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.

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.

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.

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.

Changes in the choice of colorectal cancer screening tests in primary care settings from 7,845 prospectively collected surveys.

PURPOSE: Colorectal cancer (CRC) is one of the leading causes of cancer mortality worldwide. This study examined factors influencing the choice of participants between colonoscopy and fecal immunochemical test (FIT) in a screening program and the impact of an unbiased educational session on influencing this decision. METHODS: Data from 7,845 participants who underwent screening between May 2008 and April 2011 was analyzed. Binary logistic regression and multinomial regression were performed to calculate the odds of selection of colonoscopy instead of FIT and the impact of the educational session on final participant choice, respectively. RESULTS: Of the 7,845 participants, 4,796 (61 %) underwent FIT and 3,049 (39 %) underwent colonoscopy. A significant number of participants changed their initial choice after the educational session, with 27.1 % changing to FIT from colonoscopy and 8 % changing from FIT to colonoscopy. Age, educational level, occupation, income, family history of CRC, perception of risk of CRC, and perceptions regarding CRC screening were significantly different among the groups choosing FIT and colonoscopy. Family history of CRC and high self-perception of CRC risk resulted in higher odds of choosing colonoscopy, whereas older age, single marital status, and negative perception of CRC screening resulted in lower odds. Perceptions of overall health status, occupation, low income, younger age, and negative perceptions of CRC screening were associated with higher odds of change in screening choice. CONCLUSIONS: Those at higher odds of changing CRC screening options should be supported with more detailed explanations by primary care physicians to secure a more informed and considered choice.

Poor health literacy associated with stronger perceived barriers to breast cancer screening and overestimated breast cancer risk.

Background: Low health literacy (HL) is negatively associated with mammography screening uptake. However, evidence of the links between poor HL and low mammography screening participation is scarce. Methods: We conducted a cross-sectional questionnaire survey among participants of a cancer screening program. We measured HL using a validated Chinese instrument. We assessed breast cancer screening-related beliefs using the Health Belief Model and the accuracy of risk perception. We used multivariable regression models to estimate the relationship between HL and the outcomes. Results: A total of 821 females were included. 264 (32.2%) had excellent or sufficient, 353 (43.0%) had problematic, and 204 (24.8%) had inadequate health literacy (IHL). Women with IHL were more likely to agree that high price (ß = -0.211, 95% CI -0.354 to -0.069), lack of time (ß = -0.219, 95% CI -0.351 to -0.088), inconvenient service time (ß = -0.291, 95% CI -0.421 to -0.160), long waiting time (ß = -0.305, 95% CI -0.447 to -0.164), fear of positive results (ß = -0.200, 95% CI -0.342 to -0.058), embarrassment (ß = -0.225, 95% CI -0.364 to -0.086), fear of pain (ß = -0.154, 95% CI -0.298 to -0.010), fear of radiation (ß = -0.177, 95% CI -0.298 to -0.056), lack of knowledge on service location (ß = -0.475, 95% CI -0.615 to -0.335), and lack of knowledge on mammography (ß = -0.360, 95% CI -0.492 to -0.228) were barriers. They were also less likely to have an accurate breast cancer risk perception (aOR 0.572, 95% CI 0.341 to 0.956). Conclusion: Women with lower HL could have stronger perceived barriers to BC screening and an over-estimation of their breast cancer risk. Tackling emotional and knowledge barriers, financial and logistical assistance, and guidance on risk perception are needed to increase their breast cancer screening uptake.

Effectiveness of One-Stop Screening for Colorectal, Breast, and Prostate Cancers: A Population-Based Feasibility Study.

Colorectal cancer (CRC), prostate cancer (PC) and breast cancer (BC) are among the most common cancers worldwide with well-established screening strategies. We aim to investigate the effectiveness and compliance of a one-stop screening service for CRC, PC and BC. Asymptomatic subjects aged 50-75 years were invited. Eligible subjects were offered fecal immunochemical test (FIT) for CRC screening. Serum prostate specific antigen (PSA) and Prostate Health Index (PHI) were offered for male PC screening and mammogram (MMG) for female BC screening as a one-stop service. Colonoscopy was offered to FIT+ subjects, prostate biopsy to PSA/PHI+ (PSA>10/PHI≥35) males and breast biopsy to MMG+ (Breast Imaging-Reporting and Data System, BI-RADS≥4) females. From August 2018 to April 2020, 3165 subjects were recruited. All participants (1372 men and 1793 women) were willing to accept FIT for CRC screening, and PSA/PHI test or MMG as second cancer screening. 102 subjects diagnosed advanced neoplasms after colonoscopy. Thirty-three males diagnosed PC after prostate biopsy and 15 females diagnosed BC after breast biopsy. No major complication reported in first tier screening tests. Subjects who were willing to undergo CRC screening were highly likely to accept other cancer screening when offered in a one-stop program. In conclusion, the effectiveness and compliance of a one-stop service for CRC, PC, and BC screening among asymptomatic subjects were high. Future studies should be conducted to test various ways of integrating cancer screening programs. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT04034953.

