The modern treatment of early gastric cancer: our experience in an Italian cohort. Surg Endosc. 2009;23:1581-1586. [PMID: 19263148 DOI: 10.1007/s00464-009-0350-5]

American Society for Gastrointestinal Endoscopy guideline on endoscopic submucosal dissection for the management of early esophageal and gastric cancers: methodology and review of evidence

This document from the American Society for Gastrointestinal Endoscopy (ASGE) provides a full description of the methodology used in the review of the evidence used to inform the final guidance outlined in the accompanying Summary and Recommendations document regarding the role of endoscopic submucosal dissection (ESD) in the management of early esophageal and gastric cancers. This guideline used the Grading of Recommendations, Assessment, Development and Evaluation framework and specifically addresses the role of ESD versus EMR and/or surgery, where applicable, for the management of early esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAC), and gastric adenocarcinoma (GAC) and their corresponding precursor lesions. For ESCC, the ASGE suggests ESD over EMR for patients with early-stage, well-differentiated, nonulcerated cancer >15 mm, whereas in patients with similar lesions ≤15 mm, the ASGE suggests either ESD or EMR. The ASGE suggests against surgery for such patients with ESCC, whenever possible. For EAC, the ASGE suggests ESD over EMR for patients with early-stage, well-differentiated, nonulcerated cancer >20 mm, whereas in patients with similar lesions measuring ≤20 mm, the ASGE suggests either ESD or EMR. For GAC, the ASGE suggests ESD over EMR for patients with early-stage, well or moderately differentiated, nonulcerated intestinal type cancer measuring 20 to 30 mm, whereas for patients with similar lesions <20 mm, the ASGE suggests either ESD or EMR. The ASGE suggests against surgery for patients with such lesions measuring ≤30 mm, whereas for lesions that are poorly differentiated, regardless of size, the ASGE suggests surgical evaluation over endosic approaches.

American Society for Gastrointestinal Endoscopy guideline on endoscopic submucosal dissection for the management of early esophageal and gastric cancers: summary and recommendations

This clinical practice guideline from the American Society for Gastrointestinal Endoscopy (ASGE) provides an evidence-based summary and recommendations regarding the role of endoscopic submucosal dissection (ESD) in the management of early esophageal and gastric cancers. It is accompanied by the document subtitled "Methodology and Review of Evidence," which provides a detailed account of the methodology used for the evidence review. This guideline was developed using the Grading of Recommendations, Assessment, Development and Evaluation framework and specifically addresses the role of ESD versus EMR and/or surgery, where applicable, for the management of early esophageal squamous cell carcinoma (ESCC), esophageal adenocarcinoma (EAC), and gastric adenocarcinoma (GAC) and their corresponding precursor lesions. For ESCC, the ASGE suggests ESD over EMR for patients with early-stage, well-differentiated, nonulcerated cancer >15 mm, whereas in patients with similar lesions ≤15 mm, the ASGE suggests either ESD or EMR. The ASGE suggests against surgery for such patients with ESCC, whenever possible. For EAC, the ASGE suggests ESD over EMR for patients with early-stage, well-differentiated, nonulcerated cancer >20 mm, whereas in patients with similar lesions measuring ≤20 mm, the ASGE suggests either ESD or EMR. For GAC, the ASGE suggests ESD over EMR for patients with early-stage, well- or moderately differentiated, nonulcerated intestinal type cancer measuring 20 to 30 mm, whereas for patients with similar lesions <20 mm, the ASGE suggests either ESD or EMR. The ASGE suggests against surgery for patients with such lesions measuring ≤30 mm, whereas for lesions that are poorly differentiated, regardless of size, we suggest surgical evaluation over endoscopic approaches.

Nomogram established using risk factors of early gastric cancer for predicting the lymph node metastasis

BACKGROUND

For the prognosis of patients with early gastric cancer (EGC), lymph node metastasis (LNM) plays a crucial role. A thorough and precise evaluation of the patient for LNM is now required.

AIM

To determine the factors influencing LNM and to construct a prediction model of LNM for EGC patients.

METHODS

Clinical information and pathology data of 2217 EGC patients downloaded from the Surveillance, Epidemiology, and End Results database were collected and analyzed. Based on a 7:3 ratio, 1550 people were categorized into training sets and 667 people were assigned to testing sets, randomly. Based on the factors influencing LNM determined by the training sets, the nomogram was drawn and verified.

RESULTS

Based on multivariate analysis, age at diagnosis, histology type, grade, T-stage, and size were risk factors of LNM for EGC. Besides, nomogram was drawn to predict the risk of LNM for EGC patients. Among the categorical variables, the effect of grade (well, moderate, and poor) was the most significant prognosis factor. For training sets and testing sets, respectively, area under the receiver-operating characteristic curve of nomograms were 0.751 [95% confidence interval (CI): 0.721-0.782] and 0.786 (95%CI: 0.742-0.830). In addition, the calibration curves showed that the prediction model of LNM had good consistency.

CONCLUSION

Age at diagnosis, histology type, grade, T-stage, and tumor size were independent variables for LNM in EGC. Based on the above risk factors, prediction model may offer some guiding implications for the choice of subsequent therapeutic approaches for EGC.

