Endoscopic Submucosal Dissection for Treatment of Localized Gastric Mucosa-Associated Lymphoid Tissue Lymphoma: A Case Series

Background/Aims@#The treatment for gastric mucosa-associated lymphoid tissue lymphoma (MALToma) generally involves eradication of Helicobacter pylori. However, MALToma lesions may recur even without H. pylori re-infection. Furthermore, the remission rate of H. pylori-negative MALToma after eradication is low. Therefore, herein, we report on endoscopic submucosal dissection (ESD) as a treatment strategy for gastric MALToma. @*Methods@#We retrospectively reviewed the data of all patients of gastric MALToma who underwent endoscopic resection at our institution between January 2000 and December 2021. Clinical remission was defined as complete histological remission or probable minimal residual disease according to the GELA grading system for post-treatment evaluation of gastric MALToma. @*Results@#Six patients with gastric MALToma underwent ESD. Two patients were diagnosed with gastric MALToma, which improved after eradication treatment and relapsed approximately 36 and 41 months later, respectively. These patients had singular lesions localized to the mucosa and did not experience H. pylori re-infection. The lesions were successfully removed via ESD. The remaining four patients had H. pylori-negative gastric MALToma. These patients also had single, localized lesions that were removed via ESD. All the patients remained in clinical remission until the final follow-up. @*Conclusions@#ESD is a safe and effective intervention for H. pylori-negative gastric MALToma when the lesion is single and confined to the mucosal layer.

Comparison of Helicobacter pylori Eradication Rates Using Standard Triple Therapy and Sequential Therapy

Objectives@#The incidence of treatment failures following standard triple therapy (STT) for Helicobacter pylori eradication (HPE) has reached an unacceptable level. Sequential therapy (SQ) has emerged as a promising approach to counteract the escalation of antibiotic resistance. In this study, we used a chronological cohort dataset to conduct a comparative analysis of the eradication rates, compliance, and adverse events associated with the 7-day STT and SQ. @*Methods@#A total of 789 patients underwent HPE treatment at Asan Medical Center between July 2013 and August 2017. Among them, 378 received a 7-day STT and 411 received a 10-day SQ. Baseline clinical data and treatment parameters were compared between the two treatment groups. @*Results@#SQ demonstrated an eradication rate of 84.7% (348/411), which was superior to that of the 7-day STT (74.1%; p<0.001). The incidence of adverse events was also higher in the SQ group than in the STT group (17.5% vs. 11.1%; p=0.01). Nonetheless, treatment compliance was not significantly different between the groups (98.1% [SQ] vs. 96.8% [STT]; p=0.38). Among the patients undergoing second-line eradication, the SQ group displayed a lower eradication rate than the STT group (77.8% vs. 92.4%; p=0.028). Notably, the overall eradication rate did not differ significantly between the two groups (98.3% [STT] vs. 97.4% [SQ]; p=0.56). @*Conclusions@#SQ exhibited superior efficacy compared with the 7-day STT as a first-line H. pylori treatment. Thus, SQ holds potential to serve as the replacement for the 7-day STT in treatment-naïve patients.

Comparison of Diagnosis of Esophageal Motility Disorders by Chicago Classification Versions 3.0 and 4.0

