Performance of a colorectal cancer screening protocol in an economically and medically underserved population

Performance of DNA methylation and blood-borne tumor indicators in detecting colorectal neoplasia and adenomas: a comparative study with the fecal occult blood test

Objectives

To evaluate the performance of stool methylated syndecan2 (mSDC2), methylated septin9 (mSEPT9), fecal occult blood test (FOBT), carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125) and carbohydrate antigen 199 (CA199) in detecting colorectal neoplasia and adenomas.

Methods

Blood-borne CEA, CA125, and CA199 levels were measured by electrochemiluminescence. The SDC2 methylation was detected by Methylation Detection Kit for Human SDC2 Gene (Real time PCR), and the SEPT9 methylation was detected by the Septin9 Gene Methylation Detection Kit based on PCR fluorescent probe assay. The colonoscopy combined with tissue biopsy pathology was used as a validation criterion for colorectal neoplasia.

Results

In detecting colorectal neoplasia, the AUCs of mSDC2, FOBT and mSEPT9 were 0.935 (95% CI: 0.915-0.956, P<0.001), 0.824 (95% CI: 0.617-1.000, P<0.001) and 0.671 (95% CI: 0.511-0.831, P<0.001), respectively. The sensitivity of mSDC2, FOBT and mSEPT9 were 100.0%, 66.7% and 40.0%, respectively. But the AUC of CEA, CA125 and CA199 were not statistically significant for colorectal neoplasia (all P>0.05). The combined application of mSEPT9 and mSDC2 showed the best predictive performance (AUC: 0.956, 95% CI: 0.887~1.000). For adenomas, the AUC of FOBT was extremely low (AUC: 0.524, 95% CI: 0.502-0.545, P=0.004). The CEA, CA125, CA199, mSEPT9 and mSDC2 were not statistically significant in detecting adenomas (all P>0.05).

Conclusions

For individual tests, FOBT and mSDC2 are relatively better indicators for detecting colorectal neoplasia compared to mSEPT9, CEA, CA125 and CA199. The combined form of mSEPT9 and mSDC2 to detect colorectal neoplasia has good predictive performance. However, none of these indicators demonstrated significant predictive power for detecting adenomas in our study.

Combining FITs and HRFQ with colonoscopy improve the cost-effectiveness of a 9-year mass colorectal cancer screening program

BACKGROUND

Colorectal cancer (CRC) incidence has been increasing. Colonoscopy is still a gold standard method for its early diagnosis but using colonoscopy alone as a mass screening method is unrealistic. This study is to investigate whether combining fecal immunochemical test (FIT) and high-risk-factors questionnaire (HRFQ) with colonoscopy improve the cost-effectiveness of a mass CRC screening.

PATIENTS AND METHODS

CRC screening protocol combining FITs and HRFQ in the first stage and colonoscopy in the second stage was used in 50 villages/towns in 2007-2015. Residents aged 40-74 years were eligible for this free screening. A total of 160 210 (76.12%) participants completed first-stage screening, and 28 679 (17.90%) participants were defined as positive, among which 21 715 (75.72%) participants completed colonoscopy and were included in the final analysis. Outcomes were followed up until 2020.

RESULTS

The compliance was 76.12% and 75.72% in the first and second screening stage, respectively. A total of 252 CRC, 4033 adenoma, 1234 advanced neoplasm, and 5534 total neoplasm cases were detected in the screening. The positive predictive values of CRC, adenoma, advanced neoplasm, and total neoplasm were higher in FITs+ than those in the HRFQ+ population, respectively. A total of 64.60% and 43.42% total neoplasm cases were found in FITs+ and HRFQ+ (8.02% for both), respectively. The total colorectal neoplasm and CRC cases detected by combining HRFQ and FITs increased by 55.08% and 40.00%, respectively, and their increases were higher compared to HRFQ. The detection cost per any neoplasm by combining HRFQ and FITs was <$5331, while that by FITs and HRFQ alone was <$4570 and $5380, respectively.

CONCLUSIONS

Combining FITs and HRFQ with colonoscopy improve the cost-effectiveness of a mass CRC screening program. This protocol can be recommended for most populations, especially those in the countries and areas with high population density and low physician/population ratio.

