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

Risk factors of lymph node metastasis in 1620 early gastric carcinoma radical resections in Jiangsu Province in China: A multicenter clinicopathological study

OBJECTIVE

To investigate risk factors of lymph node metastasis (LNM) in early gastric carcinoma (EGC) in four tertiary medical centers in Jiangsu Province, China.

METHODS

Among 10 097 consecutive combined gastric cancer radical resections, 1903 EGC were identified and reviewed, 283 excluded and 1620 included in the study. All pathological and some endoscopic reports were reviewed for patients' characteristics, tumor location, gross features, and the number of lymph nodes retrieved and involved. Two pathologists independently investigated the pathological features of tumor type, differentiation, invasion depth, lymphovascular invasion (LVI), and perineural invasion. The data were statistically analyzed to identify risk factors for LNM.

RESULTS

The average number of lymph nodes retrieved was 17.5 per patient. LNM was diagnosed in 15.5%. By univariate analysis, significant risk factors for LNM included age ≥ 41 years, female sex, size over 1 cm, submucosal invasion, poor differentiation, poorly cohesive carcinoma, micropapillary adenocarcinoma, adenocarcinoma mixed with signet-ring cell carcinoma, LVI, perineural invasion, and distal gastric location. By multivariate analysis, independent risk factors for LNM were size ≥ 3 cm (odds ratio [OR] 1.9), poor differentiation (OR 2.5), adenocarcinoma mixed with signet-ring cell carcinoma (OR 1.7), LVI (OR 5.8) and submucosal invasion (OR 2.9). In contrast, size < 3 cm and ulcer were not significant risk factors. Early cardiac carcinoma (OR 0.4) had significantly lower risk.

CONCLUSIONS

Independent risk factors for LNM in EGC in Chinese patients included tumor size ≥ 3 cm, poor differentiation, submucosal invasion, adenocarcinoma mixed with signet-ring cell carcinoma and LVI. Early cardiac carcinoma had a significantly lower risk for LNM.

Comparison of DWI and 18F-FDG PET/CT for assessing preoperative N-staging in gastric cancer: evidence from a meta-analysis

The diagnostic values of diffusion weighted imaging (DWI) and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) for N-staging of gastric cancer (GC) were identified and compared. After a systematic search to identify relevant articles, meta-analysis was used to summarize the sensitivities, specificities, and areas under curves (AUCs) for DWI and PET/CT. To better understand the diagnostic utility of DWI and PET/CT for N-staging, the performance of multi-detector computed tomography (MDCT) was used as a reference. Fifteen studies were analyzed. The pooled sensitivity, specificity, and AUC with 95% confidence intervals of DWI were 0.79 (0.73–0.85), 0.69 (0.61–0.77), and 0.81 (0.77–0.84), respectively. For PET/CT, the corresponding values were 0.52 (0.39–0.64), 0.88 (0.61–0.97), and 0.66 (0.62–0.70), respectively. Comparison of the two techniques revealed DWI had higher sensitivity and AUC, but no difference in specificity. DWI exhibited higher sensitivity but lower specificity than MDCT, and ¹⁸F-FDG PET/CT had lower sensitivity and equivalent specificity. Overall, DWI performed better than ¹⁸F-FDG PET/CT for preoperative N-staging in GC. When the efficacy of MDCT was taken as a reference, DWI represented a complementary imaging technique, while ¹⁸F-FDG PET/CT had limited utility for preoperative N-staging.

Metachronous Gastric Cancer Following Curative Endoscopic Resection of Early Gastric Cancer

This review article summarizes knowledge about metachronous gastric cancer (MGC) occurring after curative endoscopic resection (ER) of early gastric cancer (EGC), treatment outcomes of patients who developed MGC, and efficacy of Helicobacter pylori eradication to prevent MGC. The incidence of MGC following curative ER increases over time and is higher than in patients undergoing gastrectomy. Increasing age and multifocal EGC are independent risk factors for developing MGC. An MGC following curative ER is usually a small (<20 mm) and differentiated intramucosal cancer. Most MGC lesions are found at an early stage on semiannual or annual surveillance endoscopy and are successfully treated by further ER, with excellent long-term outcomes. Eradication of H. pylori may reduce the risk of MGC following ER of EGC, but further prospective studies with long-term outcomes are required. Surveillance endoscopy following gastric ER should be continued indefinitely, due to the risk of MGC even after successful H. pylori eradication. Risk stratification and tailored endoscopic surveillance schedules need to be developed.

Standard needle versus needleless injection modality: animal study on different fluids for submucosal elevation

BACKGROUND AND AIMS

Submucosal injection is currently used in GI endoscopy to reduce resection risks and to perform submucosal dissection; it is usually performed via an injection needle or a needleless device. The aim of the study was to compare 2 submucosal injection modalities (needle-assisted vs needleless) by using substances with different viscosities.

METHODS

Needle and needleless injections were compared by assessing the efficacy of tissue elevation with 5 different substances in an ex vivo porcine model. The height of the submucosal elevation was measured 0(t0), 10(t1), and 30 minutes after injection (t2). Viscosity of the solution was also measured.

