobacter pylori eradication: results of a large-scale, multicenter cohort study in Japan

BACKGROUND

A previous multicenter prospective randomized study from Japan showed that Helicobacter pylori eradication reduced the development of metachronous gastric cancer (MGC) after endoscopic resection for early gastric cancer. MGC risk, however, is not eliminated; yet few studies have evaluated its long-term incidence and risk factors. In this study, we investigated the incidence of and risk factors for MGC in patients who underwent endoscopic resection for early gastric cancer with successful H. pylori eradication.

METHODS

A total of 594 patients who underwent endoscopic resection for early gastric cancer and successful H. pylori eradication at three institutions (National Cancer Center Hospital, University of Tokyo Hospital, and Wakayama Medical University Hospital) were analyzed retrospectively. Annual endoscopic surveillance was performed after initial endoscopic resection. MGC was defined as a gastric cancer newly detected at least 1 year after successful H. pylori eradication.

RESULTS

Ninety-four MGCs were detected in 79 patients during the 4.5-year median follow-up period. Kaplan-Meier analysis showed the cumulative incidence of MGC 5 years after successful H. pylori eradication was 15.0 %; the incidence of MGC calculated by use of the person-year method was 29.9 cases per 1000 person-years. Multivariate analysis using the Cox proportional hazards model revealed that male sex, severe gastric mucosal atrophy, and multiple gastric cancers before successful H. pylori eradication were independent risk factors for MGC. Eleven percent of MGCs (10 of 94) were detected more than 5 years after successful H. pylori eradication.

CONCLUSION

Surveillance endoscopy for MGC in patients who have undergone endoscopic resection for early gastric cancer should be performed even after successful H. pylori eradication.

Endoscopic prediction of recurrence in patients with early gastric cancer after margin-negative endoscopic resection

BACKGROUND AND AIM

Although follow-up endoscopy is routinely performed after endoscopic resection (ER) for early gastric cancer (EGC), it remains unclear whether resection scar biopsies should also be taken. This study sought to predict local recurrence at the ER scar on the basis of endoscopic criteria after margin-negative EGC resection and to determine the necessity of taking scar biopsies.

METHODS

All consecutive patients with EGC who underwent margin-negative ER in June 1995 to December 2011 and developed recurrence at the scar were identified. Each case was matched by four controls with EGC and margin-negative ER but without local recurrence for age, sex, and en-bloc resectability (en-bloc vs. piecemeal resection). Endoscopic data were reviewed by consensus of two endoscopists. Key endoscopic criteria were gross morphology (evenly elevated, unevenly elevated, and flat), hyperemic change, mucosal defect, and spontaneous bleeding.

RESULTS

Of 3037 cases, which underwent margin-negative ER, 22 developed local recurrence (mean age, 63.8 years; 72.9% male). En-bloc resection was achieved in 20 of the 22 (90.9%). Flat endoscopic morphology without hyperemic changes predicted non-recurrence at the scar with a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 95.5%, 68.2%, 2.6%, 99.94%, and 73.6%, respectively. For patients who underwent en-bloc resection for differentiated EGC, these values were 100%, 71.4%, 3.0%, 100%, and 75.8%, respectively.

CONCLUSIONS

Routine follow-up biopsies may be unnecessary when follow-up endoscopy reveals flat mucosa without hyperemic changes at the scar, especially for en-bloc resected and differentiated EGCs.

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.

How to Interpret the Pathological Report before and after Endoscopic Submucosal Dissection of Early Gastric Cancer

Possible lymph node metastasis (LNM) and residual cancer are major concerns in endoscopic submucosal dissection (ESD) for early gastric cancer. To reduce the risk of LNM and cancer recurrence, the proper indications for ESD should be considered. Histology, size, depth of invasion, and presence of ulceration should be thoroughly evaluated before proceeding with ESD. However, with incomplete information, discrepancies often arise between the pathological diagnosis based on the forceps biopsy and that based on the totally resected specimen. In addition, the presence of lymphovascular involvement and histological homogeneity can be clarified only after ESD. If the pathological diagnosis changes after ESD, we should reevaluate the curativeness and reformulate the goal of treatment. Additional surgery is a reasonable strategy for non-curative ESD, but a patient's other health conditions should also be considered. It is simple to read pathological reports before and after ESD, but it can be a complicated art to interpret the report and formulate an optimal approach. In this review, various considerations regarding the pathological diagnosis will be discussed.

Loss of OLFM4 promotes tumor migration through inducing interleukin-8 expression and predicts lymph node metastasis in early gastric cancer

Endoscopic surgery is increasingly used for early gastric cancer (EGC) treatment worldwide, and lymph node metastasis remains the most important risk factor for endoscopic surgery in EGC patients. Olfactomedin 4 (OLFM4) is mainly expressed in the digestive system and upregulated in several types of tumors. However, the role of OLFM4 in EGC has not been explored. We evaluated OLFM4 expression by immunohistochemical staining in 105 patients with EGC who underwent gastrectomy. The clinicopathological factors and OLFM4 expression were co-analyzed to predict lymph node metastasis in EGC. The metastatic mechanism of OLFM4 in gastric cancer was also investigated. We found that OLFM4 was upregulated in EGC tumor sections, and relatively low expression of OLFM4 was observed in patients with lymph node metastasis. OLFM4 expression as well as tumor size and differentiation were identified as independent factors, which could be co-analyzed to generate a better model for predicting lymph node metastasis in EGC patients. In vitro studies revealed that knockdown of OLFM4 promoted the migration of gastric cancer cells through activating the NF-κB/interleukin-8 axis. Negative correlation between OLFM4 and interleukin-8 expression was also observed in EGC tumor samples. Our study implies that OLFM4 expression is a potential predictor of lymph node metastasis in EGC, and combing OLFM4 with tumor size and differentiation could better stratify EGC patients with different risks of lymph node metastasis.

