Early Immune Remodeling Steers Clinical Response to First-Line Chemoimmunotherapy in Advanced Gastric Cancer.

Adding anti-programmed cell death protein 1 (anti-PD-1) to 5-fluorouracil (5-FU)/platinum improves survival in some advanced gastroesophageal adenocarcinomas (GEA). To understand the effects of chemotherapy and immunotherapy, we conducted a phase II first-line trial (n = 47) sequentially adding pembrolizumab to 5-FU/platinum in advanced GEA. Using serial biopsy of the primary tumor at baseline, after one cycle of 5-FU/platinum, and after the addition of pembrolizumab, we transcriptionally profiled 358,067 single cells to identify evolving multicellular tumor microenvironment (TME) networks. Chemotherapy induced early on-treatment multicellular hubs with tumor-reactive T-cell and M1-like macrophage interactions in slow progressors. Faster progression featured increased MUC5A and MSLN containing treatment resistance programs in tumor cells and M2-like macrophages with immunosuppressive stromal interactions. After pembrolizumab, we observed increased CD8 T-cell infiltration and development of an immunity hub involving tumor-reactive CXCL13 T-cell program and epithelial interferon-stimulated gene programs. Strategies to drive increases in antitumor immune hub formation could expand the portion of patients benefiting from anti-PD-1 approaches. SIGNIFICANCE: The benefit of 5-FU/platinum with anti-PD-1 in first-line advanced gastric cancer is limited to patient subgroups. Using a trial with sequential anti-PD-1, we show coordinated induction of multicellular TME hubs informs the ability of anti-PD-1 to potentiate T cell-driven responses. Differential TME hub development highlights features that underlie clinical outcomes. This article is featured in Selected Articles from This Issue, p. 695.

Delayed Perforation Occurring after Gastric Endoscopic Submucosal Dissection: Clinical Features and Management Strategy.

Background/Aims: Delayed perforation is a rare but serious adverse event of gastric endoscopic submucosal dissection (ESD). The aim of this study was to clarify the clinical features and appropriate management strategy of patients with delayed perforation. Methods: Among 11,531 patients who underwent gastric ESD, the clinical features and outcomes of patients who experienced delayed perforation were retrospectively reviewed and compared with those of the control group. Results: Delayed perforation occurred in 15 of 11,531 patients (0.13%). The patients with delayed perforation were significantly older than those without delayed perforation (p=0.027). The median time to diagnosis of delayed perforation was 28.8 hours (range, 14 to 71 hours). All 15 patients with delayed perforation complained of severe abdominal pain after gastric ESD and underwent subsequent chest X-rays (CXRs) for evaluation. In subsequent CXR, free air was found in 12 patients (80%). For three (20%) patients without free air in CXR, delayed perforation was finally diagnosed by computed tomography. Leukocytosis was significantly less frequent in the patients without free air in CXR (p=0.022). A perforation hole smaller than 1 cm in size was more frequently observed in the six patients who underwent successful non-surgical treatments than in the nine patients who underwent surgery (p<0.001). There was no mortality related to delayed perforation. Conclusions: One-fifth of the patients with delayed perforation did not show free air in CXR and exhibited less leukocytosis than those with free air. Non-surgical treatments including endoscopic closure might be considered as an initial treatment modality for delayed perforation smaller than 1 cm.

Outcomes of Primary Esophagectomy and Esophagectomy after Endoscopic Submucosal Dissection for Superficial Esophageal Squamous Cell Carcinoma: A Propensity-Score-Matched Analysis.