RESULTS

For both stomach and rectum, at t0, t1, and t2 no difference in the height of the elevation was found between the needle and needleless technique, irrespective of the substance. Tissue elevation in the stomach was similar between the 2 techniques at t0 (9.9 ± 1.58 vs 9.4 ± 1.3 mm, P = .3), t1 (7.2 ± 1.56 vs 6.9 ± 1.4 mm, P =. 26), and t2 (6 ± 1.6 vs 5.5 ± 1.3 mm, P = .18). No difference was found in the rectum at t1 and t2, whereas a slightly higher elevation with the needle-assisted technique was observed at t0 (t0: 12.4 ± 1.3 vs 11.2 ± 1.6 mm, P = .003; t1: 8.7 ± 1.3 vs 8.3 ± 1.5 mm; P = .32; t2: 7.0 ± 1.4 vs 7.2 ± .76 mm; P = .75). When comparing the substances with normal saline solution, more viscous solutions showed a significantly higher elevation at t0, t1, and t2 irrespective of the injection modalities and the location.

CONCLUSIONS

No differences were found in the height of submucosal injection or in the persistence of such elevation when comparing needleless with needle-assisted injection, with the only minor exception of the initial elevation in the rectum, which does not appear to be clinically relevant. Viscous solutions resulted in higher and more persistent elevations as compared with normal saline solution.

Long-term outcomes of patients with early gastric cancer found to have lesions for which endoscopic treatment is not indicated on histopathological evaluation after endoscopic submucosal dissection

BACKGROUND

Gastric cancer treatment guidelines recommend additional surgery as the standard treatment for lesions for which endoscopic submucosal dissection (ESD) is not indicated. However, the incidence of lymph-node metastasis is low in most patients.

METHODS AND MATERIALS

The study comprised 231 patients (231 lesions) who underwent ESD for early gastric cancer (EGC) in our hospital from September 2002 through March 2015 and were found to have lesions for which endoscopic treatment is not indicated on histopathological evaluation after ESD. The patients were divided into the additional operation group and the follow-up group, and long-term outcomes were studied retrospectively. Risk factors for metastasis and recurrence were also studied (capture rate, 98.7%).

RESULTS

The median follow-up was 48 months. There were 174 men and 57 women with a median age of 72 years. The additional operation group comprised 118 patients, and the follow-up group comprised 113 patients. The rates of 5-year cause-specific survival and 5-year overall survival were significantly higher in the additional operation group (100 and 96.0%, respectively) than in the follow-up group (92.6 and 73.3%, respectively; p = 0.010, p < 0.001). In the follow-up group, 5 patients (4.4%) died of gastric cancer (p = 0.021). Among elderly patients 75 years or older, long-term outcomes did not differ significantly between the groups. Sixteen patients had metastasis or recurrence, and the presence of lymphatic involvement was an independent risk factor for metastasis, recurrence, or both (p = 0.003; odds ratio 10.594; 95% confidence interval 2.294-48.927).

CONCLUSIONS

In patients with EGC who are confirmed to have lesions for which endoscopic treatment is not indicated on histopathological evaluation after ESD, additional surgery should be aggressively performed if the patient can tolerate such treatment. In elderly patients aged 75 years or older and patients with serious underlying diseases, follow-up observation was suggested to be one option in patients who give informed consent after receiving an explanation of the risk of recurrence.

Value and impact factors of multidetector computed tomography in diagnosis of preoperative lymph node metastasis in gastric cancer: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Multidetector computed tomography (MDCT) exhibited wide ranges of sensitivities and specificities for lymph node assessment of gastric cancer (GC) in several individual studies. This present meta-analysis was carried out to evaluate the value of MDCT in diagnosis of preoperative lymph node metastasis (LNM) and to explore the impact factors that might explain the heterogeneity of its diagnostic accuracy in GC.

METHODS

A comprehensive search was conducted to collect all the relevant studies about the value of MDCT in assessing LNM of GC within the PubMed, Cochrane library and Embase databases up to Feb 2, 2016. Two investigators independently screened the studies, extracted data, and evaluated the quality of included studies. The sensitivity, specificity, and area under ROC curve (AUC) were pooled to estimate the overall accuracy of MDCT. Meta-regression and subgroup analysis were carried out to identify the possible factors influencing the heterogeneity of the accuracy.

RESULTS

A total of 27 studies with 6519 subjects were finally included. Overall, the pooled sensitivity, specificity, and AUC were 0.67 (95% CI: 0.56-0.77), 0.86 (95% CI: 0.81-0.90), and 0.86 (95% CI: 0.83-0.89), respectively. Meta-regression revealed that MDCT section thickness, proportion of serosal invasion, and publication year were the main significant impact factors in sensitivity, and MDCT section thickness, multiplanar reformation (MPR), and reference standard were the main significant impact factors in specificity. After the included studies were divided into 2 groups (Group A: studies with proportion of serosa-invasive GC subjects ≥50%; Group B: studies with proportion of serosa-invasive GC subjects <50%), the pooled sensitivity in Group A was significantly higher than in Group B (0.84 [95% CI: 0.75-0.90] vs 0.55 [95% CI: 0.41-0.68], P < .01). For early gastric cancer (EGC), the pooled sensitivity, specificity, and AUC were 0.34 (95% CI: 0.15-0.61), 0.91 (95% CI: 0.84-0.95), and 0.83 (95% CI: 0.80-0.86), respectively.