Rates of lymph node metastasis and survival in T1a gastric adenocarcinoma in Western populations

BACKGROUND AND AIMS

EMR and endoscopic submucosal dissection (ESD) are widely accepted in Asia for treatment of early gastric cancer (EGC). Few studies have examined lymph node (LN) metastasis of EGC in Western populations. We sought to examine EGC and LN metastasis in a heterogeneous Western population.

METHODS

Patients with surgically resected, histologically confirmed American Joint Committee on Cancer T1a gastric adenocarcinoma were identified in the Surveillance, Epidemiology, and End Results (SEER) database from 2002 to 2012. Patients were excluded if they had stage IV disease, had multiple primary cancers, or received neoadjuvant therapy. Rates of LN metastasis were calculated, and survival analyses were performed.

RESULTS

Of 923 patients in the cohort, 72 (7.8%) had at least 1 positive LN on final pathology. When stratified by race, Asian/Pacific Islanders (APIs) demonstrated the lowest rate of LN metastases (n = 17/327, 5.2%), followed by Hispanics (n = 12/171, 7.0%), whites (n = 27/278, 9.7%), and blacks (n = 16/147, 10.9%). The highest rates of stage IA disease were observed in API (93.9%) and Hispanic (92.4%) patients, followed by white (89.9%) and black (87.1%) patients (P = .04). Survival analysis of T1a gastric cancer patients by race/ethnicity showed that 5-year overall survival was highest for API patients (API, 88%; Hispanic, 81%; black, 79%; and white, 77%; P < .01).

CONCLUSIONS

The rate of LN metastasis in T1a gastric cancers in the United States is higher than the rates reported in Asia. Survival outcomes in T1a gastric cancers varied significantly by race, suggesting that definitive endoscopic treatment may not be appropriate for all patients in the United States.

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.

Clinical outcomes of and management strategy for perforations associated with endoscopic submucosal dissection of an upper gastrointestinal epithelial neoplasm

INTRODUCTION

Perforation is one of the major complications of endoscopic submucosal dissection (ESD). In the present study, we investigated the clinical outcomes of and management strategies for ESD-related perforations.

METHODS

Between February 2010 and April 2014, a total of 3821 patients who underwent ESD for an upper gastrointestinal epithelial neoplasm were analyzed using the Yonsei University Severance Hospital database. Clinical outcomes of and management strategies for perforations in 90 patients (2.4 %) were analyzed. The risk factors for the development of perforation were also investigated.

RESULTS

The mean age of our subjects was 64.7 ± 12.2 years (male to female ratio, 3.2:1), and the mean size of the resected specimens was 39.4 ± 12.5 mm. Endoscopically visible perforations (visible perforation group) were noted in 74 of the 90 patients (82.2 %), and clinically suspected perforations (suspected perforation group) were noted in 16 patients (17.8 %). Immediate closure with endoclips was attempted in cases with a visible perforation and was successful in 72 (97.3 %) cases. Two patients in whom endoscopic closure failed underwent surgery. Conservative care, including fasting and intravenous antibiotic administration, was attempted in the suspected perforation group, and all the patients were treated successfully without surgery. The mean durations of fasting, antibiotic treatment, and hospital stay were 3.8 ± 3.1, 6.8 ± 4.2, and 8.7 ± 5.3 days, respectively. Subgroup analysis of perforation type (visible perforation vs. suspected perforation) revealed no significant difference in the clinical course. Tumor location at the upper or middle third of the stomach was significantly associated with perforation.

CONCLUSION

Most of the ESD-related perforations in upper gastrointestinal epithelial neoplasm could be managed successfully in a non-surgical manner under strict monitoring.

Gastric cancer: Current status of lymph node dissection

D2 procedure has been accepted in Far East as the standard treatment for both early (EGC) and advanced gastric cancer (AGC) for many decades. Recently EGC has been successfully treated with endoscopy by endoscopic mucosal resection or endoscopic submucosal dissection, when restricted or extended Gotoda's criteria can be applied and D1+ surgery is offered only to patients not fitted for less invasive treatment. Furthermore, two randomised controlled trials (RCTs) have been demonstrating the non inferiority of minimally invasive technique as compared to standard open surgery for the treatment of early cases and recently the feasibility of adequate D1+ dissection has been demonstrated also for the robot assisted technique. In case of AGC the debate on the extent of nodal dissection has been open for many decades. While D2 gastrectomy was performed as the standard procedure in eastern countries, mostly based on observational and retrospective studies, in the west the Medical Research Council (MRC), Dutch and Italian RCTs have been conducted to show a survival benefit of D2 over D1 with evidence based medicine. Unfortunately both the MRC and the Dutch trials failed to show a survival benefit after the D2 procedure, mostly due to the significant increase of postoperative morbidity and mortality, which was referred to splenopancreatectomy. Only 15 years after the conclusion of its accrual, the Dutch trial could report a significant decrease of recurrence after D2 procedure. Recently the long term survival analysis of the Italian RCT could demonstrate a benefit for patients with positive nodes treated with D2 gastrectomy without splenopancreatectomy. As nowadays also in western countries D2 procedure can be done safely with pancreas preserving technique and without preventive splenectomy, it has been suggested in several national guidelines as the recommended procedure for patients with AGC.

