Meticulous lymph node 6 station (LN#6) dissection is mandatory in pylorus-preserving gastrectomy (PPG), but can increase the risk of complications, such as postoperative delayed gastric emptying. With analyzing lymphatic spread patterns based on cross-sectional tumor location, we planned to predict the surgical burden of LN#6 dissection, balancing oncological safety and risk of postoperative complications.

We included consecutive PPG cases at Seoul National University Hospital (2007-2017) to assess the incidence, 5-year survival rate (5YSR), and 3-year recurrence-free survival (3RFS) of LN#6 metastasis. Cox regression analyzed the impact of LN#6 metastasis itself on 5YSR and 3RFS. The effect of tumor location among gastric middle-third tumors on LN#6 metastasis was evaluated. The therapeutic indices (TI) of LN#6 based on tumor location were calculated.

Among 1070 PPG patients, 5YSR and 3RFS were 97.0% and 98.9%. LN#6 metastasis was found in 11 patients (1.03%), with 3 recurrences observed among them (3/11, 0.28%). LN#6 metastasis itself did not significantly affect 5YSR (p = 0.266) or 3RFS (p = 0.075). Tumor location showed a significant association for LN#6 metastasis (p = 0.015), with low body greater curvature (LB-GC) showing the highest prevalence (5/11, 45.45%). TI of LN#6 for LB-GC tumors was 3.76, while TI for low body lesser curvature (LB-LC) and midbody lesser curvature (MB-LC) tumors was 0.0.

LN#6 metastasis is infrequent and does not affect 5YSR or 3RFS in PPG patients. Tumors in LB-GC demonstrated a higher tendency for lymphatic spread to LN#6, while those in lesser curvature demonstrated a lower spread, suggesting a reduced surgical burden for lesser curvature tumors. This study evaluated LN#6 metastasis in 1070 PPG patients, demonstrating low incidence and favorable oncological outcomes, supporting tailored LN#6 dissection for lesser curvature tumors to minimize complications without compromising safety.

Endoscopic submucosal dissection (ESD) is a minimally invasive treatment for early gastric cancer; additional treatment may be recommended for patients in whom resection is not curative per the American Society for Gastrointestinal Endoscopy guidelines. The aim of this study was to assess treatment outcomes of ESD for gastric neoplasia, with a focus on cases of non-curative resection.

This was a retrospective study of all individuals undergoing ESD for the treatment of gastric adenocarcinoma or dysplasia in a high-volume tertiary care center in the United States. Data on patient demographic characteristics, clinical history, lesion characteristics, and procedural and clinical outcomes were collected from the electronic medical record.

Among 82 cases undergoing ESD for the management of gastric neoplasia, 32 cases resulted in non-curative resection. 20 of these non-curative cases did not get additional treatment, among which recurrence occurred in two cases with positive horizontal margins only. These patients did not show lymph node metastasis and underwent further endoscopic or surgical resection. There was no recurrence in 11 cases with undifferentiated carcinomas of ≤2 cm in size.

Although this study was limited by its retrospective design, small sample size, and follow-up duration, our findings suggest that a risk-adapted strategy could be employed for certain patients undergoing non-curative ESD per American Society for Gastrointestinal Endoscopy guidelines, with close follow-up instead of routine surgery in select cases with favorable features. Further studies are needed to refine the criteria for additional treatment after non-curative ESD in Western populations.

The novel curability criteria for elderly (EL) patients have been proposed to stratify their risk of lymph node metastasis (LNM), following non-curative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). Hence, this study aimed to evaluate the effectiveness of the EL criteria and compare them with those of the well-known eCura system.

A retrospective analysis was performed on 143 patients who did not meet the curative ESD criteria at a tertiary hospital in Korea between 2011 and 2022. Of these, 102 underwent additional surgery, while 41 were followed up without further treatment. The LNM rates based on the EL and eCura systems were stratified and compared.

In the surgery group, 29.4% (30/102) patients were classified as EL-low (EL-L) and 70.2% (72/102) as EL-high (EL-H). The LNM rates (95% confidence interval) were 0.0% (0.0-11.6) and 9.7% (4.0-19.0) for EL-L and EL-H, respectively (P=0.102). EL-L was closely aligned with the eCura low-risk category, with a similar patient proportion (32.4%) and an LNM rate of 0.0% (0.0-10.6). The eCura system classified 94.1% (48/51) of the EL-L patients as low-risk, with an 86% concordance rate (123/143). Discordant cases included patients with positive vertical margins, but without other risk factors, who were classified as EL-H without LNM.

Patients with EL-L showed no LNM, and the EL criteria demonstrated high concordance with the eCura system. The EL criteria may be as effective as the eCura system in identifying low-risk patients after non-curative ESD for EGC.

A newly developed articulated through-the-scope traction device, TRACMOTION, has been used clinically for endoscopic submucosal dissection (ESD). However, there are few reports on the characteristics of this device and the lesion types for which it is most effective. Therefore, we evaluated its optimal use, efficacy, and safety clinically in animals. Subsequently, we confirmed the safety and efficacy of ESD using this device in humans. Two live swine were used; one underwent conventional ESD (C-ESD) and the other traction-assisted ESD (T-ESD). To examine the traction effect at each resection site, three ESD ulcers (greater curvature/anterior wall/posterior wall) with a diameter of approximately 40 mm were created in each swine. Based on our preliminary experiments, scissor-type and needle-type knives were used in the T-ESD and C-ESD groups, respectively. The primary endpoint was the resection speed, and the secondary endpoint was the degree of muscle layer damage. T-ESD was faster than C-ESD on the posterior wall, similar to the greater curvature, and T-ESD was slower than C-ESD on the anterior wall. There were no cases of intraoperative perforations. Obvious muscle layer damage was observed in post-C-ESD wounds on the anterior wall. The submucosal layer was retained in all post-T-ESD wounds. Although this study showed that ESD with TRACMOTION may be safe and effective, it is necessary to consider that it may be unsuitable for some lesions. This may be due to device characteristics and requires further validation.

