Dedicated Cold Snare vs. Traditional Snare for Polypectomy of Diminutive and Small Lesions in a Porcine Model: A Research Group for Endoscopic Instruments and Stents (REIS) Study

Background/Aims@#The aim of this in vivo animal study was to evaluate the effectiveness and safety of dedicated cold snare (DCS) compared with those of traditional snare (TS) for cold snare polypectomy (CSP). @*Methods@#A total of 36 diminutive (5 mm) and 36 small (9 mm) pseudolesions were made by electrocoagulation in the colons of mini-pigs. @*Results@#For the diminutive lesions, there were no significant differences in technical success rate, procedure time, or complete resection rate between the DCS and TS groups; the rate of uneven resection margin in the DCS group was significantly lower than that of the TS group. For small lesions, technical success rate and complete resection rate were significantly higher in the DCS group than in the TS group (100% [18/18] vs. 55.6% [10/18], p=0.003; 94.4% [17/18] vs. 40% [4/10], p=0.006). In addition, the procedure duration was significantly shorter, and the rate of uneven resection margin was significantly lower in the DCS group (28.5 sec vs. 66.0 sec, p=0.006; 11.1% [2/18] vs. 100% [10/10], p<0.001). Two cases of perforation occurred in the DCS group. Multivariate analysis revealed that DCS use was independently associated with complete resection. @*Conclusions@#DCS is superior to TS in terms of technical success, complete resection, and reducing the duration of the procedure for CSP of small polyps.

Dedicated Cold Snare vs. Traditional Snare for Polypectomy of Diminutive and Small Lesions in a Porcine Model: A Research Group for Endoscopic Instruments and Stents (REIS) Study

Background/Aims@#The aim of this in vivo animal study was to evaluate the effectiveness and safety of dedicated cold snare (DCS) compared with those of traditional snare (TS) for cold snare polypectomy (CSP). @*Methods@#A total of 36 diminutive (5 mm) and 36 small (9 mm) pseudolesions were made by electrocoagulation in the colons of mini-pigs. @*Results@#For the diminutive lesions, there were no significant differences in technical success rate, procedure time, or complete resection rate between the DCS and TS groups; the rate of uneven resection margin in the DCS group was significantly lower than that of the TS group. For small lesions, technical success rate and complete resection rate were significantly higher in the DCS group than in the TS group (100% [18/18] vs. 55.6% [10/18], p=0.003; 94.4% [17/18] vs. 40% [4/10], p=0.006). In addition, the procedure duration was significantly shorter, and the rate of uneven resection margin was significantly lower in the DCS group (28.5 sec vs. 66.0 sec, p=0.006; 11.1% [2/18] vs. 100% [10/10], p<0.001). Two cases of perforation occurred in the DCS group. Multivariate analysis revealed that DCS use was independently associated with complete resection. @*Conclusions@#DCS is superior to TS in terms of technical success, complete resection, and reducing the duration of the procedure for CSP of small polyps.

Comparison of Effectiveness between Abdominal Vibration Stimulation and Walking Exercise for Bowel Cleansing before Therapeutic Colonoscopy

Background/Aims@#Adequate bowel preparation is important for successful colonoscopy. We aimed to evaluate the clinical feasibility and effectiveness of abdominal vibration stimulation in bowel preparation before therapeutic colonoscopy. @*Methods@#A single center, prospective, randomized, investigator-blinded study was performed between January 2016 and December 2016. Patients for therapeutic colonoscopy were prospectively enrolled and assigned to either the vibrator group or walking group. Patients who refused to participate in this study as part of the experimental group consented to register in the control group instead. During the preparation period, patients assigned to the walking group walked ≥3,000 steps, whereas those assigned to the vibrator group received abdominal vibrator stimulation and restricted walking. All patients received the same colon cleansing regimen: 4-L split-dose polyethylene glycol (PEG) solution. @*Results@#Three hundred patients who received PEG solution for therapeutic colonoscopy were finally enrolled in this study (n=100 per group). Bowel cleansing with abdominal vibration stimulation showed almost similar results to that with walking exercise (Boston Bowel Preparation Scale score for the entire colon: vibrator vs walking vs control, 7.38±1.55 vs 7.39±1.55 vs 6.17±1.15, p<0.001). There were no significant differences between the vibrator group and walking group regarding instances of diarrhea after taking PEG, time to first diarrhea after taking PEG, total procedure time, and patient satisfaction. @*Conclusions@#This study indicates that, compared with conventional walking exercise, abdominal vibration stimulation achieved similar rates of bowel cleansing adequacy and colonoscopy success without compromising safety or patient satisfaction.

