Effect of Real-Time Computer-Aided Polyp Detection System (ENDO-AID) on Adenoma Detection in Endoscopists-in-Training: A Randomized Trial.

BACKGROUND: The effect of computer-aided polyp detection (CADe) on adenoma detection rate (ADR) among endoscopists-in-training remains unknown. METHODS: We performed a single-blind, parallel-group, randomized controlled trial in Hong Kong between April 2021 and July 2022 (NCT04838951). Eligible subjects undergoing screening/surveillance/diagnostic colonoscopies were randomized 1:1 to receive colonoscopies with CADe (ENDO-AID[OIP-1]) or not (control) during withdrawal. Procedures were performed by endoscopists-in-training with <500 procedures and <3 years' experience. Randomization was stratified by patient age, sex, and endoscopist experience (beginner vs intermediate level, <200 vs 200-500 procedures). Image enhancement and distal attachment devices were disallowed. Subjects with incomplete colonoscopies or inadequate bowel preparation were excluded. Treatment allocation was blinded to outcome assessors. The primary outcome was ADR. Secondary outcomes were ADR for different adenoma sizes and locations, mean number of adenomas, and non-neoplastic resection rate. RESULTS: A total of 386 and 380 subjects were randomized to CADe and control groups, respectively. The overall ADR was significantly higher in the CADe group than in the control group (57.5% vs 44.5%; adjusted relative risk, 1.41; 95% CI, 1.17-1.72; P < .001). The ADRs for <5 mm (40.4% vs 25.0%) and 5- to 10-mm adenomas (36.8% vs 29.2%) were higher in the CADe group. The ADRs were higher in the CADe group in both the right colon (42.0% vs 30.8%) and left colon (34.5% vs 27.6%), but there was no significant difference in advanced ADR. The ADRs were higher in the CADe group among beginner (60.0% vs 41.9%) and intermediate-level (56.5% vs 45.5%) endoscopists. Mean number of adenomas (1.48 vs 0.86) and non-neoplastic resection rate (52.1% vs 35.0%) were higher in the CADe group. CONCLUSIONS: Among endoscopists-in-training, the use of CADe during colonoscopies was associated with increased overall ADR. (ClinicalTrials.gov, Number: NCT04838951).

Artificial Intelligence-Assisted Colonoscopy for Colorectal Cancer Screening: A Multicenter Randomized Controlled Trial.

BACKGROUND AND AIMS: Artificial intelligence (AI)-assisted colonoscopy improves polyp detection and characterization in colonoscopy. However, data from large-scale multicenter randomized controlled trials (RCT) in an asymptomatic population are lacking. METHODS: This multicenter RCT aimed to compare AI-assisted colonoscopy with conventional colonoscopy for adenoma detection in an asymptomatic population. Asymptomatic subjects 45-75 years of age undergoing colorectal cancer screening by direct colonoscopy or fecal immunochemical test were recruited in 6 referral centers in Hong Kong, Jilin, Inner Mongolia, Xiamen, and Beijing. In the AI-assisted colonoscopy, an AI polyp detection system (Eagle-Eye) with real-time notification on the same monitor of the endoscopy system was used. The primary outcome was overall adenoma detection rate (ADR). Secondary outcomes were mean number of adenomas per colonoscopy, ADR according to endoscopist's experience, and colonoscopy withdrawal time. This study received Institutional Review Board approval (CRE-2019.393). RESULTS: From November 2019 to August 2021, 3059 subjects were randomized to AI-assisted colonoscopy (n = 1519) and conventional colonoscopy (n = 1540). Baseline characteristics and bowel preparation quality between the 2 groups were similar. The overall ADR (39.9% vs 32.4%; P < .001), advanced ADR (6.6% vs 4.9%; P = .041), ADR of expert (42.3% vs 32.8%; P < .001) and nonexpert endoscopists (37.5% vs 32.1%; P = .023), and adenomas per colonoscopy (0.59 ± 0.97 vs 0.45 ± 0.81; P < .001) were all significantly higher in the AI-assisted colonoscopy. The median withdrawal time (8.3 minutes vs 7.8 minutes; P = .004) was slightly longer in the AI-assisted colonoscopy group. CONCLUSIONS: In this multicenter RCT in asymptomatic patients, AI-assisted colonoscopy improved overall ADR, advanced ADR, and ADR of both expert and nonexpert attending endoscopists. (ClinicalTrials.gov, Number: NCT04422548).

Impact of COVID-19 infection and vaccination in pancreatobiliary IgG4-related disease patients: An international multicenter study.