A risk-prediction score about colorectal lesions based on the Chinese population of high-risk participants aged 50-65 years

OBJECTIVES

The present study aims to develop an effective risk-prediction score (RPS) to improve screening efficiency and contribute to secondary prevention of colorectal cancer (CRC).

STUDY DESIGN

Screening for colorectal lesions.

METHODS

14,398 high-risk individuals aged 50-65 years were included. The baseline characteristics of participants with and without colorectal lesions (CL) were compared using a Chi-squared test. The overall population was randomly split into a training set and a test set in the ratio of 80% and 20%. One-factor and multifactor logistic regression analyses were performed in the training set to construct the RPS (scores of 0-9.62). Area under curve (AUC) was calculated as an estimate of predictive performance using the receiver-operating characteristic (ROC) curve in the test set.

RESULTS

In the study population, being male, advanced age, current or previous smoking, weekly alcohol consumption, high body mass index (BMI ≥24 kg/m2), and previously detected colonic polyp were associated with higher risk of CL. Compared to the low-risk group (0-2.31 points), the ORs and 95% confidence intervals (CIs) for the moderate-risk group (2.31-3.85 points) and high-risk group (3.85-8.42 points) were 1.58 (1.44, 1.73) and 2.52 (2.30, 2.76), respectively. For every 1-point increase in score, participants had a 27% increased risk of CL (OR:1.27, 95% CI: 1.24, 1.30). For participants with CL predicted by RPS, the area under the working characteristic curve was 0.61 (P < 0.001).

CONCLUSION

Our RPS can quickly and efficiently identify multiple lesions of the colorectum. Combining RPS with existing screening strategies facilitates the identification of very high-risk individuals and may help to prevent CRC.

Trends in colorectal cancer screening compliance and incidence among 60- to 74-year-olds in China

BACKGROUND

Compliance with colonoscopy among elderly individuals participating in colorectal cancer (CRC) screening programs is unsatisfactory, despite a high detection rate of bowel-related diseases. In this study, our aim was to analyze the impact of risk factors on the trends of compliance and detection rates in colonoscopy among high-risk individuals aged 60-74.

METHODS

A retrospective study was conducted on the high-risk individuals aged 60-74 participating in the 2021 CRC screening program in Tianjin, China. Logistic regression analyses, including both univariate and multivariate analyses, were performed to explore the impact of different risk factors on colonoscopy compliance among the high-risk individuals. Besides, the study investigated the influence of various risk factors on the detection rates of bowel-related diseases among the high-risk individuals who underwent colonoscopy.

RESULTS

A total of 24,064 high-risk individuals were included, and 5478 individuals received a free colonoscopy, with an overall compliance of 22.76%. Among them, the adenoma detection rate was 55.46%. Males and individuals with a positive FIT had high compliance and detection rates for CRC, advanced adenomas (AA), advanced colorectal neoplasia (ACN), and colorectal neoplasm (CN). Individuals aged 70-74 were associated with low compliance but high CRC, ACN, and CN detection rates. Individuals who reported a history of chronic constipation, bloody mucous, and CRC in first-degree relative showed high compliance but no significantwere associated with the detection rates of CRC, AA, and CN.

CONCLUSION

This study reported several risk factors associated with the screening behaviors for CRC. Patterns and trends in CRC, AA, ACN, and CN compliance and detection rates correlate with risk factors.

Combining fecal immunochemical testing and questionnaire-based risk assessment in selecting participants for colonoscopy screening in the Chinese National Colorectal Cancer Screening Programs: A population-based cohort study

BACKGROUND

Screening reduces colorectal cancer (CRC) burden by allowing early resection of precancerous and cancerous lesions. An adequate selection of high-risk individuals and a high uptake rate for colonoscopy screening are critical to identifying people more likely to benefit from screening and allocating healthcare resources properly. We evaluated whether combining a questionnaire-based interview for risk factors with fecal immunochemical test (FIT) outcomes for high-risk assessment is more efficient and economical than a questionnaire-based interview-only strategy.

