Validation of the Asia Pacific Colorectal Screening (APCS) score in a Western population: An alternative screening tool

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

BACKGROUND AND AIM

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).

METHODS

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.

RESULTS

From the 101 records screened, 13 eligible studies in the Asia-Pacific region involving 69 762 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.

CONCLUSIONS

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.

Establishment and validation of symptomatic patients colorectal screening score for predicting colorectal neoplasia risk

OBJECTIVES

Currently, most colorectal neoplasia (CRN) screening strategies target asymptomatic individuals. However, studies on patients with non-specific gastrointestinal symptoms (NSGS) are limited. We aimed to develop a CRN risk score specifically for patients with NSGS.

METHODS

We prospectively enrolled patients who underwent initial colonoscopy between June 2020 and June 2021. A new risk scoring system was constructed and its applicability was evaluated.

RESULTS

A total of 1522 consecutive patients were enrolled, among whom 1016 symptomatic patients were randomly divided into a training cohort and a validation cohort at a ratio of 7:3. The constructed Symptomatic Patients Colorectal Screening (SPCS) score showed higher diagnostic efficacy and sensitivity than several previous scoring systems. Using the SPCS score, the patients were divided into a low-risk group (-2 to 3 points) and a high-risk group (4-10 points) for CRN. Additionally, the detection rate of CRN in the training and validation cohorts of the high-risk group were 41.7% and 37.0%, respectively. The SPCS score detected 79.3% (188/237) of CRN and 87.5% (42/48) of advanced CRN in the high-risk group, which reduced the workload of colonoscopy to 45.9% (466/1016).

CONCLUSION

An effective CRN risk scoring system was established and validated for symptomatic patients, which accurately classified individuals into low-risk and high-risk groups for CRN and might be used to optimize colonoscopic resource allocation.

Third Asia-Pacific consensus recommendations on colorectal cancer screening and postpolypectomy surveillance

The Asia-Pacific region has the largest number of cases of colorectal cancer (CRC) and one of the highest levels of mortality due to this condition in the world. Since the publishing of two consensus recommendations in 2008 and 2015, significant advancements have been made in our knowledge of epidemiology, pathology and the natural history of the adenoma-carcinoma progression. Based on the most updated epidemiological and clinical studies in this region, considering literature from international studies, and adopting the modified Delphi process, the Asia-Pacific Working Group on Colorectal Cancer Screening has updated and revised their recommendations on (1) screening methods and preferred strategies; (2) age for starting and terminating screening for CRC; (3) screening for individuals with a family history of CRC or advanced adenoma; (4) surveillance for those with adenomas; (5) screening and surveillance for sessile serrated lesions and (6) quality assurance of screening programmes. Thirteen countries/regions in the Asia-Pacific region were represented in this exercise. International advisors from North America and Europe were invited to participate.

A scoping review of risk-stratified bowel screening: current evidence, future directions

PURPOSE

In this scoping review, we examined the international literature on risk-stratified bowel screening to develop recommendations for future research, practice and policy.

METHODS

Six electronic databases were searched from inception to 18 October 2021: Medline, Embase, PsycINFO, CINAHL, Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials. Forward and backwards citation searches were also undertaken. All relevant literature were included.

RESULTS

After de-deduplication, 3,629 records remained. 3,416 were excluded at the title/abstract screening stage. A further 111 were excluded at full-text screening stage. In total, 102 unique studies were included. Results showed that risk-stratified bowel screening programmes can potentially improve diagnostic performance, but there is a lack of information on longer-term outcomes. Risk models do appear to show promise in refining existing risk stratification guidelines but most were not externally validated and less than half achieved good discriminatory power. Risk assessment tools in primary care have the potential for high levels of acceptability and uptake, and therefore, could form an important component of future risk-stratified bowel screening programmes, but sometimes the screening recommendations were not adhered to by the patient or healthcare provider. The review identified important knowledge gaps, most notably in the area of organisation of screening services due to few pilots, and what risk stratification might mean for inequalities.

CONCLUSION

We recommend that future research focuses on what organisational challenges risk-stratified bowel screening may face and a consideration of inequalities in any changes to organised bowel screening programmes.

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

OBJECTIVES

This 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.

METHODS

Our 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.

RESULTS

In 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.

CONCLUSIONS

Our 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.

