Endoscopic submucosal dissection as a treatment for gastric noninvasive neoplasia: a multicenter study by Osaka University ESD Study Group

A machine learning model for predicting the lymph node metastasis of early gastric cancer not meeting the endoscopic curability criteria

BACKGROUND

We developed a machine learning (ML) model to predict the risk of lymph node metastasis (LNM) in patients with early gastric cancer (EGC) who did not meet the existing Japanese endoscopic curability criteria and compared its performance with that of the most common clinical risk scoring system, the eCura system.

METHODS

We used data from 4,042 consecutive patients with EGC from 21 institutions who underwent endoscopic submucosal dissection (ESD) and/or surgery between 2010 and 2021. All resected EGCs were histologically confirmed not to satisfy the current Japanese endoscopic curability criteria. Of all patients, 3,506 constituted the training cohort to develop the neural network-based ML model, and 536 constituted the validation cohort. The performance of our ML model, as measured by the area under the receiver operating characteristic curve (AUC), was compared with that of the eCura system in the validation cohort.

RESULTS

LNM rates were 14% (503/3,506) and 7% (39/536) in the training and validation cohorts, respectively. The ML model identified patients with LNM with an AUC of 0.83 (95% confidence interval, 0.76-0.89) in the validation cohort, while the eCura system identified patients with LNM with an AUC of 0.77 (95% confidence interval, 0.70-0.85) (P = 0.006, DeLong's test).

CONCLUSIONS

Our ML model performed better than the eCura system for predicting LNM risk in patients with EGC who did not meet the existing Japanese endoscopic curability criteria. We developed a neural network-based machine learning model that predicts the risk of lymph node metastasis in patients with early gastric cancer who did not meet the endoscopic curability criteria.

Long-term outcomes after endoscopic submucosal dissection for relative indication early gastric cancer in nonsurgical candidates

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is effective in treating early gastric cancer (EGC). Its role in patients with comorbidities along with more advanced disease is unknown. We sought to evaluate this in a large Western cohort.

METHODS

Consecutive patients who underwent ESD for EGC in a single tertiary Western endoscopy center over 10 years were prospectively analyzed. The primary outcomes were long-term overall survival (OS) and disease-free survival (DFS) up to 5 years. Secondary outcomes were efficacy and serious adverse events (SAEs).

RESULTS

ESD for 157 cases of EGC in 149 patients was performed in an elderly and comorbid cohort with a mean age of 73.7 years and age-adjusted Charlson Comorbidity Index of 4.2. Over a median follow-up of 51.6 months, no significant differences were found in 5-year OS (88.9% vs 77.9%, P = .290) and DFS (83.2% vs 75.1%, P = .593) between absolute indication (AI) EGC and relative indication (RI) EGC. The AI EGC cohort achieved higher en-bloc (96.3% vs 87.5%, P = .069) and R0 resection rates (93.6% vs 62.5%, P < .001) when compared with RI EGC. No significant differences were found in SAEs (7.3% vs 12.5%, P = .363). No mortality or surgical resection ensued from adverse events from ESD.

CONCLUSIONS

ESD safely confers DFS in poor surgical candidates with RI EGC in a large Western cohort. Patients who are elderly and/or with comorbidities or decline surgical resection may benefit from ESD and avoid the risks of surgery and its long-term sequelae. (Clinical trial registration number: NCT02306707.).

Characteristics and Risk Factors of Delayed Perforation in Endoscopic Submucosal Dissection for Early Gastric Cancer

(1) Background: Delayed perforation after gastric endoscopic submucosal dissection (ESD) for early gastric cancer is a relatively uncommon and serious complication that sometimes requires emergency surgery. This study aimed to determine the clinicopathological features, risk factors, and appropriate management strategies for delayed perforation. (2) Methods: This study included 735 patients with 791 lesions who underwent ESD for early gastric cancer at a single institution between July 2009 and June 2019. We retrospectively compared the clinical features of patients with and without delayed perforations. (3) Results: The incidence of delayed perforations was 0.91%. The identified risk factors included a postoperative stomach condition and histopathological ulceration. A comparison between delayed and intraoperative perforations revealed a postoperative stomach condition as a characteristic risk factor for delayed perforation. Patients with delayed perforation who avoided emergency surgery tended to exhibit an earlier onset of symptoms such as abdominal pain and fever. No peritoneal seeding following delayed perforation was observed for any patient. (4) Conclusions: A postoperative stomach condition and histopathological ulceration were risk factors for delayed perforation. Delayed perforation is a significant complication that requires careful monitoring after gastric ESD for early gastric cancer, particularly in patients with postoperative gastric conditions.

Treatment with vonoprazan for 3 weeks is not inferior to 8 weeks for the management of gastric ESD: a multicenter noninferiority randomized study

BACKGROUND

Vonoprazan, a potassium-competitive acid blocker (VPZ), significantly reduces postoperative bleeding after gastric ESD; however, there is no consensus on the appropriate treatment duration. We conducted a randomized controlled study to demonstrate that the 3-week administration of VPZ is not inferior to the 8-week administration for ulcer healing.

METHODS

This is a prospective, open-label multicenter randomized controlled trial. Patients aged 20-85 years undergoing gastric ESD were included in this study. The key exclusion criteria were patients with bleeding tendencies and those taking NSAIDs, steroids, PPIs, or VPZ medications. Eligible patients were randomly assigned to the VPZ 3w or 8w treatment group. The primary endpoint was the proportion of patients with complete closure of the post-ESD wound at 24 weeks after ESD. The key secondary endpoints included the proportion of patients with complete closure of the post-ESD wound at 8 weeks and the proportion of bleeding or perforation more than 3 weeks after ESD.

RESULTS

From May 2018 to October 2020, 234 patients were included. The proportion of patients with complete ulcer closure was significantly lower in the 3w group than in the 8w group (70.8% vs. 90.6%) at 8 weeks post-treatment. The complete closure rates at 24 weeks in the 3w and 8w groups were 99.1% and 99.2%, respectively. The absolute difference in the closure rate at 24 weeks was - 0.059% [95% confidence interval (CI) -3.4% to 3.2], and the lower limit of the 95% CI exceeded -10%, the preset threshold. None of the patients developed delayed bleeding 3 weeks after ESD.

CONCLUSION

This multicenter randomized study demonstrated that 3 weeks of treatment with VPZ is sufficient for ulcer healing. Trial registry number. UMIN000031564.

Endoscopic Submucosal Dissection for Large Duodenal Laterally Spreading Lesions is Feasible: A Multi-Center Retrospective Study

BACKGROUND AND AIMS

This retrospective study aimed to evaluate the effect and safety of endoscopic submucosal dissection (ESD) for large laterally spreading lesions located in the descending duodenum based on multi-center experiences.

METHODS

This multicentric retrospective study included 3 hospitals in China. Fifty-one patients with laterally spreading lesions of the duodenum who underwent ESD between February 2019 and December 2020 were enrolled. The en bloc resection rates, en bloc R0 resection rates, complication rates, and local recurrence after ESD were evaluated.

RESULTS

Of the 51 patients, the median age was 62 years old (ranging from 37 to 76 years old); among them, 29 were male and 22 were female. The average lesion size was 2.3 cm (ranging from 1.5 to 4.0 cm). All 51 lesions achieved en bloc R0 resection successfully, with the procedure time ranging from 20 to 117 min (median: 45.5 min). The hospital length of stay ranged from 4 to 90 days (median: 8.0 d). Two patients experienced delayed bleeding 3 days after ESD and 2 other patients were diagnosed with delayed perforation. Tumor residual and local recurrence did not occur during a short follow-up period.

CONCLUSIONS

ESD for laterally spreading lesions of the descending duodenum is feasible.

Feasibility of olfactomedin 4 as a molecular biomarker for early diagnosis of gastric neoplasia after intestinal metaplasia

OBJECTIVES

This study discusses whether olfactomedin 4 (OLFM4) could be used as a sensitive and specific biomarker in the early diagnosis of gastric cancer (GC) after gastric intestinal metaplasia (GIM).

METHODS

An integrative analysis combining data derived from the Gene Expression Omnibus (GEO) and cBioPortal databases was performed to investigate the potential molecular biomarker. Immunohistochemistry and quantitative real-time polymerase chain reactions were used to measure the expression of messenger ribonucleic acid (mRNA) and protein by OLFM4. In combination with the gastroscopic findings and the OLFM4 expression in GIM-GC, a predictive model was established. The receiver operator characteristic curve (ROC) was applied to assess the diagnostic value of the model for GIM-GC.