Even though the conventional treatment for T1 esophageal cancer is surgery, ESD is becoming the primary treatment. Currently, it is unknown whether secondary esophagectomy after endoscopic submucosal dissection (ESD) is comparable to primary esophagectomy when considering outcomes in patients with T1 esophageal cancer. We compared short- and long-term clinical outcomes between the two groups. Primary surgery (esophagectomy) was performed in 191 patients between 2003 and 2014, and 62 patients underwent secondary surgery (esophagectomy) after ESD for T1 esophageal cancer between 2007 and 2019. Propensity matching was performed for age, sex, Charlson Comorbidity Index (CCI), location, pathology, degree of differentiation, tumor size, and invasion depth. Lymph node metastasis (LNM), overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), and post-operative complications were compared between groups. Sixty-eight patients were included after propensity score matching; LNM, OS, DSS, and RFS were comparable between the two groups. Comparing primary and secondary surgery, the respective LNM rates were 23.5% and 26.5%, 6-year OS 78.0% and 89.7%, p = 0.15; DSS were 80.4% and 96.8%, p = 0.057; and RFS were 80.8% and 89.7%, p = 0.069. Comparing the adverse events between the two groups, there was no significant difference in the overall adverse events. However, more early complications were observed in the primary surgery group than in the secondary surgery group (50% vs. 20.6%, p = 0.021). Secondary surgery did not increase the risk of LNM. The long-term outcomes were comparable. Therefore, attempts to perform upfront ESD for superficial esophageal squamous cell cancers are justified.

Antithrombotic Therapy Increases the Risk of Bleeding after Endoscopic Submucosal Dissection for Early Gastric Cancer: A Propensity Score-Matched Analysis.

Whether antithrombotic agent (ATA) usage increases the risk of gastric post-endoscopic submucosal dissection (ESD) bleeding remains controversial. The aim of this study was to elucidate the effects of usage, type, and cessation timing of ATA on post-ESD bleeding. A total of 4775 early gastric cancer patients undergoing ESD were analyzed; 1:3 propensity score matching between ATA and non-ATA groups resulted in 318 and 767 matched patients in each group, respectively. Outcomes were compared between the two groups using a generalized estimating equation method. After matching, post-ESD bleeding rates in ATA users and non-users were 9.1% and 4.2%, respectively (p = 0.001). In multivariable analysis, ATA usage was independently associated with an increased risk of post-ESD bleeding (adjusted odds ratio: 2.28, 95% confidence interval: 1.34-3.86). Both the continued or insufficient cessation groups and the sufficient cessation group had an increased incidence of post-ESD bleeding compared to their matched controls (12.5% versus 5.2%, p = 0.048; 8.1% versus 3.9%, p = 0.014). Post-ESD bleeding rates in antiplatelet agent users were significantly higher than those of their matched controls (8.3% versus 4.2%, p = 0.010). ATA usage increased the risk of post-ESD bleeding even after its sufficient cessation. Careful observation after ESD is required regardless of the cessation status of ATA.

Erratum: Korean Practice Guidelines for Gastric Cancer 2022: An Evidence-based, Multidisciplinary Approach.

This corrects the article on p. 3 in vol. 23, PMID: 36750993.

Effect of renal insufficiency on the short- and long-term outcomes of endoscopic submucosal dissection for early gastric cancer: Propensity score-matched analysis.

OBJECTIVES: It is unclear whether renal insufficiency (RI) itself is a risk factor for adverse outcomes after gastric endoscopic submucosal dissection (ESD). We aimed to evaluate the safety and efficacy of gastric ESD in patients with and without RI using propensity score-matching analysis. METHODS: In all, 4775 patients with 4775 early gastric cancer lesions undergoing ESD were analyzed. 1:1 propensity score-matching was performed between patients with and without RI using 12 variables. After matching, logistic regression and survival analyses were performed for short- and long-term outcomes of ESD, respectively. RESULTS: The matching yielded 188 pairs of patients with and without RI. In both univariable and multivariable analyses, the presence of RI was not significantly associated with postprocedural bleeding (unadjusted odds ratio 1.81, 95% confidence interval 0.74-4.42; adjusted odds ratio 1.86, 95% confidence interval 0.74-4.65, respectively). When RI patients were subclassified into patients with estimated glomerular filtration rate (eGFR) 30-59 mL/min/1.73 m2 and eGFR <30 mL/min/1.73 m2 , no significant differences in bleeding rates were found compared to their matched controls in both groups. Perforation, en bloc resection, en bloc and R0 resection, and curative resection rates of RI patients were 2.1%, 98.4%, 91.0%, and 78.2%, respectively, which were comparable to those of non-RI patients. During a median follow-up of 119 months, there was no difference in gastric cancer-specific survival between patients with and without RI (P = 0.143). CONCLUSION: The outcomes of ESD were comparable in patients with and without RI. Decreased renal function itself may not be a reason to keep patients with RI from receiving gastric ESD.