BACKGROUND AND AIM: Dedicated studies evaluating the impact of COVID-19 on outcomes of pancreatobiliary IgG4 related disease (IgG4-RD) patients are scarce. Whether COVID-19 infection or vaccination would trigger IgG4-RD exacerbation remains unknown. METHODS: Pancreatobiliary IgG4-RD patients ≥ 18 years old with active follow-up since January 2020 from nine referral centers in Asia, Europe, and North America were included in this multicenter retrospective study. Outcome measures include incidence and severity of COVID-19 infection, IgG4-RD disease activity and treatment status, interruption of indicated IgG4-RD treatment. Prospective data on COVID-19 vaccination status and new COVID-19 infection during the Omicron outbreak were also retrieved in the Hong Kong cohort. RESULTS: Of the 124 pancreatobiliary IgG4-RD patients, 25.0% had active IgG4-RD, 71.0% were on immunosuppressive therapies and 80.6% had ≥ 1 risk factor for severe COVID. In 2020 (pre-vaccination period), two patients (1.6%) had COVID-19 infection (one requiring ICU admission), and 7.2% of patients had interruptions in indicated immunosuppressive treatment for IgG4-RD. Despite a high vaccination rate (85.0%), COVID-19 infection rate has increased to 20.0% during Omicron outbreak in the Hong Kong cohort. A trend towards higher COVID-19 infection rate was noted in the non-fully vaccinated/unvaccinated group (17.6% vs 33.3%, P = 0.376). No IgG4-RD exacerbation following COVID-19 vaccination or infection was observed. CONCLUSION: While a low COVID-19 infection rate with no mortality was observed in pancreatobiliary IgG4-RD patients in the pre-vaccination period of COVID-19, infection rate has increased during the Omicron outbreak despite a high vaccination rate. No IgG4-RD exacerbation after COVID-19 infection or vaccination was observed.

Two vs One Forward View Examination of Right Colon on Adenoma Detection: An International Multicenter Randomized Trial.

BACKGROUND & AIMS: Second forward view (SFV) examination of the right colon (RC) in colonoscopy was suggested to improve the adenoma detection rate (ADR), but multicenter data to inform its routine use remain limited. We performed an international multicenter randomized trial comparing SFV vs a standard single forward view examination of the RC on adenoma detection. METHODS: Asymptomatic individuals undergoing screening or surveillance colonoscopies from 6 Asia Pacific regions were invited for study. A forward view examination of the RC was first performed in all patients, followed by randomization at the hepatic flexure to either SFV examination of the RC and standard withdrawal examination from the hepatic flexure to rectum, or a standard withdrawal colonoscopy (SWC) examination from the hepatic flexure to rectum. The primary outcome was RC ADR. RESULTS: Between 2016 and 2019, there were 1011 patients randomized (SFV group, 502 patients; SWC group, 509 patients). Forty-five endoscopists performed the colonoscopies. The RC ADR was significantly higher in the SFV group than in the SWC group (27.1% vs 21.6%; P = .042). The whole-colon ADR was high in both groups (49.0% vs 45.0%; P =.201). The SFV examination identified 58 additional adenomas in 49 patients (9.8%), leading to a change in surveillance recommendations in 15 patients (3.0%). The median overall withdrawal time was 1.5 minutes longer in the SFV group (12.0 vs 10.5 min; P < .001). Older age, male sex, ever smoking, and longer RC withdrawal time were independent predictors of right-sided adenoma detection. CONCLUSIONS: In this multicenter trial, SFV examination significantly increased the RC ADR in screening and surveillance colonoscopies. Routine RC SFV examination should be considered. ClinicalTrials.gov ID: NCT03121495.

Randomized Controlled Trials of Artificial Intelligence in Clinical Practice: Systematic Review.

BACKGROUND: The number of artificial intelligence (AI) studies in medicine has exponentially increased recently. However, there is no clear quantification of the clinical benefits of implementing AI-assisted tools in patient care. OBJECTIVE: This study aims to systematically review all published randomized controlled trials (RCTs) of AI-assisted tools to characterize their performance in clinical practice. METHODS: CINAHL, Cochrane Central, Embase, MEDLINE, and PubMed were searched to identify relevant RCTs published up to July 2021 and comparing the performance of AI-assisted tools with conventional clinical management without AI assistance. We evaluated the primary end points of each study to determine their clinical relevance. This systematic review was conducted following the updated PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 guidelines. RESULTS: Among the 11,839 articles retrieved, only 39 (0.33%) RCTs were included. These RCTs were conducted in an approximately equal distribution from North America, Europe, and Asia. AI-assisted tools were implemented in 13 different clinical specialties. Most RCTs were published in the field of gastroenterology, with 15 studies on AI-assisted endoscopy. Most RCTs studied biosignal-based AI-assisted tools, and a minority of RCTs studied AI-assisted tools drawn from clinical data. In 77% (30/39) of the RCTs, AI-assisted interventions outperformed usual clinical care, and clinically relevant outcomes improved with AI-assisted intervention in 70% (21/30) of the studies. Small sample size and single-center design limited the generalizability of these studies. CONCLUSIONS: There is growing evidence supporting the implementation of AI-assisted tools in daily clinical practice; however, the number of available RCTs is limited and heterogeneous. More RCTs of AI-assisted tools integrated into clinical practice are needed to advance the role of AI in medicine. TRIAL REGISTRATION: PROSPERO CRD42021286539; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=286539.