Background/Aims@#We aim to investigate the diagnostic accuracy and differences between Chicago classification version 3.0 (CC v3.0) and 4.0 (CC v4.0). @*Methods@#Patients who underwent high-resolution esophageal manometry (HRM) for suspected esophageal motility disorders were prospectively recruited between May 2020 and February 2021. The protocol of HRM studies included additional positional change and provocative testing designed by CC v4.0. @*Results@#Two hundred forty-four patients were included. The median age was 59 (interquartile range, 45-66) years, and 46.7% were males.Of these, 53.3% (n = 130) and 61.9% (n = 151) were categorized as normalcy by CC v3.0 and CC v4.0, respectively. The 15 patients diagnosed of esophagogastric junction outflow obstruction (EGJOO) by CC v3.0 was changed to normalcy by position (n = 2) and symptom (n = 13) by CC v4.0. In seven patients, the ineffective esophageal motility (IEM) diagnosis by CC v3.0 was changed to normalcy by CC v4.0. The diagnostic rate of achalasia increased from 11.1% (n = 27) to 13.9% (n = 34) by CC v4.0. Of patients diagnosed IEM by CC v3.0, 4 was changed to achalasia based on the functional lumen imaging probe (FLIP) results by CC v4.0. Three patients (2 with absent contractility and 1 with IEM in CC v3.0) were newly diagnosed with achalasia using a provocative test and barium esophagography by CC v4.0. @*Conclusions@#CC v4.0 is more rigorous than CC v3.0 for the diagnosis of EGJOO and IEM and diagnoses achalasia more accurately by using provocative tests and FLIP. Further studies on the treatment outcomes following diagnosis with CC v4.0 are needed.

Usefulness of EndoFLIP in Diverticular Peroral Endoscopic Myotomy for Symptomatic Epiphrenic Diverticulum

Background/Aims@#Diverticular peroral endoscopic myotomy (D-POEM) is known to be a safe and feasible technique for managing diverticular diseases of the esophagus. In this study, we aim to report our experience with D-POEM and to investigate the usefulness of endoscopic functional luminal imaging probe (EndoFLIP) in determining the need for cardiomyotomy with septotomy for symptomatic epiphrenic diverticulum. @*Methods@#Consecutive patients who underwent D-POEM for symptomatic epiphrenic diverticulum between September 2019 and September 2021 were eligible for this study. EndoFLIP and high-resolution manometry results and endoscopic treatment outcomes were retrospectively investigated. @*Results@#A total of 9 patients with symptomatic epiphrenic diverticulum were included. The median size of the diverticulum and septum was 50 (interquartile range [IQR], 48-80) mm and 20 (IQR, 20-30) mm, respectively. The overall technical success rate was 100%, with a median procedure time of 60 (IQR, 46-100) minutes. The 5 patients (high-resolution manometry results; 3 normal, 1 ineffective esophageal motility, and 1 Jackhammer esophagus) who had decreased esophagogastric junction distensibility index on pre-procedure EndoFLIP underwent cardiomyotomy with septotomy regardless of the presence of esophageal motility disorders, and the distensibility index increased and normalized after procedure. The mean dysphagia score decreased from 2.0 ± 1.0 pre-procedure to 0.4 ± 0.7 during a median follow-up of 11 (IQR, 4-21) months post-procedure. No serious adverse events that required surgical intervention or delayed discharge were noted. @*Conclusions@#EndoFLIP may help decide whether to perform combined cardiomyotomy and septotomy for the treatment of an epiphrenic diverticulum. Further large-scale studies are needed to confirm these results.

Incidence, Morbidity, and Mortality of Achalasia: A Nationwide, Population-Based Cohort Study in South Korea

Background/Aims@#Although an association between achalasia and esophageal cancer has been reported, whether achalasia confers a substantial increase in mortality is unknown. Moreover, the causes of death related to achalasia have not been investigated. We performed this nationwide, population-based cohort study on achalasia because no such study has been performed since the introduction of high-resolution manometry in 2008. @*Methods@#This study was performed using data extracted from the Korean National Health Insurance Service database, covering a 9-year period from 2009 to 2017. Control participants without a diagnostic code for achalasia were randomly selected and matched by sex and birth year at a case-to-control ratio of 1:4. Data on the cause of death from Statistics Korea were also analyzed. @*Results@#The overall incidence of achalasia was 0.68 per 100,000 person-years, and the prevalence was 6.46 per 100,000 population. Patients with achalasia (n=3,063) had significantly higher adjusted hazard ratio (aHR) for esophageal cancer (aHR, 3.40; 95% confidence interval [CI], 1.25 to 9.22; p=0.017), pneumonia (aHR, 2.30; 95% CI, 1.89 to 2.81; p<0.001), aspiration pneumonia (aHR, 3.92; 95% CI, 2.38 to 6.48; p<0.001), and mortality (aHR, 1.68; 95% CI, 1.44 to 1.94; p<0.001). Esophageal cancer carried the highest mortality risk (aHR, 8.82; 95% CI, 2.35 to 33.16; p=0.001), while pneumonia had the highest non-cancer mortality risk (aHR, 2.28; 95% CI, 1.31 to 3.96; p=0.004). @*Conclusions@#In this nationwide study, achalasia was associated with increased risk of mortality.Esophageal cancer and pneumonia were the most common comorbidities and the major causes of death in patients with achalasia.

