Asia-Pacific Colorectal Screening Research Articles

Development and evaluation of a risk prediction tool for risk-adapted screening of colorectal cancer in China

Risk prediction tools for colorectal cancer (CRC) have potential to improve the efficiency of population-based screening by facilitating risk-adapted strategies. However, such an applicable tool has yet to be established in the Chinese population. In this study, a risk score was created using data from the China Kadoorie Biobank (CKB), a nationwide cohort study of 409,854 eligible participants. Diagnostic performance of the risk score was evaluated in an independent CRC screening programme, which included 91,575 participants who accepted colonoscopy at designed hospitals in Zhejiang Province, China. Over a median follow-up of 11.1 years, 3136 CRC cases were documented in the CKB. A risk score was created based on nine questionnaire-derived variables, showing moderate discrimination for 10-year CRC risk (C-statistic = 0.68, 95 % CI: 0.67–0.69). In the CRC screening programme, the detection rates of CRC were 0.25 %, 0.82 %, and 1.93 % in low-risk (score <6), intermediate-risk (score: 6–19), and high-risk (score >19) groups, respectively. The newly developed score exhibited a C-statistic of 0.65 (95 % CI: 0.63–0.66), surpassing the widely adopted tools such as the Asia-Pacific Colorectal Screening (APCS), modified APCS, and Korean Colorectal Screening scores (all C-statistics = 0.60). In conclusion, we developed a novel risk prediction tool that is useful to identify individuals at high risk of CRC. A user-friendly online calculator was also constructed to encourage broader adoption of the tool.

Performance of the Asia-Pacific Colorectal Screening score in stratifying the risk of advanced colorectal neoplasia: A meta-analysis and systematic review.

This study systematically reviewed and meta-analyzed the performance of the Asia-Pacific Colorectal Screening (APCS) score and its incorporation with the fecal immunochemical test (FIT) in stratifying the risk of advanced colorectal neoplasia (ACN). We systematically searched for relevant articles in 12 electronic databases and registers on October 20, 2021, and updated the search to September 1, 2023. Random-effect models were used to obtain the pooled performance statistics of the APCS score for ACN risk. From the 101 records screened, 13 eligible studies in the Asia-Pacific region involving 69762 subjects who had undergone colonoscopy were enrolled. The pooled prevalences of ACN in the average-risk (AR) tier (APCS 0-1), moderate-risk (MR) tier (APCS 2-3), and high-risk (HR) tier (APCS≥4) groups were 0.9%, 3.1%, and 8.1%, respectively. Compared with the combined AR-MR group, the HR group was significantly associated with a higher ACN risk (pooled diagnostic odds ratio: 2.84, 95% confidence interval [CI]: 2.35-3.45, P<0.001). The APCS score showed a sensitivity of 0.42 (95% CI: 0.40-0.44) and a specificity of 0.86 (95% CI: 0.85-0.86) for predicting the ACN risk, with a weighted area under the curve of 0.642 (95% CI: 0.610-0.657). The combination of the APCS score and FIT substantially improved ACN risk identification, demonstrating pooled diagnostic odds ratios of 4.02 (95% CI: 2.50-6.49) in the AR-MR groups and 5.44 (95% CI: 1.89-15.63) in the MR-HR groups. The APCS score could effectively stratify the ACN risk in the Asia-Pacific population. Incorporating FIT further improves its performance in identifying high-risk subjects who should be prioritized for colonoscopy screenings.

Developing a Nomogram for Predicting Colorectal Cancer and Its Precancerous Lesions Based on Data from Three Non-Invasive Screening Tools, APCS, FIT, and sDNA.

This study aimed to develop and validate a nomogram for predicting positive colonoscopy results using the data from non-invasive screening strategies. The volunteers participated in primary colorectal cancer (CRC) screenings using Asia-Pacific colorectal screening (APCS) scoring, faecal immunochemical testing (FIT) and stool deoxyribonucleic acid (sDNA) testing and underwent a colonoscopy. The positive colonoscopy results included CRC, advanced adenoma (AA), high-grade intraepithelial neoplasia (HGIN), and low-grade intraepithelial neoplasia (LGIN). The enrolled participants were randomly selected for training and validation sets in a 7:3 ratio. A model for predicting positive colonoscopy results was virtualized by the nomogram using logistic regression analysis. Among the 179 enrolled participants, 125 were assigned to training set, while 54 were assigned to validation set. After multivariable logistic regression was done, APCS score, FIT result, and sDNA result were all identified as the predictors for positive colonoscopy results. A model that incorporated the above independent predictors was developed and presented as a nomogram. The C-index of the nomogram in the validation set was 0.768 (95% CI, 0.644-0.891). The calibration curve demonstrated a good agreement between prediction and observation. The decision curve analysis (DCA) curve showed that the model achieved a net benefit across all threshold probabilities. The AUC of the prediction model for predicting positive colonoscopy results was much higher than that of the FIT + sDNA test scheme. The nomogram for predicting positive colonoscopy results was successfully developed based on 3 non-invasive screening tools (APCS scoring, FIT and sDNA test).