Endoscopic submucosal dissection of gastric neoplastic lesions in Western countries: systematic review and meta-analysis

Endoscopic submucosal dissection (ESD) for gastric neoplastic lesions removal is largely performed in Asian countries. Unfortunately, ESD diffusion, particularly for gastric lesion removal, is still limited in Western countries. We performed a systematic review of available data coming from Western centers. The en bloc and the R0 resection rates for all neoplastic lesions, including early gastric cancer (EGC) and dysplasia, were calculated, as well as the curative rate for EGC. Complications and the 1-month mortality rates were computed. A total of 22 studies from Europe (N = 15), Latina America (N = 6), and Canada (N = 1) were retrieved, with 1152 patients and 1210 lesions. The en bloc resection was successful in 96% [95% confidence interval (CI) 93-98] with a significant heterogeneity (I2 = 63.5%; P < 0.0001). The R0 was achieved in 84% (95% CI 79-89; I2 = 79.9%; P < 0.001). The resection rate was curative in 72% out of 340 patients with EGC (95% CI 65-79, I2 = 8%; P = 0.36). Overall, complications occurred in 9.5% of patients, including bleeding (5.8%), perforation (3.4%), and stenosis (0.35%). A total of three (0.26%) patients deceased within 1 month, but none was directly related to the procedure. Lesion recurrence was observed in 38 (3.5%; 95% CI 2.3-4.4) cases, including 21 EGC and 17 dysplasia. In Western countries, the en bloc and the R0 resections were successful in the large majority of cases, whilst the resection was curative in 72% of patients with EGC. The complications rate was acceptably low.

Machine learning predicts lymph node metastasis of poorly differentiated-type intramucosal gastric cancer

To construct a machine learning algorithm model of lymph node metastasis (LNM) in patients with poorly differentiated-type intramucosal gastric cancer. 1169 patients with postoperative gastric cancer were divided into a training group and a test group at a ratio of 7:3. The model for lymph node metastasis was established with python machine learning. The Gbdt algorithm in the machine learning results finds that number of resected nodes, lymphovascular invasion and tumor size are the primary 3 factors that account for the weight of LNM. Effect of the LNM model of PDC gastric cancer patients in the training group: Among the 7 algorithm models, the highest accuracy rate was that of GBDT (0.955); The AUC values for the 7 algorithms were, from high to low, XGB (0.881), RF (0.802), GBDT (0.798), LR (0.778), XGB + LR (0.739), RF + LR (0.691) and GBDT + LR (0.626). Results of the LNM model of PDC gastric cancer patients in test group : Among the 7 algorithmic models, XGB had the highest accuracy rate (0.952); Among the 7 algorithms, the AUC values, from high to low, were GBDT (0.788), RF (0.765), XGB (0.762), LR (0.750), RF + LR (0.678), GBDT + LR (0.650) and XGB + LR (0.619). Single machine learning algorithm can predict LNM in poorly differentiated-type intramucosal gastric cancer, but fusion algorithm can not improve the effect of machine learning in predicting LNM.

Long-term Results of Endoscopic Submucosal Dissection (ESD) for the Treatment of Early Gastric Cancer (EGC) in a High-volume Latin American Center

BACKGROUND

Gastric cancer is the second leading cause of death by cancer worldwide. Endoscopic submucosal dissection (ESD) is a technique that allows en bloc resection of early lesions of the digestive tract. It has curative potential in selected patients and benefits over gastrectomy for the treatment of early gastric cancer (EGC). The aim of this study is to present the results of ESD for EGC in a high-volume center in Chile.

MATERIALS AND METHODS

Retrospective descriptive study of patients who underwent ESD for EGC at the Doctor Sótero del Río Hospital.

RESULTS

A total of 100 ESDs were performed in 96 patients between 2008 and 2020. Fifty-five percent were female patients, the average age was 68 years (range, 45 to 89 y). En bloc resection was achieved in 98% of cases and the rate of complications Clavien grade III or higher was 8.3%. There were no cases of perioperative mortality. Ninety-three percent of the dissections were classified as R0 and 83% met curative standards according to expanded criteria. The mean follow-up was 42 months (range, 1 to 144 mo). Overall survival was 97%. Cancer-specific survival was 100% and recurrence-free survival was 97%.

CONCLUSIONS

The present study describes the largest series of ESD for the treatment of EGC reported in Latin America. Our results support the feasibility of implementing ESD in Chile and indicate good oncological outcomes comparable to those reported in the large Asian series published to date.

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

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

Endoscopic submucosal dissection versus endoscopic mucosal resection for patients with early gastric cancer: a meta-analysis

OBJECTIVES

To investigate the treatment effects of endoscopic submucosal dissection (ESD) versus endoscopic mucosal resection (EMR) for early gastric cancer (EGC).

DESIGN

Meta-analysis.

METHODS

We systematically searched three electronic databases, including PubMed, EmBase and the Cochrane library for studies published with inception to January 2018. The eligible studies should be evaluated for the efficacy and safety of ESD versus EMR for patients with EGC. The summary ORs and standard mean differences (SMDs) with 95% CIs were employed as effect estimates. Sensitivity analyses were conducted to evaluate the impact of single study on overall analysis. Subgroup analyses were performed for investigated outcomes to evaluate the treatment effects of ESD versus EMR for patients with EGC with specific subsets.