Korean Practice Guidelines for Gastric Cancer 2022: An Evidence-based, Multidisciplinary Approach.

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Korean practice guidelines for gastric cancer 2022: an evidence-based, multidisciplinary approach

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Outcomes of Endoscopic Resection for Early Gastric Cancer in Very Elderly Patients: A Nationwide Population-Based Study.

Background/Aims: Few studies have investigated the long-term outcomes of endoscopic resection for early gastric cancer (EGC) in very elderly patients. The aim of this study was to determine the appropriate treatment strategy and identify the risk factors for mortality in these patients. Methods: Patients with EGC who underwent endoscopic resection from 2006 to 2017 were identified using National Health Insurance Data and divided into three age groups: very elderly (≥85 years), elderly (65 to 84 years), and non-elderly (≤64 years). Their long- and short-term outcomes were compared in the three age groups, and the survival in the groups was compared with that in the control group, matched by age and sex. We also evaluated the risk factors for long- and short-term outcomes. Results: A total of 8,426 patients were included in our study: 118 very elderly, 4,583 elderly, and 3,725 non-elderly. The overall survival and cancer-specific survival rates were significantly lower in the very elderly group than in the elderly and the non-elderly groups. Congestive heart failure was negatively associated with cancer-specific survival. A significantly decreased risk for mortality was observed in all groups (p<0.001). The very elderly group had significantly higher readmission and mortality rates within 3 months of endoscopic resection than the non-elderly and elderly groups. Furthermore, the cerebrovascular disease was associated with mortality within 3 months after endoscopic resection. Conclusions: Endoscopic resection for EGC can be helpful for very elderly patients, and it may play a role in achieving overall survival comparable to that of the control group.

Interval Advanced Gastric Cancer After Negative Endoscopy.

BACKGROUND & AIMS: Esophagogastroduodenoscopy (EGD) is effective in reducing gastric cancer mortality through detection of early-stage cancer in areas with a high prevalence of gastric cancer. Although the risk of post-endoscopy advanced gastric cancer (AGC) is low, interval AGC remains a concern. We investigated the characteristics and predictors of interval AGC after negative EGD. METHODS: We included 1257 patients with gastric cancer within 6 to 36 months of a "cancer-negative" index EGD between 2005 and 2021 at a tertiary university hospital in South Korea. Observation time on the index EGD was used as a quality indicator. We compared the clinical and endoscopic characteristics and quality indicators between interval AGC and screen-detected early gastric cancer (EGC). RESULTS: Within 6 to 36 months of negative EGD, 102 AGCs (8.1%) and 1155 EGCs (91.9%) were identified. The percentage of patients with shorter observation time (<3 minutes) in the index EGD was higher in the interval AGC group than in the detected EGC group (P = .002). A multivariable analysis comparing screen-detected EGD and interval AGC was adjusted for age, sex, family history of gastric cancer, H. pylori status, endoscopic findings, and endoscopy-related factors including gastric observation time and interval time. A shorter observation time (<3 minutes) (odds ratio, 2.27; 95% confidence interval, 1.20-4.30), and interval time >2 years (odds ratio, 1.84; 95% confidence interval, 1.04-3.24) were associated with an increased risk of interval AGC. CONCLUSION: A shorter observation time during index EGD is an important predictor of interval AGC. Further, withdrawal time longer than 3 minutes may be a quality indicator for screening EGD.

[Ectopic Pancreas with Walled-off Necrosis Mimicking Malignant Submucosal Gastric Tumor].