METHODS AND FINDINGS

In this multicenter, population-based, prospective cohort study, we enrolled community residents aged 40 to 74 years in 29 provinces across China. From 2016 to 2020, a total of 1,526,824 eligible participants were consecutively enrolled in the Cancer Screening Program in Urban China (CanSPUC) cohort, and 940,605 were enrolled in the Whole Life Cycle of Cancer Screening Program (WHOLE) cohort, with follow-up to December 31, 2022. The mean ages were 56.89 and 58.61 years in CanSPUC and WHOLE, respectively. In the WHOLE cohort, high-risk individuals were identified by combining questionnaire-based interviews to collect data on risk factors (demographics, diet history, family history of CRC, etc.) with FIT outcomes (RF-FIT strategy), whereas in the CanSPUC cohort, high-risk individuals were identified using only interview-based data on risk factors (RF strategy). The primary outcomes were participation rate and yield (detection rate of advanced neoplasm, early-stage detection rate of CRCs [stage I/II], screening yield per 10,000 invitees), which were reported for the entire population and for different gender and age groups. The secondary outcome was the cost per case detected. In total, 71,967 (7.65%) and 281,985 (18.47%) individuals were identified as high-risk and were invited to undergo colonoscopy in the RF-FIT group and RF group, respectively. The colonoscopy participation rate in the RF-FIT group was 26.50% (19,071 of 71,967) and in the RF group was 19.54% (55,106 of 281,985; chi-squared test, p < 0.001). A total of 102 (0.53%) CRCs and 2,074 (10.88%) advanced adenomas were detected by the RF-FIT, versus 90 (0.16%) and 3,593 (6.52%) by the RF strategy (chi-squared test, both p < 0.001). The early-stage detection rate using the RF-FIT strategy was significantly higher than that by the RF strategy (67.05% versus 47.95%, Fisher's exact test, p = 0.016). The cost per CRC detected was $24,849 by the RF-FIT strategy versus $55,846 by the RF strategy. A limitation of the study was lack of balance between groups with regard to family history of CRC (3.5% versus 0.7%).

CONCLUSIONS

Colonoscopy participation and screening yield were better with the RF-FIT strategy. The association with CRC incidence and mortality reduction should be evaluated after long-term follow-up.

Age- and sex-stratified detection rates and associated factors of colorectal neoplasia in the Tianjin colorectal cancer screening program from 2012 to 2020

PURPOSE

Colorectal cancer (CRC) screening has been implemented in Tianjin, China since 2012. The objective was to estimate the neoplasia detection rate in a high-risk population by age and sex and to investigate the potential factors associated with colorectal neoplasia.

PATIENTS AND METHODS

This study is based on data of the Tianjin CRC screening program from 2012 to 2020. Residents with a positive high-risk factors questionnaire (HRFQ) or a positive faecal immunochemical test (FIT) were identified as high-risk participants and were subsequently recommended for a free colonoscopy.

RESULTS

A total of 4,117,897 eligible participants aged 40-74 years completed both a HRFQ and FIT, and 217,164 (5.3%) of them were identified as high-risk participants. Positive rates of preliminary screening increased with age and were higher in females than in males. For 57,971 participants undertaking colonoscopy, the detection rates of nonadvanced adenoma, advanced adenoma and CRC were 37.8%, 5.7% and 1.6%, respectively. Detection rates of advanced neoplasia increased from the age of 50 and were higher in males. For nonadvanced neoplasia, a strong increase was observed in males from the age of 40 and in females from the age of 50. Male sex had a greater impact on individuals aged 40-49 than on older individuals. Several factors including current smoking, drinking, and higher body mass index (BMI) were significantly associated with the presence of neoplasia, whereas, these associations were mainly restricted to individuals aged above 50 but not those aged 40-49 years.

CONCLUSIONS

These findings support that age-specific risk stratification and sex-specific initiating ages for CRC screening should be recommended to improve the accuracy and effectiveness of current screening strategy.

Diagnostic accuracy of risk assessment and fecal immunochemical test in colorectal cancer screening: Results from a population-based program and meta-analysis

BACKGROUND

Fecal immunochemical test (FIT) is a commonly used initial test for colorectal cancer (CRC) screening. Parallel use of FIT with risk assessment (RA) could improve the detection of non-bleeding lesions, but at the expense of compromising sensitivity. In this study, we evaluated the accuracy of FIT and/or RA in the Shanghai CRC screening program, and systematically reviewed the relevant evaluations worldwide.