Recent advances in endoscopic equipment have improved the diagnosis of gastrointestinal tumors. Image-enhanced endoscopy, including narrow-band imaging, blue light imaging, and linked color imaging, has unified magnifying observation classification methods and significantly improved the qualitative and quantitative diagnostic performance of gastrointestinal epithelial tumors. Endoscopic submucosal dissection (ESD), a minimally invasive treatment for early-stage gastrointestinal cancer, is widely used. The aging population in Japan has been gradually increasing. Despite this, ESD has shown good outcomes in older adults. However, long-term prognostic analyses should take into account the high mortality rate from other illnesses. Prognostic indicators such as the Charlson Comorbidity Index (CCI) and the Prognostic Nutrition Index (PNI) should be used to determine whether ESD should be performed. Even in cases of noncurative resection, follow-up without additional surgical resection is an option if there are other comorbidities that affect the prognosis.

Objectives: The accurate prediction of lymph node metastasis (LNM) and lymphovascular invasion (LVI) is crucial for determining treatment strategies for early gastric cancer (EGC). This study aimed to develop and validate a deep learning-based clinical decision support system (CDSS) to predict LNM including LVI in EGC using real-world data. Methods: A deep learning-based CDSS was developed by integrating endoscopic images, demographic data, biopsy pathology, and CT findings from the data of 2927 patients with EGC across five institutions. We compared a transformer-based model to an image-only (basic convolutional neural network (CNN)) model and a multimodal classification (CNN with random forest) model. Internal testing was conducted on 449 patients from the five institutions, and external validation was performed on 766 patients from two other institutions. Model performance was assessed using the area under the receiver operating characteristic curve (AUC), probability density function, and clinical utility curve. Results: In the training, internal, and external validation cohorts, LNM/LVI was observed in 379 (12.95%), 49 (10.91%), 15 (9.09%), and 41 (6.82%) patients, respectively. The transformer-based model achieved an AUC of 0.9083, sensitivity of 85.71%, and specificity of 90.75%, outperforming the CNN (AUC 0.5937) and CNN with random forest (AUC 0.7548). High sensitivity and specificity were maintained in internal and external validations. The transformer model distinguished 91.8% of patients with LNM in the internal validation dataset, and 94.0% and 89.1% in the two different external datasets. Conclusions: We propose a deep learning-based CDSS for predicting LNM/LVI in EGC by integrating real-world data, potentially guiding treatment strategies in clinical settings.

The treatment of early gastric cancer (EGC) is contingent upon the status of lymph node metastasis (LNM). Accurate preoperative prediction of LNM is critical for reducing unnecessary surgeries. This study seeks to evaluate the risk factors for LNM in submucosal EGC and develop a predictive model to optimize therapeutic decision-making.

A retrospective analysis was performed on clinical data from 389 patients with T1b-stage EGC who underwent radical gastrectomy. Univariate and multivariate analyses were conducted to identify independent risk factors, followed by the development of a nomogram to predict LNM. The model's efficacy was validated through receiver operating characteristic curves, calibration curves, and decision curve analysis.

Of the 389 patients, 77 had LNM. Logistic regression analysis identified gender, CA199 levels, tumor location, degree of differentiation, presence of ulcers, and lymph node enlargement on CT as independent risk factors for LNM. A nomogram was constructed to assess the risk of LNM, demonstrating strong predictive accuracy with an area under the curve of 0.82 in the training set and 0.74 in the validation set, along with good sensitivity and positive predictive value.

This study presents a reliable preoperative nomogram to estimate the likelihood of LNM in submucosal EGC, providing valuable guidance for determining the most effective treatment strategies for patients.

Lymphatic involvement is sometimes detected during routine examination of intramucosal (pT1a) gastric cancer resected endoscopically. However, its clinical significance and association with the risk of metastasis remain unknown.

This was a retrospective cohort study of 6797 consecutive patients with pT1a gastric cancers treated by endoscopic submucosal dissection (ESD) at three institutions in Japan from January 2005 to August 2023. Patients with 49 uncommon-type gastric cancer types were excluded. The risk of metastasis for pT1a cancers with lymphatic involvement was quantified by comparing lymph node metastasis and/or metastatic recurrence in patient groups who underwent additional surgery post-ESD or did not undergo surgery but were followed up for > 3 years.

Among the 6748 pT1a cancers treated by ESD, 41 lesions (0.6%) had histologically confirmed lymphatic involvement. Among the 41 patients, 1 was excluded from the analysis of metastasis risk because the follow-up period after ESD without additional surgery was ≤ 3 years. Metastasis was identified in 1 of 40 patients analyzed (2.5%; 95% confidence interval [CI] 0.4%-12.9%), and was not detected in any of the 25 patients with pure differentiated-type lesions (0.0%; 95% CI 0.0%-13.7%).

The low prevalence of metastasis after ESD for pT1a gastric cancer with lymphatic involvement, particularly in patients with pure differentiated-type lesions, suggests a low risk of metastatic recurrence.

Lymph node metastasis plays a crucial role in determining the appropriate treatment approach for patients with gastric cancer (GC), particularly those in the T1-T2 stage. Currently available diagnostic strategies for GC with lymph nodes have limited accuracy. The present research aimed to create and validate diagnostic and prognostic nomograms specifically tailored for the T1-T2 stage GC patients with LNM.

We derived clinicopathological characteristics of patients diagnosed with GC from the Surveillance, Epidemiology, and End Results (SEER) database. We utilized univariate and multivariate logistic analyses to examine the risk factors linked with the occurrence of lymph node metastasis (LNM) in GC patients within the T1-T2 stage. Furthermore, the prognostic factors related to the T1-T2 stage GC patients with LNM were explored by univariate and multivariate cox analyses. Two nomograms were built by the risk factors screened above.

Ultimately, our study included 5,350 patients with T1-T2 stage GC. After identifying age, T stage, tumor size, primary site, grade, and histological type as risk factors for the LNM occurrence, we successfully developed a diagnostic nomogram utilizing these variables. Age, T stage, M stage, tumor size, primary site, grade, radiation, surgery, and chemotherapy were all independent prognostic factors that related to the T1 - T2 GC patients with LNM. The results of the AUC, calibration curve and decision curve analysis (DCA) showed excellent calibration performance and clinical applicability of the two nomograms. The Kaplan-Meier (K-M) curves clearly demonstrated a notable distinction in overall survival between low-risk and high-risk groups, highlighting the prognostic significance of the nomogram.

The establishment and validation of the two nomograms for T1-T2 GC patients with LNM were successful, serving as valuable tools for clinical decision-making and the formulation of personalized treatment approaches.