An ectopic pancreas rarely transforms into a malignancy, and the symptoms vary from patient to patient. The most commonly observed site of an ectopic pancreas is the antrum of the stomach. A 59-year-old male patient with severe abdominal pain underwent CT. A 9.6 cm-sized well-defined exophytic huge mass with heterogenic density was located between the stomach distal antrum and duodenum. A malignant submucosal tumor was suspected because of the exophytic dirty huge mass. Initially, surgery was considered to confirm the histological evaluation. After 2 months, the abdominal pain disappeared, and the follow-up MRI scan showed a decrease in size, which contained a necrotic component inside. It was confirmed that the parenchymal tissue was the pancreas. The pathology through EUS-guided fine needle aspiration (EUS-FNA) was normal pancreatic acinar cells, smooth muscle fragments, squamous cyst, and some neutrophils (abscess). Walled-off necrosis occurs as a complication of acute pancreatitis with parenchymal tissues and surrounding tissues, but complications of ectopic pancreatitis occurred in this case. Abdominal pain due to ectopic pancreas leading to the formation of a giant abscess has been reported as a very rare case. Diagnosis through biopsy is most important when a malignant submucosal tumor is suspected. In addition, it is important to determine the clinical features, examination findings, such as EUS, CT, and MRI, and the changes according to the follow-up period. This paper reports a case of ectopic pancreas, resulting in necrotic tissue and walled-off necrosis, abdominal pain, and spontaneous improvement.

Utility of a deep learning model and a clinical model for predicting bleeding after endoscopic submucosal dissection in patients with early gastric cancer.

BACKGROUND: Bleeding is one of the major complications after endoscopic submucosal dissection (ESD) in early gastric cancer (EGC) patients. There are limited studies on estimating the bleeding risk after ESD using an artificial intelligence system. AIM: To derivate and verify the performance of the deep learning model and the clinical model for predicting bleeding risk after ESD in EGC patients. METHODS: Patients with EGC who underwent ESD between January 2010 and June 2020 at the Samsung Medical Center were enrolled, and post-ESD bleeding (PEB) was investigated retrospectively. We split the entire cohort into a development set (80%) and a validation set (20%). The deep learning and clinical model were built on the development set and tested in the validation set. The performance of the deep learning model and the clinical model were compared using the area under the curve and the stratification of bleeding risk after ESD. RESULTS: A total of 5629 patients were included, and PEB occurred in 325 patients. The area under the curve for predicting PEB was 0.71 (95% confidence interval: 0.63-0.78) in the deep learning model and 0.70 (95% confidence interval: 0.62-0.77) in the clinical model, without significant difference (P = 0.730). The patients expected to the low- (< 5%), intermediate- (≥ 5%, < 9%), and high-risk (≥ 9%) categories were observed with actual bleeding rate of 2.2%, 3.9%, and 11.6%, respectively, in the deep learning model; 4.0%, 8.8%, and 18.2%, respectively, in the clinical model. CONCLUSION: A deep learning model can predict and stratify the bleeding risk after ESD in patients with EGC.

The effects of oral steroid duration on stricture prevention after extensive endoscopic submucosal dissection for superficial esophageal cancer.

Background: Esophageal stricture is a major complication of endoscopic submucosal dissection (ESD) in patients with superficial esophageal cancer (SEC). Oral steroids have been used to prevent esophageal stricture in patients with more than 75% of the esophageal circumference resected. However, there are no established guidelines regarding the optimal duration of steroid use. This retrospective observational study aimed to compare the incidence of esophageal stricture according to the period of prophylactic oral steroid use and to identify the risk factors for esophageal stricture. Methods: Eighty-one patients who were prescribed prophylactic steroid after undergoing ESD for SEC with more than 75% of esophageal circumference resected were enrolled. Patients were classified into the four-week steroid group (n=72) or eight-week steroid group (n=9) to compare the incidence of esophageal stricture. In addition, the patients were subdivided into those who developed esophageal stricture (n=24) and those who did not (n=57) to identify the risk factors for esophageal stricture. Results: Twenty patients (27.8%) in the four-week oral steroid group and four patients (44.4%) in the eight-week oral steroid group developed esophageal stricture (P=0.44). The univariable analysis identified tumor size, longitudinal length of semi-circumferential resection, and proportion of circumferential resection as risk factors of esophageal stricture. The multivariable analysis identified the proportion of circumferential resection as an independent risk factor. After adjusting for the proportion of circumferential resection, the incidence of stricture was marginally higher in the eight-week steroid group [P=0.05; odds ratio (OR): 5.69; 95% confidence interval (CI): 1.01-32.15]. Conclusions: Eight weeks of oral steroid prophylaxis does not reduce the risk of stricture after extensive ESD more than four weeks of oral steroid prophylaxis. The proportion of circumferential resection is the strongest risk factor for stricture in patients with SEC undergoing ESD.