RESULTS

According to the GEO and cBioPortal databases, OLFM4 was identified as a key gene in the diagnosis of GIM-GC. Higher protein expression of OLFM4 was found in GIM and GIM-GC compared with chronic superficial gastritis (GS) (p < 0.05). The positive expression rate of OLFM4 in paracancerous tissue (GCP) was higher than in GIM (p > 0.05). There was no significant difference between GIM-GC and GCP (p > 0.05). The mRNA expression of OLFM4 was similar to the protein expression, and the positive expression rate was higher in early GIM-GC than in GIM (p < 0.05).

CONCLUSION

Olfactomedin 4 could be used as a biomarker for the early diagnosis of GIM-GC, and the logistic predictive model could be an effective tool for increasing the early diagnostic rate.

A Prediction Model Based on the Risk Factors Associated with Pathological Upgrading in Patients with Early-Stage Gastric Neoplasms Diagnosed by Endoscopic Forceps Biopsy

Background/Aims

The discrepancies between the diagnosis of preoperative endoscopic forceps biopsy (EFB) and endoscopic submucosal dissection (ESD) in patients with early gastric neoplasm (EGN) exist objectively. Among them, pathological upgrading directly influences the accuracy and appropriateness of clinical decisions. The aims of this study were to investigate the risk factors for the discrepancies, with a particular focus on pathological upgrading and to establish a prediction model for estimating the risk of pathological upgrading after EFB.

Methods

We retrospectively collected the records of 978 patients who underwent ESD from December 1, 2017 to July 31, 2021 and who had a final histopathology determination of EGN. A nomogram to predict the risk of pathological upgrading was constructed after analyzing subgroup differences among the 901 lesions enrolled.

Results

The ratio of pathological upgrading was 510 of 953 (53.5%). Clinical, laboratorial and endoscopic characteristics were analyzed using univariable and binary multivariable logistic regression analyses. A nomogram was constructed by including age, history of chronic atrophic gastritis, symptoms of digestive system, blood high density lipoprotein concentration, macroscopic type, pathological diagnosis of EFB, uneven surface, remarkable redness, and lesion size. The C-statistics were 0.804 (95% confidence interval, 0.774 to 0.834) and 0.748 (95% confidence interval, 0.664 to 0.832) in the training and validation set, respectively. We also built an online webserver based on the proposed nomogram for convenient clinical use.

Conclusions

The clinical value of identifying the preoperative diagnosis of EGN lesions is limited when using EFB separately. We have developed a nomogram that can predict the probability of pathological upgrading with good calibration and discrimination value.

Clinical characteristics and risk factors for upgraded pathology in patients with gastric intraepithelial neoplasia after endoscopic submucosal dissection

BACKGROUND AND AIMS

The pathological results of endoscopic forceps biopsy (EFB) are frequently inconsistent with those after endoscopic submucosal dissection (ESD) in patients with gastric intraepithelial neoplasia (GIN). The aim of this study was to explore the risk factors for upgraded pathology after ESD in the Wannan region of Anhui Province, in order to guide the best clinical treatment of GIN.

METHODS

A retrospective analysis was performed at the First Affiliated Hospital of Wannan Medical College. Univariate analysis and multivariate analysis were used to investigate the independent risk factors for pathology upgrade between EFB and ESD.

RESULTS

In total, 215 patients who were initially diagnosed with GIN from EFB and subsequently received treatment with ESD were eventually selected for analysis. Age >60 years, a lesion located in upper 2/3 of the stomach, a lesion size of >2 cm, a lesion surface with redness and nodules and a lesion with irregular or absent microglands were significantly associated with the upgraded group after ESD. Multivariate analysis suggested that a lesion size of >2 cm (odds ratio [OR], 1.499; 95% confidence interval [CI], 1.222-1.909; P=0.026), a lesion surface with redness (OR, 1.508; 95%CI, 1.260-1.993; P=0.048) and nodules (OR, 1.390; 95%CI, 1.195-1.778; P=0.008) were independent predictors for the upgraded group.

CONCLUSIONS

For patients with suspected GIN by EFB, a lesion size of >2 cm, a lesion surface with redness and nodules should be taken into account before deciding on the ESD.

Endoscopic or Follow-up Treatment for Gastric Indeterminate Tumors Is the Preferred Method of Management

Background

Endoscopic forceps biopsy (EFB) lacks precision in diagnosing indeterminate tumors. When the presence of early gastric cancer (EGC) is macroscopically suspected, but biopsy pathology fails to give a diagnosis of neoplasia, it causes problems in clinical management. The purpose of this study was to discuss the outcome of gastric indeterminate tumors and the clinical factors associated with predicting EGC.

Methods

The medical records of 209 patients diagnosed with gastric indeterminate neoplasia by biopsy forceps were retrospectively studied. Initial endoscopic findings were analyzed and predictors of EGC were evaluated.

Results

The final pathological diagnosis in 209 patients included adenocarcinoma (n = 7), high-grade intraepithelial neoplasia (n = 11), low-grade intraepithelial neoplasia (n = 21), and non-neoplastic lesion (n = 170). Multivariate analysis showed that older age (OR = 1.78; 95% CI = 1.17–2.71; p = 0.008), patients undergoing narrow band imaging (NBI) (OR = 3.40; 95% CI = 1.37–8.43; p = 0.008), and surface erosion (OR = 3.53; 95% CI = 1.41–8.84; p = 0.007) were associated with the upgraded group, and were significantly associated with risk. Univariate logistic regression analysis showed that among patients with NBI, the presence of demarcation line (DL) (OR = 24.00; 95% CI = 4.99–115.36; p < 0.0001), microvascular (MV) pattern irregularity (OR = 9.129; 95% CI = 2.36–35.34; p = 0.001), and the presence of white opaque substance (WOS) (OR = 10.77; 95% CI = 1.14–101.72; p = 0.038) were significant risk factors.

Conclusions

For gastric indeterminate tumors, older patient age, lesion surface with erosion, clear DL visible under NBI observation, presence of WOS, and irregular MV pattern are suggestive of the high possibility of neoplasia and need to be focused on and may benefit more from endoscopic resection treatment as opposed to simple endoscopic follow-up.

Comparison of endoscopic treatments for small gastric adenomas

BACKGROUND

Gastric adenomas can be successfully treated with endoscopic resection, including endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR). The aim of this study was to evaluate and compare the efficacy of ESD and EMR with circumferential precutting (EMR-P) in the treatment of small gastric adenomas.

METHODS

This study included 1014 gastric adenomas ≤ 15 mm in diameter treated with ESD or EMR-P from 2012 to 2019, retrospectively. Propensity score matching between the ESD and EMR-P groups (1:1 to 3:1) was performed according to age, sex, tumor size, tumor location (upper, middle, and lower thirds), morphology, and preprocedural histology. The procedure time and the rates of en bloc resection, complete resection, adverse events, and local recurrence were compared between the two groups.

RESULTS

After propensity score matching, 478 lesions (ESD: 295, EMR-P: 183) were analyzed. The rates of en bloc resection (94.9% vs. 93.4%, p = 0.498), complete resection (93.6% vs. 90.2%, p = 0.177), bleeding (8.1% vs. 3.8%, p = 0.063), and local recurrence (0.0% vs. 1.4%, p = 0.185) did not significantly differ between the two groups. The procedure time was significantly longer for ESD than for EMR-P (p < 0.001). In the EMR-P group, the complete resection rate was significantly lower in the upper third than in the middle and lower thirds (p < 0.001).

CONCLUSION

EMR-P is as effective as ESD for the treatment of small gastric adenomas. However, the efficacy of EMR-P is lower for gastric adenomas in the proximal stomach.

Magnifying endoscopy with narrow-band imaging is useful in differentiating gastric cancer from matched adenoma in white light imaging

This study assessed the effect of magnifying endoscopy with narrow-band imaging (M-NBI) on the endoscopic differential diagnosis between intramucosal gastric carcinomas and adenomas with matched characteristics. Associations between magnified endoscopic findings and pathological high-grade cellular and architectural atypia were also investigated. In total, the records of 50 adenomas and 50 intramucosal well-differentiated adenocarcinomas matched by tumor size (≥ 20 mm or < 20 mm), shape (depression or non-depression), and color (red or non-red) were extracted. Fourteen endoscopists diagnosed adenoma or cancer in the 100 cases with conventional white light imaging (C-WLI), then did the same with C-WLI + M-NBI.The cancer diagnostic sensitivity, specificity, and accuracy were assessed. The sensitivity of C-WLI + M-NBI for cancer diagnosis was 79.9% compared to 71.6% with C-WLI (p < 0.001). There were no significant differences in specificity (40.1% vs. 36.3%, p = 0.296) and accuracy (55.9% vs. 58.1%, p = 0.163). High-grade cytological or architectural atypia was diagnosed more often with irregular microvascular pattern (IMVP) or microsurface pattern (IMSP), respectively, than the low-grade forms. In conclusion, IMVP and IMSP correlate with high-grade cytological and architectural atypia. M-NBI is useful in differentiating intramucosal carcinoma from adenoma and can reduce underdiagnosis of cancer.