Comparison of O-Type HybridKnife to Conventional Knife in Endoscopic Submucosal Dissection for Gastric Mucosal Lesions

Endoscopic submucosal dissection (ESD) has been accepted as a minimal invasive alternative to surgery for localized superficial gastrointestinal neoplasms recently. However, the procedure remains to be technically challenging and time consuming. A new dissecting knife with partially insulated tip has been recently developed with built-in injection capability. The purpose of this study was to investigate whether the efficiency of ESD procedure could be improved with this new device. A total of 78 patients, who underwent ESD with gastric mucosal lesions including flat type polyps, adenoma or early gastric cancer, were randomly assigned to either ESD with O-type HybridKnife or conventional ESD knives without waterjet. Procedure time and related factors of ESD were analyzed. ESD procedure time was 43.0 (interquartile range, IQR 27.0-60.0) minutes in HybridKnife group compared to 60.5 (IQR 44.0-86.3) minutes in the control group (P = 0.001). There was no difference in the clinical outcome and the adverse event rate. The former demonstrated more favorable results in lesions ≤4 cm of specimen size (P ≤ 0.0001) and when located in the distal stomach (P = 0.001), also in lesions with fibrosis (P = 0.008). Multivariate regression analysis showed that O-type Knife (P ≤ 0.0001), specimen size (P ≤ 0.0001), and fibrosis (P ≤ 0.0001) were independent predictors of procedure time. The O-type HybridKnife yielded faster procedure time compared to the conventional knives in gastric ESD with a similar safety profile.

Pretreatment Gastric Lavage Reduces Postoperative Bleeding after Endoscopic Submucosal Dissection for Gastric Neoplasms

Aim

For patients receiving endoscopic submucosal dissection (ESD), there is urgent need pertaining to the prevention of postoperative bleeding. We conducted a retrospective propensity score-matched study that evaluated whether pre-ESD gastric lavage prevents postoperative bleeding after ESD for gastric neoplasms.

Methods

From September 2002 to October 2015, the 760 consecutive patients receiving ESD for gastric neoplasm were enrolled and data regarding them were retrospectively analyzed. All patients received conventional preventive treatment against delayed bleeding after ESD, including the administration of proton pump inhibitor and preventive coagulation of visible vessels, at the end of the ESD procedure.

Results

Pre-ESD risk factors for postoperative bleeding included tumor size and no gastric lavage. Using multivariate analysis tumor size >2.0 cm (HR 2.90, 95% CI 1.65–5.10, p = 0.0002) and no gastric lavage (HR 3.20, 95% CI 1.13–9.11, p = 0.029) were found to be independent risk factors. Next, we evaluated the effect of gastric lavage on the prevention of post-ESD bleeding using a propensity score-matching method. A total of 284 subjects (142 per group) were selected. Adjusted odds ratio of gastric lavage for post-ESD bleeding was 0.25 (95% CI 0.071–0.886, p = 0.032).

Conclusion

Pretreatment gastric lavage reduced postoperative bleeding in patients receiving ESD for gastric neoplasm.

Endoscopic submucosal dissection

ESD is an established effective treatment modality for premalignant and early-stage malignant lesions of the stomach, esophagus, and colorectum. Compared with EMR, ESD is generally associated with higher rates of en bloc, R0, and curative resections and a lower rate of local recurrence. Oncologic outcomes with ESD compare favorably with competing surgical interventions, and ESD also serves as an excellent T-staging tool to identify noncurative resections that will require further treatment. ESD is technically demanding and has a higher rate of adverse events than most endoscopic procedures including EMR. As such,sufficient training is critical to ensure safe conduct and high-quality resections. A standardized training model for Western endoscopists has not been clearly established,but will be self-directed and include courses, animal model training, and optimally an observership at an expert center.Numerous dedicated ESD devices are now available in the United States from different manufacturers. Although the use of ESD in the United States is increasing, issues related to technical difficulty, limited training opportunities and mentors, risk of adverse events, long procedure duration,and suboptimal reimbursement may limit ESD adoption in the United States to a modest number of academic referral centers for the foreseeable future.

Lymph node metastasis in differentiated-type early gastric cancer: a single-center retrospective analysis of surgically resected cases

BACKGROUND

Lymph node metastasis (LNM) from early gastric cancer (EGC) is rare, especially for differentiated-type EGC. However, LNM has been reported in a few cases after endoscopic curative resection of differentiated-type EGC. This study aimed to evaluate LNM risk factors to identify those that should be considered during the preoperative evaluation of differentiated-type EGC.