Impact of previous metronidazole exposure on metronidazole-based second-line quadrupletherapy for Helicobacter pylori infection

Background/Aims@#The negative effects on the eradication success of Helicobacter pylori infection after previous exposure to macrolides, including clarithromycin on clarithromycin-based first-line therapy have been demonstrated. However,whether this is true for metronidazole-based second-line quadruple therapy remains unclear. We investigated the relationship between past administration of metronidazole and the failure of metronidazole-based second-line quadruple therapy in patients with H. pylori infection. Methods: Patients over 20 years of age who were diagnosed with H. pylori infection between January 1998 and March 2016 were enrolled in this study. The relationship between the clinical parameters and the results of a C13-urea breath test after metronidazole-based second-line quadruple therapy was analyzed in patients for whom clarithromycin-based triple therapy failed to eradicate H. pylori . @*Results@#The H. pylori eradication failure rate was significantly higher in patients with a history of metronidazole use than in patients without a history of metronidazole use ( p = 0.011). Multivariable analysis showed that the odds ratio of previous metronidazole use for eradication failure was 3.468 (95% confidence interval,1.391 to 8.649; p = 0.008). In the subgroup analysis of patients with a history of metronidazole use, the duration of metronidazole use and interval between its use and eradication therapy did not significantly affect H. pylori eradication failure. @*Conclusions@#Previous exposure to metronidazole was a significant risk factor for treatment failure of metronidazole-based second-line quadruple therapy; therefore, this should be considered when establishing a treatment strategy for patients with H. pylori infection.

A Proposal for Modification of the Barcelona Clinic Liver Cancer Staging System Considering the Prognostic Implication of Performance Status

BACKGROUND/AIMS: Barcelona Clinic Liver Cancer (BCLC) C stage demonstrates considerable heterogeneity because it includes patients with either symptomatic tumors (performance status [PS], 1–2) or with an invasive tumoral pattern reflected by the presence of vascular invasion (VI) or extrahepatic spread (EHS). This study aimed to derive a more relevant staging system by modification of the BCLC system considering the prognostic implication of PS. METHODS: A total of 7,501 subjects who were registered in the Korean multicenter hepatocellular carcinoma (HCC) registry database from 2008 to 2013 were analyzed. The relative goodness-of-fit between staging systems was compared using the Akaike information criterion (AIC) and integrated area under the curve (IAUC). Three modified BCLC (m-BCLC) systems (#1, #2, and #3) were devised by reducing the role of PS. RESULTS: As a result, the BCLC C stage, which includes patients with PS 1–2 without VI/EHS, was reassigned to stage 0, A, or B according to their tumor burden in the m-BCLC #2 model. This model was identified as the most explanatory and desirable model for HCC staging by demonstrating the smallest AIC (AIC=70,088.01) and the largest IAUC (IAUC=0.722), while the original BCLC showed the largest AIC (AIC=70,697.17) and the smallest IAUC (IAUC=0.705). The m-BCLC #2 stage C was further subclassified into C1, C2, C3, and C4 according to the Child-Pugh score, PS, presence of EHS, and tumor extent. The C1 to C4 subgroups showed significantly different overall survival distribution between groups (p<0.001). CONCLUSIONS: An accurate and relevant staging system for patients with HCC was derived though modification of the BCLC system based on PS.