Safety and efficacy of prophylactic gastric open peroral endoscopic myotomy for prevention of post-ESD stenosis: A case series (with video)

OBJECTIVE

Endoscopic resection of over 3/4 of the lumen of the antrum or pylorus is a known risk factor for post-endoscopic submucosal dissection (ESD) stenosis. Local or systemic steroids may reduce the risk of stenosis, but their overall role in stenosis prevention remains controversial. We aimed to evaluate the efficacy and safety of prophylactic gastric open peroral endoscopic myotomy (GO-POEM) in preventing post-ESD stenosis.

METHODS

Ten patients who underwent GO-POEM during or immediately after ESD in the Presbyterian Medical Center between June 2017 and November 2020 were included. All patients underwent excision of over 3/4 of the lumen of the antrum or pylorus. GO-POEM was performed without submucosal tunneling.

RESULTS

Well-differentiated tubular adenocarcinoma, tubulovillous adenoma with high-grade dysplasia, and tubular adenoma with low-grade dysplasia were diagnosed in three, one, and six patients, respectively. GO-POEM was performed successfully in all the 10 patients. Stenosis could not be evaluated in one patient, whereas one of the remaining nine patients developed post-ESD stenosis. GO-POEM decreased the risk of post-ESD stenosis in the other eight patients. Two patients presented with intraprocedural bleeding, both of whom were managed endoscopically successfully.

CONCLUSIONS

Prophylactic GO-POEM may be a novel, effective and safe treatment modality for preventing post-ESD stenosis in the stomach. Well-designed, multicenter studies with large sample sizes are needed to confirm our results.

Feasibility of gastric endoscopic submucosal dissection in elderly patients aged ≥ 80 years

BACKGROUND

Endoscopic resection, especially endoscopic submucosal dissection (ESD), is increasingly performed in elderly patients with early gastric cancer, and lesions beyond the expanded indications are also resected endoscopically in some patients. It is essential to assess whether gastric ESD is safe and suitable for elderly patients and investigate what type of lesions carry an increased risk of ESD-related complications.

AIM

To assess the efficacy and feasibility of gastric ESD for elderly patients, and define high-risk lesions and prognostic indicators.

METHODS

Among a total of 1169 sessions of gastric ESD performed in Kanagawa Cancer Center Hospital from 2006 to 2014, 179 sessions (15.3%) were performed in patients aged ≥ 80 years, and 172 of these sessions were done in patients with a final diagnosis of gastric cancer. These patients were studied retrospectively to evaluate short-term outcomes and survival. The short-term outcomes included the rates of en bloc resection and curative resection, complications, and procedure-related mortality. Curability was assessed according to the Japanese Gastric Cancer Treatment Guidelines 2010. Fisher’s exact test was used to statistically analyze risk factors. Clinical characteristics of each group were compared using Fisher’s exact test and Mann-Whitney U test. Survival rates at each time point were based on Kaplan-Meier estimation. Overall survival rates were compared between patients with gastric cancer in each group with use of the log-rank test. To identify prognostic factors that jointly predict the hazard of death while controlling for model overfitting, we used the least absolute shrinkage and selection operator (LASSO) Cox regression model including factors curative/ noncurative, age, gender, body mass index, prognostic nutritional index, Charlson comorbidity index (CCI), Glasgow prognostic score, neutrophil-to-lymphocyte ratio, and antithrombotic agent use. We selected the LASSO Cox regression model that resulted in minimal prediction error in 10-fold cross-validation. P < 0.05 was considered statistically significant.

RESULTS

The en bloc dissection rate was 97.1%, indicating that a high quality of treatment was achieved even in elderly patients. As for complications, the rates of bleeding, perforation and aspiration pneumonitis were 3.4%, 1.1% and 0.6%, respectively. These complication rates indicated that ESD was not associated with a particularly higher risk in elderly patients than in nonelderly patients. A dissection incision > 40 mm, lesions associated with depressions, and lesions with ulcers were risk factors for post-ESD bleeding, and location of the lesion in the upper third of the stomach was a risk factor for perforation in elderly patients (P < 0.05). Location of the lesion in the lower third of the stomach tended to be associated with a higher risk of bleeding. The overall survival (OS) did not differ significantly between curative and noncurative ESD (P = 0.69). In patients without additional surgery, OS rate was significantly lower in patients with a high CCI (≥ 2) than in those with a low CCI (≤ 1) (P < 0.001).

CONCLUSION

Gastric ESD is feasible even in patients aged ≥ 80 years. Observation without additional surgery after noncurative ESD is reasonable, especially in elderly patients with CCI ≥ 2.

Risk factors for the histologic discrepancy of gastric adenomatous lesions and long-term outcome

Although endoscopic forceps biopsies (EFB) have a significant role in diagnosing gastric adenoma, there are still discrepancies between EFBs and finalized pathology results.Therefore, the objective of this study was to find the risk factors that cause this discrepancy and to analyze the effects of this discrepancy on the long-term outcome.In this study patients that had received endoscopic resection due to low-grade gastric adenoma diagnosis from EFB between January of 2011 and January of 2018 at the Chungnam National University Hospital were retrospectively analyzed. According to whether there was histological discrepancy the cumulative incidence of the metachronous lesions were analyzed.A total of 745 lesions diagnosed as low-grade gastric adenoma at EFB were enrolled, and the final pathology results were confirmed to be non-neoplastic (n = 19), low-grade adenoma (n = 614), High-grade adenoma (n = 63), and carcinoma (n = 49), and with the exception of non-neoplastic lesion, the results confirmed 84.6% (n = 614) for the concordant group and 15.4% (n = 112) for the discordant. The results of the multivariate analysis confirmed that depressed lesion (odds ratio [OR]: 2.056; 95% confidence interval [CI]: 1.130-3.451; P = .011), erythema (OR: 2.546; 95% CI: 1.604-4.030; P = .004), and a size >1.5 cm (OR: 1.903; 95% CI: 1.102-3.172; P = .018) were risk factors for discrepancy. The results also confirmed that for the average observation period of (SD) 39.12 (12.31) months, the cumulative incidence of metachronous neoplasm had a higher significance (P = 0.001) in the discordant group when compared to that of the concordant group.The factors related to the histologic discrepancy of low-grade gastric adenoma were depressed lesion, erythema and size >1.5 cm. In the groups with histological discrepancy, the cumulative incidence of the metachronous neoplasm was significantly higher and therefore closer observation of such patients after performing endoscopic resection is necessary.

Endoscopic Resection for Gastric Subepithelial Tumor with Backup Laparoscopic Surgery: Description of a Single-Center Experience

The aim of this study was to analyze patients who underwent endoscopic resection (ER) for gastric subepithelial tumors (SETs) with a high probability of surgical intervention. Between January 2013 and January 2021, 83 patients underwent ER at the operation theater and 27 patients (32.5%) required backup surgery mainly due to incidental perforation or uncontrolled bleeding despite endoscopic repairing. The tumor was predominantly located in the upper-third stomach (81%) with a size ≤ 2 cm (69.9%) and deep to the muscularis propria (MP) layer (92.8%) but there were no significant differences between two groups except tumor exophytic growth as a risk factor in the surgery group (37% vs. 0%, p < 0.0001). Patients in the ER-only group had shorter durations of procedure times (60 min vs. 185 min, p < 0.0001) and lengths of stay (5 days vs. 7 days, p < 0.0001) but with a higher percentage of overall morbidity graded III (0% vs. 7.1%, p = 0.1571). After ER, five patients (6%) had delayed perforation and two (2.4%) required emergent laparoscopic surgery. Neither recurrence nor gastric stenosis was reported during long-term surveillance. Here, we provide a minimally invasive strategy of endoscopic resection with backup laparoscopic surgery for gastric SETs.

Clinical Outcomes of Endoscopic Resection for Low-Grade Dysplasia and High-Grade Dysplasia on Gastric Pretreatment Biopsy: Korea ESD Study Group

Background/Aims

Some cases of gastric low-grade dysplasia (LGD) and high-grade dysplasia (HGD) on forceps biopsy (FB) are diagnosed as gastric cancer (GC) after endoscopic resection (ER). This study aims to evaluate the clinical outcomes of ER for gastric LGD and HGD on pretreatment FB and to identify the factors that predict pathologic upstaging to GC.