PATIENTS AND METHODS

A total of 976 EGC patients who underwent radical gastrectomy were reviewed in this study. Univariate and multivariate analyses were used to analyze the predictive factors for LNM based on the histology of the differentiated-type EGC cases.

RESULTS

Differentiated-type EGC was observed in 59% of the cases. The rate of LNM was 6.6% (38/576 patients) in the differentiated-type EGC cases. Macroscopic shape, ulcers, tumor size, deeper invasion and lymphovascular invasion were shown to be related to LNM in differentiated-type EGC. Multivariate analysis revealed that size, depth, ulceration and lymphovascular invasion were independent predictors of LNM in differentiated-type EGC. When lymphovascular invasion was absent, the presence of one or more of the risk factors of ulcer lesions, tumor size >30 mm and submucosal invasion increased the rate of LNM. Thirteen patients who underwent radical gastrectomy were shown to have differentiated-type EGC with LNM that met the standard and expanded criteria of endoscopic submucosal dissection.

CONCLUSIONS

As endoscopic resection is widely used, it is important to clarify the clinical significance of LNM in differentiated-type EGC and to screen for LNM with this incidence in mind and to follow the clinical courses of such cases, especially in China.

High rate of 5-year survival among patients with early gastric cancer undergoing curative endoscopic submucosal dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) has been used to treat patients with early gastric cancers (EGCs), including large and ulcerative lesions. Few published data exist on the long-term outcomes of this treatment with median follow-up periods of over 5 years; we therefore aimed to assess the long-term outcomes of EGC patients undergoing ESD.

METHODS

A total of 1,956 consecutive patients with 2,210 EGC lesions at initial onset underwent ESD with curative intent at our hospital from 1999 to 2006. We performed a retrospective analysis of the 5-year survival of EGC patients undergoing curative ESD for absolute indications or for expanded indications.

RESULTS

For the pathological curability, curative ESD for absolute indications, curative ESD for expanded indications of differentiated-type EGC, and curative ESD for undifferentiated-type EGC were achieved in 781, 713, and 43 patients, respectively. The median follow-up period was 83.3 months. Among the 1,537 patients, there were only two patients with recurrence, including one who developed a regional lymph node (LN) metastasis and one who developed a distant LN metastasis with local recurrence resulting in gastric cancer-related death. Seven died from metachronous gastric cancers. The 5-year rates of overall survival, disease-specific survival, and relative survival were 92.6, 99.9, and 105.0%, respectively.

CONCLUSIONS

Based on the high rate of 5-year survival among EGC patients undergoing curative ESD for absolute indications or for expanded indications in the largest patient series with a median follow-up period of over 5 years, ESD could be employed as a standard treatment for EGC lesions.

Effect of additional surgery after noncurative endoscopic submucosal dissection for early gastric cancer

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) is a standard treatment for early gastric cancer (EGC) without lymph node metastasis. However, some patients undergo noncurative ESD. The aim of the present study was to assess the long-term clinical outcomes of noncurative ESD with or without additional surgery.

PATIENTS AND METHODS

We investigated the chart data from all patients who had undergone ESD for EGC at Saga Medical School Hospital and Saga Prefectural Medical Centre Koseikan between 2001 and 2012. A total of 957 cases (1047 lesions) of EGC underwent ESD, and 99 had noncurative ESD. In total, 20 cases were excluded because their follow-up period was < 3 years. We divided the patients into observation and additional surgery groups, and we compared the survival rate and related factors between the groups.

RESULTS

After noncurative ESD, 28 /79 patients (35.4 %) underwent additional surgery and 51/79 (64.6 %) were followed up without surgery. The average age of patients in the observation group was higher than that of the additional surgery group (75.9 vs. 71.6 years; P = 0.03). The incidence of hypertension was significantly higher in the observation group compared with the additional surgery group (51.0 vs. 25.9 %; P = 0.03). The overall survival rate of the additional surgery group was longer than that of the observation group. However, only one patient died from gastric cancer in the observation group. The disease-specific survival rate did not differ significantly between the groups.

CONCLUSIONS

It might be acceptable to follow up without additional surgery for some patients with comorbidity and who were elderly after noncurative ESD for EGC.

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.

Seom guidelines for the treatment of gastric cancer 2015

Gastric cancer is the fourth cause of death by cancer in Spain and a significant medical problem. Molecular biology results evidence that gastroesophageal junction tumors and gastric cancer should be considered as two independent entities with a different prognosis and treatment approach. Endoscopic resection in very early tumors is feasible. Neoadjuvant and adjuvant therapy in locally advanced resectable tumor increase overall survival and should be considered standard treatments. In stage IV tumors, platinum–fluoropyrimidine-based schedule, with trastuzumab in HER2-overexpressed tumors, is the first-line treatment. Different therapies in second line have demonstrated in randomized studies their clear benefit in survival improvement.