An adjusted Asia-Pacific colorectal screening score system to predict advanced colorectal neoplasia in asymptomatic Chinese patients

PurposeThe Asia-Pacific Colorectal Screening (APCS) score and its derivatives have been used to predict advanced colorectal neoplasia (ACN). However, it remains unknown whether they apply to the current Chinese population in general clinical practice. Therefore, we aimed to update the APCS score system by applying data from two independent asymptomatic populations to predict the risk of ACN in China.MethodsWe developed an adjusted APCS (A-APCS) score by using the data of asymptomatic Chinese patients undergoing colonoscopies from January 2014 to December 2018. Furthermore, we validated this system in another cohort of 812 patients who underwent screening colonoscopy between January and December 2021. The discriminative calibration ability of the A-APCS and APCS scores was comparatively evaluated.ResultsUnivariate and multivariate logistic regression were applied to assess the risk factors for ACN, and an adjusted scoring system of 0 to 6.5 points was schemed according to the results. Utilizing the developed score, 20.2%, 41.2%, and 38.6% of patients in the validation cohort were classified as average, moderate, and high risk, respectively. The corresponding ACN incidence rates were 1.2%, 6.0%, and 11.1%, respectively. In addition, the A-APCS score (c-statistics: 0.68 for the derivation and 0.80 for the validation cohort) showed better discriminative power than using predictors of APCS alone.ConclusionsThe A-APCS score may be simple and useful in clinical applications for predicting ACN risk in China.

Paper-Based versus Mobile Apps for Colorectal Cancer Screening in COVID-19 Pandemic Setting

Background: The incidence of colorectal cancer (CRC) in Asia has kept increasing in the last decade. The morbidity and mortality for CRC can be reduced with early detection; however, mass CRC screening with imaging modalities such as colonoscopy, CT scan, or MRI is unfeasible in developing countries such as Indonesia. Asia Pacific Colorectal Screening (APCS) is utilized to stratify individual CRC risk. Online screening via mobile application is an alternative method to ensure the continuity of community screening without risking COVID-19 transmission. Objective: We conducted a descriptive study to evaluate CRC risk using APCS in two different villages. Methods: This is a cross-sectional study involving 925 and 207 subjects in 2019 and 2020, respectively. The APCS survey in 2019 was done before the COVID-19 pandemic with paper-based questionnaires and direct assessment by door-to-door approach. Meanwhile, the APCS survey in 2020 was done during the COVID-19 pandemic using websites and mobile apps available for Android and iOS. We gathered participants’ characteristics and the APCS score in both groups and tabulated them. Results: In 2019, out of 925 subjects; 472 (51%) have been classified an average risk of CRC, 370 (40%) have been classified as having a moderate risk of CRC, and 83 (9%) have been classified as in high risk of CRC. In 2020, out of 207 subjects; 106 (51.2%) have been classified as the average risk of CRC, 86 (41.5%) have been classified as the moderate risk of CRC, and 15 (7.3%) have been classified as high risk of CRC. Conclusion: Although there was a decrease in the participation of the screening program with mobile applications in the pandemic era compared with paper-based questionnaires before the pandemic era, online screening using APCS in mobile applications is a preferred alternative for an effective screening method in this pandemic and possibly in the future in Indonesia.

A Comparison of Single and Combined Schemes of Asia-Pacific Colorectal Screening, Faecal Immunochemical and Stool Deoxyribonucleic Acid Testing for Community Colorectal Cancer Screening.