Methods

Patients who underwent ER for LGD and HGD on pretreatment FB from March 2005 to February 2018 in 14 hospitals in South Korea were enrolled, and the patients’ medical records were reviewed retrospectively.

Results

This study included 2,150 cases of LGD and 1,534 cases of HGD diagnosed by pretreatment FB. In total, 589 of 2,150 LGDs (27.4%) were diagnosed as GC after ER. Helicobacterpylori infection, smoking history, tumor location in the lower third of the stomach, tumor size >10 mm, depressed lesion, and ulceration significantly predicted GC. A total of 1,115 out of 1,534 HGDs (72.7%) were diagnosed with GC after ER. Previous history of GC, H. pylori infection, smoking history, tumor location in the lower third of the stomach, tumor size >10 mm, depressed lesion, and ulceration were significantly associated with GC. As the number of risk factors predicting GC increased in both LGD and HGD on pretreatment FB, the rate of upstaging to GC after ER increased.

Conclusions

A substantial proportion of LGDs and HGDs on pretreatment FB were diagnosed as GC after ER. Accurate ER procedures such as endoscopic submucosal dissection should be recommended in cases of LGD and HGD with factors predicting pathologic upstaging to GC.

Differences between two sodium hyaluronate-based submucosal injection materials currently used in Japan based on viscosity analysis

In Japan, two 0.4% sodium hyaluronate (HA)-based submucosal injection materials (SIMs) are currently used in endoscopic submucosal dissection (ESD): MucoUp (HA-Mc) and Ksmart (HA-Ks). HA-Mc and HA-Ks have the same concentration and are, thus, construed by most endoscopists to have no difference. Nevertheless, visual observation conveys the impression that HA-Ks have a higher viscosity than HA-Mc, suggesting that HA-Ks performs better than HA-Mc. This study aimed to examine the differences between HA-Mc and HA-Ks. HA-Ks exhibited higher viscosity due to greater weight-average molecular weight compared with HA-Mc. HA-Ks had significantly greater submucosal elevation height (SEH) than HA-Mc; the SEH of HA-Ks-80% (80% dilution of HA-Ks) was the same as that of HA-Mc. The ESD procedure time was significantly shorter with HA-Ks than with HA-Mc (15.2 ± 4.1 vs. 19.5 ± 5.9; P = 0.049). The total injection volume for HA-Ks was significantly lower than that for HA-Mc (10.8 ± 3.6 vs. 14.4 ± 4.6; P = 0.045). However, no significant difference in these items was observed between HA-Mc and HA-Ks-80%. HA-Mc and HA-Ks were considered to be almost the same. Nonetheless, HA-Ks exhibited higher viscosity and SIM performance than HA-Mc. HA-Ks-80% had almost the same performance as HA-Mc. Thus, understanding SIM performance and characteristics requires a focus on the viscosity of SIMs.

Role of magnifying endoscopy with narrow-band imaging in the diagnosis of noninvasive gastric neoplasia

Background and Aim

There are no globally approved, distinguishing criteria enabling the classification of gastric adenomas and intramucosal carcinomas for differential diagnosis of noninvasive neoplasia (NIN).

Methods

Next‐generation sequencing of 50 cancer‐related genes was undertaken on 68 pathologically diagnosed microdissected gastric neoplasms (25 adenomas, 27 intramucosal carcinomas, and 16 submucosal carcinomas) obtained during endoscopic submucosal dissection. Findings from magnifying endoscopy with narrow‐band imaging (M‐NBI) of 52 NINs (the 25 adenomas and 27 intramucosal carcinomas) were compared with these data.

Results

Among all 68 neoplasms, the most frequently mutated genes were APC (76% in adenoma, 11.1% in intramucosal carcinoma, and 0% in submucosal carcinoma; P < 0.001) and TP53 in intramucosal and submucosal carcinomas (8% in adenoma, 48.1% in intramucosal carcinoma, and 75% in submucosal carcinoma; P < 0.001). Dividing the NIN neoplasms into five groups according to their mutational status (A1: APC mutation, A2: APC + α mutation, B: APC + TP53 mutation, C: TP53 mutation, D: no mutation in either APC or TP53) resulted in almost identical diagnoses by pathology and M‐NBI for groups A1 (12/13, 92%), C (12/13, 92%), and D (16/17, 94%) but not for groups A2 (3/7, 43%) or B (0/2, 0%). This finding implies that NINs with the APC + α mutation have carcinoma‐like endoscopic features despite most being judged as adenomas by pathology.

Conclusion

A diagnosis of NINs by pathology or M‐NBI in the subset of gastric tumors classified by cancer‐related mutations is not completely identical, suggesting the possible additional role of M‐NBI in diagnosing NINs. Further studies are needed to confirm this.

Early vs. Delayed Feeding after Endoscopic Submucosal Dissection for Gastric Cancer: A Systematic Review and Meta-Analysis

Background: Endoscopic submucosal dissection (ESD) for gastric cancer is increasingly performed worldwide due to its efficacy and safety. This study aimed to assess the evidence of the impact of early vs. delayed feeding after ESD on quality of care, which remains to be fully determined. Methods: Electronic databases (PubMed, the Cochrane Central Register of Controlled Trials, EMBASE) and the trial registries (the World Health Organization International Clinical Trials Platform Search Portal and ClinicalTrials.gov) were searched for studies performed prior to September 2020. Study selection, data abstraction, and quality assessment were independently performed using the Grading of Recommendations Assessment, Development, and Evaluation approach. Self-rated satisfaction and hospital stay were chiefly analyzed. Results: Two randomized controlled trials (239 patients) were included. The early and delayed post-ESD feeding groups had similar rates of post-ESD bleeding (risk ratio 1.90, 95% CI 0.42 to 8.63; I² = 0%). Early post-ESD feeding resulted in increased patients’ satisfaction in comparison to delayed post-ESD feeding (standard mean difference (MD) 0.54, 95% CI 0.27 to 0.81; I² = 0%) and reduced the length of hospital stay (MD −0.83, 95% CI −1.01 to −0.65; I² = 0%). Conclusion: Early post-ESD feeding was associated with increased patients’ satisfaction and reduced hospital stay in comparison to delayed feeding, while the rate of complications did not differ to a statistically significant extent. As we must acknowledge the limited number of reviewed studies, various trials regarding the quality of care are further needed to determine the benefits of early feeding after ESD.

Gastric cancer screening in low incidence populations: Position statement of AEG, SEED and SEAP

This positioning document, sponsored by the Asociación Española de Gastroenterología, the Sociedad Española de Endoscopia Digestiva and the Sociedad Española de Anatomía Patológica, aims to establish recommendations for the screening of gastric cancer (GC) in low incidence populations, such as the Spanish. To establish the quality of the evidence and the levels of recommendation, we used the methodology based on the GRADE system (Grading of Recommendations Assessment, Development and Evaluation). We obtained a consensus among experts using a Delphi method. The document evaluates screening in the general population, individuals with relatives with GC and subjects with GC precursor lesions (GCPL). The goal of the interventions should be to reduce GC related mortality. We recommend the use of the OLGIM classification and determine the intestinal metaplasia (IM) subtype in the evaluation of GCPL. We do not recommend to establish endoscopic mass screening for GC or Helicobacter pylori. However, the document strongly recommends to treat H.pylori if the infection is detected, and the investigation and treatment in individuals with a family history of GC or with GCPL. Instead, we recommend against the use of serological tests to detect GCPL. Endoscopic screening is suggested only in individuals that meet familial GC criteria. As for individuals with GCPL, endoscopic surveillance is only suggested in extensive IM associated with additional risk factors (incomplete IM and/or a family history of GC), after resection of dysplastic lesions or in patients with dysplasia without visible lesion after a high quality gastroscopy with chromoendoscopy.

The endoluminal pressures during flexible gastrointestinal endoscopy

In flexible gastrointestinal (GI) endoscopy, endoscopic insufflation is crucial and directly affects visualization. Optimal visualization enables endoscopists to conduct better examinations and administer optimal treatments. However, endoscopic insufflation is typically performed manually and is subjective. We aimed to measure the GI endoluminal pressure during flexible GI endoscopy. Participants underwent esophagogastroduodenoscopy (EGD) at our endoscopy center. Pressure measurement was conducted after completing diagnostic or follow-up EGD. The endoluminal pressure in the esophagus and stomach was measured at 1-s intervals for 1 min while performing EGD for observational and diagnostic purposes. During the measurements, the endoscopists maintained what they subjectively considered to be adequate exposure for screening for lesions by dilating the lumen. Eighty patients were enrolled in this study. The upper GI endoluminal pressure was assessed during EGD without adverse events. The esophageal endoluminal pressure averaged 8.9 (- 3.0 to 20.7) mmHg, and the gastric endoluminal pressure averaged 10.0 (3.0-17.9) mmHg; the upper GI endoluminal pressures were not affected by patient-related factors or the number of endoscopists' postgraduate years. We have successfully obtained the GI endoluminal pressures during EGD. Further accumulation of these data may lead to more stable and reproducible flexible endoscopic diagnosis and intervention.