Machine Learning Model to Stratify the Risk of Lymph Node Metastasis for Early Gastric Cancer: A Single-Center Cohort Study.

Stratification of the risk of lymph node metastasis (LNM) in patients with non-curative resection after endoscopic resection (ER) for early gastric cancer (EGC) is crucial in determining additional treatment strategies and preventing unnecessary surgery. Hence, we developed a machine learning (ML) model and validated its performance for the stratification of LNM risk in patients with EGC. We enrolled patients who underwent primary surgery or additional surgery after ER for EGC between May 2005 and March 2021. Additionally, patients who underwent ER alone for EGC between May 2005 and March 2016 and were followed up for at least 5 years were included. The ML model was built based on a development set (70%) using logistic regression, random forest (RF), and support vector machine (SVM) analyses and assessed in a validation set (30%). In the validation set, LNM was found in 337 of 4428 patients (7.6%). Among the total patients, the area under the receiver operating characteristic (AUROC) for predicting LNM risk was 0.86 in the logistic regression, 0.85 in RF, and 0.86 in SVM analyses; in patients with initial ER, AUROC for predicting LNM risk was 0.90 in the logistic regression, 0.88 in RF, and 0.89 in SVM analyses. The ML model could stratify the LNM risk into very low (<1%), low (<3%), intermediate (<7%), and high (≥7%) risk categories, which was comparable with actual LNM rates. We demonstrate that the ML model can be used to identify LNM risk. However, this tool requires further validation in EGC patients with non-curative resection after ER for actual application.

Clinical characteristics and treatment outcomes of primary malignant melanoma of esophagus: a single center experience.

BACKGROUND: Primary malignant melanoma of esophagus (PMME) is an extremely rare disease with poor prognosis. We aimed to determine the clinical characteristics and treatment outcomes of patients with PMME. METHODS: We retrospectively reviewed 17 patients diagnosed with PMME in Samsung Medical Center between 2000 and 2020 with median 34 months of follow-up. Survival outcomes were analyzed with Kaplan-Meier method. RESULTS: 15 patients (88.2%) were male and the most common presenting symptom was dysphagia (9/17, 52.9%). On endoscopy, tumors were mass-forming in 15 patients (88.2%) and diffusely infiltrative in two patients (11.8%). Lesions were melanotic in 13 patients (76.5%) and amelanotic in four patients (23.5%). The most common tumor location was lower esophagus (11/17, 64.7%). The disease was metastatic at the time of diagnosis in four patients (23.5%). As for treatment, 10 patients (58.8%) underwent surgery. In all 17 patients, the median overall survival was 10 months. In surgically treated patients, all patients experienced recurrence and the median disease-free survival was 4 months. There was no statistical difference in overall survival between patients with or without surgery. Patients with diffusely infiltrative tumor morphology had better overall survival compared to those with mass-forming tumor morphology (P = 0.048). Two patients who received immunotherapy as the first-line treatment without surgery showed overall survival of 34 and 18 months, respectively. CONCLUSIONS: As radical resection for patients with PMME does not guarantee favorable treatment outcomes, novel treatment strategy is required. Further large-scale studies are warranted to determine the efficacy of immunotherapy for patients with PMME.

A preoperative risk prediction model for high malignancy potential gastrointestinal stromal tumors of the stomach.