To compare the screening efficacy of colonoscopy and pathologically confirmed single and combined Asia-Pacific colorectal screening (APCS), faecal immunochemical testing (FIT) and stool deoxyribonucleic acid (sDNA) testing protocols. From April 2021 to April 2022, 842 volunteers participated in primary colorectal cancer (CRC) screenings using APCS scoring, FIT and sDNA testing and 115 underwent a colonoscopy. One hundred high-risk participants were then identified from the results of both processes. The differences in the three CRC screening tests in combination with the colonoscopy pathology diagnostics were evaluated using Cochran's Q test, the Dunn-Bonferroni test and area under the receiver operating characteristic curve (AUC) value analysis. Both FIT and sDNA testing demonstrated a 100% performance in detecting CRC. For advanced adenoma, the sensitivity of the FIT + sDNA test scheme (double positive) was 29.2%, and the sensitivities of the combined FIT + sDNA test and APCS scoring + sDNA test schemes were 62.5% and 95.8%, respectively. The FIT + sDNA testing kappa value of advanced colorectal neoplasia was 0.344 (p = 0.011). The sensitivity for nonadvanced adenoma of the APCS score + sDNA test scheme was 91.1%. In terms of positive results, the sensitivity of the APCS score + FIT + sDNA detection protocol was significantly higher than that of the APCS score, FIT, sDNA detection, and FIT + sDNA detection methods (adjusted p < 0.001, respectively). For the FIT + sDNA test, the kappa value was 0.220 (p = 0.015) and the AUC was 0.634 (p = 0.037). The specificity of the FIT + sDNA test scheme was 69.0%. The FIT + sDNA test scheme demonstrated superior diagnostic efficacy, and the combined APCS score + FIT + sDNA test scheme demonstrated remarkable improvements in CRC screening efficiency and sensitivity for detecting positive lesions.

Asia-Pacific Colorectal Screening Score Combined With Stool DNA Test Improves the Detection Rate for Colorectal Advanced Neoplasms

The Asia-Pacific Colorectal Screening (APCS) scoring system was developed to stratify the risk of colorectal advanced neoplasm (AN). We aimed to evaluate the performance of the APCS score combined with a stool DNA test used for colorectal cancer screening. A total of 2842 subjects who visited outpatient clinics or cancer screening centers were enrolled. Age, sex, smoking status, and family history were recorded and APCS scores were calculated in 2439 participants. A stool DNA test (SDC2 and SFRP2 tests) and fecal immunochemical test (FIT) were performed and colonoscopy was used as the gold standard among 2240 subjects who completed all study procedures. We used a threshold of 4.4 μg/g for the FIT, in addition to the manufacturer's recommended threshold of 20 μg/g to match the specificity of a stool DNA test. Based on the APCS score, 38.8% (946 of 2439) of the subjects were categorized as high risk, and they had a 1.8-fold increase in risk for AN (95% CI, 1.4-2.3) compared with low and moderate risk. The APCS combined with the stool DNA test detected 95.2% of invasive cancers (40 of 42) and 73.5% of ANs (253 of 344), while the colonoscopy workload was only 47.1% (1056 of 2240). The sensitivity for AN of APCS combined with stool DNA test was significantly higher than that of APCS combined with FIT (73.5% vs 62.8% with FIT cut-off value of 20 μg/g, and 73.5% vs 68.0% with FIT cut-off value of 4.4 μg/g; both P < .01). The APCS score combined with a stool DNA test significantly improved the detection of colorectal ANs, while limiting colonoscopy resource utilization (Chictr.org.cn, ChiCTR-DDD-17011169).

Validation of the Asia-Pacific colorectal screening score and its modified versions in predicting colorectal advanced neoplasia in Chinese population