Accuracy of Faecal Immunochemical Test to Predict Endoscopic and Histological Healing in Ulcerative Colitis: A Prospective Study Based on Validated Histological Scores.

BACKGROUND AND AIMS: Endoscopic and histological healing are associated with improved clinical outcomes in ulcerative colitis [UC]. We aimed to investigate the predictive value of faecal immunochemical test [FIT] for endoscopic and histological healing in UC. METHODS: We measured quantitative FIT and faecal calprotectin [FC] in 140 consecutive UC patients who underwent colonoscopy. We assessed the diagnostic accuracy of FIT for predicting endoscopic healing using the Mayo endoscopic subscore [MES 0/1] and for histological healing using the Geboes score [< 2.0] and Nancy index [grade ≤ 1]. The predictive abilities of FIT were compared with those of FC. RESULTS: FIT had an area under the curve [AUC] of 0.77 (95% confidence interval [CI] 0.67-0.86, p < 0.001) for endoscopic healing, an AUC of 0.77 [95% CI 0.67-0.86, p < 0.001] using the Geboes score, and 0.77 [95% CI 0.66-0.85, p < 0.001] using the Nancy Index for histological healing. The AUC of FIT was comparable to that of FC for endoscopic healing [p = 0.773] and histological healing [p = 0.767-0.960], and was comparable to colonoscopy for histological healing [p = 0.384-0.673]. FIT < 50 ng/ml predicted endoscopic healing with a sensitivity, specificity, and positive predictive value [PPV] of 72%, 68%, and 82%, respectively, and for histological healing with a sensitivity, specificity, and PPV of 73-75%, 67%, and 78-80%, respectively. Combining FIT with FC led to a higher specificity [90%] for histological healing. Over 85% of patients with FIT < 50 ng/ml and FC < 50 µg/g achieved histological healing. CONCLUSIONS: FIT is highly sensitive and accurate to predict endoscopic and histological healing in UC. It represents a promising non-invasive tool for monitoring mucosal healing in UC.

Colorectal Cancer Screening Based on Age and Gender: A Cost-Effectiveness Analysis.

We evaluated whether age- and gender-based colorectal cancer screening is cost-effective.Recent studies in the United States identified age and gender as 2 important variables predicting advanced proximal neoplasia, and that women aged <60 to 70 years were more suited for sigmoidoscopy screening due to their low risk of proximal neoplasia. Yet, quantitative assessment of the incremental benefits, risks, and cost remains to be performed.Primary care screening practice (2008-2015).A Markov modeling was constructed using data from a screening cohort. The following strategies were compared according to the Incremental Cost Effectiveness Ratio (ICER) for 1 life-year saved: flexible sigmoidoscopy (FS) 5 yearly; colonoscopy 10 yearly; FS for each woman at 50- and 55-year old followed by colonoscopy at 60- and 70-year old; FS for each woman at 50-, 55-, 60-, and 65-year old followed by colonoscopy at 70-year old; FS for each woman at 50-, 55-, 60-, 65-, and 70-year old. All male subjects received colonoscopy at 50-, 60-, and 70-year old under strategies 3 to 5.From a hypothetical population of 100,000 asymptomatic subjects, strategy 2 could save the largest number of life-years (4226 vs 2268 to 3841 by other strategies). When compared with no screening, strategy 5 had the lowest ICER (US$42,515), followed by strategy 3 (US$43,517), strategy 2 (US$43,739), strategy 4 (US$47,710), and strategy 1 (US$56,510). Strategy 2 leads to the highest number of bleeding and perforations, and required a prohibitive number of colonoscopy procedures. Strategy 5 remains the most cost-effective when assessed with a wide range of deterministic sensitivity analyses around the base case.From the cost effectiveness analysis, FS for women and colonoscopy for men represent an economically favorable screening strategy. These findings could inform physicians and policy-makers in triaging eligible subjects for risk-based screening, especially in countries with limited colonoscopic resources. Future research should study the acceptability, feasibility, and feasibility of this risk-based strategy in different populations.

The discriminatory capability of existing scores to predict advanced colorectal neoplasia: a prospective colonoscopy study of 5,899 screening participants.

