Helicobacter pylori (H. pylori) is an important pathogen in the stomach which can cause chronic inflammation, predisposing patients to peptic ulcer disease. It is also a class 1 human carcinogen, increasing the risk of gastric carcinoma. Eradication of H. pylori has been shown to be effective in the prevention of peptic ulcer disease as well as gastric carcinoma. Singapore is an intermediate-risk area for gastric cancer, and the seroprevalence of H. pylori infection is 31 percent. Testing for H. pylori consists of non-invasive tests such as H. pylori serology, stool antigen assay, and the urea breath test, as well as invasive tests requiring oesophago-gastro-duodenoscopy (OGD) and biopsies for the rapid urease test, histology, and cultures. Stool antigen assay represents a more accurate non-invasive outpatient test for H. pylori at slightly increased cost in the primary care setting, as positive H. pylori serology does not necessarily imply active infection. Triple therapy remains an effective first-line eradication treatment in Singapore from studies of H. pylori resistance locally. Treatment failures should be retreated with quadruple therapy or other strategies such as concomitant therapy, hybrid therapy and sequential therapy.

Pancreatic necrosis with the formation of walled-off collections is a known complication of severe acute pancreatitis. Infected necrotic pancreatic collections are associated with a high mortality rate. Open necrosectomy and debridement with closed drainage has traditionally been the gold standard for treatment of infected pancreatic necrosis, but carries a high risk of perioperative complications. Direct endoscopic necrosectomy has emerged as a safe and effective modality of treatment for this condition. Careful patient selection and gentle meticulous debridement is important to optimize clinical success. Bleeding is the commonest associated complication with the procedure but most cases can be managed conservatively. Air embolism, although rare, is potentially fatal. The use of fully covered large diameter lumen apposing self-expandable metal stents has further simplified the procedure. These stents optimize drainage, and facilitate endoscopic necrosectomy because repeat insertion of the endoscope into the necrotic cavity can be easily achieved.
Debridement ; Drainage ; Embolism, Air ; Endoscopes ; Endosonography ; Hemorrhage ; Mortality ; Necrosis ; Pancreatitis ; Patient Selection ; Stents

The field of artificial intelligence is rapidly evolving, and there has been an interest in its use to predict the risk of lymph node metastasis in T1 colorectal cancer. Accurately predicting lymph node invasion may result in fewer patients undergoing unnecessary surgeries; conversely, inadequate assessments will result in suboptimal oncological outcomes. This narrative review aims to summarize the current literature on deep learning for predicting the probability of lymph node metastasis in T1 colorectal cancer, highlighting areas of potential application and barriers that may limit its generalizability and clinical utility.

BACKGROUND/AIMS: Interferon-based treatment is not appropriate for a large number of patients with chronic hepatitis C for various medical and social reasons. Newly developed directly acting antivirals (DAAs) have been used to treat chronic hepatitis C without severe adverse effects and have achieved a sustained viral response (SVR) rate of 80-90% with short treatment duration. We were interested to determine whether all patients who failed to respond to or were ineligible for interferon-based therapy could be treated with DAAs. METHODS: Medical records of patients with positive serum anti-hepatitis C virus (HCV) or HCV RNA between January 2009 and December 2013 were reviewed. Demographic, clinical, and treatment data were collected for analysis. RESULTS: A total of 876 patients were positive for both anti-HCV and HCV RNA. Of these, 244 patients were eligible for interferon, although this was associated with relapse in 39 (16%) of patients. In total, 130 patients stopped interferon therapy (67% adverse effects, 28% non-adherent, 4% malignancy, 1% alcohol abuse) and 502 patients were ineligible (66% medical contraindications, 25% non-adherent, 5% socioeconomic problems). Among 671 patients who were ineligible for or failed to respond to interferon therapy, more than 186 (27.7%) could not be treated with DAA due to financial, social, or cancer-related conditions. CONCLUSIONS: Newly developed DAAs are a promising treatment for patients with chronic hepatitis C who are ineligible for or failed to respond to interferon-based therapy. Nevertheless, not all chronic hepatitis C patients can be treated with DAAs due to various reasons.
Antiviral Agents ; Hepatitis C ; Hepatitis C, Chronic ; Humans ; Interferons* ; Medical Records ; Recurrence ; RNA