CONCLUSION

To summarize, MDCT tends to be adequate to assess preoperative LNM in serosa-invasive GC, but insufficient for non-serosa-invasive GC (particularly for EGC) owing to its low sensitivity. Proportion of serosa-invasive GC subjects, MDCT section thickness, MPR, and reference standard are the main factors influencing its diagnostic accuracy.

Recent Advances in Endoscopy

In this narrative review, invited by the Editors of Gastroenterology, we summarize recent advances in the field of gastrointestinal endoscopy. We have chosen articles published primarily in the past 2-3 years. Although a thorough literature review was performed for each topic, the nature of the article is subjective and systematic and is based on the authors' experience and expertise regarding articles we believed were most likely to be of high clinical and scientific importance.

Factors associated with the efficacy of miniprobe endoscopic ultrasonography after conventional endoscopy for the prediction of invasion depth of early gastric cancer

BACKGROUND

This study aimed to compare the accuracy of conventional endoscopy (CE) and endoscopic ultrasonography (EUS) to predict tumor invasion depth and to determine factors associated with higher accuracy of additional miniprobe EUS after CE.

METHODS

Between May 2009 and February 2015, 273 lesions in 266 patients were subjected to miniprobe EUS after CE and curative treatment for well-to-moderately differentiated early gastric cancer (EGC). We reviewed preoperative CE and EUS findings and compared them to the pathologic findings.

RESULTS

The accuracy of CE and EUS to estimate the invasion depth of EGCs was 78.8% (215/273) and 83.9% (229/273) (p = .124), respectively. Using multivariate analysis, irregular depressed surface (odds ratio [OR] 8.11; 95% confidence interval [CI]: 2.79-23.53), fold change (OR 7.22; 95% CI: 2.33-22.38), size >2 cm (OR 2.72; 95% CI: 1.15-6.42) and ulcer scar (OR 2.64; 95% CI: 1.07-6.49) were associated with the higher accuracy of EUS than that of CE.

CONCLUSIONS

Routine assessment using miniprobe EUS did not increase the accuracy of predicting invasion depth, compared to CE. However, EUS could be helpful in the treatment decision-making process for EGCs with lesions having irregular surfaces, fold change, size >2 cm, or ulcer scar.

Model to identify early-stage gastric cancers with deep invasion of submucosa based on endoscopy and endoscopic ultrasonography findings

BACKGROUND

Conventional endoscopy and endoscopic ultrasonography (EUS) are used to estimate the invasion depth of early-stage gastric cancers (EGCs), but estimates made by either technique are often inaccurate. We developed a model to determine the invasion depth of EGCs using conventional endoscopy and EUS findings, with pathology results as the reference.

METHODS

We performed a retrospective study of 195 patients (205 lesions) diagnosed with gastric cancers who underwent endoscopy and EUS followed by resection. Based on pathology analyses, lesions (n = 205) were assigned to categories of: mucosa invasion or minute invasion into the submucosal layer less than 500 μm from the muscularis mucosae (M-SM1) or penetration of 500 μm or more (≥SM2). The lesions were randomly assigned to derivation (138 lesions) and validation sets (67 lesions). A depth predictive model was proposed in the derivation set using multivariate logistic regression analyses. The discriminative power of this model was assessed in both sets.

RESULTS

Remarkable redness (OR 5.42; 95% CI 1.32-22.29), abrupt cutting of converging folds (OR 8.58; 95% CI 1.65-44.72), lesions location in the upper third of the stomach (OR 10.26; 95% CI 2.19-48.09), and deep invasion based on EUS findings (OR 16.53; 95% CI 4.48-61.15) significantly associated with ≥SM2 invasion. A model that incorporated these 4 variables discriminated between M-SM1 and ≥SM2 lesions with the area under the ROC curve of 0.865 in the derivation set and 0.797 in the validation set. In the derivation set, a cut-off score of 8 identified lesions as ≥SM2 with 54% sensitivity and 97% specificity. The model correctly predicted the invasion depth 89.86% of lesions; it overestimated the depth of 2.17% of lesions.

CONCLUSIONS

We developed a model to identify EGCs with invasion depth ≥SM2 based on endoscopy and EUS findings. This model might reduce overestimation of gastric tumor depth and prevent unnecessary gastrectomy.

Usefulness of the S-O clip for gastric endoscopic submucosal dissection (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is technically one of the most complicated endoscopic procedures. Traction methods have been reported to be effective for ESD. A recent study revealed that the S-O clip allowed faster and safer colonic ESD. We assessed the efficacy and safety of gastric ESD with the S-O clip for gastric epithelial neoplasm.

METHODS

We performed a retrospective cohort study of patients treated for gastric ESD using the S-O clip between September and November 2016 (SO group, n = 48). The subjects were matched with patients treated with conventional gastric ESD from September 2015 to August 2016 (control group, n = 258) at Sendai Kousei Hospital, a tertiary endoscopic center. The primary outcome was procedure time. Multivariate logistic regression and propensity score matching analyses were performed to reduce the effects of selection bias for potential confounding factors differences like age, sex, lesion location, lesion position, presence of ulcer scarring, resected specimen size, and operator experiences.