To treat early gastric cancer, one must choose between endoscopic treatment and surgical treatment. Endoscopic treatment has been developing significantly since the late 1990s and has made great progress up to the present. However, many patients with early gastric cancer still undergo unnecessary surgery or endoscopic procedures. This is due to the existence of a "gray zone" of ambiguities between endoscopic and surgical treatment. These ambiguities arise because the important factors in determining the treatment for early gastric cancer can only be fully understood after endoscopic or surgical resection or because of discrepancies between the factors identifiable before treatment and those identifiable after treatment. This article aims to explore these ambiguous factors and discuss methods and efforts to reduce them.

Lymph node metastasis, particularly to extraperigastric lymph nodes, is an important issue in determining the suitability of minimally invasive treatment for early gastric cancer. However, there is a paucity of research focused on identifying risk factors for extraperigastric lymph node metastasis, which is crucial for optimizing treatment selection.

Patients who underwent radical gastrectomy for early gastric cancer between 2007 and 2023 at Korea University Guro Hospital and Kyung Hee University Hospital at Gandong in Seoul, Korea, were reviewed retrospectively. We compared clinicopathologic characteristics to find out risk factors for lymph node metastasis between the no lymph node metastasis, perigastric lymph node metastasis, and extraperigastric lymph node metastasis groups.

A total of 1,021 patients were included in the study, with 90.0% in the lymph node metastasis, 7.94% in perigastric lymph node metastasis, and 2.06% in extraperigastric lymph node metastasis groups. Clinicopathologic analysis revealed the lymph node metastasis group exhibited a greater prevalence of mucosal lesions (55.2%), whereas the perigastric lymph node metastasis and extraperigastric lymph node metastasis groups demonstrated a greater incidence of SM3 invasion (55.6% and 52.4%, respectively; P < .001). Lymphatic invasion were found to be significantly different among the groups (P < .001). Multinomial logistic regression identified lymphatic invasion as a sole significant risk factor for the perigastric lymph node metastasis and extraperigastric lymph node metastasis groups. The 5-year relapse-free survival rates were 99.0% (lymph node metastasis), 94.5% (perigastric lymph node metastasis), and 100% (extraperigastric lymph node metastasis) (P = .011).

This multicenter retrospective analysis indicates that lymphatic invasion is the primary independent predictor of extraperigastric lymph node metastasis in patients with early gastric cancer. Future prospective research is warranted to validate this result and establish guidelines for treatment decision-making for early gastric cancer.

Endoscopic resection has been applied as an absolute indication for early gastric cancer showing intramucosal cancer ≤ 2 cm in diameter, differentiated-type adenocarcinoma without ulcerative findings. We describe the case of a 76-year-old man who underwent radical gastrectomy for alpha-fetoprotein-producing gastric cancer, in which the depth of invasion was clinically diagnosed as T1a after lymph node metastases were detected. Upper gastrointestinal endoscopy revealed a type 0-IIc tumor nearly 10 mm in diameter at the antrum. Computed tomography showed a 47-mm nodule along the common hepatic artery and a 22-mm nodule in the infrapyloric area. Both were pathologically confirmed as adenocarcinoma by endoscopic ultrasound-guided aspiration. No evidence of malignancy elsewhere was seen on 18F-fluorodeoxyglucose positron emission tomography. Serum alpha-fetoprotein level was elevated. Postoperatively, microscopic examination revealed moderately differentiated adenocarcinoma confined to the mucosal layer without lymphovascular involvement. Immunohistochemical examination for alpha-fetoprotein revealed that the metastatic nodes were positive despite the primary tumor being negative. The patient died of exacerbation of myelodysplastic syndrome 5 years 8 months postoperatively with no recurrence. Our experience suggests the need for further studies to validate whether the indications for endoscopic resection can apply to alpha-fetoprotein-producing gastric cancer in the same manner as to conventional gastric cancer.

Early-stage, poorly differentiated, non-ampullary duodenal adenocarcinomas are rare, and their clinicopathological features remain unelucidated. Between September 2006 and April 2022, 205 consecutive patients underwent endoscopic or surgical resection for early-stage non-ampullary duodenal adenocarcinomas at our hospital. There were no cases of poorly differentiated adenocarcinoma among the 188 cases of mucosal carcinoma. Meanwhile, among the 17 cases of submucosal invasive carcinoma, four cases were poorly differentiated adenocarcinomas. Herein, we report four cases of these carcinomas. All four lesions were reddish in color and were located on the oral side of the papilla. The gross types were either protruded (0-I) or mixed, elevated, and depressed (0-IIa + IIc). During preoperative diagnosis, submucosal invasion was suspected in all lesions, and biopsies were performed. Based on histological analyses of biopsy specimens, a diagnosis of poorly differentiated or signet-ring cell components was made in all cases, and a pancreaticoduodenectomy was performed. The median tumor size was 6.5 (range, 5-12) mm, and all lesions were poorly differentiated adenocarcinomas with submucosal invasion and lymph node metastasis. Regarding the tumor immunophenotype, one and three cases exhibited gastric and mixed gastrointestinal phenotypes, respectively. Two patients experienced metastatic recurrence; one of them died from the primary disease.

Gastric cancer is one of the most common cancers in both Korea and worldwide. Since 2004, the Korean Practice Guidelines for Gastric Cancer have been regularly updated, with the 4th edition published in 2022. The 4th edition was the result of a collaborative work by an interdisciplinary team, including experts in gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology, and guideline development methodology. The current guideline is the 5th version, an updated version of the 4th edition. In this guideline, 6 key questions (KQs) were updated or proposed after a collaborative review by the working group, and 7 statements were developed, or revised, or discussed based on a systematic review using the MEDLINE, Embase, Cochrane Library, and KoreaMed database. Over the past 2 years, there have been significant changes in systemic treatment, leading to major updates and revisions focused on this area. Additionally, minor modifications have been made in other sections, incorporating recent research findings. The level of evidence and grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation system. Key factors for recommendation included the level of evidence, benefit, harm, and clinical applicability. The working group reviewed and discussed the recommendations to reach a consensus. The structure of this guideline remains similar to the 2022 version. Earlier sections cover general considerations, such as screening, diagnosis, and staging of endoscopy, pathology, radiology, and nuclear medicine. In the latter sections, statements are provided for each KQ based on clinical evidence, with flowcharts supporting these statements through meta-analysis and references. This multidisciplinary, evidence-based gastric cancer guideline aims to support clinicians in providing optimal care for gastric cancer patients.

