Han-Mo Chiu

A prospective comparative study of narrow-band imaging, chromoendoscopy, and conventional colonoscopy in the diagnosis of colorectal neoplasia

Background: Discrimination between neoplastic and non-neoplastic lesions is crucial in colorectal cancer screening. Application of narrow-band imaging (NBI) in colonoscopy visualises mucosal vascular networks in neoplastic lesions and may improve diagnostic accuracy. Aim: To compare the diagnostic efficacy of NBI in differentiating neoplastic from non-neoplastic colorectal lesions with diagnostic efficacies of standard modalities, conventional colonoscopy, and chromoendoscopy. Methods: In this prospective study, 180 colorectal lesions from 133 patients were observed with conventional colonoscopy, and under low-magnification and high-magnification NBI and chromoendoscopy. Lesions were resected for histopathological analysis. Endoscopic images were stored electronically and randomly allocated to two readers for evaluation. Sensitivity, specificity and diagnostic accuracy of each endoscopic modality were assessed by reference to histopathology. Results: NBI and chromoendoscopy scored better under high magnification than under low magnification in comparison with conventional colonoscopy. The diagnostic accuracy of NBI with low or high magnification was significantly higher than that of conventional colonoscopy (low magnification: p = 0.0434 for reader 1 and p = 0.004 for reader 2; high magnification: p<0.001 for both readers) and was comparable to that of chromoendoscopy. Conclusion: Both low-magnification and high-magnification NBI were capable of distinguishing neoplastic from non-neoplastic colorectal lesions; the diagnostic accuracy of NBI was better than that of conventional colonoscopy and equivalent to that of chromoendoscopy. The role of NBI in screening colonoscopy needs further evaluation.

Asia Pacific consensus recommendations for colorectal cancer screening

Colorectal cancer (CRC) is rapidly increasing in Asia, but screening guidelines are lacking. Through reviewing the literature and regional data, and using the modified Delphi process, the Asia Pacific Working Group on Colorectal Cancer and international experts launch consensus recommendations aiming to improve the awareness of healthcare providers of the changing epidemiology and screening tests available. The incidence, anatomical distribution and mortality of CRC among Asian populations are not different compared with Western countries. There is a trend of proximal migration of colonic polyps. Flat or depressed lesions are not uncommon. Screening for CRC should be started at the age of 50 years. Male gender, smoking, obesity and family history are risk factors for colorectal neoplasia. Faecal occult blood test (FOBT, guaiac-based and immunochemical tests), flexible sigmoidoscopy and colonoscopy are recommended for CRC screening. Double-contrast barium enema and CT colonography are not preferred. In resource-limited countries, FOBT is the first choice for CRC screening. Polyps 5–9 mm in diameter should be removed endoscopically and, following a negative colonoscopy, a repeat examination should be performed in 10 years. Screening for CRC should be a national health priority in most Asian countries. Studies on barriers to CRC screening, education for the public and engagement of primary care physicians should be undertaken. There is no consensus on whether nurses should be trained to perform endoscopic procedures for screening of colorectal neoplasia.

The benefit of mass eradication of Helicobacter pylori infection: a community-based study of gastric cancer prevention