Real-Time Polymerase Chain Reaction for the Detection of Helicobacter pylori and Clarithromycin Resistance

Background/Aims@#Real-time polymerase chain reaction (RT-PCR) is a fast and simple method for the simultaneous detection of clarithromycin (CLR) resistance and Helicobacter pylori. We evaluated the effectiveness of RT-PCR compared to that of the rapid urease test (RUT) and assessed its value in verifying CLR resistance. @*Methods@#A total of 70 specimens with confirmed H. pylori infection in culture were enrolled and analyzed in this prospective study. All specimens were subjected to RT-PCR assay using fluorescence melting peak signals to detect H. pylori infection and CLR resistances caused by either A2142G or A2143G mutations in the 23S ribosomal RNA gene (23S rRNA). The results were compared to those of RUT and antimicrobial susceptibility culturing tests to investigate the efficacy of RT-PCR. @*Results@#Among the 70 specimens analyzed, the positivity rate was 97.1% (68/70) with RT-PCR and 82.9% (58/70) with RUT. CLR resistance (minimum inhibitory concentration >1.0 μg/mL) was confirmed in 18.6% (13/70), and fluorescence melting curve analysis showed that 84.6% (11/13) had point mutations in 23S rRNA. Ten specimens had only A2143G mutation, and one specimen contained both A2142G and A2143G mutations. @*Conclusions@#RT-PCR assay was found to be more efficient than RUT in detecting H. pylori infection and could effectively verify CLR resistance compared to the antimicrobial susceptibility culturing test. Considering the high sensitivity and accessibility of RT-PCR method, it could be used to easily detect CLR-resistant H. pylori, thus helping clinicians select suitable treatment regimen and improve the eradication rate.

Clinical Significance of Epstein-Barr Virus and Helicobacter pylori Infection in Gastric Carcinoma

Background/Aims@#Epstein-Barr virus (EBV) and Helicobacter pylori (HP) coinfection may synergistically induce severe inflammatory responses in the stomach tissue, increasing the risk of developing gastric cancer. We aimed to analyze the effect of EBV and HP coinfection on the clinicopathologic features and prognosis of gastric cancer, as well as to evaluate the role of EBV infection in non-gastric carcinoma with lymphoid stroma (non-GCLS). @*Methods@#Overall, 956 patients who underwent surgery for gastric cancer between September 2014 and August 2015 were eligible and divided into groups, according to GCLS morphology, EBV infection, and HP infection. Clinicopathologic characteristics and oncologic outcomes were analyzed retrospectively. @*Results@#EBV and HP coinfection was significantly associated with male sex, proximal location, GCLS morphology, and equivocal p53 expression (p<0.001). Multivariate analysis revealed that EBV infection alone (hazard ratio [HR], 0.362; 95% CI, 0.131 to 0.996; p=0.049) and lower third location (HR, 0.624; 95% CI, 0.413 to 0.943; p=0.025) were inversely correlated with overall survival. During median follow-up period of 72 months, overall survival rate was not significantly different between the EBV and HP coinfection group and others (97.6% vs 86.8%, log-rank p=0.144). In non-GCLS patients (n=920), overall survival rate was not significantly different between the EBV infection group and others (96.9% vs 86.4%, log-rank p=0.126). @*Conclusions@#EBV and HP coinfection is not an independent prognostic factor for gastric cancer. EBV infection status, regardless of HP infection, affects the clinicopathologic features of all types of gastric cancer. However, it does not lead to a significant difference in overall survival of nonGCLS patients.