Novel Pathologic Factors for Risk Stratification of Gastric "Indefinite for Dysplasia" Lesions

Methods

In total, 123 IND cases with final diagnoses of cancer (29.3%), high-grade dysplasia (6.5%), low-grade dysplasia (11.4%), and nonneoplasm (52.8%) were randomly divided into test set (n = 27) and validation set (n = 96). By the image analysis, size, pleomorphism, hyperchromasia, irregularity of nuclei, and ratios of structural atypia area (SAA) to total IND area were measured in the test set. Using the validation set, consensus meetings were held for the evaluation of pathologic factors that predict the final diagnosis.

Results

By image analysis, the only ratio of SAA to total IND area was associated with the final diagnosis (p < 0.001). In the consensus meeting for validation, the nuclear factors, except loss of nuclear polarity (p = 0.004–0.026), could not predict the final diagnosis. Conversely, most structural factors could predict the final diagnosis. In particular, SAA > 25% was the most powerful predictive factor. We proposed criteria of risk stratification by using SAA > 25%, loss of surface maturation (LOSM), and loss of nuclear polarity (LONP) (Malignancy rate; Category 0: SAA ≤ 25% without LOSM and LONP; 0%, Category 1: SAA ≤ 25% with any of LOSM or LONP; 15.2%–16.7%, Category 2: SAA > 25% without LOSM and LONP; 44.4%–50.0%, Category 3: SAA > 25% with any of LOSM or LONP 54.5%–55.6%).

Conclusions

Structural atypia was more helpful than nuclear atypia and SAA > 25% was the most powerful predictor for the diagnosis of INDs of the stomach. We propose shortening the follow-up period to six months for Category 1, endoscopic resection for Category 2 and 3, postresection follow-up periods of one year for Category 2, and six months for Category 3.

Predictors of technical difficulty with duodenal ESD

Background and study aims  Duodenal endoscopic submucosal dissection (ESD) is still considered technically challenging; however, few studies have objectively analyzed predictors of the technical difficulty. Therefore, the aim of the current study was to elucidate predictors of the technical difficulty of duodenal ESD. Patients and methods  This was a retrospective observational study. From June 2010 to June 2017, a total of 174 consecutive patients with superficial duodenal epithelial neoplasia who underwent ESD were included in this study. We tried to identify predictors for technical difficulty of ESD by defining technical difficulty as either procedure time > 100 minutes or intraprocedural perforation. Moreover, we constructed a scoring system consisting of factors that were significant in the multivariate analysis. Results  The proportion of patients with technical difficulty was 34.5 %. In the multivariate analysis, lesion location in flexural part [odds ratio (OR), 2.61; 95 % confidence interval (CI), 1.02 - 6.68], larger lesion size (> 40 mm) (OR, 5.26; 95% CI, 2.15 - 12.9), and occupied circumference > 50 % of the duodenum (OR, 5.80; 95 % CI, 1.83 - 18.4) were associated with technical difficulty. Conclusion  A lesion location in flexural part, lesion size >40 mm and occupied circumference > 50 % were risk factors for technical difficulty of duodenal ESD.

Management of adverse events related to endoscopic resection of upper gastrointestinal neoplasms: Review of the literature and recommendations from experts

Prevention therapy is recommended for lesions >1/2 of the esophageal circumference. Locoregional steroid injection is recommended for lesions >1/2-3/4 of the esophageal circumference and oral steroids are recommended for lesions >1/2 of the subtotal circumference. For lesions of the entire circumference, oral steroid combined with injection steroid is considered. Endoscopic balloon dilatation (EBD) is the first choice of treatment for stricture after esophageal endoscopic submucosal dissection (ESD). Radical incision and cutting or self-expandable metallic stent can be considered for refractory stricture after EBD. In case of intraoperative perforation during esophageal ESD, endoscopic clip closure should be initially attempted. Surgery is considered for treatment of delayed perforation. Current standard practice for prevention of delayed bleeding after gastric ESD includes prophylactic coagulation of vessels on post-ESD ulcers and giving proton pump inhibitors. Chronic kidney disease stage 4 or 5, multiple antithrombotic drug use, anticoagulant use, and heparin bridging therapy are high-risk factors for delayed bleeding after gastric ESD. Intraoperative perforation during gastric ESD is initially managed by endoscopic clip closure. If endoscopic clip closure is difficult, other methods such as over-the-scope clip (OTSC), polyglycolic acid (PGA) sheet shielding etc. are attempted. Delayed perforation usually requires surgical intervention, but endoscopic closure by OTSC or PGA sheet may be considered. Resection of three-quarters of the circumference is a risk factor for stenosis after gastric ESD. Giving prophylactic local steroid injection and/or oral steroid is reported, but effectiveness has not been fully verified as has been done for esophageal stricture. The main management method for gastric stenosis is EBD but it may cause perforation.

Clinical Implication and Risk Factors for Malignancy of Atypical Gastric Gland during Forceps Biopsy

Background/Aims

Although forceps biopsy is performed for suspicious gastric tumors during endoscopy, it is difficult to determine treatment strategies for atypical gastric glands due to uncertainty of the diagnosis. The aim of this study was to investigate clinical implications and risk factors for predicting malignancy in atypical gastric glands during forceps biopsy.

Methods

We retrospectively reviewed medical records of 252 patients with a diagnosis of atypical gastric gland during forceps biopsy. Predictors of malignancy were analyzed using initial endoscopic findings and clinical data.

Results

The final diagnosis for 252 consecutive patients was gastric cancer in 189 (75%), adenoma in 26 (10.3%), and gastritis in 37 (14.7%). In the multivariate analysis, lesion sizes of more than 10 mm (odds ratio [OR], 3.021; 95% confidence interval [CI], 1.480 to 6.165; p=0.002), depressed morphology (OR, 3.181; 95% CI, 1.579 to 6.406, p=0.001), and surface nodularity (OR, 3.432; 95% CI, 1.667 to 7.064, p=0.001) were significant risk factors for malignancy.

Conclusions

Further evaluation and treatment should be considered for atypical gastric gland during forceps biopsy if there is a large-sized (>10 mm) lesion, depressed morphology, or surface nodularity.

Endoscopic Indication of Endoscopic Submucosal Dissection for Early Gastric Cancer Is Not Compatible with Pathologic Criteria in Clinical Practice

BACKGROUND

The inappropriate selection of patients with early gastric cancer (EGC) for endoscopic submucosal dissection (ESD) may lead to additional surgery because of a non-curative resection. This study was performed to assess the accuracy of clinical decisions in ESD for EGC.

METHODS

A total of 607 cases of EGC treated by ESD were prospectively enrolled from January 2011 to June 2014 at a single academic hospital. The 607 EGCs were divided into three groups (overestimated, same-estimated, and underestimated) based on pre-procedure endoscopic findings (indication) and pathological diagnosis after ESD (criteria). We evaluated the discrepancy rates between pre-procedure indication and pathological criteria, and then analyzed the pre-procedure factors that could influence the occurrence of the discrepancies.

RESULTS

The absolute, expanded, and beyond the expanded indication has its accuracy on curability criteria in 87%, 77.6%, and 55.6% of cases, respectively. The ratio of overall indication-criteria discrepancies was 250/607 (41.2%). The curability was significantly lower in the underestimated group compared to the overestimated and same-estimated groups (41.6% vs. 94.6%, 94.4%, p < 0.001). In multivariate analysis examining the predictive factors for discrepancies in the 598 EGCs with absolute/expanded indications, the endoscopic size ≥ 20 mm [odds ratio (OR) 2.493, confidence interval (CI) 1.546-4.022, p < 0.001], presence of ulcers (OR 1.712, CI 1.070-2.738, p = 0.025), patient age < 60 years (OR 1.689, CI 1.044-2.733, p = 0.033), and undifferentiated type EGC on forceps biopsy (OR 5.397, CI 2.027-14.369, p = 0.001) were all associated with discrepancies.

CONCLUSIONS

Indication judged by pre-procedural endoscopy is not sufficiently accurate to be used as a good measurement for post-procedural criteria.

Endoscopic submucosal dissection of gastrointestinal lesions on an outpatient basis

Background

Endoscopic submucosal dissection (ESD) is usually associated with hospital admission.