RESULTS

Eighteen studies, with a total of 6723 patients with EGC, were included in final analysis. The summary ORs indicated that patients with EGC who received ESD were associated with an increased incidence of en bloc resection (OR: 9.00; 95% CI: 6.66 to 12.17; p<0.001), complete resection (OR: 8.43; 95% CI: 5.04 to 14.09; p<0.001) and curative resection (OR: 2.92; 95% CI: 1.85 to 4.61; p<0.001) when compared with EMR. Furthermore, ESD was associated with lower risk of local recurrence (OR: 0.18; 95% CI: 0.09 to 0.34; p<0.001). In addition, there was no significant difference between ESD and EMR for the risk of bleeding (OR: 1.26; 95% CI: 0.88 to 1.80; p=0.203). Though, ESD was correlated with greater risk of perforation (OR: 2.55; 95% CI: 1.48 to 4.39; p=0.001), and longer operation time (SMD: 1.12; 95% CI: 0.13 to 2.10; p=0.026) as compared with EMR. Additionally, several different features observed in included studies and patients could bias the effectiveness of ESD versus EMR in patients with EGC.

CONCLUSIONS

ESD is superior than EMR for en bloc resection, complete resection, curative resection and local recurrence, while it increased perforation risk and longer operation time.

Histamine2-Receptor Antagonists, Proton Pump Inhibitors, or Potassium-Competitive Acid Blockers Preventing Delayed Bleeding After Endoscopic Submucosal Dissection: A Meta-Analysis

Background: Endoscopic submucosal dissection (ESD) was commonly used for en bloc resection in gastric cancer and adenoma with the risk of delayed bleeding after ESD. We conducted a direct and indirect comparison meta-analysis to evaluate the best choice in preventing post-ESD bleeding among proton pump inhibitors (PPIs), histamine₂-receptor antagonists (H₂RAs), and the most widely used potassium-competitive acid blocker, vonoprazan.

Methods: The Pubmed, Cochrane Library, and Embase were searched for randomized trials. We pooled odds ratios (OR) for preventing post-ESD bleeding using meta-analysis.

Results: Sixteen randomized trials met the inclusion criteria including 2,062 patients. Direct comparisons showed slightly significant efficacy in PPIs rather than H₂RAs in preventing post-ESD bleeding [OR: 1.83; 95% confidence interval (CI): 1.10 to 3.05] and vonoprazan was better than PPIs (OR: 0.46; 95% CI: 0.25 to 0.86). The adjusted indirect comparison indicated vonoprazan was superior to H₂RAs (OR: 0.30, 95% CI: 0.12 to 0.74). In subgroup analysis, PPIs had similar efficacy as H₂RAs in 4 weeks, while PPIs were better than H₂RAs in 8 weeks’ treatment (OR: 1.91; 95% CI: 1.08 to 3.40). The superiority of vonoprazan than PPIs was more significant in combination therapy (OR: 0.18; 95% CI: 0.04 to 0.69). There was a significant difference in vonoprazan for 8 weeks of medication (OR: 0.44; 95% CI: 0.21 to 0.92).

Conclusions: The effects of vonoprazan is better than PPIs than H₂RAs in preventing bleeding after ESD. When vonoprazan combined with mucosal protective antiulcer drug in treatment or used in 8 weeks of medication, the efficacy may be even better.

How Is Endoscopic Submucosal Dissection for Gastrointestinal Lesions Being Implemented? Results from an International Survey

Background and Study Aim

Superficial gastrointestinal (GI) neoplasms can be treated with endoscopic mucosal resection (EMR) and/or endoscopic submucosal dissection (ESD). These techniques are widely used in Eastern countries; however, its use in the West is limited. The aim of this study was to evaluate the current implementation of ESD in Western countries.

Methods

Western endoscopists (n = 279) who published papers related to EMR/ESD between 2005 and 2017 were asked to complete an online survey from December 2017 to February 2018.

Results

A total of 58 endoscopists (21%) completed the survey. Thirty performed ESD in the esophagus (52%), 45 in the stomach (78%), 36 in the co-lorectum (62%), and 6 in the duodenum (10%). The median total number of lesions ever treated per endoscopist was 190, with a median number per endoscopist in 2016 of 41 (7 [IQR 1-21], 6 [IQR 4-16], and 28 [5-63] in the esophagus, in the stomach, and in the colon and rectum, respectively). En bloc resection rates were 97% in the esophagus, 95% in the stomach, and 84% in the colorectum. Complete resection (R0) was achieved in 88, 91, and 81%, respectively. Curative rates were 69, 70, and 67%, respectively. Major complications (perforation or delayed bleeding) occurred more often in colorectal ESD (12 vs. 6% in the esophagus and 7% in the stomach). In the upper GI tract, the majority of resected lesions were intramucosal adenocarcinoma (59% in the esophagus; 47% in the stomach), while in the colorectum the majority were adenomas (59%).

Conclusion

ESD seems to be performed by a large number of centers and endoscopists. Our results suggest that ESD is being successfully implemented in Western countries, achieving a good rate of efficacy and safety according to European guidelines.