BackgroundColorectal cancer is one of the most common cancers in the world. Several studies suggest using the Asia-Pacific colorectal screening (APCS) score and its modified versions to select high-risk populations for early colonoscopy, but external validation remains rare, and which score should be selected for CRC screening in China is unclear. Validation of multiple scores in the same population might help to choose the best performing score.MethodsWe conducted a cross-sectional study under the framework of Cancer Screening Program in Urban China, data from asymptomatic colorectal cancer screening in Xuzhou was used to validate the APCS score, the colorectal neoplasia predict (CNP) score, the Korean colorectal screening (KCS) score, the Modified APCS score and the 8-point risk score in predicting colorectal advanced neoplasia (CAN).Results1804 subjects were included in the analysis and 112 CAN (6.21%) was detected. In each score, the detection rate of CAN was higher in the high-risk group than in the non-high-risk group (P < 0.05), and the RR (95%C.I.) ranged 2.20 (1.50–3.22) [8-point risk] to 4.00 (2.41–6.65) [Modified APCS]. The c-statistics (95%C.I.) of the scoring systems ranged from 0.58 (0.53–0.62) [8-point risk] to 0.65 (0.61–0.69) [KCS]. The sensitivity (95%C.I.) of these systems ranged from 31.25 (22.83–40.70) [8-point risk] to 84.82 (76.81–90.90) [Modified APCS], while the specificity (95%C.I.) ranged from 43.50 (41.12–45.90) [Modified APCS] to 83.81 (81.96–85.53) [8-point risk]. Using the APCS scoring system as a comparator, the net reclassification improvement (NRI) of each modified version ranged from − 10.34% (95%C.I.: − 22.63 to 1.95%) [8-point risk] to 4.79% (95%C.I.: − 1.50% to 11.08) [KCS]. The colonoscopy resource load (95%C.I.) ranged from 9 [1–3] [8-point risk] to 11 [3–5] [APCS and Modified APCS].ConclusionsThe APCS score and its modified versions have certain ability to predict the risk of advanced neoplasia and reduce the resource load. The modified APCS score and the KCS score seemed the preferable systems to classify high risk subjects based on its high RR, sensitivity and predictive ability in the selected population. Future research could focus on adding risk factors or combining with laboratory test results to improve the predictive power of the scoring system.

Efficacy comparison among high risk factors questionnaire and Asia-Pacific colorectal screening score and their combinations with fecal immunochemical test in screening advanced colorectal tumor

Efficacy comparison among high risk factors questionnaire and Asia-Pacific colorectal screening score and their combinations with fecal immunochemical test in screening advanced colorectal tumor

Preliminary application of the Asia-Pacific colorectal screening score combined with the quantitative fecal occult blood in colorectal neoplasia screening

To evaluate the efficacy of the Asia-Pacific colorectal screening (APCS) score combined with the quantitative fecal immunochemical test in colorectal neoplasia screening. Subjects who appointment to receive colonoscopy were recruited from August 2017 to May 2019 in the digestive endoscopy center. Before the colonoscopy, all subjects were scored by the Asia Pacific colorectal cancer screening scoring system and measured by quantitative fecal immunochemical test (QFIT). The detection rates of colorectal neoplasia were compared to evaluate the efficacy of the combined assay in colorectal neoplasia screening between APCS score and QFIT. A total of 1 420 subjects were enrolled in this study, APCS score medium-risk (MR) and high-risk (HR) groups were 847 (59.7%) and 573 (40.4%) and 26 cases (1.8%) of colorectal cancer, 196 cases (13.8%) of advanced adenoma, and 395 cases (27.8%) of non-advanced adenoma were detected. With the combination of APCS score and QFIT, participants were classified into 4 groups high-risk with positive QFIT result group G1, high-risk with negative QFIT result group G2, medium-risk with positive QFIT group G3, medium-risk negative QFIT group G4. The prevalence of colorectal neoplasia was 64.3%, 16.4%, 55.0%, and 9.8%, respectively. The prevalence of advanced neoplasia in high-risk with QFIT results was significantly higher than that in other 3 groups. HR and positive QFIT were the indicators for further colonoscopy, and MR with FIT negative group could postpone colonoscopy and conduct annual QFIT follow-up. The combination of APCS score and QFIT for colorectal neoplasia screening can reduce unnecessary colonoscopy, improve colonoscopy compliance and screening efficiency, and has important clinical significance and promotion value in colorectal tumor screening.

The classification capability of the Asia Pacific Colorectal Screening score in Korea: an analysis of the Cancer Screenee Cohort.

OBJECTIVESThis study aimed to validate a simple risk assessment tool for estimating the advanced colorectal neoplasia (ACN) risk at colonoscopy screenings and potential factors relevant for implementing this tool in the Korean population.METHODSOur study analyzed data from the Cancer Screenee Cohort Study conducted by the National Cancer Center in Korea. The risk level was assessed using the Asia Pacific Colorectal Screening (APCS) score developed by the Asia-Pacific Working Group on Colorectal Cancer. Logistic regression models were used to examine the associations between colorectal-related outcomes and the risk level by APCS score. The discriminatory performance of the APCS score for various colorectal-related outcomes was assessed using C-statistics.RESULTSIn 12,520 individuals, 317 ACN cases and 4,528 adenoma cases were found. The APCS tool successfully classified the study population into different risk groups, and significant differences in the ACN rate and other outcomes were observed. The APCS score demonstrated acceptable discrimination capability with area under the curve values ranging from 0.62 to 0.65 for various outcomes. The results of the multivariate logistic regression model revealed that the high-risk group had a 3.1-fold higher risk of ACN (95% confidence interval, 2.08 to 4.67) than the average-risk group. Body mass index (BMI) was identified as a significant predictor of ACN in both multivariate and subgroup analyses.CONCLUSIONSOur study highlighted significant differences in colorectal-related screening outcomes by colorectal risk level measured using the APCS score, and BMI could be used to improve the discriminatory capability of the APCS score.