The Predictive Value of Intraoperative Esophageal Functional Luminal Imaging Probe Panometry in Patients With Achalasia Undergoing Peroral Endoscopic Myotomy: A Single-center Experience

Background/Aims@#We evaluated the clinical significance and prognostic power of functional luminal imaging probe (FLIP) panometry in patients with achalasia treated with peroral endoscopic myotomy (POEM), and examined the clinical parameters associated with symptomatic improvement and the presence of contractility (POC) following POEM. @*Methods@#We reviewed the electronic medical records of patients with achalasia treated with FLIP panometry and POEM at a tertiary teaching hospital in Seoul, Republic of Korea. Follow-up examination was composed of esophageal manometry and questionnaires on symptoms. We analyzed the FLIP data by interpolating using the cubic spline method in MATLAB. @*Results@#We retrospectively analyzed 33 men and 35 women (mean age: 52 ± 17 years), of whom 14, 39, and 15 patients were diagnosed with achalasia types I, II, and III, respectively. The FLIP panometry diagnoses were reduced esophagogastric junction opening (REO) with a retrograde contractile response (n = 43); REO with an absent contractile response (n = 5); REO with a normal contractile response (n = 11); and a retrograde contractile response (n = 9). Overall, the patients showed improvements in Eckardt scores following POEM from 6.48 ± 2.20 to 1.16 ± 1.15 (P < 0.01). Post-POEM symptomatic improvement was not significantly associated with any of the clinical parameters, including panometry diagnosis. Conversely, post-POEM POC was significantly associated with the presence of repetitive antegrade contractions and achalasia subtypes (both P < 0.01). @*Conclusion@#While FLIP panometry was not significantly associated with the clinical course of achalasia, FLIP panometry was associated with POC following POEM and may complement manometry in the functional evaluation of esophageal motility disorders.

Natural History of Asymptomatic Esophageal Subepithelial Tumors of 30mm or Less in Size

Background@#No definite guidelines for the management of small esophageal subepithelial tumors (SETs) have been established, because there are limited data and studies on their natural history. We aimed to assess the natural history and propose optimal management strategies for small esophageal SETs. @*Methods@#Patients diagnosed as esophageal SETs ≤ 30 mm in size between 2003 and 2017 using endoscopic ultrasound (EUS) with a minimal follow-up of 3 months were enrolled, and their esophagogastroduodenoscopy (EGD) and EUS were retrospectively reviewed. @*Results@#Of 275 esophageal SETs in 262 patients, the initial size was < 10 mm, 10–20 mm, and 20–30 mm in 104 (37.8%), 105 (38.2%), and 66 (24.0%) lesions, respectively. Only 22 (8.0%) SETs showed significant changes in size and/or echogenicity and/or morphology at a median of 40 months (range, 4–120 months). Tissues of 6 SETs showing interval changes were obtained using EUS-guided fine needle aspiration biopsy; 1 was identified as a gastrointestinal stromal tumor (GIST) and was surgically resected, while the other 5 were leiomyomas and were regularly observed. Eight SETs showing interval changes were resected surgically or endoscopically without pathological confirmation; 1 was a GIST, 2 were granular cell tumors, and the other 5 were leiomyomas. @*Conclusion@#Regular follow-up with EGD or EUS may be necessary for esophageal SETs ≤ 30 mm in size considering that small portion of them has a possibility of malignant potential. When esophageal SETs ≤ 30 mm show significant interval changes, pathological confirmation may precede treatment to avoid unnecessary resection.