We evaluated the performance of seven existing risk scoring systems in predicting advanced colorectal neoplasia in an asymptomatic Chinese cohort. We prospectively recruited 5,899 Chinese subjects aged 50-70 years in a colonoscopy screening programme(2008-2014). Scoring systems under evaluation included two scoring tools from the US; one each from Spain, Germany, and Poland; the Korean Colorectal Screening(KCS) scores; and the modified Asia Pacific Colorectal Screening(APCS) scores. The c-statistics, sensitivity, specificity, positive predictive values(PPVs), and negative predictive values(NPVs) of these systems were evaluated. The resources required were estimated based on the Number Needed to Screen(NNS) and the Number Needed to Refer for colonoscopy(NNR). Advanced neoplasia was detected in 364 (6.2%) subjects. The German system referred the least proportion of subjects (11.2%) for colonoscopy, whilst the KCS scoring system referred the highest (27.4%). The c-statistics of all systems ranged from 0.56-0.65, with sensitivities ranging from 0.04-0.44 and specificities from 0.74-0.99. The modified APCS scoring system had the highest c-statistics (0.65, 95% C.I. 0.58-0.72). The NNS (12-19) and NNR (5-10) were similar among the scoring systems. The existing scoring systems have variable capability to predict advanced neoplasia among asymptomatic Chinese subjects, and further external validation should be performed.

Determinants of Bowel Preparation Quality and Its Association With Adenoma Detection: A Prospective Colonoscopy Study.

The predictors of poor bowel preparation in colorectal cancer screening participants have not been adequately studied, and the association between the quality of bowel preparation and adenoma detection has not been firmly established. This study examined the determinants of poor bowel preparation, and evaluated its relationship with adenoma detection.We included subjects aged between 50 and 70 years who received colonoscopy between 2008 and 2014 in a colorectal cancer screening program in Hong Kong. The quality of the bowel preparation was assessed by colonoscopists, and the factors associated with poor bowel cleansing were evaluated by a binary logistic regression analysis. A multivariate regression model was constructed to evaluate if poor bowel preparation was associated with detection of colorectal neoplasia.From 5470 screening participants (average age 57.7 years, SD 4.9), 1891 (34.6%) had poor or fair bowel preparation. The average cecal intubation time was 7.0 minutes (SD 5.4; range 1.22-36.9 minutes) and the average colonoscopy withdrawal time was 10.8 minutes (SD 6.9; range 6.0-107.0 minutes). Among all, 26.5% had colorectal neoplasia and 5.5% had advanced neoplasia. Older age (≥60 years; adjusted odds ratio [AOR] = 1.19-1.38, P = 0.02-0.04), male sex (AOR = 1.38, 95% confidence interval [CI] 1.19-1.60, P < 0.001), and current smoking (AOR = 1.41, 95% CI 1.14-1.75, P = 0.002) were significantly associated with poor/fair bowel preparation. Poorer cleansing resulted in significantly lower detection rate of neoplasia (AOR = 0.35-0.62) and advanced neoplasia (AOR = 0.36-0.50) irrespective of polyp size.Steps to improve proper procedures of bowel preparation are warranted, especially among subjects at risk of poor bowel preparation. Strategies should be implemented to improve bowel cleansing, which is now demonstrated as a definite quality indicator.

Validation of a risk prediction score for proximal neoplasia in colorectal cancer screening: a prospective colonoscopy study.

This study developed a clinical scoring system to predict the risks of PN among screening participants for colorectal cancer. We recruited 5,789 Chinese asymptomatic screening participants who received colonoscopy in Hong Kong (2008-2014). From random sampling of 2,000 participants, the independent risk factors were evaluated for PN using binary regression analysis. The odds ratios for significant risk factors were used to develop a scoring system, with scores stratified into 'average risk' (AR):0-2 and 'high risk' (HR):3-5. The other 3,789 subjects formed an independent validation cohort. Each participant received a score calculated based on their risk factors. The performance of the scoring system was evaluated. The proportion of PN in the derivation and validation cohorts was 12.6% and 12.9%, respectively. Based on age, gender, family history, body mass index and self-reported ischaemic heart disease, 85.0% and 15.0% in the validation cohort were classified as AR and HR, respectively. Their prevalence of PN was 12.0% and 18.1%, respectively. Participants in the HR group had 1.51-fold (95% CI = 1.24-1.84, p < 0.001) higher risk of PN than the AR group. The overall c-statistics of the prediction model was 0.71(0.02). The scoring system is useful in predicting the risk of PN to prioritize patients for colonoscopy.

Regret on choice of colorectal cancer screening modality was associated with poorer screening compliance: a 4-year prospective cohort study.