Leveraging Fecal Microbial Markers to Improve the Diagnostic Accuracy of the Fecal Immunochemical Test for Advanced Colorectal Adenoma.

INTRODUCTION:Fecal immunochemical tests (FITs) detect colorectal adenoma inefficiently. The gut microbiota participates in colorectal cancer development. We aimed to explore fecal microbial signatures for advanced adenomas and evaluate their diagnostic value and complementary capacity to FIT.METHODS:Using 16S rRNA sequencing, we studied gut microbiota in feces from 1,546 subjects in a screening setting, including 268 patients with advanced adenomas, 490 patients with nonadvanced adenomas, and 788 healthy subjects. Feature selections were performed using linear discriminant analysis effect size, multivariate association with linear models, and least absolute shrinkage and selection operator. The diagnostic performance of microbial signatures and their auxiliary role to FITs and the added value of the Asia-Pacific Colorectal Screening score were evaluated. We applied 0.632+ bootstrapping to adjust the potential overfitting.RESULTS:We identified 13 microbial signatures to show the joint diagnostic value for advanced adenoma, with genus Tyzzerella 4 demonstrating the highest adjusted area under the curve (AUC) of 0.545 (95% confidence interval [CI], 0.520–0.610). The 13-bacteria increased the adjusted AUC to 0.607 (95% CI, 0.548–0.660). Compared with individual FIT (adjusted AUC = 0.527; 95% CI, 0.519–0.571), 13-bacteria and FITs collectively reached an adjusted AUC of 0.641 (95% CI, 0.579–0.691). At cutoff values yielding specificities of 90% and 80%, the adjusted sensitivities were 28.4% (95% CI, 19.3–36.8) and 41.1% (95% CI, 29.9–49.4), respectively. The Asia-Pacific Colorectal Screening score further boosted the adjusted AUC to 0.706 (95% CI, 0.648–0.750).DISCUSSION:In this study using fecal samples from a screening setting, the identified microbial signatures could complement FITs for detecting advanced adenomas. Gut microbiota can act as a promising tool to optimize the current colorectal cancer screening modalities.

Optimizing Positivity Thresholds for a Risk-Adapted Screening Strategy in Colorectal Cancer Screening.

INTRODUCTION:Risk-adapted screening combining the Asia-Pacific Colorectal Screening score, fecal immunochemical test (FIT), and colonoscopy improved the yield of colorectal cancer screening than FIT. However, the optimal positivity thresholds of risk scoring and FIT of such a strategy warrant further investigation.METHODS:We included 3,407 participants aged 50–74 years undergoing colonoscopy from a colorectal cancer screening trial. For the risk-adapted screening strategy, subjects were referred for subsequent colonoscopy or FIT according to their risk scores. Diagnostic performance was evaluated for FIT and the risk-adapted screening method with various positivity thresholds. Furthermore, a modeled screening cohort was established to compare the yield and cost using colonoscopy, FIT, and the risk-adapted screening method in a single round of screening.RESULTS:Risk-adapted screening method had higher sensitivity for advanced neoplasm (AN) (27.6%–76.3% vs 13.8%–17.3%) but lower specificity (46.6%–90.8% vs 97.4%–98.8%) than FIT did. In a modeled screening cohort, FIT-based screening would be slightly affected because the threshold varied with a reduction of 76.0%–80.9% in AN detection and 82.0%–84.4% in cost when compared with colonoscopy. By contrast, adjusting the threshold of Asia-Pacific Colorectal Screening score from 3 to 5 points for risk-adapted screening varied from an increase of 12.6%–14.1% to a decrease of 55.6%–60.1% in AN detection, with the reduction of cost from 4.2%–5.3% rising to 66.4%–68.5%.DISCUSSION:With an appropriate positivity threshold tailored to clinical practice, the risk-adapted screening could save colonoscopy resources and cost compared with the colonoscopy-only and FIT-only strategies.