Outcomes of endoscopic submucosal dissection for superficial esophageal neoplasms in patients with liver cirrhosis

Background/Aims@#The treatment of superficial esophageal neoplasms (SENs) in cirrhotic patients is challenging and rarely investigated. We evaluated the outcomes of endoscopic submucosal dissection (ESD) to determine the efficacy and safety of treating SENs in patients with liver cirrhosis. @*Methods@#The baseline characteristics and treatment outcomes of patients who underwent ESD for SENs between November 2005 and December 2017 were retrospectively reviewed. @*Results@#ESD was performed in 437 patients with 481 SENs, including 15 cirrhotic patients with 17 SENs. En bloc resection (88.2% vs. 97.0%) and curative resection (64.7% vs. 78.9%) rates were not different between the cirrhosis and non-cirrhosis groups (p=0.105 and p=0.224, respectively). Bleeding was more common in cirrhotic patients (p=0.054), and all cases were successfully controlled endoscopically. The median procedure and hospitalization duration did not differ between the groups. Overall survival was lower in cirrhotic patients (p=0.003), while disease-specific survival did not differ between the groups (p=0.85). @*Conclusions@#ESD could be a safe and effective treatment option for SENs in patients with cirrhosis. Detailed preprocedural assessments are needed, including determination of liver function, esophageal varix status, and remaining life expectancy, to identify patients who will obtain the greatest benefit.

Effect of Antithrombotic Therapy on Bleeding after Argon Plasma Coagulation for Gastric Neoplasms

Background/Aims@#Postprocedural bleeding is known to be relatively low after argon plasma coagulation (APC) for gastric neoplasms; however, there are few studies proving the effect of antithrombotic agents. This study aimed to analyze the incidence of delayed bleeding (DB) based on antithrombotic agents administered and to identify the risk factors for DB in APC for gastric tumors. @*Methods@#A total of 785 patients with 824 lesions underwent APC for single gastric neoplasm between January 2011 and January 2018. After exclusion, 719 and 102 lesions were classified as belonging to the non-antithrombotics (non-AT) and AT groups, respectively. The clinical outcomes were compared between the two groups, and we determined the risk factors for DB in gastric APC. @*Results@#Of the total 821 cases, DB occurred in 20 cases (2.4%): 17 cases in the non-AT group and three cases in the AT group (2.4% vs 2.9%, p=0.728). Multivariate analysis of the risk factors for DB confirmed the following significant, independent risk factors: male sex (odds ratio, 7.66; 95% confidence interval, 1.02 to 57.69; p=0.048) and chronic kidney disease (odds ratio, 4.51; 95% confidence interval, 1.57 to 13.02; p=0.005). Thromboembolic events and perforation were not observed in all patients regardless of whether they took AT agents. @*Conclusions@#AT therapy is acceptably safe in gastric APC because it does not significantly increase the incidence of DB. However, patients with chronic kidney disease or male sex need to receive careful follow-up on the incidence of post-APC bleeding.

Is Ex Vivo Training before In Vivo Training Effective in Learning Gastric Endoscopic Submucosal Dissection?

Background/Aims@#The learning curve is essential in endoscopic submucosal dissection (ESD) training to improve outcomes and reduce the risk of procedure-related complications. We compared the outcomes of gastric ESD in live pigs performed by inexperienced endoscopists with or without ex vivo training. @*Materials and Methods@#At the Olympus Medical Training and Education Center, nine endoscopists inexperienced in ESD were randomly divided into two groups (group A: ex vivo training followed by in vivo training; group B: in vivo training only), and they performed gastric ESDs. @*Results@#A total of 18 ESDs were performed. The en bloc resection rate was 88.9% (16/18), and the complete resection rate was 94.4% (17/18). The median specimen size was 2.5 cm in group A and 2.1 cm in group B (P=0.227). There was no significant difference in the procedure time between the two groups, except for the marking time (0′58″ vs. 2′58″, P=0.027). However, group A took a shorter time in dissecting the same area than group B (109 vs. 246 sec/cm2, P=0.083). Complication rates were not significantly different between both groups. @*Conclusions@#The procedure time during in vivo ESD training in pigs may be shortened by prior ex vivo training. However, the ex vivo model presented poor air inflation, unstable fixation, and excessive mucosal hardness for cutting. An advanced simulator or sufficient ex vivo training may be effective in training for the ESD procedure.