Mobile messenger-initiated reminders improve longitudinal adherence in a community-based, opportunistic colorectal cancer screening program: A single-blind, crossover randomized controlled study.

BACKGROUND: The fecal immunochemical test (FIT) is a cost-effective colorectal cancer (CRC) screening tool. However, longitudinal adherence, a factor that is critical to the success to any FIT-based screening program, often is poor. The authors hypothesized that reminders sent via mobile messengers, such as WhatsApp, improve such adherence. METHODS: In the current single-blind, randomized study, subjects from an opportunistic FIT screening program who had a negative FIT result the year prior were randomly allocated (1:1) to receive either a 1-off reminder via the WhatsApp messenger (WR) 1 month prior to the due appointments or no reminder (NR). All subjects were blinded to study participation and group allocation. At 24 months after randomization, a crossover of intervention was performed among those individuals who remained in the FIT program. The primary outcome was FIT adherence, defined as the pick-up and on-time return of the FIT. The secondary outcome was FIT adherence after the crossover. RESULTS: A total of 500 subjects were randomized to receive WR (250 subjects) or NR (250 subjects). Three individuals were excluded from analysis (1 died and 2 underwent colonoscopy). Both the FIT pick-up rate (80.3% vs 59.3%; P < .001) and return rate (79.9% vs 57.3%; P < .001) were significantly higher in the WR group compared with the NR group. After crossover of intervention (452 subjects), the WR group again was found to have a higher FIT pick-up rate (79.1% vs 52.9%; P < .001) and return rate (78.2% vs 52.4%; P < .001). CONCLUSIONS: Text reminders sent via mobile messenger appear to improve the longitudinal adherence to FIT-based opportunistic CRC screening programs. The routine use of this technology in CRC screening should be considered.

Prevalence and risk factors for sessile serrated lesions in an average risk colorectal cancer screening population.

BACKGROUND AND AIM: The reported prevalence and risk factors for sessile serrated lesions (SSLs) show significant variation. We aimed to specifically study the prevalence and potential risk factors of SSLs in an average risk colorectal cancer (CRC) screening population of Chinese subjects. METHODS: This is a case-control study of prospectively collected data from a territory-wide colorectal screening program in Hong Kong. Information on risk factors was obtained from questionnaires completed prior to screening colonoscopy. We compared subjects with SSLs against controls without these lesions to identify potential risk factors using multivariable logistic regression. RESULTS: Of 12 039 asymptomatic screening subjects, 6011 subjects received a screening colonoscopy with 2214 subjects (36.8%) having conventional adenomas, 486 subjects (8.1%) having hyperplastic polyps, and 85 subjects (1.4%) having SSLs only. Of these subjects, three had synchronous advanced adenomas and were excluded from the analysis. More than 60% of these lesions were in the proximal colon. We compared these 82 subjects with SSLs only and 3226 controls without any polyps. After multivariable logistic regression, age ≥ 66 years, smoking, and diabetes mellitus (DM) were significant independent risk factors for SSLs. CONCLUSION: In this study, we report the prevalence of SSLs to be 1.4%. Age ≥ 66 years, smoking, and DM were independent risk factors for these lesions. Our findings provide relevant new data that should be taken into consideration when designing region-specific surveillance programs for SSLs with the ultimate goal of reducing the risk of CRC.

Short Message Service reminders reduce outpatient colonoscopy nonattendance rate: A randomized controlled study.