Introduction of endoscopic submucosal dissection in the West

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

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

BACKGROUND

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

METHODS

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

RESULT

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

CONCLUSION

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

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

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

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

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

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

Efficacy of endoscopic mucosal resections for the management of small gastric adenomas with low-grade dysplasia

OBJECTIVE

Gastric adenoma with low-grade dysplasia (LGD) can progress to gastric cancer; however, the optimal therapeutic modality for LGD has not been established. The aim of this study was to assess the efficacy, safety of and local recurrence following endoscopic mucosal resection (EMR) for LGD. Specifically, we compared EMR with circumferential precutting (EMR-P) and EMR using a dual-channel endoscope (EMR-D) for the treatment of LGD ≤2 cm.

MATERIALS AND METHODS

A total of 158 lesions from 147 patients with LGD treated by EMR were retrospectively analyzed. The en bloc resection rate, complete resection rate, procedure time, complication rate and local recurrence rate were compared between EMR-P and EMR-D.

RESULTS

The en bloc resection and complete resection rates of EMR were 91.1% and 90.5%, respectively. The bleeding and perforation rates were 1.3% and 1.3%, respectively. The local recurrence rate following EMR was 2.2%. The en bloc resection and complete resection rates did not differ between EMR-P and EMR-D (88.2% vs. 92.5%, p = not significant (NS); and 90.2% vs. 90.7%, p = NS, respectively). The procedure time was significantly longer for EMR-P compared with EMR-D (16 (5-141) vs. 7 (2-48) min, p < 0.001), and the complication rate was significantly higher for EMR-P (7.8% vs. 0.0%, p = 0.010). Local recurrence was not found in EMR-P, whereas the recurrence rate was 3.2% in EMR-D.

CONCLUSION

EMR is an effective method for the treatment of LGD ≤2 cm. Compared with EMR-P, EMR-D appears to be the more effective, technically simple and safer method.

How to establish endoscopic submucosal dissection in Western countries

Endoscopic submucosal dissection (ESD) has been invented in Japan to provide resection for cure of early cancer in the gastrointestinal tract. Professional level of ESD requires excellent staging of early neoplasias with image enhanced endoscopy (IEE) to make correct indications for ESD, and high skills in endoscopic electrosurgical dissection. In Japan, endodiagnostic and endosurgical excellence spread through personal tutoring of skilled endoscopists by the inventors and experts in IEE and ESD. To translocate this expertise to other continents must overcome two fundamental obstacles: (1) inadequate expectations as to the complexity of IEE and ESD; and (2) lack of suitable lesions and master-mentors for ESD trainees. Leading endoscopic mucosal resection-proficient endoscopists must pioneer themselves through the long learning curve to proficient ESD experts. Major referral centers for ESD must arise in Western countries on comparable professional level as in Japan. In the second stage, the upcoming Western experts must commit themselves to teach skilled endoscopists from other referral centers, in order to spread ESD in Western countries. Respect for patients with early gastrointestinal cancer asks for best efforts to learn endoscopic categorization of early neoplasias and skills for ESD based on sustained cooperation with the masters in Japan. The strategy is discussed here.

Endoscopic mucosal resection

EMR has become an established therapeutic option for premalignant and early-stage GI malignancies, particularly in the esophagus and colon. EMR can also aid in the diagnosis and therapy of subepithelial lesions localized to the muscularis mucosa or submucosa. Several dedicated EMR devices are available to facilitate these procedures. Adverse event rates, particularly bleeding and perforation, are higher after EMR relative to other basic endoscopic interventions but lower than adverse event rates for ESD. Endoscopists performing EMR should be knowledgeable and skilled in managing potential adverse events resulting from EMR.

Multimodal treatment of gastric cancer in the west: Where are we going?

The incidence of gastric cancer (GC) is decreasing worldwide, especially for intestinal histotype of the distal third of the stomach. On the contrary, proximal location and diffuse Lauren histotype have been reported to be generally stable over time. In the west, no clear improvement in long-term results was observed in clinical and population-based studies. Results of treatment in these neoplasms are strictly dependent on tumor stage. Adequate surgery and extended lymphadenectomy are associated with good long-term outcome in early-stage cancer; however, results are still unsatisfactory for advanced stages (III and IV), for which additional treatments could provide a survival benefit. This implies a tailored approach to GC. The aim of this review was to summarize the main multimodal treatment options in advanced resectable GC. Perioperative or postoperative treatments, including chemotherapy, chemoradiotherapy, targeted therapies, and hyperthermic intraperitoneal chemotherapy have been reviewed, and the main ongoing and completed trials have been analyzed. An original tailored multimodal approach to non-cardia GC has been also proposed.

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.