Aberrant metastatic behavior and particular features of early gastric cancer

In this paper, we have focused on the metastatic behavior of EGC and its particularities. The main factors that are currently considered as predictors of the metastatic behavior and that are used in the therapeutic decision (endoscopic resection vs surgical removal) are the tumor size (upper or bellow 2 cm), depth of infiltration, angiolymphatic invasion, the presence or absence of ulceration, and histologic type (undifferentiated vs differentiated carcinomas). However, most of the metastatic cases were published as case reports or case series. This is the reason why a proper estimation of metastatic risk in EGC is not well known. To date, 79 cases presenting bone metastases, three reports of brain metastases, and one EGC that was associated with skin metastasis were published. However, occult metastasis, lymph node micrometastasis, and skip metastasis can also occur and should be identified. Making a synthesis of the literature data that is correlated with our experience, we finally proposed the inclusion of the six Japanese subgrouping system, tumor size, angiolymphatic invasion, and micrometastasis as components of the pTNM staging system, which should be particularly adapted for EGC.

Cooperative laparoscopic endoscopic and hybrid laparoscopic surgery for upper gastrointestinal tumors: Current status

AIM

To investigate the cooperative laparoscopic and endoscopic techniques used for the resection of upper gastrointestinal tumors.

METHODS

A systematic research of the literature was performed in PubMed for English and French language articles about laparoscopic and endoscopic cooperative, combined, hybrid and rendezvous techniques. Only original studies using these techniques for the resection of early gastric cancer, benign tumors and gastrointestinal stromal tumors of the stomach and the duodenum were included. By excluding case series of less than 10 patients, 25 studies were identified. The study design, number of cases, tumor pathology size and location, the operative technique name, the endoscopy team and surgical team role, operative time, type of closure of visceral wall defect, blood loss, complications and length of hospital stay of these studies were evaluated. Additionally all cooperative techniques found were classified and are presented in a systematic approach.

RESULTS

The studies identified were case series and retrospective cohort studies. A total of 706 patients were operated on with a cooperative technique. The tumors resected were only gastrointestinal stromal tumors (GIST) in 4 studies, GIST and various benign submucosal tumors in 22 studies, early gastric cancer (pT1a and pT1b) in 6 studies and early duodenal cancer in 1 study. There was important heterogeneity between the studies. The operative techniques identified were: laparoscopic assisted endoscopic resection, endoscopic assisted wedge resection, endoscopic assisted transgastric and intragastric surgery, laparoscopic endoscopic cooperative surgery (LECS), laparoscopic assisted endoscopic full thickness resection (LAEFR), clean non exposure technique and non-exposed endoscopic wall-inversion surgery (NEWS). Each technique is illustrated with the roles of the endoscopic and laparoscopic teams; the indications, characteristics and short term results are described.

CONCLUSION

Along with the traditional cooperative techniques, new procedures like LECS, LAEFR and NEWS hold great promise for the future of minimally invasive oncologic procedures.

Cutting edge of endoscopic full-thickness resection for gastric tumor

Recently, several studies have reported local full-thickness resection techniques using flexible endoscopy for gastric tumors, such as gastrointestinal stromal tumors, gastric carcinoid tumors, and early gastric cancer (EGC). These techniques have the advantage of allowing precise resection lines to be determined using intraluminal endoscopy. Thus, it is possible to minimize the resection area and subsequent deformity. Some of these methods include: (1) classical laparoscopic and endoscopic cooperative surgery (LECS); (2) inverted LECS; (3) combination of laparoscopic and endoscopic approaches to neoplasia with non-exposure technique; and (4) non-exposed endoscopic wall-inversion surgery. Furthermore, a recent prospective multicenter trial of the sentinel node navigation surgery (SNNS) for EGC has shown acceptable results in terms of sentinel node detection rate and the accuracy of nodal metastasis. Endoscopic full-thickness resection with SNNS is expected to become a treatment option that bridges the gap between endoscopic submucosal dissection and standard surgery for EGC. In the future, the indications for these procedures for gastric tumors could be expanded.

A systematic review and meta-analysis on outcomes after Rx or R1 endoscopic resection of superficial gastric cancer

OBJECTIVE

Endoscopic resection is a standard treatment for gastric superficial lesions. A positive or a nonevaluable margin is considered a noncurative criterion. We aimed to systematically review recurrence, residual disease, lymph node metastasis (LNM) and cancer-related death following Rx/R1 resection of gastric lesions in the absence of other noncurative criteria.

MATERIALS AND METHODS

MEDLINE systematic review and meta-analysis by July 2014.

RESULTS

Data were extracted from 31 manuscripts. Definitions and results differed significantly. However, nonevaluable (HMx) and positive horizontal margins (HM1) were associated with 10% [95% confidence interval (CI) 5-15%] and 36% (95% CI 24-48%) rates of recurrence/residual disease, respectively, with an odds ratio of 2.85 (95% CI 1.6-5.8, P<0.01) for HM1 compared with HMx. Nonevaluable (VMx) or positive (VM1) vertical margin was associated with a 43% (95% CI 17-68%) rate of recurrence/residual. VMx/VM1 was associated with a higher risk of recurrence/residual compared with HMx/HM1 (odds ratio 3.76, 95% CI 1.71-6.82, P<0.01). The most common strategy after HMx/HM1 was endoscopic surveillance and retreatment, whereas surgery was recommended after VMx/VM1. No cases of LNM or cancer-related death were noticeable if neither submucosal invasion more than 500 µm nor lymphovascular infiltration was also reported.