BACKGROUND AND AIM: Nonattendance of outpatient colonoscopy leads to inefficient use of health-care resources. We aimed to study the effectiveness of using Short Message Service (SMS) reminder prior in patients scheduled for outpatient colonoscopy on their nonattendance rate. METHODS: Patients who scheduled for an outpatient colonoscopy and had access of SMS were recruited from three clinics in Hong Kong. Patients were randomized to SMS group and standard care (SC) group. All patients were given a written appointment slip on the booking date. In addition, patients in the SMS group received an SMS reminder 7-10 days before their colonoscopy appointment. Patients' demographics, attendance, colonoscopy completion, and bowel preparation quality were recorded. Logistic regression was performed to identify predictors of nonattendance. RESULTS: From November 2013 to October 2019, a total of 2225 eligible patients were recruited. A total of 1079 patients were allocated to the SMS group and 1146 to the SC group. The nonattendance rate of patients in the SMS group was significantly lower than that in the SC group (8.9% vs 11.9%, P = 0.022). There were no significant differences in their baseline characteristics and colonoscopy completion rate and bowel preparation quality. A trend towards a higher rate of adequate bowel preparation was observed in the SMS group when compared with the SC group (69.9% vs 65.8%, P = 0.053). Independent predictors for nonattendance included younger age, underprivilege, and existing diabetes. CONCLUSIONS: An SMS reminder for outpatient colonoscopy is effective in reducing the nonattendance rate and may potentially improve the bowel preparation quality.

Endoscopic ultrasound-guided cyanoacrylate injection to prevent rebleeding in hepatocellular carcinoma patients with variceal hemorrhage.

BACKGROUND AND AIM: Secondary prophylaxis (SP) of variceal rebleeding was reported to improve outcomes of hepatocellular carcinoma (HCC) patients, but the optimal endoscopic approach is not well defined. We compared outcomes in HCC patients who underwent SP by endoscopic ultrasound-guided cyanoacrylate obturation (EUS-CYA) versus no SP. METHODS: Between 2014 and 2018, 30 consecutive patients with inoperable HCC and recent endoscopically controlled variceal bleeding were prospectively recruited. Twenty-seven patients with persistent varices ≥ 3 mm on endoscopic ultrasound underwent EUS-CYA for SP. Thirty-three HCC patients treated by esophagogastroduodenoscopy-guided CYA obturation (EGD-CYA) alone for acute variceal bleeding between 2009 and 2013 were identified from a prospective gastrointestinal bleed registry as standard of care controls for comparison. Outcome measures were death-adjusted cumulative incidence of rebleeding, bleeding-free survival, technical success, and procedure-related adverse events of EUS-CYA. RESULTS: The majority of patients in both groups had advanced HCC, portal vein thrombosis, and Child-Pugh B cirrhosis. EUS-CYA was successful in all 27 patients with no radiographic evidence of cyanoacrylate-lipiodol embolization. Significantly lower 30- and 90-day death-adjusted cumulative incidence of rebleeding (14.8% vs 42.4%, P = 0.023 and 18.5% vs 60.6%, P = 0.002, respectively) and significantly higher variceal bleeding-free survival at 3 and 6 months (51.9% vs 21.2%, P = 0.009, 40.7% vs 15.2%, P = 0.010, respectively) were observed in the EUS-CYA group when compared with standard of care group. CONCLUSIONS: Secondary prophylaxis by EUS-CYA reduced rebleeding rate and improved variceal bleeding-free survival in patients with inoperable HCC and variceal bleeding when compared with no SP. Randomized studies are needed to confirm the benefits of EUS-CYA for this difficult-to-treat population.

A modified colorectal screening score for prediction of advanced neoplasia: A prospective study of 5744 subjects.

BACKGROUND AND AIM: We validated a modified risk algorithm based on the Asia-Pacific Colorectal Screening (APCS) score that included body mass index (BMI) for prediction of advanced neoplasia. METHODS: Among 5744 Chinese asymptomatic screening participants undergoing a colonoscopy in Hong Kong from 2008 to 2012, a random sample of 3829 participants acted as the derivation cohort. The odds ratios for significant risk factors identified by binary logistic regression analysis were used to build a scoring system ranging from 0 to 6, divided into "average risk" (AR): 0; "moderate risk" (MR): 1-2; and "high risk" (HR): 3-6. The other 1915 subjects formed a validation cohort, and the performance of the score was assessed. RESULTS: The prevalence of advanced neoplasia in the derivation and validation cohorts was 5.4% and 6.0%, respectively (P = 0.395). Old age, male gender, family history of colorectal cancer, smoking, and BMI were significant predictors in multivariate regression analysis. A BMI cut-off at > 23 kg/m2 had better predictive capability and lower number needed to screen than that of > 25 kg/m2 . Utilizing the score developed, 8.4%, 57.4%, and 34.2% in the validation cohort were categorized as AR, MR, and HR, respectively. The corresponding prevalence of advanced neoplasia was 3.8%, 4.3%, and 9.3%. Subjects in the HR group had 2.48-fold increased prevalence of advanced neoplasia than the AR group. The c-statistics of the modified score had better discriminatory capability than that using predictors of APCS alone (c-statistics = 0.65 vs 0.60). CONCLUSIONS: Incorporating BMI into the predictors of APCS score was found to improve risk prediction of advanced neoplasia and reduce colonoscopy resources.