Differences in demographics, medical expertise, and patient healthcare resources across countries have led to significant variations in guidelines. In light of these differences, in this review, we aimed to explore and compare the most recent updates to gastric cancer treatment from five guidelines that are available in English. These English-version guidelines, which have been recently published and updated for journal publication, include those published in South Korea in 2024, Japan in 2021, China in 2023, the United States in 2024, and Europe in 2024. The South Korean and Japanese guidelines provide a higher proportion of content to endoscopic and surgical treatments, reflecting their focus on minimally invasive techniques, function-preserving surgeries, and systemic therapy. The Chinese guidelines provide recommendations addressing not only surgical approaches but also perioperative chemotherapy and palliative systemic therapy. Meanwhile, in the United States and European guidelines, a higher proportion of the content is dedicated to perioperative and palliative systemic therapy, aligning with their approaches to advanced-stage disease management. All guidelines address surgical and systemic chemotherapy treatments; however, the proportion and emphasis of content vary based on the patient distribution and treatment approaches specific to each country. With emerging research findings on gastric cancer treatment worldwide, the national guidelines are being progressively revised and updated. Understanding the commonalities and differences among national guidelines, along with the underlying evidence, can provide valuable insights into the treatment of gastric cancer.

This article provides an overview of recent advances in endoscopic resection techniques. It includes the brief overview of endoscopic submucosal dissection, regional differences in ESD indications, innovation of ESD techniques, and expansion to full-thickness resection. The article covers cold snare polypectomy for small polyps with tips, underwater endoscopic mucosal resection (U-EMR) for sessile lesions with tips and expanding role of U-EMR, and the key assistive techniques for ESD that have improved the safety and efficacy. Furthermore, it discusses the emerging field of endoscopic full-thickness resection including device-assisted and freehand exposure techniques.

Background: Endoscopic Submucosal Dissection (ESD) has become the standard therapy for early malignant lesions in the gastrointestinal tract and has shown as good oncological surgery results. Approximately 30% of ESDs do not meet the criteria for oncological curability, and upfront surgery is indicated. Hence, about 40% of patients with an indication for surgery are advised against surgery because of comorbidities and an advanced age. Methods: We performed a multicenter retrospective cohort study on the long-term outcomes of non-curative ESDs, performed between 2009 and May 2024, without additional tumor therapy. The primary outcome was the recurrence of malignancy, either local malignancy or lymph node metastasis during follow-up, or death. We compared the outcomes between two cohorts: after non-curative ESD (ncESD) and after curative ESD (cESD). Results: A total of 374 ESDs were analyzed in this study. Overall, the technical success rate was 91%, and the oncological curative resection criteria were met in 70.9% of patients. Severe complications occurred in 5% of cases without procedure-associated mortality. In the ncESD group, 20% (7/35) of patients had a recurrence of malignancy primarily due to positive horizontal margins in the resection specimens, and 3 out of 35 died due to a non-oncological reason during the follow-up (mean length 36.6 months). In the cESD group, 3% (1/33) of patients had tumor recurrence, and 1 patient died because of a non-oncological reason. The tumor recurrence rate between the cohorts was significant (p = 0.017), and overall mortality did not show significance (p = 0.33). Conclusions: Especially in the elderly and multimorbid patients, the recommendation to perform rescue surgery after non-curative ESD remains challenging. Residual malignancy rates in surgical resection specimens are low, recurrence rates of malignancy are low, and mortality rates for non-oncological reasons are high in this population. There is a need for more data for the individualization of patient management after non-curative ESD.

Lymph node metastasis significantly affects the prognosis of early gastric cancer patients. EUS plays a crucial role in the preoperative assessment of early gastric cancer. This study evaluated the efficacy of EUS in identifying lymph node metastasis in early gastric cancer patients and developed a risk score model to aid in choosing the best treatment options.

We retrospectively analyzed the effectiveness of EUS for detecting lymph node metastasis in early gastric cancer patients. A risk score model for predicting lymph node metastasis preoperatively was created using independent risk factors identified through binary logistic regression analysis and subsequently validated. Receiver operating characteristic curves were generated for both the development and validation cohorts.

The overall accuracy of EUS in identifying lymph node metastasis was 85.3%, although its sensitivity (29.2%) and positive predictive value (38.7%) were relatively low. Patients were categorized based on preoperative risk factors for lymph node metastasis, including tumor size of ≥20 mm, lymph nodes of ≥10 mm, body mass index of ≥24 kg/m2, and lymph node metastasis on CT scans. A 7-point risk score model was developed to assess the likelihood of lymph node metastasis. The areas under the receiver operating characteristic curve for the development and validation sets were 0.842 and 0.837, respectively, with sensitivities of 64% and 79%, respectively.

We developed a practical risk score model based on preoperative factors to help EUS predict lymph node metastasis in early gastric cancer patients, guiding the selection of optimal treatment approaches for these patients.

To analyze the diagnostic efficiency of the four absolute endoscopic submucosal dissection (ESD) indications for lymph node metastasis (LNM) of Chinese patients with early gastric cancer (EGC).

We retrospectively analyzed EGC patients who underwent radical D2 gastrectomy from January 2019 to December 2022. We evaluated the rate of LNM, false-negative rate, and negative predictive value of the four ESD indications.

Of enrolled 2722 EGC patients, 388 (14.3%) patients presented LNM. Tumor size > 2 cm, ulceration, submucosal invasion, undifferentiated type, and lymphovascular invasion were independent risk factors of LNM in patients with EGC. 1062 (39%) cases of EGC conformed to the four EDS indications; however, 4% of them had LNM. 451 cases were fully in accord with the fourth ESD indication (undifferentiated intramucosal carcinoma without ulceration and a maximum lesion diameter of ≤ 2 cm), and 35 of them had LNM, with a false-negative rate (FNR) of 9.02% and a negative predictive value (NPV) of 92.24%. There was significant difference among the four indications in terms of the rate of LNM (1.0% vs 1.5% vs 1.3% vs 7.8%, P < 0.001), FNR (1.03% vs 0.52% vs 0.26% vs 9.02%, P < 0.001), and NPV (98.99% vs 98.53% vs 98.75% vs 92.24%, P < 0.001).