CONCLUSION

Rx/R1 resection in the absence of other noncurative criteria does not appear to be a significant risk factor for LNM or cancer-related death. The risk of recurrence/residual disease is higher after HM1 than HMx and higher after VMx/VM1 than HMx/HM1. However, considerable heterogeneity was found in studies. Standard definitions should be created and applied in future studies.

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

BACKGROUND

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

OBJECTIVE

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

DESIGN/SETTING

Consecutive case series performed by an expertly trained Western endoscopist.

PATIENTS

Fifty-three patients with 54 lesions.

INTERVENTIONS

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

MAIN OUTCOME MEASUREMENTS

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

RESULTS

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

LIMITATION

Long-term outcome data are currently unavailable.

CONCLUSION

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

Optimizing early upper gastrointestinal cancer detection at endoscopy

Survival rates for upper gastrointestinal cancers are poor and oesophageal cancer incidence is increasing. Upper gastrointestinal cancer is also often missed during examinations; a predicament that has not yet been sufficiently addressed. Improvements in the detection of premalignant lesions, early oesophageal and gastric cancers will enable organ-preserving endoscopic therapy, potentially reducing the number of advanced upper gastrointestinal cancers and resulting in improved prognosis. Japan is a world leader in high-quality diagnostic upper gastrointestinal endoscopy and the clinical routine in this country differs substantially from Western practice. In this Perspectives article, we review lessons learnt from Japanese gastroscopy technique, training and screening for risk stratification. We suggest a key performance indicator for upper gastrointestinal endoscopy with a minimum total procedure time of 8 min, and examine how quality assurance concepts in bowel cancer screening in the UK could be applied to upper gastrointestinal endoscopy and improve clinical practice.

Novel strategy of endoscopic submucosal dissection using an insulation-tipped knife for early gastric cancer: near-side approach method

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) using insulation-tipped knives (IT knives) to treat gastric lesions located on the greater curvature of the gastric body remains technically challenging because of the associated bleeding, control of which can be difficult and time consuming. To eliminate these difficulties, we developed a novel strategy which we have called the "near-side approach method" and assessed its utility.

PATIENTS AND METHODS

We reviewed patients who underwent ESD for solitary early gastric cancer located on the greater curvature of the gastric body from January 2003 to September 2014. The technical results of ESD were compared between the group treated with the novel near-side approach method and the group treated with the conventional method.

RESULTS

This study included 238 patients with 238 lesions, 118 of which were removed using the near-side approach method and 120 of which were removed using the conventional method. The median procedure time was 92 minutes for the near-side approach method and 120 minutes for the conventional method. The procedure time was significantly shorter in the near-side approach method arm. Although, the procedure time required by an experienced endoscopist was not significantly different between the two groups (100 vs. 110 minutes), the near-side approach group showed significantly shorter procedure time for a less-experienced endoscopist (90 vs. 120 minutes).

CONCLUSIONS

The near-side approach method appears to require less time to complete gastric ESD than the conventional method using IT knives for technically challenging lesions located on the greater curvature of the gastric body, especially if the procedure is performed by less-experienced endoscopists.

Treatment modalities for early gastric cancer

Different treatment modalities have been proposed in the treatment of early gastric cancer (EGC). Endoscopic resection (ER) is an established treatment that allows curative treatment, in selected cases. In addition, ER allows for an accurate histological staging, which is crucial when deciding on the best treatment option for EGC. Recently, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have become alternatives to surgery in early gastric cancer, mainly in Asian countries. Patients with “standard” criteria can be successfully treated by EMR techniques. Those who meet “expanded” criteria may benefit from treatment by ESD, reducing the need for surgery. Standardized ESD training system is imperative to promulgate effective and safe ESD technique to practices with limited expertise. Although endoscopic resection is an option in patients with EGC, surgical treatment continues to be a widespread therapeutic option worldwide. In this review we tried to point out the treatment modalities for early gastric cancer.

Safety and effectiveness of propofol-based monitored anesthesia care without intubation during endoscopic submucosal dissection for early gastric and esophageal cancers

BACKGROUND AND AIM

Endoscopic submucosal dissection (ESD) becomes more difficult with an increased risk of complications if patient sedation is insufficient. We assessed the safety and effectiveness of propofol-based monitored anesthesia care (MAC) without intubation during ESD for early esophageal cancer (EEC) or early gastric cancer (EGC) in the endoscopy room.

METHODS

We investigated 1013 consecutive patients with 1126 lesions who underwent ESD for EGC/EEC with either MAC or regular sedation by endoscopists (control group) between July 2010 and March 2013. Patient characteristics, endoscopic findings, technical results, body movement, oxygen saturation (SpO2 ), and drug dosages were then examined.