Quantitation of faecal Fusobacterium improves faecal immunochemical test in detecting advanced colorectal neoplasia.

OBJECTIVE: There is a need for an improved biomarker for colorectal cancer (CRC) and advanced adenoma. We evaluated faecal microbial markers for clinical use in detecting CRC and advanced adenoma. DESIGN: We measured relative abundance of Fusobacterium nucleatum (Fn), Peptostreptococcus anaerobius (Pa) and Parvimonas micra (Pm) by quantitative PCR in 309 subjects, including 104 patients with CRC, 103 patients with advanced adenoma and 102 controls. We evaluated the diagnostic performance of these biomarkers with respect to faecal immunochemical test (FIT), and validated the results in an independent cohort of 181 subjects. RESULTS: The abundance was higher for all three individual markers in patients with CRC than controls (p<0.001), and for marker Fn in patients with advanced adenoma than controls (p=0.022). The marker Fn, when combined with FIT, showed superior sensitivity (92.3% vs 73.1%, p<0.001) and area under the receiver-operating characteristic curve (AUC) (0.95 vs 0.86, p<0.001) than stand-alone FIT in detecting CRC in the same patient cohort. This combined test also increased the sensitivity (38.6% vs 15.5%, p<0.001) and AUC (0.65 vs 0.57, p=0.007) for detecting advanced adenoma. The performance gain for both CRC and advanced adenoma was confirmed in the validation cohort (p=0.0014 and p=0.031, respectively). CONCLUSIONS: This study identified marker Fn as a valuable marker to improve diagnostic performance of FIT, providing a complementary role to detect lesions missed by FIT alone. This simple approach may improve the clinical utility of the current FIT, and takes one step further towards a non-invasive, potentially more accurate and affordable diagnosis of advanced colorectal neoplasia.

Screening strategies for colorectal cancer among patients with nonalcoholic fatty liver disease and family history.

Patients with nonalcoholic fatty liver disease (NAFLD) and family history of colorectal cancer (CRC) are at higher risks but how they should be screened remains uncertain. Hence, we evaluated the cost-effectiveness of CRC screening among patients with NAFLD and family history by different strategies. A hypothetical population of 100,000 subjects aged 40-75 years receive: (i) yearly fecal immunochemical test (FIT) at 50 years; (ii) flexible sigmoidoscopy (FS) every 5 years at 50 years; (iii) colonoscopy 10 yearly at 50 years; (iv) colonoscopy 10 yearly at 50 years among those with family history/NAFLD and yearly FIT at 50 years among those without; (v) colonoscopy 10 yearly at 40 years among those with family history/NAFLD and yearly FIT at 50 years among those without and (vi) colonoscopy 10 yearly at 40 years among those with family history/NAFLD and colonoscopy 10 yearly at 50 years among those without. The incremental cost-effectiveness ratio (ICER) was studied by Markov modeling. It was found that colonoscopy, FS and FIT reduced incidence of CRC by 49.5, 26.3 and 23.6%, respectively. Using strategies 4, 5 and 6, the corresponding reduction in CRC incidence was 29.9, 30.9 and 69.3% for family history, and 33.2, 34.7 and 69.8% for NAFLD. Compared with no screening, strategies 4 (US$1,018/life-year saved) and 5 (US$7,485) for family history offered the lowest ICER, whilst strategy 4 (US$5,877) for NAFLD was the most cost-effective. These findings were robust when assessed with a wide range of deterministic sensitivity analyses around the base case. These indicated that screening patients with family history or NAFLD by colonoscopy at 50 years was economically favorable.

Association of distal hyperplastic polyps and proximal neoplastic lesions: a prospective study of 5613 subjects.