Subtotal gastrectomy for gastric cancer

Although a steady decline in the incidence and mortality rates of gastric carcinoma has been observed in the last century worldwide, the absolute number of new cases/year is increasing because of the aging of the population. So far, surgical resection with curative intent has been the only treatment providing hope for cure; therefore, gastric cancer surgery has become a specialized field in digestive surgery. Gastrectomy with lymph node (LN) dissection for cancer patients remains a challenging procedure which requires skilled, well-trained surgeons who are very familiar with the fast-evolving oncological principles of gastric cancer surgery. As a matter of fact, the extent of gastric resection and LN dissection depends on the size of the disease and gastric cancer surgery has become a patient and “disease-tailored” surgery, ranging from endoscopic resection to laparoscopic assisted gastrectomy and conventional extended multivisceral resections. LN metastases are the most important prognostic factor in patients that undergo curative resection. LN dissection remains the most challenging part of the operation due to the location of LN stations around major retroperitoneal vessels and adjacent organs, which are not routinely included in the resected specimen and need to be preserved in order to avoid dangerous intra- and postoperative complications. Hence, the surgeon is the most important non-TMN prognostic factor in gastric cancer. Subtotal gastrectomy is the treatment of choice for middle and distal-third gastric cancer as it provides similar survival rates and better functional outcome compared to total gastrectomy, especially in early-stage disease with favorable prognosis. Nonetheless, the resection range for middle-third gastric cancer cases and the extent of LN dissection at early stages remains controversial. Due to the necessity of a more extended procedure at advanced stages and the trend for more conservative treatments in early gastric cancer, the indication for conventional subtotal gastrectomy depends on multiple variables. This review aims to clarify and define the actual landmarks of this procedure and the role it plays compared to the whole range of new and old treatment methods.

Ever-changing endoscopic treatment for early gastric cancer: Yesterday-today-tomorrow

Endoscopic resection has been an optimal treatment for selected patients with early gastric cancer (EGC) based on advances in endoscopic instruments and techniques. As endoscopic submucosal dissection (ESD) has been widely used for treatment of EGC along with expanding ESD indication, concerns have been asked to achieve curative resection for EGC while guaranteeing precise prediction of lymph node metastasis (LNM). Recently, new techniques including ESD or endoscopic full-thickness resection combined with sentinel node navigation enable minimal tumor resection and a laparoscopic lymphadenectomy in cases of EGC with high risk of LNM. This review covers the development and challenges of endoscopic treatment for EGC. Moreover, a new microscopic imaging and endoscopic techniques for precise endoscopic diagnosis and minimally invasive treatment of EGC are introduced.

Treatment of early gastric cancer in the Western World

The incidence rate of gastric cancer is much higher in Asia than in the Western industrial nations. According to the different screening programs in Japan and Korea about fifty percent of treated patients had an early tumor stage. In contrast, European and American patients with gastric cancer had an advanced tumor stage. Therefore, the experience for the various therapeutic options for gastric cancer may be different between these regions. In this review we tried to point out the treatment modalities in Western industrial countries for early gastric cancer.

A double-blind, block-randomized, placebo-controlled trial to identify the chemical assistance effect of mesna submucosal injection for gastric endoscopic submucosal dissection

BACKGROUND

Previous animal studies and a pilot clinical trial demonstrated that submucosal injection of a thiol compound called mesna could chemically soften connective tissues and thus facilitate endoscopic submucosal dissection (ESD).

OBJECTIVE

To evaluate whether mesna injection could reduce procedural times for gastric ESD.

DESIGN

Double-blind, block-randomized, controlled trial.

SETTING

University hospital.

PATIENTS

A total of 101 patients with superficial gastric cancer indicated for ESD were enrolled and randomly assigned to either the mesna or control (saline solution) group.

INTERVENTION

Traditional ESD was performed with a single bolus injection of mesna or saline solution.

MAIN OUTCOME MEASUREMENTS

Time for submucosal dissection (TSD).

RESULTS

En bloc resection was achieved for all lesions in the mesna group (53/53) and 51 of 52 lesions (98.08%) in the control group. TSD was not statistically different between the groups (18.62 ± 13.9 [mean ± SD] minutes for the mesna group and 24.58 ± 24.55 [mean ± SD] minutes for the control group; P = .128), and there were fewer time-consuming cases (times over 30 minutes) in the mesna group compared with controls (7/53 vs 15/52; P = .049). Multivariate regression analysis demonstrated that use of mesna, specimen size, and the presence of fibrous scars were significantly correlated with TSD (P < .05).

LIMITATIONS

Single-center study.

CONCLUSION

TSD was not significantly different between the mesna and control injection groups, but multivariate analysis indicated that mesna injection reduced procedural challenges associated with the submucosal dissection. (

CLINICAL TRIAL REGISTRATION NUMBER

UMIN000003786.).

ESD around the world: Europe

In Europe, endoscopic mucosal resection (EMR) is widely accepted as an appropriate diagnostic approach to obtain specimens for accurate histopathologic evaluation, which may change grading and local staging of early neoplasia determined by prior biopsies and imaging. In contrast to EMR, endoscopic submucosal dissection (ESD) allows resection of even large lesions in a single piece. Evidence on the clinical value of ESD is still limited and mainly based on data from Japan, and may not be directly applicable to Europe, where the outcome of ESD may be less favorable because of the limited Western expertise in this challenging technique.

Gastric ESD: current status and future directions of devices and training

Endoscopic mucosal resection (EMR) of early gastric cancer, which has been proved to be safe and effective and is the established standard of care in Japan, has become increasingly established worldwide in the past decade. Endoscopic submucosal dissection (ESD) is superior to EMR, as it is designed to provide precise pathologic staging and long-term curative therapy based on an en bloc R0 specimen irrespective of the size and/or location of the tumor. However, ESD requires highly skilled and experienced endoscopists. The introduction of ESD to the Western world necessitates collaborations between Eastern and Western endoscopists, pathologists, and surgeons.