Objective To evaluate the benefit of mass eradication of Helicobacter pylori infection in reducing premalignant gastric lesions. Design Mass eradication of H pylori infection was started from 2004 for a Taiwanese population with prevalent H pylori infection, who were >30 years of age. Participants positive for the 13C-urea breath test underwent endoscopic screening and 1-week clarithromycin-based triple therapy. For subjects whose initial treatment failed, 10-day levofloxacin-based triple therapy was administered. The main outcome measures were changes in the prevalence of H pylori infection and premalignant gastric lesions, and changes in the incidence of premalignant gastric lesions and gastric cancer before (1995–2003) and after (2004–2008) chemoprevention using various comparators. Results The reduction in H pylori infection was 78.7% (95% CI 76.8% to 80.7%), and the estimated incidence of re-infection/recrudescence was 1% (95% CI 0.6% to 1.4%) per person-year. The effectiveness of reducing the incidence of gastric atrophy resulting from chemoprevention was significant at 77.2% (95% CI 72.3% to 81.2%), while the reduction in intestinal metaplasia was not significant. Compared with the 5-year period before chemoprevention and in the absence of endoscopic screening, the effectiveness in reducing gastric cancer incidence during the chemoprevention period was 25% (rate ratio 0.753, 95% CI 0.372 to 1.524). The reduction in peptic ulcer disease was 67.4% (95% CI 52.2% to 77.8%), while the incidence of oesophagitis was 6% (95% CI 5.1% to 6.9%) after treatment. Conclusions Population-based eradication of H pylori infection has led to a significant reduction in gastric atrophy at the expense of increased oesophagitis. The ultimate benefit in reducing gastric cancer incidence and its mortality should be validated by a further long-term follow-up. Trial registration number NCT00155389.

The Asia-Pacific Colorectal Screening score: a validated tool that stratifies risk for colorectal advanced neoplasia in asymptomatic Asian subjects

Objective To develop and validate a clinical risk score predictive of risk for colorectal advanced neoplasia for Asia. Methods A prospective, cross-sectional and multicentre study was carried out in tertiary hospitals in 11 Asian cities. The subjects comprise 2752 asymptomatic patients undergoing screening colonoscopy. From a development set of 860 asymptomatic subjects undergoing screening colonoscopy, multiple logistic regression was applied to identify significant risk factors for advanced colorectal neoplasia defined as invasive carcinoma or advanced adenoma. The ORs for significant risk factors were utilised to develop a risk score ranging from 0 to 7 (Asia-Pacific Colorectal Screening (APCS) score). Three tiers of risk were arbitrarily defined: 0–1 ‘average risk’ (AR); 2–3 ‘moderate risk’ (MR); and 4–7 ‘high risk’ (HR). Subjects undergoing screening colonoscopy between July 2006 and December 2007 were prospectively enrolled to form an independent validation group. Each subject had a personal APCS score calculated by summing the points attributed from the presence of risk factors in the individuals. The performance of the APCS score in predicting risk of advanced neoplasia was evaluated. Results There were 860 subjects in the derivation set and 1892 subjects in the validation set, with a baseline prevalence of advanced neoplasia of 4.5% and 3%, respectively. Applying the APCS stratification in the validation set, 559 subjects (29.5%) were in the AR tier, 966 subjects (51.1%) in the MR tier and 367 (19.4%) subjects in the HR tier. The prevalence of advanced neoplasia in the AR, MR and HR groups was 1.3, 3.2 and 5.2%, respectively. The subjects in the MR and HR tiers had 2.6-fold (95% CI 1.1 to 6.0) and 4.3-fold (95% CI 1.8 to 10.3) increased prevalence of advanced neoplasia, respectively, than those in the AR tier. Conclusions The APCS score based on age, gender, family history and smoking is useful in selecting asymptomatic Asian subjects for priority of colorectal screening.

An updated Asia Pacific Consensus Recommendations on colorectal cancer screening

Objective Since the publication of the first Asia Pacific Consensus on Colorectal Cancer (CRC) in 2008, there are substantial advancements in the science and experience of implementing CRC screening. The Asia Pacific Working Group aimed to provide an updated set of consensus recommendations. Design Members from 14 Asian regions gathered to seek consensus using other national and international guidelines, and recent relevant literature published from 2008 to 2013. A modified Delphi process was adopted to develop the statements. Results Age range for CRC screening is defined as 50–75 years. Advancing age, male, family history of CRC, smoking and obesity are confirmed risk factors for CRC and advanced neoplasia. A risk-stratified scoring system is recommended for selecting high-risk patients for colonoscopy. Quantitative faecal immunochemical test (FIT) instead of guaiac-based faecal occult blood test (gFOBT) is preferred for average-risk subjects. Ancillary methods in colonoscopy, with the exception of chromoendoscopy, have not proven to be superior to high-definition white light endoscopy in identifying adenoma. Quality of colonoscopy should be upheld and quality assurance programme should be in place to audit every aspects of CRC screening. Serrated adenoma is recognised as a risk for interval cancer. There is no consensus on the recruitment of trained endoscopy nurses for CRC screening. Conclusions Based on recent data on CRC screening, an updated list of recommendations on CRC screening is prepared. These consensus statements will further enhance the implementation of CRC screening in the Asia Pacific region.