Background/Aims: Proximal colorectal cancers (CRCs) account for up to half of CRCs. Sessile serrated lesions (SSLs) are precursors to CRC. Proximal location and presence of dysplasia in SSLs predict higher risks of progression to cancer. The prevalence of dysplasia in proximal SSLs (pSSLs) and clinical characteristics of dysplastic pSSLs are not well studied. Methods: Endoscopically resected colonic polyps at our center between January 2016 and December 2017 were screened for pSSLs. Data of patients with at least one pSSL were retrieved and clinicopathological features of pSSLs were analysed. pSSLs with and without dysplasia were compared for associations. Results: Ninety pSSLs were identified, 45 of which had dysplasia giving a prevalence of 50.0%. Older age (65.9 years vs. 60.1 years, p=0.034) was associated with the presence of dysplasia. Twelve pSSLs were 10 mm or larger. After adjusting for age, pSSLs ≥10 mm had an adjusted odds ratio of 5.98 (95% confidence interval, 1.21–29.6) of having dysplasia compared with smaller pSSLs. Conclusions In our cohort of pSSLs, the prevalence of dysplasia is high at 50.0% and is associated with lesion size ≥10 mm. Endoscopic resection for all proximal serrated lesions should be en-bloc to facilitate accurate histopathological examination for dysplasia as its presence warrants shorter surveillance intervals.

Background/Aims: Proximal colorectal cancers (CRCs) account for up to half of CRCs. Sessile serrated lesions (SSLs) are precursors to CRC. Proximal location and presence of dysplasia in SSLs predict higher risks of progression to cancer. The prevalence of dysplasia in proximal SSLs (pSSLs) and clinical characteristics of dysplastic pSSLs are not well studied. Methods: Endoscopically resected colonic polyps at our center between January 2016 and December 2017 were screened for pSSLs. Data of patients with at least one pSSL were retrieved and clinicopathological features of pSSLs were analysed. pSSLs with and without dysplasia were compared for associations. Results: Ninety pSSLs were identified, 45 of which had dysplasia giving a prevalence of 50.0%. Older age (65.9 years vs. 60.1 years, p=0.034) was associated with the presence of dysplasia. Twelve pSSLs were 10 mm or larger. After adjusting for age, pSSLs ≥10 mm had an adjusted odds ratio of 5.98 (95% confidence interval, 1.21–29.6) of having dysplasia compared with smaller pSSLs. Conclusions In our cohort of pSSLs, the prevalence of dysplasia is high at 50.0% and is associated with lesion size ≥10 mm. Endoscopic resection for all proximal serrated lesions should be en-bloc to facilitate accurate histopathological examination for dysplasia as its presence warrants shorter surveillance intervals.

Colonoscopy is the reference standard procedure for the prevention and diagnosis of colorectal cancer, which is a leading cause of cancer-related deaths in Singapore. Artificial intelligence systems are automated, objective and reproducible. Artificial intelligence-assisted colonoscopy has recently been introduced into clinical practice as a clinical decision support tool. This review article provides a summary of the current published data and discusses ongoing research and current clinical applications of artificial intelligence-assisted colonoscopy.
Artificial Intelligence ; Colonic Polyps/diagnosis* ; Colonoscopy/methods* ; Colorectal Neoplasms/diagnosis* ; Diagnosis, Computer-Assisted ; Humans