RESULTS

MAC was carried out in 137 EGC (16%) and 82 EEC patients (57%), whereas regular sedation was used in 731 EGC (84%) and 63 EEC patients (43%). MAC was conducted in 21% of all ESD procedures. In the MAC and control groups, body movement requiring a third person for control occurred in 30 (22%) and 533 (72%) cases during gastric ESD (P < 0.0001) and in 36 (44%) and 53 (84%) cases during esophageal ESD (P < 0.0001), respectively. The median minimum SpO2 was significantly lower in the MAC group than in the control group during both gastric and esophageal ESD (96% vs 98%, P < 0.0001; 96% vs 98%, P < 0.0004, respectively). MAC did not cause any adverse effects requiring prolongation of hospitalization.

CONCLUSIONS

Propofol-based MAC without intubation provided a safer treatment environment by significantly reduced body movement and was very effective for difficult cases requiring longer procedure times or more powerful sedation.

Significance of MUC1 expression in biopsy specimens of submucosal invasive gastric carcinoma: The association with lymph node metastasis

Mucin 1, cell surface associated (MUC1) is a tumor-associated glycoprotein that has been reported to have an important role in lymphatic invasion and metastasis. The present study aimed to investigate the significance of MUC1 expression in endoscopic biopsy specimens of submucosal invasive gastric carcinomas and the association with lymph node metastasis. The clinicopathological features of 144 cases of surgically resected submucosal invasive gastric carcinomas and their paired endoscopic biopsy specimens were reviewed. Immunohistochemical staining for MUC1 was performed for the 144 endoscopic biopsy specimens. Positive MUC1 expression was identified in 70 (49%) cases. In addition, univariate analysis revealed that MUC1 expression was significantly associated with the presence of poorly-differentiated (P=0.001) and poorly-cohesive (P=0.015) carcinoma cells, undifferentiated type by Japanese classification (P<0.001), diffuse type of Lauren classification (P<0.001) and lymph node metastasis (P=0.024). By multivariate analysis, diffuse type of Lauren classification (P<0.001) and lymph node metastasis (P=0.035) were identified as independent factors for MUC1 expression. Furthermore, MUC1 expression (P=0.007), tumor size (P=0.018) and lymphatic invasion (P<0.001) were demonstrated to be independent factors for lymph node metastasis under multivariate analysis. In conclusion, the results of the present study indicated that positive MUC1 expression in endoscopic biopsy specimens may be a predictive factor of lymph node metastasis in submucosal invasive gastric carcinoma.

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 undifferentiated-type early gastric cancer: do we have enough data to support this?

Although endoscopic submucosal dissection (ESD) is now accepted for treatment of early gastric cancers (EGC) with negligible risk of lymph node (LN) metastasis, ESD for intramucosal undifferentiated type EGC without ulceration and with diameter ≤ 2 cm is regarded as an investigational treatment according to the Japanese gastric cancer treatment guidelines. This consideration was largely based on the analysis of surgically resected EGCs that contained undifferentiated type EGCs; however, results from several institutes showed some discrepancies in sample size and incidence of LN metastasis. Recently, some reports about the safety and efficacy of ESD for undifferentiated type EGC meeting the expanded criteria have been published. Nonetheless, only limited data are available regarding long-term outcomes of ESD for EGC with undifferentiated histology so far. At the same time, endoscopists cannot ignore the patients' desire to guarantee quality of life after the relatively non-invasive endoscopic treatment when compared to conventional surgery. To satisfy the needs of patients and provide solid evidence to support ESD for undifferentiated EGC, we need more delicate tools to predict undetected LN metastasis and more data that can reveal predictive factors for LN metastasis.

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.

Intramucosal gastric cancer: the rate of lymph node metastasis in signet ring cell carcinoma is as low as that in well-differentiated adenocarcinoma

OBJECTIVE

Endoscopic resection (ER) plays a major role in the management of early gastric cancer. Less lymph node metastasis (LNM) and better survival rates were reported in early gastric signet ring cell carcinoma (SRC) than adenocarcinoma. We investigated and compared the clinicopathologic characteristics of endoscopic and surgical features in early gastric SRC and adenocarcinoma in accordance with histologic differentiation to examine the feasibility of ER in early gastric SRC.

PATIENTS AND METHODS

From January 2003 to September 2011, patients diagnosed with early gastric cancer among patients who had undergone a curative gastrectomy with lymph node dissection were enrolled. Patients' age, sex, tumor size, location, macroscopic type, depth of invasion, lymphovascular invasion (LVI), and LNM were determined.

RESULTS

A total of 696 patients were enrolled. SRC was more frequent in women and more common at the mid-body than differentiated adenocarcinoma. SRC was more common in patients younger than 50 years of age (P < 0.001) and the elevated type was less common in SRC than other adenocarcinomas (P < 0.001). The incidence of submucosal invasion, LVI, and LNM in SRC were similar to well-differentiated adenocarcinoma. Moderately and poorly differentiated group, tumor size greater than 20 mm, submucosal invasion, and LVI were independent risk factors predicting LNM. Intramucosal SRC less than 20 mm had no LNM.

CONCLUSION

Rate of LNM and submucosal invasion in early SRC was as low as those in early well-differentiated adenocarcinoma. ER for early gastric SRC may be an alternative to surgical gastrectomy under certain conditions.