RESULTS

Forty-eight pairs were created after propensity score matching. The mean procedure time (including the S-O clip attachment time) was significantly shorter in the SO group (47.2 ± 24.6 vs. 69.2 ± 67.1 min, p = 0.035). The mean clip attachment time was 4.4 (range 2-15) min. There were no significant differences in other treatment outcomes (en-bloc resection rate: 100 vs. 100%, p = 1.000; perforation rate: 0 vs. 2.1%, p = 0.315; delayed bleeding rate: 2.1 vs. 4.3%, p = 0.558).

CONCLUSIONS

The S-O clip improved the speed of gastric ESD by approximately 25%, without increasing adverse events.

Evaluation of the bleeding risk with various antithrombotic therapies after gastric endoscopic submucosal dissection

BACKGROUND AND STUDY AIMS

Patients receiving antithrombotic drugs have a higher risk of postoperative bleeding and thromboembolic events related to endoscopic procedures. The aim of this study was to evaluate the relationship between various antithrombotic therapies and bleeding after gastric endoscopic submucosal dissection (ESD) (post-ESD bleeding).

PATIENTS AND METHODS

 Among 529 consecutive gastric ESD procedures (483 patients with 579 legions), 100 patients with 121 lesions who underwent 108 procedures were on antithrombotic therapy (group A) and 382 patients with 458 lesions who underwent 421 procedures were not on antithrombotic therapy (group B). The ratio of post-ESD bleeding between the two groups and the bleeding risk related to various antithrombotic therapies were investigated.

RESULTS

Postoperative bleeding was more frequent in group A (11.1 %) than in group B (3.3 %). No thromboembolic events were reported in either group. Further investigation of antithrombotic therapies in group A demonstrated that various combinations of antithrombotic agents and heparin replacement were associated with a higher ratio of post-ESD bleeding. Multivariate analyses revealed that dual antiplatelet therapy (odds ratio [OR] 10.9, 95 % confidence interval [CI] 2.1 - 49.5; P  = 0.005) and heparin replacement (OR 34.4, 95 %CI 9.4 - 133.2; P  < 0.001) were associated with the increased risk of post-ESD bleeding. In patients on antiplatelet therapy, post-ESD bleeding tended to occur in the early postoperative period compared with patients on anticoagulant therapy.

CONCLUSIONS

 It is necessary to be cautious regarding post-ESD bleeding in patients requiring antithrombotic therapy, especially patients receiving dual antiplatelet therapy and heparin replacement. A further prospective study with a large sample will be needed to confirm these findings.

Concomitant stromal tumor and early cancer of the stomach: What should be done?

Concomitant gastric stromal tumor (GST) and gastric cancer (GC) is uncommon; even more uncommon is a concomitant GST and early stage GC (EGC). Tumor resection by endoscopic submucosal dissection (ESD) for concomitant GST and EGC has not been reported. We sought to define the clinical importance of detection of concomitant GST and EGC during the first esophagogastroduodenoscopy (EGD), and compare the clinical outcomes of ESD versus radical surgery for the treatment of concomitant GST and EGC. Our investigation was a retrospective cohort study. Patients with concomitant GST and EGC who underwent ESD or radical surgery were enrolled at the university-affiliated hospital from January 2005 to January 2015. The detection rate of concomitant GST and EGC during the first EGD was 3/25 (12%). Among 25 patients, 14 underwent ESD and 11 underwent surgery. Mean operation time and hospital stay were significantly shorter in the ESD group than the surgery group. There were no significant differences in terms of rates of en bloc resection, complete resection, and early complications. Late complications were more common in the surgery group than in the ESD group. The median follow-up duration was 58.9 months. Three- or 5-year overall survival rates were 100% for both groups and no patient died of EGC and GST. There was no local recurrence in the 2 groups; however, 3 metachronous EGC lesions were found during the follow-up period in the ESD group as follows: the simultaneous occurrence of GST and EGC was uncommon; the detection rate of concomitant GST and EGC was very low at the first EGD; and ESD appeared to be a safe, efficient, and popular treatment option for concomitant GST and EGC, that met the ESD absolute indication, and the outcomes were comparable to those achieved with surgery.

Long-term oncological outcomes of submucosal manipulation during non-curative endoscopic submucosal dissection for submucosal invasive gastric cancer: a multicenter retrospective study in Japan

BACKGROUND

Sufficient information is not available on the extent to which lymph node metastasis (LNM) and prognosis are affected by submucosal manipulation during endoscopic submucosal dissection (ESD) for submucosal invasive gastric cancer (SMGC). We aimed to identify the effects of submucosal manipulation during ESD on LNM and prognosis in patients with SMGC.

METHODS

From 19 institutions in Japan, 2526 patients who failed to meet the current curative criteria for ESD between 2000 and 2011 were recruited. After exclusion, 1969 patients were remained. Based on the treatment strategy after ESD, 1064 patients underwent additional radical surgery. A total of 890 of 1064 patients with SMGC, LNM and cancer recurrence, and prognosis were retrospectively reviewed.

RESULTS

The median follow-up duration was 67 months. A total of 214 patients had SM1 (depth of tumor invasion from the muscularis mucosae <500 μm) invasive cancer and 676 patients had SM2 (depth of tumor invasion from the muscularis mucosae ≥500 μm) invasive cancer. LNM was found in 84 patients (9.4%), and 14 patients (1.6%) developed cancer recurrence. The 3-year and 5-year overall survival rates were 96.1 and 91.7%, respectively. The 3-year and 5-year disease-specific survival rates were 99.3 and 98.5%, respectively.