BACKGROUND: Gastric gastrointestinal stromal tumors (GISTs) exhibit various degrees of aggression and malignant potential. However, no systematic preoperative evaluation strategy to predict the malignancy potential of gastric GISTs has yet been developed. This study aimed to develop a reliable and easy-to-use preoperative risk-scoring model for predicting high malignancy potential (HMP) gastric GISTs. METHODS: The data of 542 patients with pathologically confirmed gastric GISTs who underwent resection were reviewed. Multivariate logistic regression analysis was used to identify significant predictors of HMP. The risk-scoring system (RSS) was based on the predictive factors for HMP, and its performance was validated using a split-sample approach. RESULTS: A total of 239 of 542 (44.1%) surgically resected gastric GISTs had HMP. Multivariate analysis demonstrated that tumor size, location, and surface changes were independent risk factors for HMP. Based on the accordant regression coefficients, the presence of surface ulceration was assigned 1 point. Tumor sizes of 4-6 cm and > 6 cm were assigned 2 and 5 points, respectively. Two points were assigned to cardia or fundus locations. A score of 3 points was the optimal cut-off value for HMP prediction. HMP were found in 19.8% and 82.7% of the low and high-risk groups of the RSS, respectively. The area under the receiver-operating characteristic curve for predicting HMP was 0.81 (95% confidence interval (CI) 0.75-0.86). Discrimination was good after validation (0.75, 95% CI 0.69-0.81). CONCLUSION: This simple RSS could be useful for predicting the malignancy potential of gastric GISTs and may aid preoperative clinical decision making to ensure optimal treatment.

Clinical Outcomes and Adverse Events of Gastric Endoscopic Submucosal Dissection of the Mid to Upper Stomach under General Anesthesia and Monitored Anesthetic Care.

BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD) of gastric tumors in the mid-to-upper stomach is a technically challenging procedure. This study compared the therapeutic outcomes and adverse events of ESD of tumors in the mid-to-upper stomach performed under general anesthesia (GA) or monitored anesthesia care (MAC). METHODS: Between 2012 and 2018, 674 patients underwent ESD for gastric tumors in the midbody, high body, fundus, or cardia (100 patients received GA; 574 received MAC). The outcomes of the propensity score (PS)-matched (1:1) patients receiving either GA or MAC were analyzed. RESULTS: The PS matching identified 94 patients who received GA and 94 patients who received MAC. Both groups showed high rates of en bloc resection (GA, 95.7%; MAC, 97.9%; p=0.68) and complete resection (GA, 81.9%; MAC, 84.0%; p=0.14). There were no significant differences between the rates of adverse events (GA, 16.0%; MAC, 8.5%; p=0.18) in the anesthetic groups. Logistic regression analysis indicated that the method of anesthesia did not affect the rates of complete resection or adverse events. CONCLUSION: ESD of tumors in the mid-to-upper stomach at our high-volume center had good outcomes, regardless of the method of anesthesia. Our results demonstrate no differences between the efficacies and safety of ESD performed under MAC and GA.

Long-term Outcomes of Additional Endoscopic Treatments for Patients with Positive Lateral Margins after Endoscopic Submucosal Dissection for Early Gastric Cancer.

Background/Aims: It is uncertain whether additional endoscopic treatment may be chosen over surgery in patients with positive lateral margins (pLMs) as the only non-curative factor after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). We aimed to compare the long-term outcomes of additional endoscopic treatments in such patients with those of surgery and elucidate the clinicopathological factors that could influence the treatment selection. Methods: A total of 99 patients with 101 EGC lesions undergoing additional treatment after noncurative ESD with pLMs as the only non-curative factor were analyzed. Among them, 25 (27 lesions) underwent ESD, 29 (29 lesions) underwent argon plasma coagulation (APC), and 45 (45 lesions) underwent surgery. Clinicopathological characteristics and long-term outcomes were compared. Results: Residual tumor was found in 73.6% of cases. The presence of multiple pLMs was associated with higher risk of residual tumor (p=0.046). During a median follow-up of 58.9 months, recurrent or residual lesions after additional ESD and APC were found in 4% (1/25) and 6.8% (2/29) of patients, respectively. However, all were completely cured with surgery or repeated ESD. There were no extragastric recurrences after additional endoscopic treatment. Lymph node metastasis was identified after additional surgery in one (2.2%) patient with an EGC showing histological heterogeneity. Conclusions: Given the favorable long-term outcomes, additional ESD or APC may be an acceptable choice for patients with pLMs as the only non-curative factor after ESD for EGC. However, clincopathological characteristics such as multiple pLMs and histological heterogeneity should be considered in the treatment selection.