Improvement of Nonalcoholic Fatty Liver Disease Reduces the Risk of Type 2 Diabetes Mellitus

BACKGROUND/AIMS: Little evidence is available about the effect of change in nonalcoholic fatty liver disease (NAFLD) status on risk of diabetes mellitus (DM) development. In this study, we tried to analyze the DM risk according to change in NAFLD status over time. METHODS: Among a total of 10,141 individuals for whom routine healthcare assessment was performed, 2,726 subjects were selected according to the inclusion/exclusion criteria. NAFLD status change was determined by using serial abdominal ultrasonography and fatty liver index (FLI) during the follow-up period. RESULTS: Subjects were categorized according to change in NAFLD status as follows: 670 subjects in the persistent NAFLD group, 155 subjects in the resolved NAFLD group, 498 subjects in the incident NAFLD group, and 1,403 subjects in the no NAFLD group. Multivariate Cox regression analysis revealed that incident NAFLD (hazard ratio [HR], 1.94; 95% confidence interval [CI], 1.08 to 3.50; p=0.026) and persistent NAFLD (HR, 3.59; 95% CI, 2.05 to 6.27; p<0.001) were independent risk factors for predicting DM development, whereas the risk with resolved NAFLD was not significantly different from that with no NAFLD. FLI could reproduce the results acquired by ultrasonography. CONCLUSIONS: This study demonstrated that future DM risk could be influenced by changes in NAFLD status over time. Resolution of NAFLD could reduce the risk of future DM development, while the development of new NAFLD could increase the risk of DM development.

Efficacy and Safety of UI05MSP015CT in Functional Dyspepsia: A Randomized, Controlled Trial

BACKGROUND/AIMS: To evaluate the efficacy and safety of a controlled release, once-daily formulation of mosapride (UI05MSP015CT) in patients with functional dyspepsia (FD). METHODS: Patients with FD were randomly assigned (1:1) to receive either UI05MSP015CT (15 mg once a day, study group) or mosapride (5 mg three times a day, control group) and corresponding placebo for 4 weeks. The primary endpoint was a change in the gastrointestinal symptom score (GIS) evaluated at enrollment and after 4 weeks. Secondary endpoints were changes in the Nepean Dyspepsia Index-Korean version (NDI-K), rate of satisfactory symptom relief, and rate of adverse events. RESULTS: A total of 138 patients were enrolled (female, 73.9%; mean age, 44.0±15.4 years). After excluding patients who violated the study protocol, 59 and 58 patients from the study and control groups, respectively, were included in the per-protocol analysis. No difference was observed in drug compliance between the control and study groups (97.07%±4.52% vs 96.85%±6.05%, p=0.870). Changes in GIS scores were 9.69±6.44 and 10.01±5.92 in the study and control groups. The mean difference in GIS change between groups was 0.33 (95% confidence interval, 1.75 to 2.41), demonstrating non-inferiority of UI-05MSP015CT (p=0.755). The rate of satisfactory symptom relief was not different between the study and control groups (39.0% vs 56.9%, p=0.053). No differences in change in NDI-K score (14.3 vs 16.9, p=0.263) or rates of adverse events (12.9% vs. 4.4%, p=0.062) were observed between the study and control groups. CONCLUSIONS: Once-daily mosapride is not inferior to conventional mosapride in efficacy and is safe in patients with FD.

Can water insufflation and carbon dioxide overcome the difficulties of colonoscope insertion?

No abstract available.