METHODS

RA and 2-specimen FIT were used in parallel in the Shanghai screening program, followed by a colonoscopy among those with positive results. Sensitivity, specificity, detection rate of CRC, positive predictive value (PPV), and other measures with their 95% confident intervals were calculated for each type of tests and several assumed combined tests. We further searched PubMed, Embase, Web of Science, and Cochrane Library for relevant studies published in English up to January 5, 2022.

RESULTS

By the end of 2019, a total of 1,901,360 participants of the screening program completed 3,045,108 tests, with 1,901,360 first-time tests and 1,143,748 subsequent tests. Parallel use of RA and 2-specimen FIT achieved a sensitivity of 0.78 (0.77-0.80), a specificity of 0.78 (0.78-0.78), PPV of 0.89% (0.86-0.92), and a detection rate of 1.99 (1.93-2.05) for CRC per 1000 among participants enrolled in the first screening round, and performed similarly among those who participated for several times. A meta-analysis of 103 published observational studies demonstrated a higher sensitivity [0.76 (0.36, 0.94)] but a much lower specificity [0.59 (0.28, 0.85)] of parallel use of RA and FIT for detecting CRC in average-risk populations than in our subjects. One-specimen FIT, the most commonly used initial test, had a pooled specificity comparable to the Shanghai screening program (0.92 vs. 0.91), but a much higher pooled sensitivity (0.76 vs. 0.57).

CONCLUSION

Our results indicate the limitation of FIT only as an initial screening test for CRC in Chinese populations, and highlight the higher sensitivity of parallel use of RA and FIT. Attempts should be made to optimize RA to improve effectiveness of screening in the populations.

Clinical evaluation of a multitarget fecal immunochemical test-sDNA test for colorectal cancer screening in a high-risk population: a prospective, multicenter clinical study

Colorectal cancer (CRC) is a major malignancy threatening the health of people in China and screening could be effective for preventing the occurrence and reducing the mortality of CRC. We conducted a multicenter, prospective clinical study which recruited 4,245 high-risk CRC individuals defined as having positive risk-adapted scores or fecal immunochemical test (FIT) results, to evaluate the clinical performance of the multitarget fecal immunochemical and stool DNA (FIT-sDNA) test for CRC screening. Each participant was asked to provide a stool sample prior to bowel preparation, and FIT-sDNA test and FIT were performed independently of colonoscopy. We found that 186 (4.4%) were confirmed to have CRC, and 375 (8.8%) had advanced precancerous neoplasia among the high CRC risk individuals. The sensitivity of detecting CRC for FIT-sDNA test was 91.9% (95% CI, 86.8-95.3), compared with 62.4% (95% CI, 54.9-69.3) for FIT (P < 0.001). The sensitivity for detecting advanced precancerous neoplasia was 63.5% (95% CI, 58.3-68.3) for FIT-sDNA test, compared with 30.9% (95% CI, 26.3-35.6) for FIT (P < 0.001). Multitarget FIT-sDNA test detected more colorectal advanced neoplasia than FIT. Overall, these findings indicated that in areas with limited colonoscopy resources, FIT-sDNA test could be a promising further risk triaging modality to select patients for colonoscopy in CRC screening.

A risk scoring system for advanced colorectal neoplasia in high-risk participants to improve current colorectal cancer screening in Tianjin, China

Background

Given the limited effectiveness of the current Chinese colorectal cancer (CRC) screening procedure, adherence to colonoscopy remains low. We aim to develop and validate a scoring system based on individuals who were identified as having a high risk in initial CRC screening to achieve more efficient risk stratification and improve adherence to colonoscopy.

Methods

A total of 29,504 screening participants with positive High-Risk Factor Questionnaire (HRFQ) or faecal immunochemical test (FIT) who underwent colonoscopy in Tianjin from 2012–2020 were enrolled in this study. Binary regression analysis was used to evaluate the association between risk factors and advanced colorectal neoplasia. Internal validation was also used to assess the performance of the scoring system.

Results

Male sex, older age (age ≥ 50 years), high body mass index (BMI ≥ 28 kg/m2), current or past smoking and weekly alcohol intake were identified as risk factors for advanced colorectal neoplasm. The odds ratios (ORs) for significant variables were applied to construct the risk score ranging from 0–11: LR, low risk (score 0–3); MR, moderate risk (score 4–6); and HR, high risk (score 7–11). Compared with subjects with LR, those with MR and HR had ORs of 2.47 (95% confidence interval, 2.09–2.93) and 4.59 (95% confidence interval, 3.86–5.44), respectively. The scoring model showed an outstanding discriminatory capacity with a c-statistic of 0.64 (95% confidence interval, 0.63–0.65).