Predictive Role of Endoscopic Surveillance after Total Gastrectomy with R0 Resection for Gastric Cancer

Background@#Endoscopic surveillance after total gastrectomy (TG) for gastric cancer is routinely performed to detect tumor recurrence and postoperative adverse events.However, the reports on the clinical benefits of endoscopic surveillance are ambiguous. We investigated the clinical benefit of endoscopic surveillance after TG for gastric cancer. @*Methods@#We analyzed 848 patients who underwent TG with R0 resection for gastric cancer between 2011 and 2012 (380 early gastric cancer and 468 advanced gastric cancer) and underwent regular postoperative surveillance with endoscopy and abdominopelvic computed tomography (CT) with contrast. @*Results@#Median follow-up periods were 58 months for both endoscopy (range, 3–96) and abdominopelvic CT (range, 1–96). Tumor recurrence occurred in 167 patients (19.7%), of whom seven (4.2%) were locoregional recurrences in the peri-anastomotic area (n = 5) or regional gastric lymph nodes (n = 2). Whereas the peri-anastomotic recurrences were detected by both endoscopy and abdominopelvic CT, regional lymph node recurrences were only detected by abdominopelvic CT. Out of the 23 events of postoperative adverse events, the majority (87%) were detected by radiologic examinations; three events of benign strictures in the anastomotic site were detected only by endoscopy. @*Conclusion@#Endoscopic surveillance did not have a significant role in detecting locoregional tumor recurrence and postoperative adverse events after TG with R0 resection for gastric cancer. Routine endoscopic surveillance after TG may be considered optional and performed according to the capacities of each clinical setting.

Long-term Outcomes and Factors Affecting the Survival of Patients with Mucosal Esophageal Squamous Cell Carcinoma

Background/Aims@#Data regarding the prognosis of early esophageal cancer are lacking. This study investigated the long-term outcomes and factors affecting the survival of patients with mucosal esophageal squamous cell carcinoma (T1aESCC). @*Methods@#We analyzed the clinical and tumor-specific parameters of 263 patients who received surgical resection (SR; n=63) or endoscopic resection (ER; n=200) for T1aESCC. Underlying comorbidities were scored using the Charlson comorbidity index (CCI). Overall survival (OS) was the primary outcome, and multivariate regression analysis was performed to predict factors for OS. @*Results@#Of the study patients (age, 64.5±8.0 years), the CCI was 1.0±1.4 in the ER group and 0.6±0.9 in the SR group (p=0.107). The 5-year OS rate during follow-up (54.4±20.4 months) was 85.7% (ER group, 86.8%; SR group, 82.4%; p=0.631). The cumulative 5-year incidence of esophageal cancer recurrence was 10.5% in the ER group (vs 0% in the SR group). The overall mortality rate was 12.9% (ER group, 12.0%; SR group, 15.9%; p=0.399). The most common cause of mortality was second primary cancers in the ER group (75%) and organ dysfunction or postoperative complications in the SR group (70%). According to multivariate analysis, only CCI was significantly associated with OS (p2 and in those with a CCI ≤2 was 60.2% and 88.2%, respectively (p<0.001). The treatment method (ER vs SR) was not a significant affecting factor (p=0.238). @*Conclusions@#The long-term prognosis of patients with T1aESCC was significantly associated with underlying comorbidities.