CONCLUSIONS

The rates of LNM and cancer recurrence, and prognosis of patients who underwent additional radical surgery after non-curative ESD for SMGC were excellent. Submucosal manipulation during ESD for SMGC does not seem to enhance the risk for LNM or worsen the prognosis compared to surgical series.

Clinical outcomes of non-curative endoscopic submucosal dissection with negative resected margins for gastric cancer

BACKGROUND AND AIMS

There has been little information about the long-term outcomes of patients with early gastric cancer (EGC) treated by non-curative endoscopic submucosal dissection (ESD) with negative resected margins (R0 resection). We aimed to compare the clinical outcomes of non-curative ESD with R0 resection between patients who underwent additional gastrectomy and those who did not.

METHODS

Among EGC patients treated by ESD from 2002 to 2010, 66 patients were treated by non-curative ESD with R0 resection. Patients received either additional gastrectomy (group A, n = 45) or were followed up without gastrectomy (group B, n = 21). The clinicopathologic findings and the subsequent clinical course were compared between the 2 groups.

RESULTS

Patients in group A were younger than those in group B (68.0 vs 71.0 years, P = .006). The follow-up period was longer in group A than in group B (7.8 vs 5.9 years, P = .011). The percentage of patients who died of any cause was not statistically lower in group A than in group B (13.3% vs 33.3%, P = .06). Although the overall survival rate was higher in group A than in group B (93.3% vs 76.2%, P = .028), disease-specific survival rates did not differ between the 2 groups (97.8% vs 100%, P = .495). A Cox proportional hazards model showed that gastrectomy was not an independent factor associated with overall survival.

CONCLUSIONS

Careful follow-up may be an alternative strategy to gastrectomy for a subgroup of patients treated by non-curative ESD with R0 resection.

A Scoring System to Stratify Curability after Endoscopic Submucosal Dissection for Early Gastric Cancer: "eCura system"

OBJECTIVES

Although radical surgery is recommended for patients not meeting the curative criteria for endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) because of the potential risk of lymph node metastasis (LNM), this recommendation may be overestimated and excessive. We aimed to establish a simple scoring system for decision making after ESD.

METHODS

This multicenter retrospective study consisted of two stages. First, the risk-scoring system for LNM was developed using multivariate logistic regression analysis in 1,101 patients who underwent radical surgery after having failed to meet the curative criteria for ESD of EGC. Next, the system was internally validated by survival analysis in another 905 patients who also did not meet the criteria and did not receive additional treatment after ESD.

RESULTS

In the development stage, based on accordant regression coefficients, five risk factors for LNM were weighted with point values: three points for lymphatic invasion and 1 point each for tumor size >30 mm, positive vertical margin, venous invasion, and submucosal invasion ≥500 μm. Then, the patients were categorized into three LNM risk groups: low (0-1 point: 2.5% risk), intermediate (2-4 points: 6.7%), and high (5-7 points: 22.7%). In the validation stage, cancer-specific survival differed significantly among these groups (99.6, 96.0, and 90.1%, respectively, at 5 years; P<0.001). The C statistic of the system for cancer-specific mortality was 0.78.

CONCLUSIONS

This scoring system predicted cancer-specific survival in patients who did not meet the curative criteria after ESD for EGC. ESD without additional treatment may be an acceptable option for patients at low risk.

Prediction model for non-curative resection of endoscopic submucosal dissection in patients with early gastric cancer

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is a useful method for complete resection of early gastric cancer (EGC). However, there are still some patients who undergo additional gastrectomy after ESD because of non-curative resection. There is no model that can accurately predict non-curative resection of ESD. We aimed to create a model for predicting non-curative resection of ESD in patients with EGC.

PATIENTS AND METHODS

We reviewed the medical records, including all gross findings of EGC, of patients who underwent ESD for EGCs. We divided the patients into a non-curative resection group and a curative resection group. The clinicopathologic characteristics were compared between the groups to identify the risk factors for non-curative resection of ESD. We created a scoring system based on logistic regression modeling and bootstrap validation.

RESULTS

Of 1639 patients who had undergone ESD for EGCs, 272 were identified as being treated non-curatively with ESD. A large tumor size (≥20 mm), tumor location in the upper body of the stomach, the presence of ulcer, fusion of gastric folds, the absence of mucosal nodularity, spontaneous bleeding, and undifferentiated tumor histology were associated with non-curative resection of ESD. Points of risk scores were assigned for these variables based on the β coefficient as follows: tumor size (≥20 mm), 2 points; tumor location in the upper body of the stomach, 1 point; ulcer, 2 points; fusion of gastric folds, 2 points; absence of mucosal nodularity, 1 point; spontaneous bleeding, 1 point; and undifferentiated histology, 2 points. Our risk scoring model showed good discriminatory performance on internal validation (bootstrap-corrected area under the receiver operating characteristic curve, 0.7004; 95% confidence interval, 0.6655-0.7353).

CONCLUSIONS

We developed a validated prediction model that can be used to identify patients who will undergo non-curative resection of ESD. Our prediction model can provide useful information for making decisions about the treatment of EGC before performing ESD.