Current Status of Colorectal Cancer and Its Public Health Burden in Thailand

Colorectal cancer (CRC) accounts for approximately 10.3% of new cancer cases in Thailand and is currently the 3rd most prevalent cancer found among the Thai population. Starting in 2017, the Thai government announced the national CRC screening program as a response to this important issue. Among the 70 million people currently residing in Thailand, 14 million require screening, while there are approximately a total of 1,000 endoscopists available to perform colonoscopy. Due to the limited resources and shortage of endoscopists in Thailand, applying a population-based one-step colonoscopy program as a primary screening method is not feasible. To reduce colonoscopy workload, with the help of others, including village health volunteers, institution-based health personnel, reimbursement coders, pathologists, and patients due for CRC screening, a two-step approach of one-time fecal immunochemical test (FIT), which prioritizes and filters out subjects for colonoscopy, is chosen. Moreover, additional adjustments to the optimal FIT cutoff value and the modified Asia-Pacific Colorectal Screening risk score, including body weight, were proposed to stratify the priority of colonoscopy schedule. This article aims to give an overview of the past and current policy developmental strategies and the current status of the Thailand CRC screening program.

Leveraging Fecal Microbial Markers to Improve the Diagnostic Accuracy of the Fecal Immunochemical Test for Advanced Colorectal Adenoma

Background: Fecal immunochemical tests (FIT) detect colorectal adenoma inefficiently. Alterations in the gut microbiota were associated with the colorectal cancer (CRC) development. We aimed to explore fecal microbial signatures for advanced colorectal adenomas and evaluate their individual diagnostic value and complementary capacity to FIT. Methods: We recruited 1,546 subjects from a CRC screening program, including 268 advanced adenomas, 490 non-advanced adenomas, and 788 healthy subjects. We used a 16S rRNA sequencing based microbiome approach to profile the global microbial composition in fecal samples. Three approaches were applied to feature selections. Receiver operating characteristic (ROC) curves were used to evaluate diagnostic values of microbial signatures and their auxiliary role to FIT and risk-stratified Asia-Pacific Colorectal Screening (APCS) score. We applied ·632+ bootstrapping to adjust the potential overfitting of the prediction models. Findings: We identified 13 microbial signatures showing their joint diagnostic value for advanced adenoma, with genus Tyzzerella 4 demonstrating the highest adjusted area under the curve (AUC) of 0 · 545 (95% CI, 0·520-0·610). A 13-marker classifier was constructed and increased the adjusted AUC to 0·607 (95% CI, 0·548-0·660). Compared with FIT solely, the combination of 13-bacteria panel and FIT reached a promising adjusted AUC of 0·641 (95% CI, 0·579-0·691). At cut-off values yielding specificities of 90% and 80%, the adjusted sensitivities were 28·4% (95% CI, 19·3%-36·8%) and 41.1% (95% CI, 29·9%-49·4%), respectively . APCS score further boosted the adjusted AUC to 0·706 (95% CI, 0·648-0·750). Interpretation: The identified fecal microbial signature could complement the diagnostic capacity of FIT for detecting advanced adenomas. Funding Statement: This work was supported by the CAMS Innovation Fund for Medical Sciences (2017-I2M-1-006, 2019-I2M-2-002), the National Natural Science Foundation of China (81703309). Beijing Nova Program of Science and Technology (Z191100001119065), and Natural Science Foundation of Beijing Municipality (7202169). Declaration of Interests: The authors declare no potential conflicts of interest. Ethics Approval Statement: This study was approved by the Ethics Committee of the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College (18-013/1615).

PD-10 Improvement of Asia-Pacific colorectal screening score combined with fecal immunochemical testing at adjusted thresholds in colorectal cancer screening

The Asia-Pacific colorectal screening (APCS) score was developed in identifying the potential high-risk population of colorectal cancer (CRC). However, the clinical utility of such a risk score has not been fully elucidated. We aimed to evaluate the diagnostic accuracy and cost to detect one advanced neoplasia (AN) of the APCS score combined with fecal immunochemical testing (FIT) at various scenarios versus FIT alone in detecting AN.