Overall, the fourth ESD indication was associated with a high rate of LNM compared to the other three indications. Thus, it might not be safe to classify it as an absolute indication in Chinese patients with EGC.

Bleeding after endoscopic submucosal dissection (ESD) for gastric tumors in patients taking antithrombotic drugs, in particular direct oral anticoagulants (DOACs), remains unresolved; therefore, we evaluated the risk factors for post-ESD bleeding and drug differences in patients taking DOACs.

We included 278 patients taking antithrombotic drugs who underwent gastric ESD between January 2017 and March 2022. Antithrombotic drugs were withdrawn following the 2017 guidelines (Appendix on anticoagulants including DOACs). To further clarify differences in antithrombotic agents' effects, the peri-cancerous mucosa in the resected specimen was pathologically evaluated according to the Updated Sydney System. Multivariate analysis was performed to assess the risk of post-ESD bleeding.

The incidence of post-ESD bleeding in patients taking DOACs was 19.6% (10/51). Among patients taking antithrombotic drugs, DOACs were identified as a possible factor involved in post-ESD bleeding (odds ratio [OR] 4.92). Among patients taking DOACs, possible factors included resection length diameter ≥30 mm (OR 3.72), presence of neutrophil infiltration (OR 2.71), lesions occurring in the lower third of stomach (OR 2.34), and preoperative antiplatelet use (OR 2.22). Post-ESD bleeding by DOAC type was 25.0% of patients (4/16) receiving apixaban, in 20.0% (3/15) receiving edoxaban, in 21.4% (3/14) receiving rivaroxaban, and in none of those receiving dabigatran.

The administration of DOACs was shown to be a possible factor involved in post-ESD bleeding, and risk factors for patients taking DOACs included neutrophil infiltration. The pharmacological differences in the effects of DOACs contributing to bleeding in gastric ulcers suggest comparatively less bleeding with dabigatran after ESD.

Background and aims: Endoscopic submucosal dissection (ESD) has become a standard treatment for early gastric cancer (EGC), often fulfilling guideline criteria (GC) or expanded criteria (EC). When lesions exceed the EC, surgical resection is recommended. However, a subgroup of these patients are not treated surgically. The aim of this study was to investigate the long-term follow-up of patients after ESD for EGC outside the EC (out of indication; OI). Methods: Patients who were included in the prospective German ESD registry were analyzed when ESD was performed for EGC. Patients were stratified in three groups according to histopathological features (GC, EC and OI). The results were evaluated in terms of patient characteristics, procedure characteristics and follow-up data. Results: Over a 48-month period, 195 patients from 14 German centers were included. In total, 71 lesions (36.4%) met the guideline criteria, 70 lesions (35.9%) corresponded to the expanded criteria and 54 lesions (27.7%) turned out to be OI. The R0 resection rate was significantly higher for the GC and EC groups than for the OI group (94.4% vs. 84.3% vs. 55.6%, p < 0.001). Additional surgery was not performed in 72% (39/54) of patients in the OI group. During a mean follow-up of 37 months, overall survival showed no significant difference between the EC and OI groups when endoscopic follow-up was performed without additional surgery (p = 0.064). Conclusions: The results show that a good long-term survival can be achieved after ESD for patients with OI lesions without additional surgery. The treatment decision has to be made on an individual basis, taking the patient's comorbidities and the risk of surgical resection into account.

Gastric cancer (GC) is the fifth most frequently diagnosed cancer and the fifth most common cause of cancer death in the world. Regarding the age at which the diagnosis was made, GC is divided into early-onset gastric cancer (EOGC-up to 45 years of age) and conventional GC (older than 45). EOGC constitutes approximately 10% of all GCs. Numerous reports indicate that EOGC is more aggressive than conventional GC and is often discovered at an advanced tumor stage, which has an impact on the five-year survival rate. The median survival rate for advanced-stage GC is very poor, amounting to less than 12 months. Risk factors for GC include family history, alcohol consumption, smoking, Helicobacter pylori, and Epstein-Barr virus infection. It has been shown that a proper diet and lifestyle can play a preventive role in GC. However, research indicates that risk factors for conventional GC are less correlated with EOGC. In addition, the unclear etiology of EOGC and the late diagnosis of this disease limit the possibilities of effective treatment. Genetic factors are considered a likely cause of EOGC, as young patients are less exposed to environmental carcinogens. Research characterizing GC in young patients is scarce. This comprehensive study presents all aspects: epidemiology, risk factors, new treatment strategies, and future directions.

In this editorial, we explore the challenges of managing noncurative resections in early gastric cancer after endoscopic submucosal dissection (ESD), starting from the consideration recently made by Zhu et al. Specifically, we evaluate the management of eCura C1 lesions, where decisions regarding further interventions are pivotal yet contentious. Collaboration among endoscopists, surgeons, and pathologists is underscored to refine risk assessment and personalize therapeutic management. Recent advancements in ESD techniques and interdisciplinary collaboration offer opportunities for outcome optimization in managing eCura C1 lesions. Moreover, despite needing further clinical validation, molecular biomarkers have emerged as promising tools for enhancing prognostication. This manuscript highlights the ongoing research attempts to define treatment paradigms effectively and evaluates the potential of emerging options, ultimately aiming to improve patient care and outcomes in this complex clinical scenario.

In early gastric cancer (EGC), the presence of lymph node metastasis (LNM) is a crucial factor for determining the treatment options. Endoscopic resection is used for treatment of EGC with minimal risk of LNM. However, owing to the lack of definitive criteria for identifying patients who require additional surgery, some patients undergo unnecessary additional surgery. Considering that histopathologic patterns are significant factor for predicting lymph node metastasis in gastric cancer, we aimed to develop a machine learning algorithm which can predict LNM status using hematoxylin and eosin (H&E)-stained images. The images were obtained from several institutions. Our pipeline comprised two sequential approaches including a feature extractor and a risk classifier. For the feature extractor, a segmentation network (DeepLabV3+) was trained on 243 WSIs across three datasets to differentiate each histological subtype. The risk classifier was trained with XGBoost using 70 morphological features inferred from the trained feature extractor. The trained segmentation network, the feature extractor, achieved high performance, with pixel accuracies of 0.9348 and 0.8939 for the internal and external datasets in patch level, respectively. The risk classifier achieved an overall AUC of 0.75 in predicting LNM status. Remarkably, one of the datasets also showed a promising result with an AUC of 0.92. This is the first multi-institution study to develop machine learning algorithm for predicting LNM status in patients with EGC using H&E-stained histopathology images. Our findings have the potential to improve the selection of patients who require surgery among those with EGC showing high-risk histological features.