An electrosurgical endoknife with a water-jet function (flushknife) proves its merits in colorectal endoscopic submucosal dissection especially for the cases which should be removed en bloc

Background. Previously, we reported that the Flushknife (electrosurgical endoknife with a water-jet function) could reduce the operation time of colorectal endoscopic submucosal dissection (ESD) however, suitable situation for the Flushknife was obscure. This subgroup analysis of a prospective randomized controlled trial was aimed to investigate the suitable situation for the Flushknife. Methods. A total of 48 superficial colorectal neoplasms that underwent ESD using either the Flexknife or the Flushknife in a referral center were enrolled. The differences of operation time between the Flexknife and the Flushknife groups in each subgroup (tumor size, location, and macroscopic type) were analyzed. Results. Median (95% CI) operation time calculated using survival curves was significantly shorter in the Flushknife group than in the Flexknife group (55.5 min [41, 78] versus 74.0 [57, 90] min; P = 0.039, Hazard Ratio HR: 0.53; 95% CI (0.29-0.97)). In particular, the HR in patients with laterally spreading tumors-nongranular type (LST-NG) in the Flushknife group was significantly smaller than in the Flexknife group (HR: 0.165→0.17; 95% CI (0.04-0.66)). There was a trend of decreasing HRs according to larger lesion size. Conclusions. The Flushknife proved its merits in colorectal ESD especially for the lesions which should be removed en bloc (LST-NG and large lesion).

Antithrombotic drugs are risk factors for delayed postoperative bleeding after endoscopic submucosal dissection for gastric neoplasms

BACKGROUND

The discontinuation of antithrombotic drugs is recommended during endoscopic submucosal dissection (ESD) for gastric neoplasms; however, controversy remains as to whether antithrombotic drugs are risk factors for postoperative bleeding.

OBJECTIVE

To determine the risk factors for post-ESD bleeding.

DESIGN

Single-institution, retrospective review.

SETTING

University hospital.

PATIENTS

From June 2000 to December 2010, we treated 1192 gastric neoplasms in 1032 consecutive patients.

INTERVENTION

The ESD procedures were performed by using the standard techniques. Antithrombotic drug therapy was principally interrupted preoperatively and was restarted when hemostasis was confirmed by second-look endoscopy.

MAIN OUTCOME MEASUREMENTS

Risk factors for postoperative bleeding after ESD (early, delayed, and overall [combined] occurrence of bleeding during the first 5 postoperative days or thereafter) were analyzed by using logistic regression analysis.

RESULTS

Among 1166 ESD-induced ulcer lesions, overall postoperative bleeding was evident in 62 lesions (5.3%); early and delayed bleeding occurred in 30 and 32 lesions (2.6% and 2.7%), respectively. Based on a multivariate analysis, a specimen size of >40 mm was the sole independent risk factor for overall bleeding. Moreover, oral antithrombotic drug therapy was selected as independent risk factor for delayed but not early bleeding, according to the multivariate analysis. The delayed bleeding rate in patients who had a specimen size of >40 mm and who used antithrombotic drugs was 11.6%.

LIMITATIONS

Retrospective design and single-site data collection.

CONCLUSION

Interruption of antithrombotic drug therapy may be adequate for preventing early post-ESD bleeding; however, reinitiating antithrombotic drug therapy is a significant independent risk factor for delayed post-ESD bleeding.

Endoscopic resection (endoscopic mucosal resection/ endoscopic submucosal dissection) for early gastric cancer

Endoscopic resection of early gastric cancer is a well-established standard therapy in Japan and Korea, and is increasingly used in other countries. Endoscopic resection should be curative for patients, and safe, easy and effective not only for patients, but also for endoscopists. Endoscopic submucosal dissection (ESD) is superior to standard endoscopic mucosal resection (EMR) as it is designed to provide en bloc R0 resection regardless of size and/or location. Correct pathological assessment of en bloc resected specimens is crucial for accurate diagnosis and patient stratification for the risk of metastasis. Outcome studies in Japan and Korea, countries with the highest incidence of gastric cancer, have shown that ESD is efficacious in leading to a good long-term outcome; however, ESD requires an experienced endoscopist with a high skill level. Expanded indications for endoscopic resection have been proposed, especially after large en bloc resection have been accomplished using ESD. The use of ESD could be of huge benefit for the management of gastrointestinal superficial neoplasms. However, for ESD to become a viable therapeutic option, it requires close and supportive working relationships between endoscopists, pathologists and surgeons.

The current state of diagnosis and treatment for early gastric cancer

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

A meta-analysis of endoscopic submucosal dissection and EMR for early gastric cancer

BACKGROUND

Endoscopic submucosal dissection (ESD) was developed to overcome the problem caused by incomplete resection by conventional EMR for early gastric cancer. However, the technique of ESD had a relative higher incidence rate of complications such as bleeding and perforation because of its large wound incidence and difficulties.

OBJECTIVE

To evaluate the efficacy and safety of ESD and EMR for early gastric cancer.