Improvement of Asia-Pacific colorectal screening score and evaluation of its use combined with fecal immunochemical test

BackgroundThe Asia-Pacific Colorectal Screening (APCS) score is effective to screen high-risk groups of advanced colorectal neoplasia (ACN) patients but needs revising and can be combined with the fecal immunochemical test (FIT). This paper aimed to improve the APCS score and evaluate its use with the FIT in stratifying the risk of ACN.MethodsThis prospective and multicenter study enrolled 955 and 1201 asymptomatic Chinese participants to form the derivation and validation set, respectively. Participants received the risk factor questionnaire, colonoscopy and FIT. Multiple logistic regression was applied, and C-statistic, sensitivity and negative predictive values (NPVs) were used to compare the screening efficiency.ResultsA modified model was developed incorporating age, body mass index (BMI), family history, diabetes, smoking and drinking as risk factors, stratifying subjects into average risk (AR) or high risk (HR). In the validation set, the HR tier group had a 3.4-fold (95% CI 1.8–6.4) increased risk for ACN. The C-statistic for the modified score was 0.69 ± 0.04, and 0.67 ± 0.04 for the original score. The sensitivity of the modified APCS score combined with FIT for screening ACN high-risk cohorts was 76.7% compared with 36.7% of FIT alone and 70.0% of the modified APCS score alone. The NPVs of the modified score combined with FIT for ACN were 98.0% compared with 97.0% of FIT alone and 97.9% of the modified APCS score alone.ConclusionsThe modified score and its use with the FIT are efficient in selecting the HR group from a Chinese asymptomatic population.

Comparative evaluation of colonoscopy, fecal immunochemical test, and a novel risk-adapted approach for colorectal cancer screening: preliminary baseline results of a multicentre randomised controlled trial (Target-C)

BackgroundFor colorectal cancer (CRC) screening, the use of risk prediction models to identify potential high-risk populations and implementation of appropriate risk-adapted screening may be more cost-effective than traditional screening strategies. However, evidence from randomised controlled trials is lacking. This study aimed to evaluate colonoscopy, fecal immunochemical test (FIT) and a novel risk-adapted screening approach in a large-scale multicentre randomised controlled trial in China. MethodsThis ongoing trial has been conducted in six study centres in five provinces in China since May 2018. People aged 50–74 years living in the study areas were approached to assess eligibility. Overall, 19 582 eligible participants were enrolled from May, 2018, to May, 2019. After providing signed informed consent, participants were randomly assigned to one of three screening groups, with a 1:2:2 ratio: (1) one-time colonoscopy (n=3937); (2) annual fecal immunochemical test (FIT; n=7858); and (3) annual risk-adapted screening strategy (n=7787). The risk-adapted screening strategy used an established CRC risk scoring system, the Asia-Pacific Colorectal Screening Score. Participants at high risk of CRC were referred for colonoscopy, whereas participants at low risk of CRC were referred for a FIT. Participants with positive FIT results were also referred for diagnostic colonoscopy. Information on clinical reports and epidemiological risk factors were collected and stored in a web-based data system. The primary outcome was detection rate of advanced colorectal neoplasia and secondary outcomes included rate of adherence to the study protocol, compliance rate of colonoscopy, detection rate of any neoplasm, complication rate, and the rate of mortality. A 4-year screening phase (with 1-year baseline screening and 3 years of follow-up screening) will be conducted for all participants and a subsequent 6-year active and passive follow-up phase will be implemented. Here we present the preliminary baseline screening results. This study was approved by the Ethics Committee of the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College (18-013/1615) and the protocol was registered in the Chinese Clinical Trial Registry (identifier: ChiCTR1800015506). FindingsAfter we excluded 36 participants who did not meet the inclusion criteria after further evaluation, 19 546 participants were included for the primary analysis (3916 colonoscopy, 7854 FIT, and 7776 risk-adapted screening). Mean age was 60·5 (SD 6·5) years and 41·7% (8154 of 19 546) were men. No statistically significant differences for age and sex distribution were observed between the groups. Participation rates were 42·5% (1665 of 3916) for colonoscopy, 94·0% (7386 of 7854) for FIT, and 85·2% (6628 of 7776) for risk-adapted screening. Of the participants assessed to be at high risk of CRC in the risk-adapted group (18·9%, 1472 of 7776), 49·2% (724 of 1472) accepted colonoscopy screening, a significantly higher proportion than in the colonoscopy group (42·5%; p<0·05). Of participants assessed to be at low risk of CRC in the risk-adapted screening group (80·7%, 6279 of 7776), 94·0% (5904 of 6279) accepted FIT screening, similar to the rate in the FIT group (94·0%). The overall positivity rate of FIT was 14·3%, and over 85% of participants with positive FIT results undertook subsequent diagnostic colonoscopy. For the intention-to-screen analysis, detection rates for advanced colorectal neoplasms were 2·93% for colonoscopy, 1·29% for FIT and 1·83% for risk-adapted screening. The FIT and the risk-adapted screening groups had lower numbers of colonoscopies needed to detect one advanced neoplasm than the colonoscopy group (eight, ten, and 15 colonoscopies, respectively). InterpretationThis is the first large-scale population-based trial in China to compare effectiveness of three different colorectal cancer screening strategies targeting adults aged 50–74 years. For the interim analysis of the baseline screening in this trial, the FIT and the novel risk-adapted screening approach had higher participation rates than the colonoscopy screening approach, and they required fewer numbers of colonoscopies to detect one advanced neoplasm, indicating the feasibility and effectiveness of these two approaches in population-based CRC screening. The findings of this study may provide timely evidence in designing effective population-based CRC screening strategies. FundingThis study was sponsored by Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (2017-I2M-1-006) and the National Natural Science Foundation of China (81703309).