Objectives

To evaluate, prospectively, the feasibility, safety and efficacy of outpatient gastrointestinal ESD.

Methods

Patients with suitable lesions were invited to participate. Those that dwelt more than 1 hour from the hospital, lived alone, had severe co-morbidities, were <18 years old, had duodenal lesions, or that had ESD-related complications were admitted. The remaining patients were discharged if no complications were detected. A patients' inquiry was performed.

Results

Of the 164 ESD patients, 122 were outpatient-based, corresponding to 115 patients, 47% male and mean age 63 ± 12 years-old. Outpatients tended to be younger, female, to have gastric lesions, less advanced lesions, and shorter and less complicated ESDs (all p < 0.05). Outpatients' mean tumour size was 38 mm, en bloc and R0 resection rates were 88 and 78%, respectively. Seven ESD outpatients (5.7%) had complications: delayed bleeding (n = 4), pneumonitis (n = 2) or emphysema (n = 1), all managed conservatively. Colorectal location of the lesions was predictive of hospital admission (p = 0.03). In total, 97% of patients were satisfied with the outpatient strategy.

Conclusion

Risks of ambulatory ESD are low and complications can be successfully managed. This strategy has high patient satisfaction. More studies are needed to evaluate its implications on costs and patients' management.

Clinical impact of closure of the mucosal defect after duodenal endoscopic submucosal dissection

BACKGROUND AND AIMS

Delayed adverse events (bleeding or perforation) are major concerns associated with duodenal endoscopic submucosal dissection (ESD). The aim of this study was to assess the efficacy of prophylactic closure of the mucosal defect after duodenal ESD.

METHODS

This is a retrospective study from a university hospital. One hundred sixty-eight patients (173 lesions) who underwent duodenal ESD between July 2010 and June 2017 were included in this study. The study participants were divided into 3 subgroups according to the degree of closure: complete group, incomplete group, and unclosed group. The proportion of delayed adverse events, maximum serum level of C-reactive protein (CRP), and total length of hospital stay were compared among these subgroups. Moreover, a multivariate logistic regression model was constructed to identify the risk factors for delayed adverse events.

RESULTS

The proportion of delayed adverse events in the complete group, incomplete group, and unclosed group were 1.7%, 25%, and 15.6%, respectively. The difference between the complete group and the other groups was significant (P < .01). The maximum serum CRP level was much lower (1.51 ± 2.18 mg/dL vs 6.28 ± 10.0 mg/dL, P < .01), and the length of hospital stay was significantly shorter in the complete group than in the incomplete/unclosed group (median [range] 5 [5-14] days vs 8 [4-59] days, P < .01). Multivariate analysis revealed that complete closure had a significant decrease in delayed adverse events (odds ratio [OR], 0.055; 95% confidence interval [CI], 0.01-0.29; P < .01), and a lesion located distal from the descending part showed a statistical tendency to an increase in delayed adverse events (OR, 4.48; 95% CI, 0.85-23.6; P = .08).

CONCLUSION

The present study revealed that complete closure of the mucosal defect after duodenal ESD significantly decreased the number of delayed adverse events and improved other outcomes.

Analysis of endoscopic features for histologic discrepancies between biopsy and endoscopic submucosal dissection in gastric neoplasms: 10-year results

BACKGROUND AND AIM

The histologic discrepancies between preoperative endoscopic forceps biopsy (EFB) and endoscopic submucosal dissection (ESD) specimens sometimes confuse the endoscope operator. This study aimed to analyze the limitation of the biopsy-based diagnosis before ESD and to evaluate which factors affect the discordant pathologic results between EFB and ESD.

METHODS

A total of 1427 patients, who were diagnosed with gastric adenoma by EFB, were enrolled. Cancer confirmed on EFB was excluded (n = 513). We retrospectively reviewed cases and compared histologic diagnoses in the biopsy sample with the final diagnosis in the endoscopically resected specimen.

RESULTS

The diagnosis was upgraded (from low-grade dysplasia to high-grade dysplasia or adenocarcinoma, or from high-grade dysplasia to adenocarcinoma) in 328 cases (23.0%), concordant in 944 (66.1%), and downgraded (from high-grade dysplasia to low-grade dysplasia or non-neoplasia, or from low-grade dysplasia to non-neoplasia) in 155 (10.9%). Multivariate logistic regression analysis showed that surface ulceration and depressed lesions were associated with significant risk factors for upgrading. Age younger than 60 years and size <1 cm were associated with significant factors for downgrading.

CONCLUSIONS

Careful endoscopic observation should consider size, ulceration, and depression to ensure accurate diagnosis when a gastric neoplasm is suspected.

Outcomes of endoscopic resection for superficial duodenal epithelial neoplasia

BACKGROUND AND AIMS

Pancreaticoduodenectomy is an invasive procedure, and endoscopic resection (ER) is an alternative therapy. However, details regarding the outcomes of ER are unknown, especially for superficial duodenal epithelial neoplasia (SDET). The aim of this study was to elucidate the outcomes of ER for SDET and to compare EMR with endoscopic submucosal dissection (ESD).

METHODS

This was a retrospective observational study. From June 2010 to June 2017, 320 cases of endoscopically resected SDET (146 EMR-treated cases and 174 ESD-treated cases) were included in this study. We analyzed the proportions of en bloc resection, R0 resection, perforation, and bleeding as outcomes of ER and compared outcomes between the EMR and ESD groups. Next, we collected data on the features and clinical course of cases with adverse events.

RESULTS

The proportions of en bloc resection and R0 resection among all cases were 96.6% and 83.4%, respectively. In over 95% of cases, ESD achieved en bloc resection, regardless of lesion size. The incidences of perforation and bleeding were 8.8% and 3.4%, respectively, and the former was largely successfully managed by conservative treatment. The mortality rate was 0%, and all patients were discharged with a median hospital stay of 8.5 days (range, 4-52 days). Evaluation of the hospital stay duration according to lesion circumference revealed a significantly longer duration for lesions present on the medial wall than for other lesions (median 41 vs 7 days, P = .0331).

CONCLUSION

The present study revealed that ER achieved secure en bloc resection, with the treatment type (ESD or EMR) selected according to the lesion size. A lesion located on the medial wall was associated with worse outcomes, such as prolonged hospital stay after perforation.

Pathologic outcomes of endoscopic submucosal dissection for gastric epithelial neoplasia

Endoscopic submucosal dissection (ESD) has been widely implemented for the treatment of gastric superficial neoplasia. However, the final pathologic diagnosis after ESD may be different from that indicated by the results of endoscopic forceps biopsy. This study identified risk factors for gastric epithelial lesions so that early gastric cancer (EGC) could be diagnosed after ESD.From December 2008 to January 2017, 1541 lesions (1410 patients) diagnosed as initial adenoma or indefinite for neoplasia by endoscopic forceps biopsy were enrolled. The EGC rate and factors predicting upstaged diagnoses were analyzed retrospectively.The diagnostic discrepancy rate was 31.1%. Upstaged and downstaged diagnostic rates after ESD were 23.8% and 7.3%, respectively. The upstaged diagnosis rate for EGC was 18.8%. Gross depression (OR, 16.017) and surface redness (OR, 22.136) were significantly associated with EGC and lesions indefinite for neoplasia during the initial endoscopic forceps biopsy. Central depression (OR, 2.959), nodular surface (OR, 6.581), and surface redness (OR, 6.399) were significantly associated with EGC and lesions with low-grade dysplasia during the initial endoscopic forceps biopsy. Central depression (OR, 1.999), nodular surface (OR, 1.733), surface redness (OR 2.283), lesion location (upper third of the stomach) (OR, 3.989), and tumor size ≥10 mm (OR, 2.200) were significantly associated with EGC and lesions with high-grade dysplasia during the initial endoscopic forceps biopsy.Central depression, nodular surface, surface redness, lesion location, and tumors >10 mm were associated with EGC. Gastric epithelial lesions with these characteristics require attention before ESD.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Gastric Cancer Caused by Adenoma: Predictive Factors Associated with Lesions Other Than the Expanded Indications

Background/Aims

We aimed to investigate whether the current indications for curative endoscopic resection (ER) of gastric cancer (GC) can be applied to GC caused by adenoma. Additionally, we attempted to identify factors predictive of lesions subsequently found in addition to the expanded indications for ER.

Methods

We retrospectively analyzed 342 patients diagnosed with GC caused by adenoma who underwent ER at a single tertiary center between February 2011 and December 2014. The gross whole tumor size was measured using the endoscopically resected specimen. The microscopic whole tumor size was measured using mapping paper. The estimated cancer size was calculated using the microscopic whole tumor size and the square root of the carcinoma component.