Endoscopic Management of Early Gastric Adenocarcinoma and Preinvasive Gastric Lesions

Early gastric cancer (ECG) can be difficult to diagnose endoscopically. Endoscopists should be familiar with subtle changes and endoscopic features of EGC. Chromoendoscopy and image-enhanced endoscopy improve diagnostic accuracy and facilitate endoscopic resection. Endoscopic submucosal dissection is a preferred endoscopic technique for resection of EGC and offers a comparable overall survival to surgical resection. Endoscopic management of benign gastric epithelial polyps (fundic gland polyps, hyperplastic polyps, and gastric adenoma) depends on patient symptomatology, patient's comorbidities (eg, familial syndromes), lesions' characteristics, and risk of malignant transformation. This article provides an overview of endoscopic management of EGC and common premalignant gastric lesions.

Role of targeted biopsy under magnifying endoscopy with narrow band imaging may be not necessary: a prospective diagnostic accuracy study

BACKGROUND AND AIMS

Targeted biopsy under the guidance of magnifying endoscopy with narrow band imaging (ME-NBI) has higher accuracy than endoscopic forceps biopsy (EFB) in the differential diagnosis of cancerous lesions from noncancerous lesions. The aims of this study were to validate diagnostic efficacy of targeted biopsy under the guidance of ME-NBI (MNTB) and further evaluate whether it is necessary to perform MNTB when combined with ME-NBI.

METHODS

This study prospectively analyzed 211 gastric lesions of suspected cancerous tissues. The sensitivity, specificity, positive predictive value, and negative predictive value of EFB, ME-NBI, MNTB, EFB plus ME-NBI, and MNTB plus ME-NBI for the diagnosis of cancerous lesions were determined, respectively. The accuracy, sensitivity, specificity of EFB and MNTB, EFB plus ME-NBI, and MNTB plus ME-NBI were also compared, respectively.

RESULTS

The accuracy, sensitivity, and specificity with 95% confidence intervals were 68.2% (61.4-74.4%), 62.3% (54.1-69.9%), 84.2% (71.6-92.1%) for EFB, 75.4% (68.9-80.9%), 72.7% (64.9-79.4%), 82.5% (69.6-90.8%) for MNTB, 76.8% (70.4-82.2%), 73.4% (65.5-80.0%), 86.0% (73.7-93.3%) for ME-NBI, 82.0% (76.0-86.8%), 85.7% (79.0-90.6%), 71.9% (58.3-82.6%) for EFB plus ME-NBI, 84.8% (79.1-89.3%), 89.6% (83.4-93.8%), and 71.9% (58.3-82.6%) for MNTB plus ME-NBI, respectively. The sensitivity of MNTB was significantly higher than that of EFB (P=0.048). There was no significant difference in the sensitivity (P=0.307), specificity (P=1.000), and accuracy (P=0.337) between EFB plus ME-NBI and MNTB plus ME-NBI.

CONCLUSION

Although MNTB has a higher diagnostic efficacy than EFB in the diagnosis of cancerous lesions, it may be not necessary to perform MNTB when combined with ME-NBI.

Technological review on endoscopic submucosal dissection: available equipment, recent developments and emerging techniques

Endoscopic submucosal dissection (ESD) is widely practiced in Japan and the Eastern World and is rapidly expanding in western countries for the management of early malignancies of the upper and lower gastrointestinal tube. In addition, novel therapeutic applications deriving from ESD have emerged including the treatment of achalasia, of submucosal tumors, of diverticula, of strictures and of reflux disease. An ESD procedure necessitates not only skills and specific training, but also familiarization with a vast spectrum of devices (endoscopes, high-frequency generators and their settings, endoknives, hoods, irrigation devices) and techniques (such as countertraction, artificial ulcer closure), that render the procedure faster, more efficient and safer. This technological article gives an overview on current and novel equipment for an ESD and associated techniques.

Is radical surgery necessary in all patients who do not meet the curative criteria for endoscopic submucosal dissection in early gastric cancer? A multi-center retrospective study in Japan

BACKGROUND

Although radical surgery is routinely performed for patients who do not meet the curative criteria for endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) due to the risk of lymph node metastasis (LNM), this standard therapeutic option may be excessive given the lower number of patients with LNM. Therefore, we aimed to investigate long-term outcomes and validate risk factors predicting recurrence after ESD.

METHODS

Of 15,785 patients who underwent ESD for EGC at 19 institutions between 2000 and 2011, 1969 patients not meeting the curative criteria were included in this multi-center study. Based on the treatment strategy after ESD, patients were divided into radical surgery (n = 1064) and follow-up (no additional treatment, n = 905) groups.

RESULTS

Overall survival (OS) and disease-specific survival (DSS) were significantly higher in the radical surgery group than in the follow-up group (p < 0.001 and p = 0.012, respectively). However, the difference in 3-year DSS between the groups (99.4 vs. 98.7 %) was rather small compared with the difference in 3-year OS (96.7 vs. 84.0 %). LNM was found in 89 patients (8.4 %) in the radical surgery group. Lymphatic invasion was found to be an independent risk factor for recurrence in the follow-up group (hazard ratio 5.23; 95 % confidence interval 2.01-13.6; p = 0.001).

CONCLUSIONS

This multi-center study, representing the largest cohort to date, revealed a large discrepancy between OS and DSS in the two groups. Since follow-up with no additional treatment after ESD may be an acceptable option for patients at low risk, further risk stratification is needed for appropriate individualized treatment strategies.