Validation of Asia-Pacific Colorectal Screening Score for Asymptomatic Participants and Outpatients in Northwest District of China

Introduction: Asia-Pacific Colorectal Screening (APCS) score has been implemented for colorectal cancer screening in asymptomatic cohort in many regions. However, no study has validated its efficiency in Asian outpatients with mild-self-limited gastrointestinal symptoms yet. The purpose of this study was to validate its efficiency in asymptomatic subjects and outpatients in Ningxia. Methods: The records of 329 asymptomatic participants and 300 outpatients were collected and analyzed from database in the General Hospital of Ningxia Medical University from September 2017 to April 2018. These 2 main groups were divided into 3 tiers based on the scores calculated by the category of APCS score. The detection rates of advanced colorectal neoplasia (ACRN) were further compared according to histopathological classifications of tissues acquired during colonoscopy. Results: Among the 329 participants screened in the asymptomatic cohort, 78 subjects (23.7%) were in the low-risk (LR) tier, 187 subjects (56.8%) in the moderate-risk (MR) tier, and 64 subjects (19.5%) in the high-risk (HR) tier. The percentage of ACRN in the LR, MR, and HR groups was 1.3, 8.6, and 20.3%, respectively. In the 300 outpatient cohorts, 78 patients (26%) were in the LR tier, 140 patients (46.7%) in the MR tier, and 82 patients (27.3%) in the HR tier. The detection rates of ACRN in the LR, MR, and HR groups were 0, 10, and 39%, respectively. Conclusion: APCS score is an effective method for ACRN screening in asymptomatic and also the outpatient subjects. Individuals with HR scores should be given priority for colonoscopy.

Prospective assessment of the risk for colorectal neoplasia in a Mexican population according to risk categories.

e15158 Background: General population screening can reduce colorectal cancer (CRC) mortality. International guidelines recommend CRC screening for asymptomatic people over 50 years. There is no established national screening program in Mexico. Even in countries with low incidence of CRC such as Mexico, targeted screening of subjects at high risk could decrease resource utilization and cost. Our aim was to describe the distribution among an average-risk population based on risk for colorectal neoplasia (CRN). Methods: We performed a prospective assessment of the risk for CRN among asymptomatic people over 50 years at Instituto Nacional de Ciencias Médicas y Nutrición between 2017-2018. The inclusion was competitive consistent with our age-sex pyramid. We included workers, non-family attendants and patients (internal medicine consultation). Each subject answered a standardized questionnaire, which included information on their age, gender, family history of CRC, diabetes, body mass index (BMI), smoking status and drinking habits. In order to stratify the population according to their risk for CRN, we used the Asia-Pacific Colorectal Screening (APCS) score. Results: We included 256 subjects. Median age was 59 y/o (50-93), 52% were female. 5% had a first-degree relative with CRC. 44% were current or ex-smoker and 9% reported alcohol consumption. 21% had diabetes. The median BMI was 27.3 (17-51). According to the APCS score, 60% were assigned as average risk (AR) and 40% as high risk (HR) for CRN. We observed a higher proportion of HR compared to our previous retrospective data (Table). Conclusions: We prospectively confirmed that using basic clinical information (age, gender, smoking status, family history of CRC, BMI and diabetes), it is possible to identify a subset of asymptomatic subjects at high risk for CRN in whom screening strategies should be prioritized. In developing countries with limited resources, a focus on high risk groups could improve cost effectiveness of screening colonoscopy. Risk stratification based on APCS score. [Table: see text]