The impact of colon preparation timing on colonoscopic detection of colorectal neoplasms¯ : A prospective endoscopist-blinded randomized trial

OBJECTIVES:Timing of colon preparation might influence the cleansing condition of the colon and therefore affect the quality and diagnostic yield of colonoscopy. This study compared two different timings of colon preparation to assess the efficacy of colon cleansing and diagnostic yield of colorectal neoplasms during colonoscopy.METHODS:One hundred twenty-one eligible subjects who had colorectal neoplasms detected at a screening colonoscopy were randomly assigned to receive colon preparation with polyethylene glycol electrolyte lavage solution (PEG-ELS) either on the day of (on the day group) or the night before (previous night group) a second colonoscopy. The condition of colon preparation and the diagnostic yield of colorectal neoplasms were recorded and compared between the two groups for the initial and second colonoscopies.RESULTS:Fifty-nine subjects received colon preparation on the night before and 60 subjects received colon preparation the day of a second colonoscopy. Colon preparation for the second colonoscopy was better in the on-the-day group than in the previous night group (P = 0.003). Colon preparation for the second colonoscopy was better for each group in comparison with the initial colonoscopy (P < 0.0001). An interobserver variability analysis using 20 randomly selected colonoscopies from the two groups revealed good correlation among four colonoscopists. More lesions were detected in group A during the second colonoscopy (P = 0.028).CONCLUSION:Colon preparation on the day of colonoscopy has a better cleansing quality and higher diagnostic yield. Subjects who had lesions detected during the initial screening colonoscopy had better colon cleansing for the second colonoscopy regardless of the timing of preparation.

Prevalence and clinical characteristics of Barrett's esophagus in a Chinese general population.

Background The prevalence of Barrett esophagus (BE) remains elusive in the general populations. Goals The purpose of this study was to identify the prevalence and clinical characteristics of BE in a Chinese general population. Study Between June 2003 and December 2006, consecutive subjects were evaluated via upper gastrointestinal endoscopy during a routine health examination. Patients were evaluated for any abnormalities, including endoscopically suspected esophageal metaplasia (ESEM) and erosive esophagitis (EE). Biopsies were attained from patients with ESEM to confirm a diagnosis of BE. The demographic data and endoscopic findings were retrospectively analyzed. Results Of the 19,812 endoscopies performed, 56 patients (0.28%) were diagnosed with ESEM and 3129 patients (15.7%) with EE. Twelve of the 56 patients diagnosed with ESEM (0.06% of the total number of patients who underwent endoscopy) were confirmed to have BE after histologic analysis of the biopsies. Patients with BE were older than patients without BE (61.6 vs. 51.7 y), and only one of the 12 patients diagnosed with BE (8.3%) reported typical gastroesophageal reflux symptoms. A majority of the BE patients were categorized as short-segment BE (91.7%) and concomitant EE was found in 4 (33.3%). Smoking, alcohol, and metabolic disorders seemed to be associated with the presence of BE and EE. Conclusions The prevalence of BE in a Chinese general population was lower than that in other reported studies, particularly in comparison with the studies originating from Western countries. Patients with advanced age and metabolic disorders are risk factors for developing BE.

Comparative analysis between psychological and endoscopic profiles in patients with gastroesophageal reflux disease: A prospective study based on screening endoscopy

Background:  Associations between psychological and endoscopic profiles are not clearly validated among the heterogeneous patients with gastroesophageal reflux disease (GERD). The purpose of the present paper was therefore to identify any associations by means of cross‐sectional study.