Negative Histology after Endoscopic Resection: An Endoscopist's Aspect / 대한Helicobacter연구학회지

Endoscopic submucosal dissection (ESD) is accepted as the standard treatment for gastric epithelial dysplasia or early gastric cancer because it enables curative en bloc resection and complete histopathological assessment of the specimen. However, occasionally, a tumorous lesion may not be detected, and histopathological discrepancies can occur after ESD. Reportedly, the prevalence of negative histopathological results after endoscopic resection is 2.0~4.4%. Negative histopathological results after endoscopic resection are commonly attributable to complete removal of the lesion via an endoscopic forceps biopsy (EFB) at the time of the initial diagnostic endoscopic examination, an initial histopathological overestimation of the EFB specimen, and incorrect localization of the original tumor with subsequent ESD performed at a wrong site. A small tumor size and surface area are known to be significant endoscopic predictors of negative histopathological results after ESD. Therefore, clinicians should be mindful of the fact that negative histopathological findings observed after endoscopic resection warrant a comprehensive review of all pre-ESD data and an adequate follow-up to determine the cause of these findings and to detect any possibility of local recurrence.

Cytomegalovirus Gastric Ulcer Complicated with Pyloric Obstruction in a Patient with Ulcerative Colitis / 대한소화기학회지

In patients with inflammatory bowel disease (IBD), cytomegalovirus (CMV) infections could aggravate the course of IBD but it is difficult to distinguish CMV infection from IBD exacerbation endoscopically. Usually, CMV tends to localize to the colon and other organic involvements were reported very rare in the IBD patients. Herein, we report a case that CMV gastric ulcer complicated with pyloric obstruction in a patient with ulcerative colitis during ganciclovir therapy, which was resolved by surgical gastrojejunostomy with review of literature.

Non-steroidal anti-inflammatory drug-induced enteropathy

Non-steroidal anti-inflammatory drugs (NSAIDs) are well known to be associated with serious upper gastrointestinal complications, such as peptic ulcer, bleeding, perforation, and obstruction. Recently, attention has been mainly focused on the small bowel injuries caused by NSAIDs, and new endoscopic techniques such as capsule endoscopy and double balloon endoscopy can help in detecting such injuries. This article reviewed the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of small bowel injuries caused by NSAIDs. Small bowel injures by NSAIDs might occur with a similar frequency and extent as those observed in the upper gastrointestinal tract. The pathogenesis of NSAID-induced enteropathy is complex and not clearly understood. The various lesions observed in the small bowel, including petechiae, reddened folds, loss of villi, erosions, and ulcers can be detected by capsule endoscopy. A drug that could prevent or treat NSAID-induced enteropathy has not yet been developed. Therefore, further investigations should be performed to elucidate the pathogenesis of such enteropathy and develop suitable preventive and treatment strategies.

MET-Amplified Intramucosal Gastric Cancer Widely Metastatic after Complete Endoscopic Submucosal Dissection / Journal of the Korean Cancer Association, 대한암학회지

Intramucosal gastric cancer (IGC) is associated with a very low risk of lymph node metastasis; thus it is the main candidate for minimally invasive surgical procedures, such as endoscopic submucosal dissection (ESD). Herein, we document an extraordinary case of IGC, which showed a very aggressive clinical course. A 66-year-old female underwent ESD for early gastric cancer. Histologically, the tumor consisted mainly of moderately differentiated adenocarcinoma measuring 1.6 cm in diameter, and the tumor was confined to the mucosa. Despite annual esophagogastroduodenoscopic follow-up, the tumor recurred, with wide metastasis to multiple lymph nodes and bones throughout the body after three years. Fluorescence in situ hybridization study demonstrated MET gene amplification as well as low grade polysomy 7 in both original and recurrent tumors. The clinical characteristics of metastatic IGCs and the implication of MET amplification are discussed.

Nodular lymphoid hyperplasia of the stomach in a patient with multiple submucosal tumors

Nodular lymphoid hyperplasia of the stomach is a rare lymphoproliferative disorder. Here, we report a 38-year-old man who presented with multiple submucosal tumors of the stomach. Histologically, the lesions were characterized by multiple discrete submucosal nodules of lymphoid cells. The infiltrates between the lymphoid follicles were composed mainly of medium-sized lymphoid cells with abundant clear cytoplasm, as well as a few large cells with vesicular nuclei. The gastric mucosa exhibited multifocal lymphoid aggregates and some of the epithelial cells were infiltrated by small lymphocytes mimicking lymphoepithelial lesions. Histopathology was consistent with mucosa-associated lymphoid tissue lymphoma. However, the infiltrating lymphoid cells were positive for CD2, CD3, CD5, and CD7. In addition, polymerase chain reaction analysis of the immunoglobulin heavy chain and T-cell receptor gene rearrangements demonstrated polyclonality. This case was diagnosed as reactive lymphoid hyperplasia of the stomach.