Gastric cancer with fusion genes involving the Rho GTPase-activating protein domain (RhoGAP-GC) is mainly included in the genomically stable type of The Cancer Genome Atlas classification. Clinical implications and histological characteristics of RhoGAP-GC in the early phase remain unclear.

We analyzed 878 consecutive pT1b GCs for RhoGAP and its partner genes using fluorescence in situ hybridization assay.

RhoGAP fusion was detected in 57 (6.5%) GCs. Univariate analysis revealed that female sex, middle-lower third tumor location, advanced macroscopic type, tumor diameter > 2 cm, pT1b2, lymphatic invasion, venous invasion, negative EBER-ISH, and RhoGAP fusion were significantly associated with lymph node metastasis (LNM). Multivariate analysis presented RhoGAP fusion, lymphatic invasion, tumor diameter > 2 cm, advanced macroscopic type, venous invasion, and middle-lower third tumor location as independent risk factors for LNM. Notably, RhoGAP fusion had the highest odds ratio (3.92) for LNM among analyzed parameters (95% CI 2.12-7.27; p < 0.001). Compared to non-RhoGAP-GCs, RhoGAP-GCs were significantly frequent in younger females and showed the highest incidence of lymphatic invasion (56.2%) and LNM (49.1%) (p < 0.001). Histologically, microtubular architecture with pseudo-trabecular interconnection and small aggregations of tumor cells with a varied amount of cytoplasmic mucin, named "microtubular-mucocellular (MTMC) histology," was found in 93.0% (53 of 57) of RhoGAP-GCs in the intramucosal area. MTMC histology showed high sensitivity and negative predictive value (93.0% and 99.4%, respectively) for RhoGAP fusion, albeit positive predictive value is low (34.9%).

RhoGAP-GC is linked to a characteristic MTMC histology and a high incidence of LNM.

Cancer cell invasion is a critical cause of fatality in cancer patients. Physiologically relevant tumor models play a key role in revealing the mechanisms underlying the invasive behavior of cancer cells. However, most existing models only consider interactions between cells and extracellular matrix (ECM) components while neglecting the role of matrix stiffness in tumor invasion. Here, we propose an effective approach that can construct stiffness-tunable substrates using digital mirror device (DMD)-based optical projection lithography to explore the invasion behavior of cancer cells. The printability, mechanical properties, and cell viability of three-dimensional (3D) models can be tuned by the concentration of prepolymer and the exposure time. The invasion trajectories of gastric cancer cells in tumor models of different stiffness were automatically detected and tracked in real-time using a deep learning algorithm. The results show that tumor models of different mechanical stiffness can yield distinct regulatory effects. Moreover, owing to the biophysical characteristics of the 3D in vitro model, different cellular substructures of cancer cells were induced. The proposed tunable substrate construction method can be used to build various microstructures to achieve simulation of cancer invasion and antitumor screening, which has great potential in promoting personalized therapy.

When treating undifferentiated-type early gastric cancer (UD-EGC) that is limited to the mucosa (clinically T1a), endoscopic submucosal dissection (ESD) can be considered if the tumor is 2 cm or less and is not ulcerated. However, there is insufficient evidence to determine the relationships between tumor size and oncological safety of ESD in UD-EGC.

The pathology reports of Korean patients who were diagnosed with UD-EGC (n = 5286) were retrospectively reviewed. The cumulative incidence of lymph node metastasis (LNM) according to tumor size was evaluated in subgroups. The tumor-size cut-off was identified as the upper limit of the 95% confidence interval (CI) of cumulative LNM incidence that did not exceed 1.0%.

We identified 1516 patients with non-ulcerated T1a tumors ≤2 cm in size. Among patients without lymphatic invasion, 1.5% (95% CI 0.91-2.16%) had LNM. In patients with poorly differentiated tubular adenocarcinoma (PD), LNM increased from 0 to 0.74% based on a tumor size of 1.0 cm. Regardless of tumor size, smaller percentages of undifferentiated-type (UD) and poorly cohesive carcinoma (PCC) patients experienced LNM than did those with PD. In non-ulcerated mucosal cancer without lymphatic invasion and tumor size ≤0.9 cm, no LNM was observed in patients with UD (95% CI 0-0.53%), PCC (95% CI 0-0.59%), or PD (95% CI 0-0.86%) histologic type.

In patients diagnosed with non-ulcerated T1a UD-EGC, ESD can be performed if the tumor size is 0.9 cm or less, regardless of histologic type.

A small portion of patients are diagnosed with early gastric cancer (EGC) and undergo endoscopic submucosal dissection (ESD) at a young age. However, their clinical outcomes are rarely known.

We investigated to identify the feasibility and clinical outcomes of ESD for EGC focusing on young patients.

We analyzed the clinical characteristics and outscomes of patients who had undergone ESD for the treatment of EGC at < 50 years of age. We enrolled patients who had been diagnosed with EGC and had undergone ESD between 2006 and 2020. We divided them by age as follows: ≤ 50 and > 50 years into the young age (YA) and other age (OA) groups, respectively.

Altogether, 1681 patients underwent ESD for EGC (YA group: 124 [7.4%], OA group: 1557 [92.6%]). The YA group had less severe atrophy and more undifferentiated (37.1% vs. 13.9%, P < 0.001) and diffuse type (25% vs. 7.7%, P < 0.001) histology. The curative resection rate was not significantly different between the groups. However, among 1075 patients who had achieved curative resection and had been followed-up for > 12 months, the YA group had a lower incidence of MGN (5.2% vs. 17.5%, P = 0.004) and MGC (2.6% vs. 10.9%, P = 0.019) than those exhibited by the OA group. The YA group was a significant negative predictor of MGN (odds ratio [OR]: 2.983, 95% confidence interval [CI] 1.060-8.393, P = 0.038), and marginally negative predictor in MGC (OR: 3.909, 95% CI: 0.939-16.281, P = 0.061).

ESD is a favorable and effective therapeutic modality for EGC patients aged < 50 years, once curative resection is achieved.