Additional surgical resection after endoscopic mucosal dissection for early gastric cancer: A medium-sized hospital's experience

PURPOSE

In Japan, the majority of early gastric cancers (EGCs) are now treated with endoscopic submucosal dissection (ESD). Patients with non-curative lesions treated by ESD are advised to undergo additional surgical resection (ASR) based on guidelines from the Japan Gastroenterological Endoscopy Society (JGES) and Japanese Gastric Cancer Association (JGCA). However, many studies have demonstrated that residual cancer and lymph node metastasis are only rarely found in ASR specimens. Here we retrospectively analyzed the conditions that could enable the avoidance of unnecessary ASR.

METHODS

The ESD data for 114 absolute indication lesions and 26 lesions of expanded indication lesions were analyzed. The indications and the curability were evaluated according to the JGES/JGCA guidelines.

RESULTS

The rates of non-curative resection and ASR were significantly higher in the expanded indication group compared to the absolute indication group (26.9% and 19.2% vs. 7.9% and 0.9%, respectively). ASR was performed for six patients. Three of their ARS specimens contained neither residual cancer nor lymph node metastasis, and the pathological findings of the preceding ESD specimens deviated slightly from the curative criteria defined by the guidelines. The conditions of the lesions that did not meet the curative criteria were as follows: (1) sm1 invasion of undifferentiated-type lesion <10 mm dia., (2) 21-25 mm dia. mucosal undifferentiated-type lesion, or (3) peacemeal resection with a horizontal margin positive for the mucosal differentiated-type.

CONCLUSIONS

These data suggest that a close follow-up without ASR might be appropriate for patients in the above-mentioned three categories after non-curative ESD for EGC.

Clinical relevance of aberrant polypoid nodule scar after endoscopic submucosal dissection

AIM

To describe a series of patients with aberrant polypoid nodule scar developed after gastric endoscopic submucosal dissection (ESD), and to discuss its pathogenesis and clinical management.

METHODS

We reviewed retrospectively the endoscopic database of two academic institutions located in Brazil and Japan and searched for all patients that underwent ESD to manage gastric neoplasms from 2003 to 2015. The criteria for admission in the study were: (1) successful en bloc ESD procedure with R0 and curative resection confirmed histologically; (2) postoperative endoscopic examination with identification of a polypoid nodule scar (PNS) at ESD scar; (3) biopsies of the PNS with hyperplastic or regenerative tissue, reviewed by two independent experienced gastrointestinal pathologists, one from each Institution. Data were examined for patient demographics, Helicobacter pylori status, precise neoplastic lesion location in the stomach, tumor size, histopathological assessment of the ESD specimen, and postoperative information including medical management, endoscopic and histological findings, and clinical outcome.

RESULTS

A total of 14 patients (10 men/4 women) fulfilled the inclusion criteria and were enrolled in this study. One center contributed with 8 cases out of 60 patients (13.3%) from 2008 to 2015. The second center contributed with 6 cases (1.7%) out of 343 patients from 2003 to 2015. Postoperative endoscopic follow-up revealed similar findings in all patients: A protruded polypoid appearing nodule situated in the center of the ESD scar surrounded by convergence of folds. Biopsies samples were taken from PNS, and histological assessment revealed in all cases regenerative and hyperplastic tissue, without recurrent tumor or dysplasia. Primary neoplastic lesions were located in the antrum in 13 patients and in the angle in one patient. PNS did not develop in any patient after ESD undertaken for tumors located in the corpus, fundus or cardia. All patients have been followed systematically on an annual basis and no malignant recurrence in the ESD scar has been identified (mean follow-up period: 45 mo).

CONCLUSION

PNS may occur after ESD for antral lesions and endoscopically look concerning, especially for the patient or the family doctor. However, as long as curative R0 resection was successfully achieved and histology demonstrates only regenerative and hyperplastic tissue, PNS should be viewed as a benign alteration that does not require any type of intervention, other than endoscopic surveillance.

Endoscopic mucosal resection and endoscopic submucosal dissection of large colonic polyps

Almost all large and complex colorectal polyps can now be resected endoscopically. Piecemeal endoscopic mucosal resection (PEMR) is an established technique with fairly low complication risk and good short-term and medium-term outcomes. Several modifications to the basic injection and snare technique have been developed contributing to safer and more complete resections. Delayed bleeding requiring reintervention is the most troublesome complication in 2-7% of patients, particularly in those with comorbidities and large, right-sided polyps. Endoscopic submucosal dissection (ESD) has become popular in Japan and has theoretical advantages over PEMR in providing a complete, en bloc excision for accurate histological staging and reduced local recurrence. These advantages come at the cost of a more complex, expensive and time-consuming procedure with a higher risk of perforation, particularly early in the procedure learning curve. These factors have contributed to the slow adoption of ESD in the West and the challenge to develop new devices and endoscopic platforms that will make ESD easier and safer. Currently, ESD indications are limited to large rectal lesions, in which procedural complications are easily managed, and for colorectal polyps with a high risk of containing tiny foci of early submucosally invasive cancer, whereby ESD may be curative compared with PEMR.