Insertion of Self Expandable Metal Stent for Malignant Stomal Obstruction in a Patient with Advanced Colon Cancer

Self expandable metal stent can be used both as palliative treatment for malignant colorectal obstruction and as a bridge to surgery in patients with potentially resectable colorectal cancer. Here, we report a case of successful relief of malignant stomal obstruction using a metal stent. A 56-year-old man underwent loop ileostomy and was given palliative chemotherapy for ascending colon cancer with peritoneal carcinomatosis. Eight months after the surgery, he complained of abdominal pain and decreased fecal output. Computed tomography and endoscopy revealed malignant stomal obstruction. Due to his poor clinical condition, we inserted the stent at the stomal orifice, instead of additional surgery, and his obstructive symptoms were successfully relieved. Stent insertion is thought to be a good alternative treatment for malignant stomal obstruction, instead of surgery.

Endoscopic Treatment of 3 Cases of GIST with High Aggressive Behavior / 대한소화기내시경학회지

Gastrointestinal stromal tumors (GISTs) are the most common subepithelial tumor of the gastrointestinal tract. They originate from mesenchymal tissue. Because of difficulties in discriminating between benign and malignant GISTs, the treatment modality is selected on the base of tumor size, mitosis count, location, originating layer, and the presence of complications. Regular follow-up, open resection, or laparoscopic operation were considered main treatments for GISTs. Surgical resection is standard treatment for a huge GIST. However, the treatment method is not determined for GISTs of less than 3 cm that show a benign clinical course. Recently, endoscopic treatment was attempted because of recent endoscope developments and associated devices. We report three cases of gastric GISTs with a high risk of aggressive behavior that were successfully treated by endoscopic resection.

Efficacy of Endoscopic Ultrasonography for Prediction of Tumor Depth in Gastric Cancer

PURPOSE: As the proportion of early gastric cancer (EGC) has recently been increased, minimally invasive treatment is currently accepted as main therapy for EGC. Accurate preoperative staging is very important in determining treatment options. To know the accuracy of endoscopic ultrasonography (EUS), we compared the depth of invasion of the tumor with preoperative EUS and postoperative pathologic findings. MATERIALS AND METHODS: We retrospectively analyzed 152 patients who underwent EUS before laparoscopic gastrectomy. The preoperative EUS results were compared with the pathological findings. RESULTS: The overall proportion of coincidence for depth of invasion between EUS and pathologic results was 41.4%. Univariate analysis showed that the rate of corrected prediction of EUS for tumor depth significantly decreased for the lesions more than 3cm in diameter (P=0.033), and those with a depressed morphology (P=0.035). In multivariate analysis, the depressed type (P=0.029, OR=2.873) and upper lesion (P=0.035, OR=2.151) was the significantly independent factors influencing the inaccurate prediction of EUS for tumor depth. CONCLUSIONS: When we decide the treatment modality considering the clinical depth of invasion by EUS, the possibility of discordance with pathologic results should be considered for the lesions located in the upper third of the stomach and with a depressed morphology.

Education and Training Guidelines for the Board of the Korean Society of Gastrointestinal Endoscopy / 대한소화기내시경학회지

The Korean Society of Gastrointestinal Endoscopy (KSGE) developed regulations and a gastrointestinal endoscopy board in 1995. Although the KSGE has acquired many specialists since then, the education and training aims and guidelines were insufficient. Although endoscopic examinations are supervised by a specialist during a GI fellowship, some types of GI endoscopic examinations and treatments are difficult to obtain exposure. Fellows should acquire endoscopic skills through repeated independent endoscopic examinations after a GI fellowship. Thus, the KSGE requires training guidelines for fellowships that allow fellows to perform endoscopic examinations without a supervisor. This document is intended to provide the principles that the Committee of Education and Training of KSGE can use to develop practical guidelines for granting privileges to perform accurate GI endoscopy safely. KSGE will contribute to improving the quality of GI endoscopy by providing guidelines for fellowships and supervisors.