Results

A gross whole tumor size ≥3 cm, carcinoma component ≥35%, and gross ulceration were predictive of lesions other than the expanded indications for ER. The overall rate of lymph node metastasis was 0.3% (1/327), which only occurred in one patient with a lesion other than the expanded indications (4.5%, 1/22).

Conclusions

The current indications for curative ER in GC can be applied to GC caused by adenoma. In cases suspected of having lesions other than the expanded indications, patients should be cautiously selected for ER to reduce the risk of an inappropriate procedure.

Incidence of gastric adenocarcinoma among lesions diagnosed as low-grade adenoma/dysplasia on endoscopic biopsy: A multicenter, prospective, observational study

BACKGROUND AND AIM

Differentiation between gastric adenocarcinoma and low-grade adenoma/dysplasia (LGA) on endoscopic forceps biopsy is difficult. We aim to clarify the incidence of carcinoma in specimens, obtained by endoscopic resection (ER), from cases that had been diagnosed as LGA (Vienna category 3) on endoscopic biopsy.

METHODS

In this multicenter, prospective, observational study, patients with gastric adenoma (Vienna category 3 or 4.1) diagnosed on endoscopic forceps biopsy were enrolled. All the specimens were subjected to histopathological central review. Primary endpoint was the incidence of carcinoma (Vienna category 4.2 or over) among the biopsy-proven gastric LGA. Secondary endpoints were the histological findings of resected specimens, clinicopathological features of carcinoma, and short-term outcomes of all ER cases.

RESULTS

Ninety-five patients with 104 lesions diagnosed as gastric adenoma were enrolled. After central review of the biopsy specimens, 47 lesions were diagnosed as LGA and seven lesions (15%) as adenocarcinoma (95% confidence interval, 7.6-28%). Carcinoma was detected in lesions that had a minimum size of 6 mm; the incidence of carcinoma was higher in the larger lesions. There was a histological discrepancy between biopsy and ER material in more than 60% of the cases.

CONCLUSIONS

A substantial proportion of biopsy-proven gastric LGA specimens were diagnosed as adenocarcinoma after ER. This indicated histological discrepancy between biopsy-proven gastric LGA and histology of the resected material.

Helicobacter pylori management in ASEAN: The Bangkok consensus report

Helicobacter pylori (H. pylori) infection remains to be the major cause of important upper gastrointestinal diseases such as chronic gastritis, peptic ulcer, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. H. pylori management in ASEAN: the Bangkok consensus report gathered key opinion leaders for the region to review and evaluate clinical aspects of H. pylori infection and to develop consensus statements, rationales, and grades of recommendation for the management of H. pylori infection in clinical practice in ASEAN countries. This ASEAN Consensus consisted of 34 international experts from 10 ASEAN countries, Japan, Taiwan, and the United States. The meeting mainly focused on four issues: (i) epidemiology and disease association; (ii) diagnostic tests; (iii) management; and (iv) follow-up after eradication. The final results of each workshop were presented for consensus voting by all participants. Statements, rationale, and recommendations were developed from the available current evidence to help clinicians in the diagnosis and treatment of H. pylori and its clinical diseases.

[Endoscopic Treatment of Gastric Adenoma]

Gastric adenoma (dysplasia) is a precancerous lesion. Therefore, managements of gastric adenomas are important for preventing the development of gastric cancers and for detecting gastric cancers at earlier stages. The Vienna classification divides gastric adenomas into two categories: high-grade dysplasia and low-grade dysplasia. Generally, endoscopic resection is performed for adenoma with high-grade dysplasia due to the coexistence of carcinoma and the potential of progression to carcinomas. However, the treatments of adenoma with low-grade dysplasia remain controversial. Currently two treatment strategies for the low-grade type have been suggested; First is the 'wait and see' strategy; Second is endoscopic treatment (e.g., endoscopic mucosal resection, endoscopic submucosal dissection, or argon plasma coagulation). In this review, we discuss the current optimal strategies for endoscopic management of gastric adenoma.

The serum pepsinogen levels for risk assessment of gastric neoplasms: New proposal from a case-control study in Korea

To decrease the gastric cancer related mortality rate, endoscopic screening is widely performed in Korea. However, a precise method for identifying those at a high risk of gastric neoplasms has not been established. This study aims to evaluate serum pepsinogen (PG) levels for risk assessment of gastric neoplasms. Between August 2014 and March 2016, a total of 398 subjects, including 87 with gastric neoplasms, were enrolled in this study. On the basis of the serum PG I/II ratio, the enrolled subjects were classified into 4 groups: group A, PG I/II ratio >4; group B, >3 and ≤4; group C, >2 and ≤3; group D, ≤2. Compared with group A, a stepwise increase in the risk of gastric neoplasm was observed from group B [odds ratio (OR) = 9.9, 95% confidence interval (95% CI) = 4.0-24.4] to group C (OR = 20.9, 95% CI = 8.7-50.5) to group D (OR = 37.3, 95% CI = 14.3-97.4). The optimal cutoff value of the serum PG I/II ratio for predicting gastric neoplasms was 4.5, with a sensitivity of 97.7% and a specificity of 57.6%. A decrease in the serum PG I/II ratio was strongly associated with an increased risk of gastric neoplasms. The serum PG I/II ratio can be used to identify those at a high risk of gastric neoplasms in Korean population.

Risk Factors for Additional Surgery after Iatrogenic Perforations due to Endoscopic Submucosal Dissection

Objectives. Endoscopic resection (ER) is commonly performed to treat gastric epithelial neoplasms and subepithelial tumors. The aim of this study was to predict the risk factors for surgery after ER-induced perforation. Methods. We retrospectively reviewed the data on patients who received gastric endoscopic submucosal dissection (ESD) or endoscopic mucosal resection (EMR) between January 2010 and March 2015. Patients who were confirmed to have perforation were classified into surgery and nonsurgery groups. We aimed to determine the risk factors for surgery in patients who developed iatrogenic gastric perforations. Results. A total of 1183 patients underwent ER. Perforation occurred in 69 (5.8%) patients, and 9 patients (0.8%) required surgery to manage the perforation. In univariate analysis, anterior location of the lesion, a subepithelial lesion, two or more postprocedure pain killers within 24 hrs, and increased heart rate within 24 hrs after the procedure were the factors related to surgery. In logistic regression analysis, the location of the lesion at the anterior wall and using two or more postprocedure pain killers within 24 hrs were risk factors for surgery. Conclusion. Most cases of perforations after ER can be managed conservatively. When a patient requires two or more postprocedure pain killers within 24 hrs and the lesion is located on the anterior wall, early surgery should be considered instead of conservative management.

The importance of the concept and histological criteria of "intraepithelial squamous cell carcinoma" of the esophagus: in comparison between Western and Japanese criteria

BACKGROUND

There are differences in the histological diagnostic criteria for early stage gastrointestinal carcinoma between Western and Japanese pathologists. Western histological criteria of carcinoma are "presence of stromal invasion of neoplastic cells", while Japanese criteria are "the degree of cytological and structural abnormality of neoplastic cells, regardless of stromal invasion". The aim of the present study is to clarify and review the present status of the Western and Japanese histological criteria of early stage esophageal squamous cell carcinoma (SCC) and also to clarify their significance and accuracy.

METHODS

Twenty-nine Polish, German, and Japanese pathologists participated in this study. A total of 18 histological slides of biopsy, endoscopic submucosal dissection (ESD), and surgical resection of esophageal squamous lesions were diagnosed using a virtual slide system.

RESULTS

Most of noninvasive (intraepithelial) carcinomas diagnosed by Japanese pathologists were diagnosed as high- or low-grade dysplasia (intraepithelial neoplasia) or reactive atypia by the majority of Polish and German pathologists. Diagnoses of not only high-grade dysplasia but also low-grade dysplasia or reactive lesion by Western criteria were given for many biopsy specimens of cases in which the corresponding ESD or surgical specimens showed definite stromal invasion.

CONCLUSION

There still exist differences in the histological diagnostic criteria for early stage esophageal carcinoma between Western and Japanese pathologists. The Japanese diagnostic criteria could improve agreement of diagnoses between biopsy and resected specimens of esophageal SCC. Moreover, diagnostic approaches using Western criteria may cause delay in the early diagnosis and treatment of esophageal SCC.

Clinical Factors of Delayed Perforation after Endoscopic Submucosal Dissection for Gastric Neoplasms

BACKGROUND

Delayed perforation is a rare but severe complication of endoscopic submucosal dissection (ESD) for early gastric neoplasm (EGN). The aim of this study was to clarify clinical factors related to delayed perforation after ESD.