PURPOSE: Very few studies examined the issue of regret on choosing colorectal cancer (CRC) screening tests. We evaluated the determinants of regret and tested the hypothesis that regret over screening choices was associated with poorer screening compliance. METHODS: A bowel cancer screening centre invited all Hong Kong citizens aged 50-70 years who were asymptomatic of CRC to participate in free-of-charge screening programmes. Upon attendance they attended health seminars on CRC and its screening, and were offered an option to choose yearly faecal immunochemical test (FIT) for up to four years vs. one direct colonoscopy. They were not allowed to switch the screening option after decision. A self-administered, four-item validated survey was used to assess whether they regretted over their choice (> 2 = regretful from a scale of 0 [no regret]-5 [extreme regret]). A binary logistic regression model evaluated if initial regret over their choice was associated with poorer programme compliance. RESULTS: From 4,341 screening participants who have chosen FIT or colonoscopy, 120 (2.8%) regretted over their decision and 1,029 (23.7%) were non-compliant with the screening programme. Younger subjects and people who felt pressure when making their decision were associated with regret. People who regretted their decision were 2.189 (95% C.I. 1.361-3.521, p = 0.001) times more likely to be non-compliant with the programme. CONCLUSIONS: This study is the first to show that regret over the initial CRC screening choice was associated with later non-compliance. Screening participants who expressed regret over their choice should receive additional reminders to improve their programmatic compliance.

Identification of subjects at risk of proximal advanced neoplasia for colorectal cancer screening.

Flexible sigmoidoscopy (FS) and colonoscopy are two commonly used screening tools for colorectal cancer (CRC), and FS mainly detects distal lesions. Colonoscopy resource is limited, yet there is no definite evidence on when flexible sigmoidoscopy is suitable as a screening alternative. This study evaluated the optimal cut-off score from a validated risk stratification system which best predicts proximal advanced neoplasia (PAN) by comparing the sensitivity, specificity and relative risk of PAN according to various cut-off scores. 5819 asymptomatic subjects aged between 50 and 70years (average age 57.7years, standard deviation (SD) 4.9) received colonoscopy between 2008 and 2014 in Hong Kong. Their prevalence of PAN was evaluated according to a prediction tool for colorectal neoplasia based on age, gender, smoking status, family history of CRC, body mass index (BMI) and diabetes (ranging from 0 to 6). One binary logistic regression model was performed with PAN as the outcome variable and the risk score as the variable tested for association. In multivariate regression analysis, risk score ⩾3 was associated with significantly higher risk of PAN (3.4-9.1%; AOR=3.18-8.09, p<0.001) when compared with those scoring 0. Risk scores 0-2 were associated with either insignificant or lower risks of PAN compared to the overall risk. Applying FS for screening those who scored 0-2 and colonoscopy for those who scored ⩾3 led to a very small proportion of PAN being missed (1.60%), whilst maintaining a high level of specificity (81.9%). Clinicians may use this scoring system to inform subjects and facilitate their choice between colonoscopy and FS.

Should prior FIT results be incorporated as an additional variable to estimate risk of colorectal neoplasia? A prospective study of 5,813 screening colonoscopies.

BACKGROUND: Recent studies showed that previous negative results from faecal immunochemical tests (FITs) for colorectal cancer (CRC) screening was associated with lower risk of advanced neoplasia (AN). We evaluated whether prior FIT results should be included to estimate the risk of AN in 2008-2012. METHODS: A community-based screening practice recruited 5,813 asymptomatic residents aged 50 to 70 years in Hong Kong for CRC screening. We included study participants who had (1). positive FIT with subsequent colonoscopy workup (FIT+ group; n = 356); (2). negative FIT in three consecutive years and received a colonoscopy (FIT- group; n = 857); (3). received colonoscopy without FIT (colonoscopy group; n = 473); and (4). received both colonoscopy and FIT at the same time (combined group; n = 4,127). One binary logistic regression model evaluated whether prior FIT results were associated with colonoscopy findings of AN. RESULTS: The proportion of participants having AN/CRC was 18.0% (FIT+), 5.5% (FIT-), 8.0% (colonoscopy group), and 4.3% (combined group), respectively. When compared with the colonoscopy group, those in the FIT- group were not significantly more or less likely to have AN/CRC (AOR = 0.77, 95% C.I. = 0.51 to 1.18, p = 0.230). Having one (AOR = 0.73, 95% C.I. 0.48-1.12, p = 0.151) or three consecutive negative FIT result (AOR = 0.98, 95% C.I. 0.60-1.62, p = 0.944) were not associated with lower risks of AN/CRC. Subjects in the FIT+ group was 3.32-fold (95% C.I. 2.07 to 5.32, p < 0.001) more likely to have AN/CRC. CONCLUSIONS: These findings indicated that subjects with negative FIT findings could be risk stratified similarly as those who had not previously received FIT.