Associations of Serum Lipid Level with Gastric Cancer Risk, Pathology, and Prognosis / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The association of serum lipids with gastric cancer is controversial. We clarified the role of serum lipids in the development, progression, and prognosis of gastric cancer. @*Materials and Methods@#In total, 412 patients diagnosed with gastric cancer were prospectively recruited, and 2,934 control subjects who underwent screening endoscopy were enrolled from December 2013 to March 2017 to conduct a case-control study in a tertiary center. Serum lipid profiles, including total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), apolipoprotein A-I (apoA-I), and apolipoprotein B, and clinicopathologic characteristics were analyzed. @*Results@#The gastric cancer group showed significantly lower HDL-C, higher LDL-C, and lower apoA-I level than the control group. In multivariate analysis, old age (odds ratio [OR], 1.051; p < 0.001), smoking (OR, 1.337; p < 0.001), a family history of gastric cancer (OR, 2.038; p < 0.001), Helicobacter pylori seropositivity (OR, 4.240; p < 0.001), lower HDL-C (OR, 0.712; p=0.020), and higher LDL-C (p=0.002) were significant risk factors for gastric cancer. Lower HDL-C and higher LDL-C remained significant after adjustments for covariates, including age and sex. In a subgroup analysis of the gastric cancer group, lower TG levels were associated with undifferentiated histology. No serum lipids were associated with overall survival. @*Conclusion@#Lower HDL-C and higher LDL-C were associated with the risk of gastric cancer, even after adjusting for age, sex, and other factors. In the gastric cancer group, undifferentiated histology was associated with lower TG levels.

Is Ex Vivo Training before In Vivo Training Effective in Learning Gastric Endoscopic Submucosal Dissection?

Background/Aims@#The learning curve is essential in endoscopic submucosal dissection (ESD) training to improve outcomes and reduce the risk of procedure-related complications. We compared the outcomes of gastric ESD in live pigs performed by inexperienced endoscopists with or without ex vivo training. @*Materials and Methods@#At the Olympus Medical Training and Education Center, nine endoscopists inexperienced in ESD were randomly divided into two groups (group A: ex vivo training followed by in vivo training; group B: in vivo training only), and they performed gastric ESDs. @*Results@#A total of 18 ESDs were performed. The en bloc resection rate was 88.9% (16/18), and the complete resection rate was 94.4% (17/18). The median specimen size was 2.5 cm in group A and 2.1 cm in group B (P=0.227). There was no significant difference in the procedure time between the two groups, except for the marking time (0′58″ vs. 2′58″, P=0.027). However, group A took a shorter time in dissecting the same area than group B (109 vs. 246 sec/cm2, P=0.083). Complication rates were not significantly different between both groups. @*Conclusions@#The procedure time during in vivo ESD training in pigs may be shortened by prior ex vivo training. However, the ex vivo model presented poor air inflation, unstable fixation, and excessive mucosal hardness for cutting. An advanced simulator or sufficient ex vivo training may be effective in training for the ESD procedure.

Predictive Role of Endoscopic Surveillance after Total Gastrectomy with R0 Resection for Gastric Cancer

Background@#Endoscopic surveillance after total gastrectomy (TG) for gastric cancer is routinely performed to detect tumor recurrence and postoperative adverse events.However, the reports on the clinical benefits of endoscopic surveillance are ambiguous. We investigated the clinical benefit of endoscopic surveillance after TG for gastric cancer. @*Methods@#We analyzed 848 patients who underwent TG with R0 resection for gastric cancer between 2011 and 2012 (380 early gastric cancer and 468 advanced gastric cancer) and underwent regular postoperative surveillance with endoscopy and abdominopelvic computed tomography (CT) with contrast. @*Results@#Median follow-up periods were 58 months for both endoscopy (range, 3–96) and abdominopelvic CT (range, 1–96). Tumor recurrence occurred in 167 patients (19.7%), of whom seven (4.2%) were locoregional recurrences in the peri-anastomotic area (n = 5) or regional gastric lymph nodes (n = 2). Whereas the peri-anastomotic recurrences were detected by both endoscopy and abdominopelvic CT, regional lymph node recurrences were only detected by abdominopelvic CT. Out of the 23 events of postoperative adverse events, the majority (87%) were detected by radiologic examinations; three events of benign strictures in the anastomotic site were detected only by endoscopy. @*Conclusion@#Endoscopic surveillance did not have a significant role in detecting locoregional tumor recurrence and postoperative adverse events after TG with R0 resection for gastric cancer. Routine endoscopic surveillance after TG may be considered optional and performed according to the capacities of each clinical setting.