METHODS

A total of 1158 consecutive patients with 1199 EGNs underwent ESD at our hospital between January 2000 and December 2015. Univariate analysis was used to identify clinicopathological factors related to delayed perforation. Moreover, duration of cautery needed for hemostasis was measured by comparison between perforated and nonperforated points in patients with delayed perforation.

RESULTS

Delayed perforation occurred in 5 of 1158 consecutive patients with 1199 EGNs who underwent ESD (0.42%). All cases were diagnosed within 24 h after ESD and recovered with conservative management. On univariate analysis, location in the upper stomach was the factor most significantly associated with delayed perforation (P < 0.01). Duration of cautery needed for hemostasis was significantly longer at perforated points (9 s) than at nonperforated points (3.5 s) in five patients.

CONCLUSIONS

Location in the upper stomach was the risk factor most prominently associated with delayed perforation after ESD for EGNs. In addition, delayed perforation appears associated with excessive electrocautery for hemostasis.

Clinical outcomes of endoscopic submucosa dissection for high-grade dysplasia from endoscopic forceps biopsy

BACKGROUND AND STUDY AIMS

Although the Vienna Classification recommends endoscopic resection for gastric high-grade dysplasia (HGD), many resected lesions are diagnosed as gastric cancer after endoscopic resection. This study aims to evaluate the clinical outcomes of gastric HGD identified by endoscopic forceps biopsy (EFB) after endoscopic submucosal dissection (ESD) and factors associated with discrepant results.

PATIENTS AND METHODS

From December 2008 to July 2015, a total of 427 lesions diagnosed as initial HGD by EFB were enrolled. The rate of early gastric cancer (EGC) and factors predicting diagnosis upgrade were analyzed retrospectively.

RESULTS

Tumors ranged between 2 and 65 mm in size (median 12.59). En bloc and complete resection rates were 97.4 and 95.3%, respectively. The diagnostic discrepancy rate was 76.3%. Upgrade and downgrade rates of pathological diagnoses were 66.5 and 9.8%, respectively. Central depression (OR 4.151), nodular surface (OR 5.582), surface redness (OR 2.926), lesion location (upper third of the stomach) (OR 3.894), and tumor size ≥10 mm (OR 2.287) were significantly associated with EGC. Nodular surface (OR 2.746), submucosal fibrosis (OR 3.958), lesion location (upper third of the stomach) (OR 6.652), and tumor size ≥10 mm (OR 4.935) significantly predicted invasive submucosal cancer.

CONCLUSIONS

Central depression, nodular surface, surface redness, lesion location, large tumor size, and submucosal fibrosis were associated with EGC or submucosal cancer. Caution must be used in treating lesions with these features with ESD.

Endoscopic management of mucosal lesions in the gastrointestinal tract

With the increasing role of endoscopy in patient evaluation, more mucosal lesions, including gastric, duodenal and colonic polyps, are encountered during routine examinations. It is imperative for gastroenterologists to become familiar with the endoscopic management of these various gastrointestinal lesions. In this article, various resection techniques will be discussed, including hot/cold forceps polypectomy, hot/cold snare polypectomy, endoscopic mucosal resection, and endoscopic submucosal dissection. The article will also discuss the evidence regarding the efficacy and safety of these techniques and the future direction of endoscopic management of mucosal lesions in the gastrointestinal tract.

Expression of microRNA-328 Functions as a Biomarker for Recurrence of Early Gastric Cancer (EGC) After Endoscopic Submucosal Dissection (ESD) by Modulating CD44

Background

This study investigated the molecular mechanism of the effect of CD44 on the recurrence of EGC after ESD, including the potential regulator and signaling pathways of CD44.

Material/Methods

We searched the miRNA online database (www.mirdb.org) with the “seed sequence” located within the 3′-UTR of the target gene, and performed luciferase assay to test the miRNA/mRNA relationship. We also determined the expression of CD44 in the EGC and control samples. In addition, statistical analysis was used to explore the role of miR-328 as a biomarker to predict the recurrence after ECD.

Results

We validated CD44 to be the direct gene via luciferase reporter assay system. We also established the negative regulatory relationship between miR-328 and CD44 via studying the relative luciferase activity at different concentrations of miR-328 mimics. We also conducted real-time PCR and Western blot analysis to study the mRNA and protein expression level of CD44 among different groups (recurrence-positive and recurrence-negative) or cells treated with different concentrations of miR-328 mimics/inhibitors, indicating the negative regulatory relationship between miR-328 and CD44. We also investigated the relative viability of EGC cells when transfected with miR-328 mimics (50 nM and 100 nM) and miR-328 inhibitors (100 nM) to validate miR-328 to be negatively interfering with the viability of EGC cells. miR-328 was also recognized as a potential biomarker to predict recurrence after ESD in EGC patients via analysis of the recurrence-free rate among different groups of EGC patients.

Conclusions

The expression level of miR-328 can function as a predictive biomarker of recurrence after ECD in patients with EGC via targeting CD44.

Helicobacter pylori-negative intestinal-type gastric adenoma successfully treated by endoscopic submucosal dissection: a case report

A 49-year-old woman underwent an esophagogastroduodenoscopy as part of a health check at our hospital. Endoscopic observation revealed a flat elevated lesion 6 mm in diameter in the gastric antrum (Paris Classification type IIa). Magnifying endoscopy using narrow-band imaging showed a slightly irregular micro-surface pattern with round and oval pits, as well as a regular micro-vascular pattern without a demarcation line. Atrophy and intestinal metaplasia were not recognized in the background gastric mucosa. Furthermore, Helicobacter pylori infection was not detected by histologic, serologic, and urea breath test results. Endoscopic resection was performed for histologic evaluation, and a pathologic diagnosis of intestinal-type gastric adenoma occurring in pyloric mucosa without atrophy or metaplasia was established. Immunohistochemistry findings of the lesion showed the intestinal epithelium phenotype with positive staining for MUC2, CD10, and CDX2. Furthermore, irregular distribution with a higher positive proportion of Ki-67 was found in the lesion, indicating its malignant potential. We report here a rare case of gastric adenoma without surrounding intestinal metaplasia occurring in a Helicobacter pylori-negative patient.

Clinical features of negative pathologic results after gastric endoscopic submucosal dissection

BACKGROUND

Endoscopic submucosal dissection (ESD) is widely used for the treatment of gastric superficial neoplasms. Negative pathologic results after ESD can confuse the endoscopists and patients. The aim of this study was to evaluate the reasons for and the factors associated with negative pathologic results after ESD.

PATIENTS AND METHODS

From December 2008 to July 2015, a total of 1379 lesions diagnosed as definite dysplasia or adenocarcinoma by endoscopic forceps biopsy (EFB) were removed with an ESD procedure. The initial endoscopic and pathologic findings were analyzed.

RESULTS

The incidence of negative pathology after ESD was 2.0 % (28/1379). Compared with positive pathologic lesions, negative pathologic lesions were smaller and had less surface area (P < 0.001). The reasons for negative pathologic lesions after ESD were complete removal by EFB (n = 20), over-estimations of the EFB specimen (n = 5), and different ESD site (n = 3).

CONCLUSION

Small tumor size and surface area are associated with negative pathologic results after ESD. When negative pathologic results are reported after ESD, we should review the previous endoscopic biopsy tissue specimen and compare the previous EFB site to the ESD site. Thereafter, regular endoscopic examination of the lesion is needed.

Retrospective study: The diagnostic accuracy of conventional forceps biopsy of gastric epithelial compared to endoscopic submucosal dissection (STROBE compliant)

Conventional forceps biopsy (CFB) is the most popular way to screen for gastric epithelial neoplasia (GEN) and adenocarcinoma of gastric epithelium. The aim of this study was to compare the diagnostic accuracy between conventional forceps biopsy and endoscopic submucosal dissection (ESD).Four hundred forty-four patients who finally undertook ESD in our hospital were enrolled from Jan 1, 2009 to Sep 1, 2015. We retrospectively assessed the characteristics of pathological results of CFB and ESD.The concordance rate between CFB and ESD specimens was 68.92% (306/444). Men showed a lower concordance rate (63.61% vs 79.33%; P = 0.001) and concordance patients were younger (P = 0.048). In multivariate analysis, men significantly had a lower concordance rate (coefficient -0.730, P = 0.002) and a higher rate of pathological upgrade (coefficient -0.648, P = 0.015). Locations of CFB did not influence the concordance rate statistically.The concordance rate was relatively high in our hospital. According to our analysis, old men plus gastric fundus or antrum of CFB were strongly suggested to perform ESD if precancerous lesions were found. And young women with low-grade intraepithelial neoplasia could select regular follow-up.