Colorectal screening using the immunochemical faecal occult blood test kit among the Malaysian cohort participants

BACKGROUND

There has been a rapid increase in colorectal cancer (CRC) cases in Asian countries, including Malaysia. CRC is usually diagnosed at a late stage, and early detection of CRC is vital in improving survival. This study was conducted to determine the uptake rate of the immunochemical faecal occult blood test (iFOBT), the response rate to colonoscopy, and the CRC detection rate. We also wanted to identify the association between colorectal neoplasia and the Asia Pacific Colorectal Cancer Screening (APCS) scoring system.

METHODS

We recruited 2264 individuals from The Malaysian Cohort participants aged 35-65 years who consented to colorectal screening using the iFOBT kit from July 2017 until January 2019.

RESULTS

The response rate and positive iFOBT test rate of this study were 79.6% and 13.1% respectively. Among those with positive results, 125 individuals (52.7%) underwent colonoscopy; CRC was detected in six of them while 45 others (36.0%) had polyps. The overall CRC detection rate was 0.3% while the colorectal neoplasia detection rate (both colorectal cancer and colorectal polyps) was 2.3%. The APCS scoring indicated a significant association with colorectal neoplasia risk, with increasing trend by severity from moderate to high risk (3.46-11.14) compared to low risk. Most of the participants who were positive for iFOBT were those at high risk.

CONCLUSIONS

The awareness of CRC risk and iFOBT screening are important strategies for early detection of CRC. We showed a CRC detection rate of 0.3 % among those who volunteered to have the iFOBT screening.

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

Background

The 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.

Methods

This 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.

Results

A 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.

Conclusions

The modified score and its use with the FIT are efficient in selecting the HR group from a Chinese asymptomatic population.

A healthy lifestyle pattern has a protective association with colorectal polyps

BACKGROUND

Colorectal cancer is associated with lifestyle characteristics such as diet, physical inactivity, obesity, and smoking, but these are not incorporated in screening recommendations. Moreover, the joint association of these factors with various colorectal polyps is not established.

METHODS

A case-control study, among consecutive subjects aged 40-70 years, undergoing colonoscopy. Cases with colorectal polyps were compared with controls. Detailed information was gathered regarding polyp histology and anatomic location, demographics, medical history, anthropometrics, and lifestyle. The healthy lifestyle index was estimated as the sum of: non-smoking, maintaining a healthy weight, healthy diet, and physical activity.

RESULTS

A total of 788 participants were included (cases n = 403, controls n = 385). The healthy lifestyle index had a negative association with colorectal polyps (OR = 0.72, 95% CI 0.62-0.85, P < 0.001), both adenomas and serrated polyps (OR = 0.75, 0.64-0.89, and OR = 0.59, 0.44-0.79, respectively), and both proximal and distal adenomas (OR = 0.77, 0.62-0.95, and OR = 0.73, 0.59-0.90, respectively). Adherence to ≥ 2 healthy lifestyle components was strongly related with colorectal polyps (OR = 0.50, 0.34-0.75, P = 0.001). Abstinence from smoking, and a healthy diet were the factors most strongly associated with lower odds of colorectal polyps (OR = 0.58, 0.42-0.79, and OR = 0.61, 0.44-0.85, respectively).

CONCLUSIONS

Adherence to a healthy lifestyle (≥2 healthy lifestyle components) is inversely associated with colorectal polyps, especially serrated and distal polyps, with no dose-response association. Components most strongly associated with lower odds of colorectal polyps were maintaining a healthy diet and abstinence from smoking. Lifestyle-related characteristics may assist in risk stratification and are potential goals for colorectal neoplasia prevention.

Overweight as an Additional Risk Factor for Colorectal Neoplasia in Lean Population

Background:

Overweight in Thailand is not as common as in Western countries. We sought to evaluate overweight as the additional risk factor that can increase the prediction of colorectal neoplasia (CRN) detection in Thais apart from the Asia-Pacific Colorectal Screening (APCS) score.

Methods:

We prospectively enrolled asymptomatic 338 subjects who underwent screening colonoscopy between November 2016 and September 2017. All risk factors according to APCS, BMI and the presence of metabolic syndrome were collected. Overweight was defined as BMI ≥23 kg/m². By APCS score, subjects were categorized into 1) high-risk and 2) average-risk. Using the combination of APCS score and overweight, subjects were stratified into 4 groups; high-risk with overweight (G1), average-risk with overweight (G2), high-risk with normal weight (G3) average-risk and with normal weight (G4). Logistic regression analysis was used to estimate the risk of detecting CRN.