The effect of metabolic risk factors on the natural course of gastro-oesophageal reflux disease

Background and aims: The effect of metabolic risk factors on the natural course of gastro-oesophageal reflux disease (GORD), which remains elusive, was quantified. Methods: The population included 3669 subjects undergoing repeated upper endoscopy. Data were analysed using a three-state Markov model to estimate transition rates (according to the Los Angeles classification) regarding the natural course of the disease. Individual risk score together with the kinetic curve was derived by identifying significant factors responsible for the net force between progression and regression. Results: During three consecutive study periods, 12.2, 14.9 and 17.9% of subjects, respectively, progressed from non-erosive to erosive disease, whereas 42.5, 37.3 and 34.6%, respectively, regressed to the non-erosive stage. The annual transition rate from non-erosive to class A–B disease was 0.151 per person year (95% CI 0.136 to 0.165) and from class A–B to C–D was 0.079 per person year (95% CI 0.063 to 0.094). The regression rate from class A–B to non-erosive disease was 0.481 per person year (95% CI 0.425 to 0.536). Class C–D, however, appeared to be an absorbing state when not properly treated. Being male (relative risk (RR) 4.31; 95% CI 3.22 to 5.75), smoking (RR 1.20; 95% CI 1.03 to 1.39) or having metabolic syndrome (RR 1.75; 95% CI 1.29 to 2.38) independently increased the likelihood of progressing from a non-erosive to an erosive stage of disease and/or lowered the likelihood of disease regression. The short-term use of acid suppressants (RR 0.54; 95% CI 0.39 to 0.75) raised the likelihood of regression from erosive to non-erosive disease. Conclusions: Intraoesophageal damage is a dynamic and migratory process in which the metabolic syndrome is associated with accelerated progression to or attenuated regression from erosive states. These findings have important implications for the design of effective prevention and screening strategies.

Transnasal endoscopy with narrow-band imaging and Lugol staining to screen patients with head and neck cancer whose condition limits oral intubation with standard endoscope (with video)

BACKGROUND Early detection of esophageal cancer in patients with head and neck cancers may alter treatment planning and improve survival. However, standard endoscopic screening is not feasible for some patients with tumor-related airway compromise or postirradiation trismus. OBJECTIVE To evaluate a novel, sequential approach by integrating ultrathin endoscopy with narrow-band imaging and Lugol chromoendoscopy. DESIGN Cross-sectional study. SETTING Single center in Taiwan. PATIENTS Forty-four consecutive patients with transoral difficulty screened for synchronous or metachronous esophageal cancer. MAIN OUTCOME MEASUREMENTS Sensitivity, specificity, and accuracy in the detection of mucosal high-grade neoplasia or invasive cancer. RESULTS Fifty-four endoscopic interpretations were obtained, and 11 mucosal high-grade neoplasia and 7 invasive cancers were confirmed by histology. The mean examination time was 19.4 minutes (range 7.9-35.2 minutes), and all patients tolerated the procedure well. Sensitivity, specificity, and accuracy (with 95% CI) were 55.6% (95% CI, 33.5%-75.6%), 97.2% (95% CI, 85.8%-99.3%), and 83.3% (95% CI, 71.2%-90.9%), respectively, for standard endoscopy; 88.9% (95% CI, 66.9%-96.6%), 97.2% (95% CI, 85.8%-99.3%), and 94.4% (95% CI, 84.9%-97.9%), respectively, with the adjunct of narrow-band imaging; and 88.9% (95% CI, 66.9%-96.6%), 72.2% (95% CI, 55.9%-84.1%), and 77.8% (95% CI, 64.9%-86.8%), respectively, with the adjunct of Lugol chromoendoscopy. When we integrated all interpretations on the basis of the sequential approach, the estimated probability of false-negative findings was 1.2% (95% CI, 0.1%-4.6%). LIMITATIONS Inherent shortcomings of ultrathin endoscopy, such as its resolution, light source, and lack of magnification. CONCLUSIONS The use of ultrathin endoscopy in a sequential approach for multimodal detection is feasible in patients with transoral difficulty and substantially increases the detection rate of synchronous or metachronous neoplasms.