DESIGN

We made an overall strategy to search various databases both electronically and manually and assessed the quality of selected articles according to the inclusion and exclusion standard.

SETTING

Meta-analysis of 9 retrospective studies.

PATIENTS

3548 lesions (ESD 1495; EMR 2053).

INTERVENTION

ESD or EMR.

MAIN OUTCOME MEASUREMENTS

En bloc resection rate, histologic curative resection rate, complications, recurrence rate.

RESULTS

Nine retrospective studies were identified (7 full text and 2 abstracts). A total of 3548 lesions were enrolled (ESD 1495; EMR 2053). The mean time required for resection was longer for ESD than for EMR (weighted mean difference 59.4; 95% confidence interval [CI], 16.8-102.0); the en bloc rate in the ESD group was significantly higher than that in the EMR group (OR 9.69; 95% CI, 7.74-12.13), and so was the total histologically complete resection rate (OR 5.66; 95% CI, 2.92-10.96). The ESD group had lower recurrence frequency (OR 0.10; 95% CI, 0.06-0.18). The perforation rate was higher in the ESD group (OR 4.67; 95% CI, 2.77-7.87), whereas the bleeding incidences were similar between the two groups.

LIMITATIONS

Heterogeneity was present among the studies.

CONCLUSION

Compared with EMR for early gastric cancer, ESD showed considerable advantages regarding en bloc resection rate, histologically complete resection rate, and local recurrence even for small lesions, but it had the disadvantages of higher complication rates for perforation. All of the results mentioned should be confirmed by well-designed, randomized, controlled trials from more countries, with larger samples and long enough follow-up periods.

Endoscopic submucosal dissection--current success and future directions

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

Determining early gastric cancer lesions appropriate for endoscopic submucosal dissection trainees: a proposal related to curability

Endoscopic submucosal dissection (ESD) was introduced worldwide as a new treatment option for early gastric cancer. Our objective was to discuss the limited ESD reports available and to determine the lesions suitable for use in training endoscopists on which lesions are appropriate for ESD. We reviewed a series of ESD reports that have been written on various risk factors related to the resectability or curability of a variety of lesions. These published studies show that certain risk factors such as tumor size and location and the presence of ulceration are closely related to both resectability and curability. Because the combination of these risk factors resulted in a much higher risk than did any single factor, we recently established a 'risk assessment chart' to determine an individual's total risk of treatment failure for early gastric cancer that has been treated using ESD. This risk chart provides a clear indication that small, non-ulcerated lesions located in the lower third of the stomach have a high rate of curative resection and are technically less challenging if ESD is used. We suggest that trainees should gain ESD experience with such lesions before they start to perform ESD on more difficult lesion types that have a lower probability of curative resection. In addition, we suggest that this risk assessment chart is suitable for the pretreatment assessment of curability and the likelihood of successful en bloc resection.

[Endoscopic submucosal dissection: only for expert endoscopists?]

Endoscopic submucosal dissection (ESD) can be applied to early gastrointestinal cancers. This technique was developed to achieve radical curative resection and to reduce unnecessary surgical interventions. ESD was designed in eastern countries and is not widely used in the West. Although ESD represents a major therapeutic advance in endoscopy and is performed with curative intent, the complication rate (hemorrhage, perforation) is higher than reported in other techniques, requiring from endoscopists the acquirement of technical skill and experience through a structured and progressive training program to reduce the morbidity associated with this technique and increase its potential benefits. Although there is substantial published evidence on the applications and results of ESD, there are few publications on training in this technique and a standardized training program is lacking. The current article aims to describe the various proposals for training, as well as the basic principles of the technique, its indications, and the results obtained, since theoretical knowledge that would guide endoscopists during the clinical application of ESD is advisable before training begins. Training in an endoscopic technique has a little value without knowledge of the technique's aims, the situations in which it should be applied, and the results that can be expected.

Risk assessment chart for curability of early gastric cancer with endoscopic submucosal dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) was introduced worldwide as a new treatment option for early gastric cancer, but curability prediction has not been evaluated on an individual basis.

OBJECTIVE

To analyze factors contributing to the curability of early gastric cancer after ESD and to construct a risk assessment chart for the probability of curability.

DESIGN

Single-institution retrospective review.

SETTING

University hospital.

PATIENTS

From June 2000 to April 2010, we treated 961 early gastric cancers in 784 patients (mean age 70.2 years).

INTERVENTION

ESD procedures were performed using typical sequences.

MAIN OUTCOME MEASUREMENTS

Risk factors related to resectability (en bloc or piecemeal resection) and curability (curative or noncurative resection) after ESD were analyzed using logistic regression analysis. Using this model, we constructed a risk assessment chart to predict the probability of noncurability from patient characteristics.

RESULTS

The en bloc and curative resection rates were 98.9% and 88.1%, respectively, after ESD. Significant contributors to noncurative ESD were large lesions, upper location, and ulcer findings. Predicted noncurability probabilities were displayed in 4 colors for each risk level (light blue, blue, yellow, and red) by combining tumor size, tumor location, and ulcer findings. Probability of noncurability was highest (≥ 40%) in ulcerative large tumors (>30 mm in diameter) in the upper location (red) and lowest in nonulcerative small tumors (≤ 20 mm in diameter) in the lower location (light blue).