BACKGROUND AND AIMS: Current evidence of whether distal hyperplastic polyps (HPs) are markers of proximal neoplasia (PN) is mixed. We evaluated the association between distal neoplasia and synchronous PN in asymptomatic subjects. METHODS: We recruited 5819 Chinese asymptomatic screening participants 50 to 70 years of age who underwent colonoscopy in Hong Kong from 2008 to 2014, of whom 206 subjects with distal advanced neoplasia or cancer were excluded. The association between distal pathology (tubular adenomas [TAs], HPs, no polyps) and proximal pathology (PN, proximal advanced neoplasia [PAN]) was assessed by multivariate regression models, overall and stratified by the Asia Pacific Colorectal Screening scoring system (scores of 4-7, high risk; scores of 0-3, lower risk). RESULTS: The prevalence of PN in the no distal polyps group, distal HPs group, and distal TAs group was 14.8%, 19.3%, and 29.4%, respectively. The corresponding prevalence of PAN was 1.8%, 3.2%, and 3.5%. Participants with distal HPs did not have significantly higher odds of PN (adjusted odds ratio [AOR] 1.24; 95% confidence interval [CI], 0.97-1.59; P = .089), and their association with PAN was marginally significant (AOR 1.77; 95% CI, 1.00-3.13; P = .052), except in lower risk subjects for whom the odds of PAN were marginally higher in the distal HPs group than the no distal polyps group (AOR 1.97; 95% CI, 1.01-3.85; P = .048). Overall, the distal polyps group had significantly lower odds of PN than the distal TAs group (AOR 0.55; 95% CI, 0.40-0.76; P < .001). The increased risk of PN and PAN among those with distal HPs was modest. CONCLUSIONS: A direct association between distal HPs and PN is lacking, and this implies a need for a multivariate assessment of the risk of PAN. Recommending colonoscopy for every patient with distal HPs detected by screening sigmoidoscopy is not supported by this study.

Prediction of proximal advanced neoplasia: a comparison of four existing sigmoidoscopy-based strategies in a Chinese population.

OBJECTIVE: To compare the performance of existing sigmoidoscopy-based strategies in predicting advanced proximal neoplasia (APN) in an asymptomatic Chinese cohort. DESIGN: We included all screening participants aged 50-70 years who received colonoscopy between 2008 and 2014 in Hong Kong. Sigmoidoscopy yield was estimated from the colonoscopic findings based on the: (1) UK flexible sigmoidoscopy; (2) Screening for COlon REctum (SCORE); (3) NORwegian Colorectal Cancer Prevention (NORCCAP) trials and (4) US clinical index based on age, gender and distal findings. The sensitivity, specificity, the number of subjects needed to screen (NNS) and the number of subjects needed to refer (NNR) for colonoscopy to detect one APN were evaluated. Binary logistic regression modelling identified the distal findings associated with APN. RESULTS: From 5879 eligible subjects, 132 (2.2%) had APN. The US strategy achieved the highest sensitivity for APN detection (42.0%) and the UK criteria attained the highest specificity (96%). The US criteria led to the lowest NNS (92 vs 103-267) and the UK criteria required the least NNR (12 vs 16-21). Using the US strategy, the rates of APN detected were 1.4% (low-risk group), 2.2% (intermediate risk) and 5.9% (high risk). The c-statistics of the UK, SCORE, NORCCAP and the US criteria were 0.55±0.03; 0.59±0.03; 0.59±0.03 and 0.62±0.05 respectively. CONCLUSIONS: The US criteria had the highest sensitivity for detection of APN and lowest NNS and the UK score had the highest specificity and the lowest NNR. The performance of all these four criteria to predict APN is limited, highlighting an urgent need to devise a novel APN prediction system for Asian subjects.

Comparison of colonoscopic performance between medical and nurse endoscopists: a non-inferiority randomised controlled study in Asia.

OBJECTIVE: To test the hypothesis that trained nurse endoscopists are not inferior to medical endoscopists in finding adenomas during colonoscopy. DESIGN: This is a prospective, randomised, single-blind, non-inferiority study comparing nurses with medical endoscopists in performing screening colonoscopy. The nurse endoscopists had been trained according to the British Joint Advisory Group on GI Endoscopy curriculum and had completed at least 140 colonoscopic procedures prior to the study. The primary endpoint was the adenoma detection rate. Secondary endpoints included the caecal intubation rate, intubation time, complication rate, patient pain and satisfaction scores. RESULTS: We enrolled and analysed a total of 731 patients over a 15-month period. At least one adenoma was found in 159 (43.8%) of 363 patients by nurse endoscopists and 120 (32.7%) of 367 patients by medical endoscopists and a proportion difference of +11.1% compared with the medical endoscopists (95% CI 4.1% to 18.1%). The withdrawal time was, however, significantly longer among nurses (998 vs 575 s, p<0.001). After adjusting for differences in a regression analysis, colonoscopy by nurses was associated with a lower adenoma detection rate (OR 0.475: 95% CI 0.311 to 0.725). Nurse endoscopists had a lower caecal intubation rate (97.3% vs 100%), received better pain and satisfaction scores and had a high rate of patient acceptance. CONCLUSIONS: In this pragmatic trial, nurses can perform screening colonoscopy but require a longer procedural time to achieve a comparable adenoma detection rate as medical endoscopists. TRIAL REGISTRATION NUMBER: NCT01923155.

Diagnostic Accuracy of a Qualitative Fecal Immunochemical Test Varies With Location of Neoplasia But Not Number of Specimens.