Results:

The prevalence of CRN in the high-risk subjects was higher than that of in the average-risk subjects (49%vs.32%; OR, 2.00; 95%CI, 1.17-3.41). After adjustment for APCS risk factors and metabolic syndrome, overweight significantly increased the risk of detecting CRN (OR, 2.52; 95%CI, 1.57-4.05). Among the 4 groups, the detection rates of CRN were significantly different (G1=64%, G2=40%, G3=32% and G4=21%, p<0.01). The relative risk of detecting CRN increased when G1 (OR 6.49; 95%CI, 2.87-14.67), and G2 (2.42; 1.39-4.21) were compared with G4.

Conclusions:

In addition to the APCS score, overweight is an independent risk factor for detecting CRN. In Thai population, combining overweight and APCS score may be useful to improve the prediction for CRN.

The performance of a community-based colorectal cancer screening program: Evidence from Shanghai Pudong New Area, China

Despite the rising disease burden of colorectal cancer (CRC), CRC screening has not yet been widely introduced as a large organized program in developing countries. To facilitate better delivery of screening in these areas, we investigated the performance of a large community-based CRC screening program implemented in Shanghai Pudong New Area during the period 2013-2016. We conducted a prospective cohort study by following up the screening behavior and results of tested participants in the program. Data from the program reporting system and monthly progress reports were collected. We used standard measures and indicators with modifications to evaluate the performance of the program. Disparities in CRC screening by age categories, primary screening results, and geographic areas were examined. A total of 403,098 individuals participated in the program, 25,764 of them were further screened by diagnostic colonoscopy (COL), and 505 people were eventually diagnosed with CRC as a result of the program. The program produced the following rates: participation (35.18%), primary screening positivity (24.89%), positive primary screening follow-up (26.26%), diagnostic COL (6.37%), and cancer detection (1.25‰). Vast variations in the quality of the program were observed across areas with different socioeconomic environments. The experience and lessons from the program suggest that incorporating the screening with other public health campaigns, using better-developed risk assessment tools, and allowing individual screening decisions for those aged above the target are possible practical ways to promote a better delivery of organized CRC screening programs.

Smoking Habits are Strongly Associated With Colorectal Polyps in a Population-based Case-control Study

GOALS

The goal of this study is to test the association between lifetime smoking habits and colorectal polyps of different classifications.

BACKGROUND

Smoking is an established risk factor for several cancers, including colorectal cancer. However, the association between lifetime smoking habits including intensity, duration, and cessation, and premalignant colorectal polyps is yet to be established.

STUDY

A case-control study among 828 consecutive subjects aged 40 to 70 years, undergoing screening or diagnostic colonoscopy. Exclusion criteria were: medically treated diabetes, colectomy, and belonging to colorectal cancer high risk group. Polyps were stratified according to histology (serrated or adenomatous polyp) and location. All participants underwent anthropometric measurements and a structured medical and lifestyle interview.

RESULTS

Current-smoking was more strongly associated with increased odds for distal rather than proximal polyps [odds ratio (OR), 4.00; 95% confidence interval (CI), 2.40-6.68 and OR, 2.52; 95% CI, 1.46-4.36, respectively], with serrated-polyps rather than adenomas (OR, 6.36; 95% CI, 2.77-14.57 and OR, 3.01; 1.90-4.74, respectively). All levels of smoking intensity (daily cigarettes) were associated with colorectal polyps. A dose-response association was seen between smoking duration and colorectal polyps. Smoking duration of ≥20 years was strongly associated with distal polyps (OR, 4.01; 95% CI, 1.62-9.84), independently of potential confounders, smoking intensity and years since smoking cessation. All associations were stronger for distal serrated polyps.

CONCLUSIONS

Smoking duration is associated with colorectal plyps, independently of other potential confounders, smoking intensity, and cessation. The association is stronger with distal rather than proximal polyps, and with serrated polyps rather than adenomas.

Asia-Pacific Colorectal Screening score: A useful tool to stratify risk for colorectal advanced neoplasms in Vietnamese patients with irritable bowel syndrome

BACKGROUND AND AIM

The Asia-Pacific Colorectal Screening (APCS) score has been validated in several populations but not yet in patients with irritable bowel syndrome (IBS). The aim of this study was to assess the performance of APCS score in stratifying risk of colorectal advanced neoplasms (CAN) in Vietnamese IBS patients.