Clinical Characteristics of Gastrointestinal Carcinoid Tumors / 대한소화기내시경학회지

BACKGROUND/AIMS: Various factors have been reported that can predict the clinical course and outcome of patients with gastrointestinal (GI) carcinoid tumors. We analyzed the clinical characteristics of GI carcinoid tumors and the factors associated with metastasis. METHODS: We retrospectively analyzed the clinical manifestations, treatment modalities and prognosis of 83 patients with GI carcinoid tumors. RESULTS: The mean age of the patients was 48 years old. The locations of the carcinoid tumors were rectum (n=60), stomach (n=12), duodenum (n=6), appendix (n=4) and colon (n=1). The most common symptom was non-specific (n=65, 79.5%), and the mean tumor size was 11.2 mm. The main treatment modality was endoscopic resection (n=66, 79.5%). Nine patients showed metastasis, and all of their tumors were larger than 2 cm. Univariate analysis revealed that size, ulceration and invasion of the proper muscle layer were significant factors associated with metastasis. Tumor size (p=0.001) was the only independent factor on multivariate analysis. CONCLUSIONS: The diagnosis of small sized, asymptomatic GI carcinoid tumors has increased and endoscopic treatment was a useful modality. Tumor size was a predictive factor for metastasis.

A Case of Endoscopic Enucleation for Gastric Lymphoepithelioma-like Carcinoma / 대한소화기내시경학회지

Lymphoepithelioma-like carcinoma (LELC) is a rare cancer and it makes up about 1~4% of all gastric malignancies. The main histologic feature of LELC is a lymphoid stroma. LELC is rare in that its shape is similar to that of submucosal tumor (SMT). Although SMT can be divided into malignant and benign tumors, using endoscopic ultrasonography (EUS) and EUS-guided fine needle aspiration, there are still many cases that can't be discriminated, and it is especially difficult to obtain specimens due to the small size of SMT. There have been some recent trials to endoscopic remove small SMTs for the purpose of making an exact diagnosis and guiding therapy. We report here a case of gastric LELC that exhibited the features of a submucosal tumor, and this LELC was removed by endoscopic enucleation. We also briefly review the relevant medical literature.

A Hemolytic Transfusion Reaction due to Anti-Ku Antibody in a Patient with Knull Phenotype: The First Case in Korea / 대한진단검사의학회지

Knull phenotype completely lacks all Kell system antigens. Anti-Ku antibody is seen in immunized persons with Knull phenotype by transfusion or pregnancy. It can cause a fatal hemolytic transfusion reaction. A 66-yr-old male patient with liver cirrhosis visited emergency center due to acute bleeding. The patient was at hypovolemic shock status: his blood pressure was 80/50 mmHg, pulse rate was 110/min and hemoglobin level was 4.4 g/dL. Because of the presence of antibody against high incidence antigen, we could not find any compatible blood for the patient. Nevertheless, 4 units of packed RBCs had to be transfused. Moderate hemolytic transfusion reaction was developed after transfusion. At endoscopic examination, blood was spurting from gastric cardiac varix. Endoscopic histoacryl injection was tried, and bleeding was successfully controlled. After bleeding stopped, he was managed for anemia using steroid and other medical therapy instead of transfusion. His hemoglobin level was improved to 7.7 g/dL at the time of discharge. Later he has been proved to have a Knull phenotype, which is very rare, and anti-Ku antibody. This report is the first case of anti-Ku in a Knull phenotype person in Korea, who experienced a moderate hemolytic transfusion reaction.