BACKGROUND & AIMS: We compared the accuracy of a qualitative fecal immunochemical test (FIT) in identifying patients with proximal vs distal advanced neoplasia and evaluated whether analysis of 2 specimens performed better than analysis of 1 specimen. Distal advanced neoplasia was defined as colorectal cancer (CRC), any colorectal adenoma ≥10 mm in diameter, high-grade dysplasia, or a lesion with villous or tubulovillous histologic characteristics in a location distal to the splenic flexure, including the descending colon, the rectosigmoid, and the rectum. METHODS: We collected data from 5343 subjects (50-70 years old) who received 2 FITs (Hemosure; cutoff value, 10 µg hemoglobin/g feces) before colonoscopy in an invitational CRC screening program in Hong Kong from 2008 through 2012. We calculated the FIT's sensitivity, specificity, positive predictive value (PPV), and negative predictive value in detecting colorectal neoplasia. RESULTS: Of the participants, 13.6%, 12.2%, and 6.0% had distal, proximal, and synchronous distal or proximal neoplasia, respectively. Advanced neoplasia was detected in 291 subjects (5.4%); 22 (0.4%) had CRC. FIT detected distal advanced adenoma with 39.7% sensitivity (95% confidence interval [CI], 32.0%-48.0%) vs proximal advanced adenoma with 25.0% sensitivity (95% CI, 17.3%-34.6%; P = .014), distal advanced neoplasia with 40.0% sensitivity (95% CI, 32.5%-47.9%) vs proximal advanced neoplasia with 27.9% sensitivity (95% CI, 20.0%-37.4%; P = .039), and any distal adenoma ≥10 mm, irrespective of other lesion characteristics, with 39.5% sensitivity (95% CI, 31.0%-48.7%) vs. proximal adenoma with 25.3% sensitivity (95% CI, 16.5%-36.6%; P = .038). The specificity of FIT in detecting CRC was similar between the proximal and distal colon. FIT detected distal lesions with higher PPV than proximal lesions. One FIT detected advanced neoplasia with 31.8% sensitivity (95% CI, 25.9%-38.4%) and 92.4% specificity (95% CI, 91.6%-93.2%), whereas 2 FITs detected advanced neoplasia with 34.1% sensitivity (95% CI, 28.0%-40.8%; P = .617) and 91.9% specificity (95% CI, 91.0%-92.7%; P = .327). FIT detected distal advanced neoplasia with greater sensitivity and higher PPV than proximal advanced neoplasia. CONCLUSIONS: In an analysis of data from subjects who underwent CRC screening in Hong Kong, FIT detected distal advanced neoplasia with higher sensitivity than proximal advanced neoplasia. Analysis of 1 vs 2 specimens by FIT identified advanced neoplasia with similar test characteristics.

Factors associated with false-positive and false-negative fecal immunochemical test results for colorectal cancer screening.

BACKGROUND: Certain subgroups have higher rates of false fecal immunochemical test (FIT) results, yet few studies have addressed this topic. OBJECTIVE: To identify demographic factors associated with false-positive and false-negative FIT results in colorectal cancer screening. DESIGN: Retrospective database review of prospectively collected data. SETTING: A bowel cancer screening center in Hong Kong invited participants for colorectal cancer screening (2008-2012). PATIENTS: Study participants who underwent both FIT and colonoscopy in the first year (n = 4482) and underwent colonoscopy after negative FIT results for 3 consecutive years (n = 857). MAIN OUTCOME MEASUREMENTS: The diagnostic accuracy and predictive values of FIT according to participant characteristics. RESULTS: The sensitivity, specificity, positive predictive values, and negative predictive values for advanced neoplasia were 33.1%, 91.9%, 19.0%, and 96.0%, respectively. Participants 66 to 70 years of age had higher sensitivity, whereas older age, smoking, and use of aspirin/nonsteroidal anti-inflammatory drugs were associated with lower specificity. The rates of false-positive and false-negative results were 8.1% and 66.9%, respectively. Older age (66-70 years; adjusted odds ratio [AOR] 1.95; 95% confidence interval [CI], 1.35-2.81; P < .001), smoking (AOR 1.68; 95% CI, 1.08-2.61; P = .020), and the presence of polypoid adenoma (AOR 1.71; 95% CI, 1.14-2.57; P = .009) were associated with false-positive results. Younger participants (AOR for elderly participants 0.31) and the use of aspirin/nonsteroidal anti-inflammatory drugs (AOR 4.44) in participants with 1 FIT with negative results and the absence of high-grade dysplasia (AOR for presence 0.41) were associated with false-negative results. LIMITATIONS: Self-referred participants who received one type of qualitative FIT. CONCLUSION: These findings could be used to target screening more toward those with a higher risk of false-negative results and those with a lower risk of false-positive results for earlier colonoscopy.

