Background and study aims  Endoscopic mucosal resection (EMR) is a standard method for removing sessile colorectal polyps ≥ 10 mm. Recently, underwater EMR (UEMR) has been introduced as a potential alternative. However, the effectiveness and safety of UEMR compared with conventional EMR is un clear. Patients and methods  In this 1:1 propensity score (PS) matched retrospective cohort study, we compared the en bloc resection rates, procedure time, intraprocedural and delayed bleeding rates, and incidence of muscle layer injury. We also performed subgroup analyses by sizes of polyps (< 20 mm and ≥ 20 mm). Results  Among 350 polyps in 315 patients from August 2012 to November 2017, we identified 121 PS-matched pairs. Mean polyp size was 16.8 mm. With similar en bloc resection rates (EMR: 82.6 % vs. UEMR: 87.6 %, rate difference: 5.0, 95 % confidence interval [95 % CI]: – 4 to 13.9 %), UEMR demonstrated a shorter resection time (10.8 min vs. 8.6 min, difference: – 2.2 min, 95 % CI: – 4.1 to – 0.3 min) and a lower intraprocedural bleeding rate (15.7 % vs. 5.8 %, rate difference: – 9.9 %, 95 % CI: – 17.6 to – 2.2 %). Incidence of delayed bleeding and muscle layer injury were low in both groups. For polyps < 20 mm, effectiveness and safety outcomes were similar in both groups. For polyps ≥ 20 mm (42 PS-matched pairs), the UEMR group has a comparable en bloc resection rate with shorter procedure time and superior safety outcomes Conclusions  UEMR achieved an en bloc resection rate comparable to conventional EMR with less intraprocedural bleeding and a shorter procedure time.

Background and Aim: The mortality rate of gastric cancer (GC) is close to the incidence rate worldwide. However, in Korea and Japan, the mortality rate of GC is less than half of the incidence rate. We hypothesized that good-quality routine esophagogastroduodenoscopy (EGD) contributes to a high detection rate for early GC (EGC) and improves mortality in these countries. Methods:To clarify the differences in routine EGD, a questionnaire survey was conducted in 98 Japanese and 53 international institutions.Results: Prevalence of screening examination among routine EGD was higher in Japanese than in international institutions. Japanese endoscopists noted that endoscopic mucosal atrophy was the most significant risk factor for GC, whereas international endoscopists paid more attention to clinical information such as age, symptoms and family history. Antispasmodics, mucolytics and defoaming agents were used more frequently in Japanese institutions. The examination time was similar (mostly 5-10 min) between Japanese and international institutions. Japanese endoscopists took more pictures (>20 in almost all institutions) than international endoscopists (≤20 in two-thirds of institutions). In Japanese institutions, biopsy specimens were more frequently taken from areas of mucosal discoloration, unevenness or spontaneous bleeding rather than from obvious endoscopic lesions such as ulceration or polyps. In most Japanese institutions, one or two biopsy specimens were taken per lesion, compared with ≥three in international institutions.Conclusion: There were some discrepancies between Japanese and international institutions for routine EGD. Thus, standardization is required for adequate risk assessment, proper techniques, and knowledge of endoscopic diagnosis of EGC.

Endoscopic diagnosis of gastrointestinal tumors consists of the following processes: (i) detection; (ii) differential diagnosis; and (iii) quantitative diagnosis (size and depth) of a lesion. Although detection is the first step to make a diagnosis of the tumor, the lesion can be overlooked if an endoscopist has no knowledge of what an earlystage 'superficial lesion' looks like. In recent years, image-enhanced endoscopy has become common, but white-light endoscopy (WLI) is still the first step for detection and characterization of lesions in general clinical practice. Settings and practice of routine esophagogastroduodenoscopy (EGD) such as use of antispasmodics, number of endoscopic images taken, and observational procedure are customarily decided in each facility in each country and are not well standardized. Therefore, in the present article, we attempted to outline currently available evidence and actual Japanese practice on gastric cancer screening using WLI, and provide tips for detecting EGC during routine EGD which could become the basis of future research.Key words: gastric atrophy, gastric cancer, Helicobacter pylori, Kimura-Takemoto classification, screening gastroscopy MEDICAL INTERVIEW PRIOR TO ESOPHAGOGASTRODUODENOSCOPY M EDICALINTERVIEW BEFORE esophagogastroduodenoscopy (EGD) is important in terms of the following two points. One is to confirm indication of the EGD and the other is to assess risk of examinees. Whether indication for EGD is to screen for early gastric cancer (EGC) or to make a diagnosis of a patient's symptoms or abnormal findings in other diagnostic examinations should be distinguished. In the screening endoscopy, the entire gastric mucosa is thoroughly observed to detect any suspicious findings for neoplasia, whereas only the presence of apparent lesions that may cause symptoms or abnormal image findings are investigated. Although endoscopy is usually intended to make a diagnosis of symptoms or abnormal findings in other diagnostic images, EGC are often found in patients with neither obvious symptoms nor abnormal findings in other diagnostic tests.1 Therefore, in high-risk patients, it is important to screen for EGC unrelated to symptoms or abnormal find-ings of other diagnostic tests during EGD. The examinee should be asked about status and history of eradication therapy of Helicobacter pylori (H. pylori), 2-4 family history of gastric cancer, smoking and drinking habits. [5][6][7][8] Another reason for the medical interview is to reduce 10 and an anti-foaming agent 11 reduces time and effort for washing out mucus or bubbles to improve quality of observation. A mixture of 4 mL anti-foaming agent (dimethicone, Gascon ® 20 mg/mL; Horii Pharmaceutical Industry, Osaka Japan), 20 000 U mucolytic agent (Pronase MS ® ; Kaken Pharmaceutical, Tokyo, Japan), and 1 g sodium bicarbonate dissolved in 50 mL water is given 10 min before the examination. 12Usefulness of a topical pharyngeal anesthetic is controversial although it is commonly used before gastroscopy. 13,14 UK data show that to...

A well-designed training program can improve the diagnostic accuracy in evaluating cancer invasion depth, with substantial agreement.