Long-term Outcomes and Factors Affecting the Survival of Patients with Mucosal Esophageal Squamous Cell Carcinoma

Background/Aims@#Data regarding the prognosis of early esophageal cancer are lacking. This study investigated the long-term outcomes and factors affecting the survival of patients with mucosal esophageal squamous cell carcinoma (T1aESCC). @*Methods@#We analyzed the clinical and tumor-specific parameters of 263 patients who received surgical resection (SR; n=63) or endoscopic resection (ER; n=200) for T1aESCC. Underlying comorbidities were scored using the Charlson comorbidity index (CCI). Overall survival (OS) was the primary outcome, and multivariate regression analysis was performed to predict factors for OS. @*Results@#Of the study patients (age, 64.5±8.0 years), the CCI was 1.0±1.4 in the ER group and 0.6±0.9 in the SR group (p=0.107). The 5-year OS rate during follow-up (54.4±20.4 months) was 85.7% (ER group, 86.8%; SR group, 82.4%; p=0.631). The cumulative 5-year incidence of esophageal cancer recurrence was 10.5% in the ER group (vs 0% in the SR group). The overall mortality rate was 12.9% (ER group, 12.0%; SR group, 15.9%; p=0.399). The most common cause of mortality was second primary cancers in the ER group (75%) and organ dysfunction or postoperative complications in the SR group (70%). According to multivariate analysis, only CCI was significantly associated with OS (p2 and in those with a CCI ≤2 was 60.2% and 88.2%, respectively (p<0.001). The treatment method (ER vs SR) was not a significant affecting factor (p=0.238). @*Conclusions@#The long-term prognosis of patients with T1aESCC was significantly associated with underlying comorbidities.

Associations of Serum Lipid Level with Gastric Cancer Risk, Pathology, and Prognosis / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#The association of serum lipids with gastric cancer is controversial. We clarified the role of serum lipids in the development, progression, and prognosis of gastric cancer. @*Materials and Methods@#In total, 412 patients diagnosed with gastric cancer were prospectively recruited, and 2,934 control subjects who underwent screening endoscopy were enrolled from December 2013 to March 2017 to conduct a case-control study in a tertiary center. Serum lipid profiles, including total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), apolipoprotein A-I (apoA-I), and apolipoprotein B, and clinicopathologic characteristics were analyzed. @*Results@#The gastric cancer group showed significantly lower HDL-C, higher LDL-C, and lower apoA-I level than the control group. In multivariate analysis, old age (odds ratio [OR], 1.051; p < 0.001), smoking (OR, 1.337; p < 0.001), a family history of gastric cancer (OR, 2.038; p < 0.001), Helicobacter pylori seropositivity (OR, 4.240; p < 0.001), lower HDL-C (OR, 0.712; p=0.020), and higher LDL-C (p=0.002) were significant risk factors for gastric cancer. Lower HDL-C and higher LDL-C remained significant after adjustments for covariates, including age and sex. In a subgroup analysis of the gastric cancer group, lower TG levels were associated with undifferentiated histology. No serum lipids were associated with overall survival. @*Conclusion@#Lower HDL-C and higher LDL-C were associated with the risk of gastric cancer, even after adjusting for age, sex, and other factors. In the gastric cancer group, undifferentiated histology was associated with lower TG levels.

Various Novel and Emerging Technologies in Endoscopic Bariatric and Metabolic Treatments

Obesity, along with its comorbidities, has become a significant public health concern worldwide. Bariatric surgery is considered the most effective treatment modality; however, only 2% of patients with obesity undergo bariatric surgery. Endoscopic bariatric and metabolic therapies (EBMTs) are emerging alternatives to traditional bariatric surgery for patients who are not eligible for or do not prefer surgical treatment. EBMTs are generally categorized as space-occupying, gastric restrictive, aspiration, and small bowel therapies. We aimed to review various non-balloon and non-gastroplasty devices with available clinical data and discuss the possible mechanisms of action, efficacy, and safety profile of these EMBTs.