METHODS

Consecutive patients who fulfilled IBS diagnosis criteria according to the Rome III were prospectively enrolled and underwent colonoscopy. APCS score for each patient was calculated by summing the points attributed by risk factors. Three tiers of risk were defined: 0-1 "average risk" (AR); 2-3 "moderate risk" (MR); and 4-7 "high risk" (HR). Logistic regression analysis was performed to assess the relative risk of CAN in HR group and MR group compared with AR group.

RESULTS

There were 404 patients with excellent bowel preparation and complete colonoscopy. The mean age was 48.8 ± 11.2 years and male : female ratio was 1.2:1. Twenty-eight patients (6.9%) were diagnosed with CAN: 19 (4.7%) advanced adenoma and 9 (2.2%) invasive colorectal cancer. Patients in the MR and HR tiers had 5.6-fold (95% confidence interval 1.2 to 24.7, P = 0.012) and 12.1-fold (95% confidence interval 2.6 to 56.2, P < 0.001) increased rates of CAN compared with those in the AR tier, respectively. Three out of 9 patients with invasive colorectal cancer had no alarm features but had high sum APCS score (2 in MR tier and 1 in HR tier).

CONCLUSION

The APCS score is useful to identify IBS patients with high risk of CAN for colonoscopy priority.

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.

Impact of Fecal Hb Levels on Advanced Neoplasia Detection and the Diagnostic Miss Rate For Colorectal Cancer Screening in High-Risk vs. Average-Risk Subjects: a Multi-Center Study

Objectives:

The Asia-Pacific Colorectal Screening (APCS) scoring system was developed to identify high-risk subjects for advanced neoplasia. However, the appropriate fecal immunochemical test (FIT) cutoff for high-risk population may be different from that of average-risk population. We aimed to evaluate the FIT performance at different cutoffs in high-risk subjects undergoing colorectal cancer (CRC) screening.

Methods:

We prospectively enrolled asymptomatic subjects aged 50–75 years. Using the APCS score, subjects were stratified into either the average-risk or high-risk groups. All subjects were tested with one-time quantitative FIT and underwent colonoscopy. We compared the FIT performance for advanced neoplasia between two groups using different cutoffs (5 (FIT5), 10 (FIT10), 20 (FIT20), 30 (FIT30), and 40 (FIT40) μg Hb/g feces).

Results:

Overall, 1,713 subjects were recruited, and 1,222 (71.3%) and 491 (28.7%) were classified as average-risk and high-risk, respectively. Advanced neoplasia was detected in 90 (7.4%) of the average-risk subjects and 65 (13.2%) of the high-risk subjects. In the high-risk group, by decreasing the cutoff from FIT40 to FIT5, the sensitivity increased by 33.8 percentage points with decreased specificity by 11 percentage points. In the average-risk group, the sensitivity increased by 20 percentage points with decreased specificity by 9.6 percentage points. At the lowest cutoff (FIT5), the number of needed colonoscopies to find one advanced neoplasia was 2.8 and 6.1 for the high-risk and average-risk groups, respectively.

Conclusions:

Using an appropriate FIT cutoff for CRC screening in high-risk subjects could improve CRC screening performance and reduce the unnecessary colonoscopies. To maintain high sensitivity and specificity for advanced neoplasia, the optimal cutoff FIT in the high-risk subjects should be lower than that in the average-risk subjects.

How significant is the association between metabolic syndrome and prevalence of colorectal neoplasia?

The incidence and prevalence of metabolic syndrome (MS) and colorectal cancer (CRC) has been rising in developed countries. The association between these two diseases has been widely studied and reported. Less evidence is available about the relationship between MS and CRC precancerous lesions (adenomatous polyps, adenomas). The aim of this paper is to present an overview of our scientific understanding of that topic and its implication in clinical practice. One of the principal goals of current CRC secondary prevention efforts is to detect and remove the precancerous lesions in individuals with an average CRC risk to prevent the development of invasive cancer. MS is not currently considered a high-risk CRC factor and is therefore not included in the guidelines of organized screening programs. However, in light of growing scientific evidence, the approach to patients with MS should be changed. Metabolic risk factors for the development of adenomas and cancers are the same - obesity, impaired glucose tolerance, dyslipidemia, hypertension, cardiovascular diseases and diabetes mellitus type 2. Therefore, the key issue in the near future is the development of a simple scoring system, easy to use in clinical practice, which would identify individuals with high metabolic risk of colorectal neoplasia and would be used for individual CRC secondary prevention strategies. Currently, such scoring systems have been published based on Asian (Asia-Pacific Colorectal Screening Score; APCS) and Polish populations.