LIMITATIONS

Retrospective design and single-site data collection.

CONCLUSIONS

This risk assessment chart shows individuals their pretreatment curability assessment with successful ESD and may be an educational tool for trainees or a decision-making tool.

Worldwide experiences of endoscopic submucosal dissection: Not just Eastern acrobatics

The high incidence of gastric cancer has led to the initiation of cancer screening programs. As a result, the number of early gastric cancer cases has increased and consequentially, the cancer mortality rate has decreased. Moreover, the development of minimally invasive endoscopic treatment has been introduced for these early lesions. Endoscopic submucosal dissection (ESD) is now recognized as one of the preferred treatment modalities for premalignant gastrointestinal epithelial lesions and early gastric cancer without lymph node metastasis. We review the results of ESD including experiences in Japan and Korea, as well as western countries.

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) in 2011, a Western perspective

Endoscopic mucosal resection (EMR) has become the standard of care for removal of large flat and sessile neoplastic lesions of the GI tract. Recently, endoscopic submucosal dissection (ESD) was introduced in Japan as an alternative technique, which allows en bloc resection of large lesions. The applications of EMR and ESD are expanding and many Western endoscopists are adopting these techniques. Paris classification and Kudo pit pattern classification allows prediction of the depth of invasion of early neoplastic lesions and thus, avoids resection of lesions invading the deep submucosa which have higher rates of lymphatic spread. ESD of early stomach cancer is the standard of care in Japan. Recent published reports from Western countries showed comparable results for ESD of early gastric cancers to those done in Japan. Recently, EMR combined with ablation has been used frequently in Western countries for treatment of high-grade dysplasia in early adenocarcinoma of the esophagus. Although ESD of early neoplastic lesions of the esophagus is technically difficult, few promising reports were published proving the feasibility of this technique in the West. ESD has been shown to achieve higher en bloc resection and lower rates of tumour recurrence in removal of lateral spreading colonic polyps. A hybrid technique of circumferential submucosal incision followed by en bloc EMR has been used for removal of large colonic lesions in some Western endoscopy centres. In Western countries, training for ESD is challenging given the lack of training in the relatively easier early gastric cancer lesions. Animal model training combined with observing experts in ESD could be an alternative for Western endoscopists. Inspite of obstacles, ESD applications are continuing to grow in Western countries.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Three-dimensional MDCT for preoperative local staging of gastric cancer using gas and water distention methods: a retrospective cohort study

OBJECTIVE

The purpose of this article is to compare the T-staging accuracy and lesion detectability of MDCT with gas distention versus water distention according to the surgical and histopathologic findings, for the preoperative evaluation of gastric cancer.

MATERIALS AND METHODS

For a 3-month period, 113 consecutive patients (72 men and 41 women; age range, 23-85 years; mean age, 58 years) with 116 surgically confirmed gastric cancers from a single institution were included in our study. All patients had undergone preoperative MDCT with either effervescent granules taken orally (n = 55) or after having drunk 1,000 mL of tap water (n = 58) to create gastric distention. In addition to transverse images, multiplanar reformation images and 3D surface shaded display images were also obtained with gas distention CT, and multiplanar reformation images were obtained with water distention CT. The CT images were retrospectively reviewed by two abdominal radiologists separately with regard to T staging and lesion detectability. The accuracy values were compared between the two methods using Fisher's exact test.

RESULTS

The T-staging accuracy for gastric cancer did not differ significantly between gas distention and water distention CT scans, according to both radiologists (p > 0.05). Furthermore, the staging accuracy values for T1a cancers on gas distention CT scans for radiologists 1 and 2 were also comparable with those of water distention CT scans (91.1% vs 85% for radiologist 1 and 89.3% vs 85% for radiologist 2; p > 0.05). However, the tumor detection rate was significantly higher on gas distention CT scans using 2D and surface shaded display images for both radiologists (94.6% for radiologist 1 and 91.1% for radiologist 2), compared with the rates for water distention CT scans (78.3% and 73.3%) or gas distention CT scans using only 2D images (75.0% and 67.9%) (p < 0.05).

CONCLUSION

MDCT using the gas distention technique showed performance comparable to that of the water distention technique for the T staging of preoperative gastric cancer with better lesion detectability.

A Western single-center experience with endoscopic submucosal dissection for early gastrointestinal cancers

Endoscopic submucosal dissection (ESD) has gained worldwide acceptance as a treatment for early gastrointestinal cancers (EGICs). However, the management of these tumors in the Western world is still mainly surgical. Our aim was to evaluate the safety and feasibility of ESD at a European center. Based on the knowledge transferred by one of the most experienced Japanese institutions, we conducted a pilot study on 25 consecutive patients with EGICs located in the esophagus (n = 3), stomach (n = 7), duodenum (n = 1), and colon (n = 14) at our tertiary center over a 2-year-period. The main outcome measurements were complete (R0) resection, as well as en-bloc resection and the management of complications. The R0 and en-bloc resection rates were 100% and 84%, respectively. There were three cases of bleeding and five cases of perforation. With a median follow up of 18 months, two recurrences were observed. We conclude that ESD for early esophageal and gastric cancers is feasible and effective, while colonic ESD requires more expertise.