Endoscopic submucosal dissection (ESD) for over 2 cm in size undifferentiated type (UD type) early gastric cancer (EGC) confined to the mucosa is not only challenging, but also long-term outcomes are not well known.

To evaluate the long-term outcomes of ESD done for UD type EGCs confined to the mucosa over 2 cm in size and compare the results with those where the lesions were less than 2 cm.

143 patients with UD type EGC confirmed on histology after ESD at a tertiary hospital were reviewed. Cases with synchronous and metachronous lesions and a case with emergency surgery after ESD were excluded. A total of 137 cases were enrolled. 79 cases who underwent R0 resection were divided into 2 cm or less (group A) and over 2 cm (group B) in size.

Among 79 patients who underwent R0 resection, the number in group A and B were 51 and 28, respectively. The mean follow-up period (SD) was 79.71 ± 45.42 months. There was a local recurrence in group A (1/51, 2%) and group B (1/28, 3.6%) respectively. This patient in group A underwent surgery while the patient in group B underwent repeated ESD with no further recurrences in both patients. There was no regional lymph node metastasis, distant metastasis, and deaths in both groups. With R0 resection strategy for ESD on lesions over 2 cm, 20.4% (28/137) of patients were able to avoid surgery compared with expanded indication.

If R0 resection is achieved by ESD, UD type EGCs over 2 cm also showed good and similar clinical outcomes as compared to lesions less than 2 cm when followed for over 5 years. With R0 resection strategy, several patients can avoid surgery.

Whether the Western pT1acN0M0 gastric cancer (GC) patients who met the Japanese expanded criteria could be the candidates for endoscopic treatment (ET) remains unclear because of unknown long-term survival outcomes.

A retrospective cohort study using data from the Surveillance, Epidemiology, and End Results (SEER) program was performed. The survival differences between pT1acN0M0 gastric adenocarcinoma patients who received ET or gastrectomy treatment (GT) were evaluated using multivariate survival analysis.

A total of 314 pT1acN0M0 gastric adenocarcinoma patients who met the expanded criteria were included, 46 patients received ET and 268 patients received GT. pT1acN0M0 gastric adenocarcinoma patients met the expanded criteria underwent ET experienced a similar hazard of cancer-specific death compared with those underwent GT both in the multivariate Cox survival analysis (adjusted hazard ratio [HR]; 1.18, 95% confidence interval [CI] 0.40-3.49; P = 0.766) and the multivariate competing risk model (subdistribution HR [SHR], 1.12, 95% CI 0.38-3.29; P = 0.845). The result that pT1acN0M0 gastric adenocarcinoma patients met the expanded criteria underwent ET experienced comparable survival outcomes to those who underwent GT did not change even compared with those who underwent GT with > 15 lymph nodes examined (adjusted HR, 1.55, 95% CI 0.44-5.49; P = 0.499; SHR, 1.47, 95% CI 0.44-4.88; P = 0.532).

The ET can be considered in Western pT1acN0M0 gastric adenocarcinoma patients who met the Japanese expanded criteria. However, a prospective study should be warranted.

Malignancies in the upper gastrointestinal tract are amenable to endoscopic resection at an early stage. Achieving a curative resection is the most stringent quality criterion, but post-resection risk assessment and aftercare are also part of a comprehensive quality program.

Various factors influence the achievement of curative resection. These include endoscopic assessment prior to resection using chromoendoscopy and HD technology. If resectability is possible, it is particularly important to delineate the lateral resection margins as precisely as possible before resection. Furthermore, the correct choice of resection technique depending on the lesion must be taken into account. Endoscopic submucosal dissection is the standard for esophageal squamous cell carcinoma and gastric carcinoma. In Western countries, it is becoming increasingly popular to treat Barrett's neoplasia over 2 cm in size and/or with suspected submucosal infiltration with en bloc resection instead of piece meal resection. After resection, risk assessment based on the histopathological resection determines the patient's individual risk of lymph node metastases, particularly in the case of high-risk lesions. This is categorized according to the current literature.

This review presents clinical algorithms for endoscopic resection of esophageal SCC, Barrett's neoplasia, and gastric neoplasia. The algorithms include the pre-resection assessment of the lesion and the resection margins, the adequate resection technique for the respective lesion, as well as the post-resection risk assessment with an evidence-based recommendation for follow-up therapy and surveillance.

Papillary adenocarcinoma is classified to differentiated-type gastric cancer and is indicated for endoscopic submucosal dissection. However, due to its rare nature, there are limited studies on it. The purpose of this study was to determine the outcome of endoscopic submucosal dissection in patients with papillary-type early gastric cancer and to find the risk factors of lymph node metastasis.

Patients diagnosed with papillary-type early gastric cancer at eight medical centers, who underwent endoscopic submucosal dissection or surgical treatment, were retrospectively reviewed. The clinical results and long-term outcomes of post-endoscopic submucosal dissection were evaluated, and the risk factors of lymph node metastasis in the surgery group were analyzed.

One-hundred and seventy-six patients with papillary-type early gastric cancer were enrolled: 44.9% (n=79) in the surgery group and 55.1% (n=97) in the endoscopic submucosal dissection group. As a result of endoscopic submucosal dissection, the en bloc resection and curative resection rates were 91.8% and 86.6%, respectively. The procedure-related complication rate was 4.1%, and local recurrence occurred in 3.1% of patients. Submucosal invasion (odds ratio, 3.735; 95% confidence interval, 1.026 to 12.177; p=0.047) and lymphovascular invasion (odds ratio, 7.636; 95% confidence interval, 1.730 to 22.857; p=0.004) were the risk factors of lymph node metastasis in papillary-type early gastric cancer patients.

The clinical results of endoscopic submucosal dissection in papillary-type early gastric cancer were relatively favorable, and endoscopic submucosal dissection is considered safe if appropriate indications are confirmed by considering the risk of lymph node metastasis.

Gastric cancer is one of the most common malignant tumors in the digestive system in China. Few comprehensive practice guidelines for early gastric cancer in China are currently available. Therefore, we created the Chinese national clinical practice guideline for the prevention, diagnosis, and treatment of early gastric cancer.

This clinical practice guideline (CPG) was developed in accordance with the World Health Organization's recommended process and with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) in assessing evidence quality. We used the Evidence to Decision framework to formulate clinical recommendations to minimize bias and increase transparency in the CPG development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and the Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guidelines to ensure completeness and transparency of the CPG.