A case of local recurrence and distant metastasis following curative endoscopic submucosal dissection of early gastric cancer

Currently in Japan, differentiated-type gastric submucosal invasive cancers <500 μm with negative lymphovascular involvement are included in expanded pathological criteria for curative endoscopic treatment. This categorization is based on a retrospective examination of surgical resection cases in which patients suitable for such expanded criteria were determined to have a negligible risk of lymph node metastasis. We performed endoscopic submucosal dissection on a 66-year-old man with early gastric cancer in June 2004, and pathology revealed a well-differentiated adenocarcinoma, 16 × 8 mm in size, minute submucosal invasion depth (100 μm), and negative lymphovascular invasion or ulceration as well as tumor-free margins, so the case was diagnosed as a curative resection. In this case, however, local recurrence and distant metastasis resulted in August 2011. The patient received systemic chemotherapy but died of gastric cancer 23 months after recurrence.

Future perspective of gastric cancer endotherapy

Endoscopic resection of early gastric cancer (EGC) has proven safety and efficacy, and is the established standard of care in Japan. In the past decade, it is increasingly established worldwide. The endoscopic submucosal dissection (ESD) is superior to endoscopic mucosal resection (EMR) technique as it is designed to provide adequate staging and long-term curative therapy-based on the en bloc R0 specimen irrespective of the size and/or location of the tumor coupled with the reliable pathological specimen. However, ESD is still requiring skilled and experienced endoscopist to perform because of complex procedures, higher complication and causing long-time consuming. The learning and application of these relatively complex endoscopic techniques for EGC has been shown across the world. Thus, a standardized ESD training system is urgently needed to disseminate safe and effective ESD technique to practices with limited ESD experience. In recent years, several innovations providing solutions to easier and safer performance of ESD have emerged. Those increase control of surgical effectors manipulating the target tissue, and enhance performance in complex surgical tasks. Very recently, the use of the laparoscopic and endoscopic cooperative surgery (LECS) procedure is indicated for EGC that would be difficult to treat with ESD. As an ultimate gastric cancer endotherapy with a reasonable surgical time, LECS might be promising method at this stage. The indications for LECS for EGC could be expanded in the future, which could result in increasingly successful gastric cancer treatment.

Non-curative endoscopic resection does not always lead to grave outcomes in submucosal invasive early gastric cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) has been widely performed for the treatment of early gastric cancer (EGC). The aim of this study is to examine the effectiveness of ESD in submucosal invasive gastric cancers (SM-GC), with a special focus on patients who underwent non-curative resection.

METHODS

Data for 1,246 patients who underwent ESD for treatment of EGC at six medical centers in Daegu-Gyeongbuk, Korea, between February 2003 and May 2010 were collected. After retrospective analysis of ESD databases, 118 patients were enrolled and classified into three groups: (1) EGC with submucosal invasion less than 500 μm (SM1-GC) that met the expanded criteria (EC) (SM1 EC, n = 42); (2) SM1-GC that did not meet the EC (SM1 non-EC, n = 38); and (3) EGC with submucosal invasion greater than 500 μm (SM2-GC, n = 38).

RESULTS

The en bloc and complete resection rates did not differ significantly among the three groups. However, the curative resection rate was significantly better in the SM1 EC group (69.0%) compared to that in SM1 non-EC and SM2-GC groups (0% in both cases). Out of a total of 118 patients, 89 (75.4%) underwent non-curative resection, and cancer recurrence was observed in 9 (9/89, 10.1%). We analyzed the survival rate in these non-curative patients and the overall survival and disease-free survival did not differ significantly between patients that were treated with additional surgical resection and those that were simply followed up after ESD.

CONCLUSIONS

Non-curative resection in SM-GC does not always lead to cancer recurrence. Thus, if additional surgery cannot be performed because of the patient's unsuitable condition or refusal, a close follow-up with endoscopy can be considered as an alternative for carefully selected patients. Moreover, as the ESD technology continues to evolve, it might be possible to expand the criteria for curative ESD in patients with SM-GC.

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.

A new way to experience the International Gastric Cancer Association Congress: the Web Round Tables

In an attempt to attract a wider diversity of professionals to the 10th International Gastric Cancer Association Congress (IGCC) held in June 2013, the Scientific Committee of the conference organized a number of pre-congress Web Round Tables to discuss cutting-edge topics relating to gastric cancer treatment. Twenty Web Round Tables, each coordinated by a different chairman, were proposed on the IGCC Website 1 year before the congress. Each chairman identified a number of studies related to the theme of his/her Round Table and invited corresponding authors to send an update of their conclusions in light of their subsequent experience, which would then form the basis of discussion of the Web Round Tables. The chairmen posted several questions regarding these updates on the web and opened a forum for a period of 1-2 months. The forum was free and specifically intended for congress participants. Fifty-one (9.9 %) of the 516 authors contacted took part in the initiative. Two hundred fifty participants from 21 countries joined the forum discussion and posted 671 comments. The Web Round Tables were viewed 15,810 times while the forum was open. Overall, the Web Round Tables aroused considerable interest, especially among young professionals working in the area of gastric cancer who had the opportunity to contact and interact with experts in what often turned out to be an interesting and lively exchange of views. All the discussions are now freely available for consultation on the IGCC website. The Web Round Table experience was presented, with great success, during the conference at special afternoon sessions.