Effectiveness of endoscopic gastric cancer screening in a rural area of Linzhou, China: results from a case-control study

In China, a large burden of gastric cancer has remained, and endoscopic screening was expected to reduce gastric cancer mortality. Therefore, a population‐based case–control study was conducted to evaluate the screening effect. The gastric cancer screening program was initiated in Linzhou in the year 2005, and endoscopic examination with indicative biopsy, for residents aged 40–69 years, was used to detect early cancer and precancerous lesion. In this study, cases were defined as individuals who had died of gastric cancer, which were selected from Linzhou Cancer Registry database. Controls were residents (six per case), who had not died of gastric cancer, from the same area as the case, and matched by gender and age (±2 years). The exposure status, whether cases and controls ever attended the screening or not, was acquired by inspecting the well‐documented screening records. Conditional logistic regression model was used to estimate the odds ratios (OR) and their 95% confidence intervals (95% CI). A total of 313 cases and 1876 controls were included in our analysis. Compared with subjects who never participated in screening, the overall OR for individuals who ever participated in screening was 0.72(95% CI: 0.54–0.97). The OR for lag time 4 years or longer was 0.68(95% CI: 0.47–0.98) and the OR for those who were aged 50–59 years were 0.56 (0.37–0.85). The results suggest a 28% reduction in risk of gastric cancer mortality by endoscopic screening, which may have significant implications for gastric cancer screening in rural areas of China.

Effectiveness of clip-and-snare method using pre-looping technique for gastric endoscopic submucosal dissection

AIM: To evaluate efficacy and safety of clip-and-snare method using pre-looping technique (CSM-PLT) for gastric endoscopic submucosal dissection (ESD).

METHODS: In the CSM-PLT method, a clip attached to the lesion side was strangulated with a snare, followed by application of an appropriate tension to the lesion independent of an endoscope. Twenty consecutive lesions were resected by ESD using CSM-PLT (CSM-PLT group) and compared with a control group, including 20 lesions that were resected by conventional ESD. The control group was matched based on the size and location of the lesion, presence of pathologic fibrosis, and experience of endoscopists. Total procedure time of ESD, proportion of en bloc resection, and complications were analyzed.

RESULTS: The total procedure time for the CSM-PLT group was significantly shorter than that for the control group (38.5 min vs 59.5 min, P = 0.023); all lesions were resected en bloc by ESD. There was no significant difference in complications between the two groups. Moreover, there was no complication in the CSM-PLT group. In one large lesion (size: 74 mm) that underwent extensive CSM-PLT during ESD, we used an additional CSM-PLT on another edge of the lesion after achieving submucosal resection to the maximum extent possible during initial CSM-PLT. In two lesions, the snare came off the lesion together with the clip after a sudden pull; nevertheless, ESD was successful in all lesions.

CONCLUSION: CSM-PLT was an effective and safe method for gastric ESD.

Guidelines for endoscopic management of non-variceal upper gastrointestinal bleeding

Japan Gastroenterological Endoscopy Society (JGES) has compiled a set of guidelines for endoscopic management of non-variceal upper gastrointestinal bleeding using evidence-based methods. The major cause of non-variceal upper gastrointestinal bleeding is peptic gastroduodenal ulcer bleeding. As a result, these guidelines mainly focus on peptic gastroduodenal ulcer bleeding, although bleeding from other causes is also overviewed. From the epidemiological aspect, in recent years in Japan, bleeding from drug-related ulcers has become predominant in comparison with bleeding from Helicobacter pylori (HP)-related ulcers, owing to an increase in the aging population and coverage of HP eradication therapy by national health insurance. As for treatment, endoscopic hemostasis, in which there are a variety of methods, is considered to be the first-line treatment for bleeding from almost all causes. It is very important to precisely evaluate the severity of the patient's condition and stabilize the patient's vital signs with intensive care for successful endoscopic hemostasis. Additionally, use of antisecretory agents is recommended to prevent rebleeding after endoscopic hemostasis, especially for gastroduodenal ulcer bleeding. Eighteen statements with evidence and recommendation levels have been made by the JGES committee of these guidelines according to evidence obtained from clinical research studies. However, some of the statements that are supported by a low level of evidence must be confirmed by further clinical research.

Endoscopic antralplasty for severe gastric stasis after wide endoscopic submucosal dissection in the antrum

A 75-year-old female underwent esophagogastroduodenoscopy, revealing a widely spreading tumor occupying the anterior wall, lesser curvature, and posterior wall of the antrum and lower body. Endoscopic submucosal dissection was performed and resulted in more than five-sixths circumferential antral mucosal resection. One month later, she complained of nausea, vomiting, and abdominal distention. Endoscopy showed residual food in the stomach and deformation of the antrum with traction toward the contracted scar in the lesser curvature. The pyloric ring could not be seen from the antrum although the endoscope was able to pass easily beyond the area of deformation and the pyloric ring was intact. Despite repeated endoscopic balloon dilations, the patient’s symptoms remained refractory. The problem was speculated to be not due to any potential stricture but to antrum deformation resulting from the traction force toward the healing ulcer. We hypothesized that an additional countertraction force opposite the previous ESD site might resolve the problem, and ESD of approximately 2.5 cm size was performed in the greater curvature of the antrum. Along with development of a scar, traction toward the greater curvature was added, and the pyloric ring could be observed on repeat esophagogastroduodenoscopy. The symptoms were also gradually ameliorated. Afterwards, the endoscopic findings have now been unchanged during 7 years of follow-up.

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.