This CPG contains 40 recommendations regarding the prevention, screening, diagnosis, treatment, and follow-up of early gastric cancer based on available clinical studies and guidelines. We provide recommendations for the timing of Helicobacter pylori eradication, screening populations for early gastric cancer, indications for endoscopic resection and surgical gastrectomy, follow-up interval after treatment, and other recommendations.

This CPG can lead to optimum care for patients and populations by providing up-to-date medical information. We intend this CPG for widespread adoption to increase the standard of prevention, screening, diagnosis, treatment, and follow-up of early gastric cancer; thereby, contributing to improving national health care and patient quality of life.

Endoscopic submucosa dissection (ESD) allows complete excision of the whole lesion, which results in a higher percentage of complete excision and an improved quality of life by minimizing the amount of excision as opposed to an endoscopic mucosal resection (EMR). Although ESD is now being carried out in the majority of hospitals, ESD's possible complications (such as trauma and perforation) have given rise to doubts about ESD practices in patients with early-stage stomach cancer when deciding on therapy and reimbursement. This study was designed to evaluate the effectiveness and safety of ESD over EMR in treating early-stage stomach cancer. Four main databases have been searched, including EMBASE and published. The ROBINS-I tool suggested in the Cochrane Handbook has been applied to evaluate the quality of the chosen trials. It may better reflect the risk of bias in the included studies. The meta-analyses were carried out with ReMan 5.3, and the results were treated with endote. Seven cohort studies have been completed. Meta analysis indicated that EMR and ESD surgery did not differ significantly from each other in terms of postoperative haemorrhage (OR, 0.76; 95%CI, 0.56,1.04 p = 0.09); EMR, however, was associated with a lower rate of postoperative perforation than ESD surgery (OR, 0.36; 95%CI, 0.24,0.54 p < 0.0001). Taking into account that ESD and EMR did not differ significantly in the risk of wound bleeding, even though the risk of perforation is not likely to result in life-threatening illness. In the analysis of these data, however, the potential advantages of EMR might be greater than ESD.

The microsurface structure reflects the degree of damage to the glands, which is related to the invasion depth of early gastric cancer. To evaluate the diagnostic value of quantitative microsurface structure analysis for estimating the invasion depth of early gastric cancer.

White-light imaging and narrow-band imaging (NBI) endoscopy were used to visualize the lesions of the included patients. The area ratio and depth-predicting score (DPS) of each patient were calculated; meanwhile, each lesion was examined by endoscopic ultrasonography (EUS).

Ninety-three patients were included between 2016 and 2019. Microsurface structure is related to the histological differentiation and progression of early gastric cancer. The receiver operating characteristic curve showed that when an area ratio of 80.3% was used as a cut-off value for distinguishing mucosal (M) and submucosal (SM) type 0-II gastric cancers, the sensitivity, specificity, and accuracy were 82.9%, 80.2%, and 91.6%, respectively. The accuracies for distinguishing M/SM differentiated and undifferentiated early gastric cancers were 87.4% and 84.8%, respectively. The accuracy of EUS for distinguishing M/SM early gastric cancer was 74.9%. DPS can only distinguish M-SM1 (SM infiltration <500 μm)/SM (SM infiltration ≥500 μm) with an accuracy of 83.8%. The accuracy of using area ratio for distinguishing 0-II early gastric cancers was better than those of using DPS and EUS (P < 0.05).

Quantitative analysis of microsurface structure can be performed to assess M/SM type 0-II gastric cancer and is expected to be effective for judging the invasion depth of gastric cancer.

A 70-year-old man was diagnosed with early gastric cancer with ulcerative findings. Endoscopic submucosal dissection as an absolute indication was performed, and en bloc resection was achieved. Pathological examination revealed a well-differentiated adenocarcinoma, 3 × 2 mm in size, intramucosal, with an ulcerative scar, no lymphovascular invasion, and a tumor-free margin. We diagnosed it as a curative resection and followed up with annual endoscopy. Sixteen months after endoscopic submucosal dissection, esophagogastroduodenoscopy revealed a singular ulcer scar; however, serum carcinoembryonic antigen level was elevated. Computed tomography scan showed wall thickening of the gastric antrum and an irregular mass on the dorsal side. Additionally, 18F-fluorodeoxyglucose positron emission tomography/coomputed tomography showed 18F-fluorodeoxyglucose uptake in the gastric antrum, irregular mass, and liver. Endoscopic ultrasonography revealed an internally heterogeneous mass in the gastric antrum region extending from the submucosal layer to the muscularis propria layer. Using an endoscopic ultrasonography-guided fine needle biopsy with a 22-gauge needle for the mass, we diagnosed local recurrence with the submucosal tumor-like appearance, lymph node metastasis, and liver metastases. Unfortunately, the patient died of gastric cancer 3 months after the diagnosis. Here, we report a rare case of local recurrence in the submucosal layer, lymph node metastasis, and liver metastases 16 months after curative endoscopic submucosal dissection.

Background: This study aimed to assess the completion rate and postoperative bleeding incidence of endoscopic submucosal dissection (ESD) for gastric tumors under continuous antithrombotic therapy. Methods: A prospective observational study was conducted including 88 patients with 100 gastric lesions who underwent gastric endoscopic submucosal dissection (ESD) and received continuous antithrombotic therapy. Additionally, retrospective data on gastric ESD in 479 patients with 534 lesions who did not receive antithrombotic therapy were collected for comparison. Results: The en bloc resection rates (100% in the continuous antithrombotic therapy group vs. 100% in the non-antithrombotic therapy group) and complete resection rates (97.0% vs. 96.3%, respectively) were high and comparable between the groups. No significant differences were found in the specimen size or procedure time. Perforation rates were low (0% vs. 2.3%, respectively) and were not significantly different between the groups. However, postoperative bleeding occurred significantly more frequently in the continuous antithrombotic therapy group (10.2% vs. 4.2%, respectively) than in the non-antithrombotic therapy group. The subgroup analysis revealed a higher incidence of postoperative bleeding in patients receiving thienopyridine derivatives. Conclusions: Continuous administration of antithrombotic agents, especially thienopyridines, increased the risk of postprocedural hemorrhage following gastric ESD. These findings support the need for careful consideration of pharamcological management before ESD, aligning with the current guidelines.