Gastric cancer (GC) has a good prognosis, if detected at an early stage. The intestinal subtype of GC follows a stepwise progression to carcinoma, which is treatable with early detection and intervention using high-quality endoscopy. Premalignant lesions and gastric epithelial polyps are commonly encountered in clinical practice. Surveillance of patients with premalignant gastric lesions may aid in early diagnosis of GC, and thus improve chances of survival. An expert professional workgroup was formed to summarise the current evidence and provide recommendations on the management of patients with gastric premalignant lesions in Singapore. Twenty-five recommendations were made to address screening and surveillance, strategies for detection and management of gastric premalignant lesions, management of gastric epithelial polyps, and pathological reporting of gastric premalignant lesions.
Adenomatous Polyps ; Endoscopy ; Humans ; Precancerous Conditions/therapy* ; Singapore ; Stomach Neoplasms/therapy*

INTRODUCTION: In Singapore, non-anaesthesiologists generally administer sedation during gastrointestinal endoscopy. The drugs used for sedation in hospital endoscopy centres now include propofol in addition to benzodiazepines and opiates. The requirements for peri-procedural monitoring and discharge protocols have also evolved. There is a need to develop an evidence-based clinical guideline on the safe and effective use of sedation by non-anaesthesiologists during gastrointestinal endoscopy in the hospital setting. METHODS: The Academy of Medicine, Singapore appointed an expert workgroup comprising 18 gastroenterologists, general surgeons and anaesthesiologists to develop guidelines on the use of sedation during gastrointestinal endoscopy. The workgroup formulated clinical questions related to different aspects of endoscopic sedation, conducted a relevant literature search, adopted Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology and developed recommendations by consensus using a modified Delphi process. RESULTS: The workgroup made 16 recommendations encompassing 7 areas: (1) purpose of sedation, benefits and disadvantages of sedation during gastrointestinal endoscopy; (2) pre-procedural assessment, preparation and consent taking for sedation; (3) Efficacy and safety of drugs used in sedation; (4) the role of anaesthesiologist administered sedation during gastrointestinal endoscopy; (5) performance of sedation; (6) post-sedation care and discharge after sedation; and (7) training in sedation for gastrointestinal endoscopy for non-anaesthesiologists. CONCLUSION These recommendations serve to guide clinical practice during sedation for gastrointestinal endoscopy by non-anaesthesiologists in the hospital setting.
Conscious Sedation ; Endoscopy, Gastrointestinal ; Hospitals ; Humans ; Hypnotics and Sedatives ; Singapore

INTRODUCTION: Endoscopic submucosal dissection (ESD) provides a higher en bloc and R0 resection rate than endoscopic mucosal resection. Colorectal ESD is not widely used because of its technical difficulty and risk of complications, especially for right-sided colonic lesions. We audited the clinical outcomes of our initial experience with colorectal ESD. METHODS: We reviewed data collected from a prospective registry of patients who underwent colorectal ESD from December 2014 to March 2018. Therapeutic outcomes and procedure-related complications were analysed. RESULTS: A total of 41 patients (mean age 67.4 years, 21 male) underwent colorectal ESD. The distribution of the lesions was as follows: rectum (n = 9), sigmoid colon (n = 8), descending colon (n = 6), splenic flexure (n = 1), transverse colon (n = 5), ascending colon (n = 8) and caecum (n = 4). The mean size was 23 (range 12-50) mm. En bloc resection was achieved in 35 (85.4%) out of 41 patients, and R0 resection or clear resection margins was achieved in 33 (94.3%) of the en bloc resection patients. The lesion was upstaged in 14 (34.1%) patients after ESD. Colonic perforation occurred in 3 (7.3%) patients during ESD and was successfully treated with endoscopic clips. There was no procedure-related bleeding. No patient required surgery for management of complications. The median duration of hospitalisation was 1 (range 0-7) day. Four patients with lesions that were upstaged after ESD, from high-grade dysplasia to intramucosal carcinoma with deep submucosal invasion, were referred for colectomy. CONCLUSION Our early outcome data was comparable to that from large published series. ESD is an effective and feasible treatment for colorectal lesions.