Long-term outcomes of endoscopic resection followed by additional surgery after non-curative resection in undifferentiated-type early gastric cancer: a nationwide multi-center study.

BACKGROUND: Undifferentiated-type early gastric cancer (UD EGC) shows lower curative resection rates after endoscopic submucosal dissection (ESD). Additional surgery is recommended after non-curative resection. We evaluated the long-term outcomes of ESD followed by additional surgery after non-curative resection in UD EGC compared to those for surgery as initial treatment. METHODS: We reviewed 1139 UD EGC patients who underwent ESD at 18 hospitals and 1956 patients who underwent surgery at two hospitals between February 2005 and May 2015. We enrolled 636 patients with non-curative ESD and 1429 surgery subjects beyond the curative ESD criteria. Among them, 133 patients with additional surgery after ESD (ESD + OP group) and 252 patients without additional surgery (ESD-only group) were matched 1:1 using propensity scores to patients with surgery as initial treatment (surgery group). Overall survival (OS) and recurrence-free survival (RFS) were compared. RESULTS: Signet ring cell carcinoma and poorly differentiated adenocarcinoma (PDA) were observed in 939 and 1126 cases, respectively. OS was significantly longer in the surgery group than in the ESD + OP group, especially for PDA. However, RFS was shorter in the ESD-only group than those in the ESD + OP and surgery groups. RFS did not differ significantly between the ESD + OP and surgery groups. Compared to the surgery group, the ESD-only and ESD + OP groups had an overall hazard ratio for RFS of 3.58 (95% confidence interval 1.44-8.88) and 0.46 (0.10-2.20), respectively. CONCLUSIONS: ESD followed by additional surgery after non-curative resection showed comparable cancer-specific outcomes to initial surgery in UD EGC.

Increased Risk of Diabetes after Definitive Radiotherapy in Patients with Indolent Gastroduodenal Lymphoma.

PURPOSE: This study aimed to evaluate the effect of radiotherapy (RT) on the risk of diabetes by assessing hemoglobin A1c (HbA1c) levels in patients with gastroduodenal indolent lymphoma. MATERIALS AND METHODS: This retrospective study included patients with stage I extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue or follicular lymphoma of the gastroduodenal region who were treated with Helicobacter pylori eradication and/or RT between 2000 and 2019 in our institution. Of total 79 patients with HbA1c test, 17 patients received RT (RT group), while 62 patients did not receive RT (control group). A diabetes-associated event (DAE) was defined as a ≥ 0.5% increase in HbA1c levels from baseline, and diabetes event (DE) were defined as HbA1c level of ≥ 6.5%. RESULTS: During the median follow-up of 49 months, no local failure occurred after RT and no patients died of lymphoma. The RT group had significantly higher risk for DAEs on univariable analysis (hazard ratio [HR], 4.18; 95% confidence interval [CI], 1.64 to 10.66; p < 0.01) and multivariable analysis (HR, 3.68; 95% CI, 1.42 to 9.56; p=0.01). Further, the DE risk was significantly higher in the RT group than in the control group (HR, 4.32; 95% CI, 1.08 to 17.30; p=0.04) and in patients with increased baseline HbA1c levels (HR, 35.83; 95% CI, 2.80 to 459.19; p=0.01). On multivariable analysis, RT significantly increased the risk of DEs (HR, 4.55; 95% CI, 1.08 to 19.19; p=0.04), even after adjusting baseline HbA1c level (HR, 40.97; 95% CI, 3.06 to 548.01; p=0.01). CONCLUSION: Patients who received RT for gastroduodenal indolent lymphoma had an increased risk of diabetes compared to those who did not.