A validated tool to predict colorectal neoplasia and inform screening choice for asymptomatic subjects.

OBJECTIVE: We aim to develop and validate a clinical scoring system to predict the risks of colorectal neoplasia to better inform screening participants and facilitate their screening test choice. DESIGN: We recruited 5220 Chinese asymptomatic screening participants who underwent colonoscopy in Hong Kong during 2008-2012. From random sampling of 2000 participants, independent risk factors were evaluated for colorectal neoplasia, defined as adenoma, advanced neoplasia, colorectal cancer or any combination thereof using binary regression analysis. The ORs for significant risk factors were used to develop a scoring system ranging from 0 to 6: 0-2 'average risk' (AR) and 3-6 'high risk' (HR). The other 3220 screening participants prospectively enrolled between 2008 and 2012 for screening colonoscopy formed an independent validation cohort. The performance of the scoring system for predicting colorectal neoplasia was evaluated. RESULTS: The prevalence of colorectal neoplasia in the derivation and validation cohorts was 31.4% and 30.8%, respectively. Using the scoring system developed, 78.9% and 21.1% in the validation cohort were classified as AR and HR, respectively. The prevalence of colorectal neoplasia in the AR and HR groups was 27.1% and 44.6%, respectively. The subjects in the HR group had 1.65-fold (95% CI 1.49 to 1.83) increased prevalence of colorectal neoplasia than the AR group. CONCLUSIONS: The scoring system based on age, gender, smoking, family history, Body Mass Index and self-reported diabetes is useful in predicting the risk of colorectal neoplasia.

Informed choice vs. no choice in colorectal cancer screening tests: a prospective cohort study in real-life screening practice.

OBJECTIVES: The objective of this study was to compare the level of adherence to colorectal cancer (CRC) screening programs among screening participants offered vs. not offered informed choices on screening modality. METHODS: We recruited 10,606 screening participants aged 50-70 years, including 6,397 subjects who were offered a choice of yearly fecal immunochemical test (FIT) for up to 3 years vs. one colonoscopy, and 4,209 subjects who were offered either FIT or colonoscopy without choice. They were prospectively followed up for 3 years. The proportion of screening participants who returned their specimens in all subsequent years (FIT group) and the attendance rate of scheduled endoscopy appointment (colonoscopy group) were compared between those with vs. without choice. RESULTS: The adherence rate with FIT was 97.6%, 84.1%, and 72.6% in the first 3 years of follow-up, respectively, among those who were offered a choice. The adherence rate with FIT was 97.5%, 78.4%, and 62.8%, respectively, among those without choices. The proportion of subjects attending colonoscopy was 95.7% (choice offered) and 90.6% (no choice). From binary logistic regression analysis, participants who were offered informed choice were significantly more likely to adhere to the program when compared with those without test choices (odds ratio (OR)=2.54, 95% confidence interval (CI): 2.30-2.82, P<0.001). The respective adjusted OR for the FIT and colonoscopy groups was 1.60 (95% CI: 1.42-1.80, P<0.001) and 2.53 (95% CI: 1.94-3.31, P<0.001). CONCLUSIONS: This study found that patients who were offered an informed choice for screening had higher adherence rates than patients who were not offered a choice in real-life practices, suggesting that providing screening test options for CRC screening is preferred.

Prospective cohort study of compliance with faecal immunochemical tests for colorectal cancer screening in Hong Kong.

OBJECTIVE: This study aims to examine the rate and determinants of faecal immunochemical test (FIT) compliance over a four-year period among asymptomatic participants in a colorectal cancer (CRC) screening programme in Hong Kong. METHOD: Self-referred screening participants aged between 50 and 70 years who chose FIT for annual screening were followed up for four years (2008-2012). All participants were reminded up to three times yearly for FIT retrieval within two months of the expected screening date. The proportions of screening participants who failed to adhere to annual FIT tests in 1, 2, 3 and 4-years, respectively, after the initial screening uptake were evaluated. The factors associated with non-compliance with FITs in any year were assessed by a binary logistic regression analysis. RESULTS: From 5700 consecutive screening participants, the compliance rates to FIT were 95.1%, 79.9%, 66.2% and 68.4% at years one to four, respectively. The proportions of people missing one, two and three tests were 6.2%, 19.6% and 2.1%, respectively. From multivariate regression analysis, male subjects, younger participants, smokers and those with positive family history of CRC were more likely to be non-compliant. CONCLUSION: Participants identified as at higher risk for screening non-compliance should be especially considered for individual reminders to enhance screening effectiveness.