Conclusions

Our results showed that the established scoring system could identify very high-risk populations with colorectal neoplasia. Combining this risk score with current Chinese screening methods may improve the effectiveness of CRC screening and adherence to colonoscopy.

Colorectal Cancer Screening With High Risk-Factor Questionnaire and Fecal Immunochemical Tests Among 5, 947, 986 Asymptomatic Population: A Population-Based Study

Background

The recent uptrend in colorectal cancer (CRC) incidence in China is causing an increasingly overwhelming social burden. And its occurrence can be effectively reduced by sensitizing CRC screening for early diagnosis and treatment. However, a large number of people in China do not undergo screening due to multiple factors. To address this issue, since 2012, a CRC screening program has been initiated in Tianjin.

Methods

Residents aged 40-74 years were eligible for CRC screening. The first was to complete the high-risk factor questionnaire (HRFQ) and undergo fecal immunochemical test (FIT). Then those with a positive result in any of the two screening methods were recommended for a free colonoscopy.

Results

The detection rate of intestinal diseases increased with age, had a male predominance, and was higher in residents from central urban areas and those with primary school above education level. The sensitivity of predicting CRC after colonoscopy in the high-risk group was 76.02%; the specificity was 25.33%.A significant decrease in the detection rate of intestinal disease, CRC and advanced adenoma was observed from positive FIT, the high-risk group and positive HRFQ, 47.13%, 44.79%, 42.30%; 3.15%, 2.44%, 1.76%; 7.72%, 6.42%, 5.08%, in that order, while no inter-group difference was found for the detection of polyps. In addition, the different combinations of HRFQ and FIT can enroll more high-risk population than FIT or (and) HRFQ only, and thus detect more intestinal diseases (include CRC/AA/Polyp).

Conclusion

The superimposition of different screening method for HRFQ and FIT is an effective strategy for the detection of CRC, AA, and Polyp, compared to HRFQ or FIT alone. However, further improvements in screening and interventions are needed to promote colonoscopy compliance.

Factors associated with adherence to colonoscopy among individuals who were positive in the preliminary screening for colorectal neoplasms

OBJECTIVES

This study aimed to investigate the potential factors associated with adherence to colonoscopy among participants who were preliminarily screened positive in a community-based colorectal cancer screening program in China.

METHODS

This study analyzed data from 1219 out of 6971 community residents who were identified as positive cases by the well-validated high-risk factor questionnaire (HRFQ) or fecal immunochemical test (FIT) in the preliminary screening stage for colorectal neoplasms. Patients showing adherence to colonoscopy were defined as those who received positive results in a preliminary screening for colorectal neoplasms and later received a colonoscopy examination as required. The associations of social-demographic factors, lifestyle behaviors, history of diabetes, body mass index (BMI), and risk factors in the HRFQ with adherence to colonoscopy were evaluated using logistic regression models.

RESULTS

Among 1219 participants who preliminarily screened positive, the top five risk factors reported by the participants were chronic constipation (25.9%), hematochezia (23.5%), family history of CRC in first-degree relatives (22.1%), chronic diarrhea (21.8%), and history of polyps (16.6%). Around 14.2% of participants who preliminarily screened positive reported three or more risk factors, and the proportion was 26.2% among participants who were positive according to both HRFQ and FIT. Among all participants who were preliminarily screened positive, the multivariable results showed that those who were married (OR = 1.58, 95% CI: 1.12, 2.25, p = 0.01), had chronic diarrhea (OR = 1.34, 95% CI: 1.00, 1.78, p = 0.047), and had a positive FIT (OR = 1.60, 95% CI: 1.21, 2.10, p < 0.001 for patients who were negative according to HRFQ but positive according to FIT; OR = 2.12, 95% CI: 1.33, 2.78, p = 0.002 for patients who were positive for both HRFQ and FIT) were more likely to adhere to colonoscopy, while participants with a history of cancer (OR: 0.50, 95% CI: 0.31, 0.79, p = 0.003) were less likely to adhere to colonoscopy. The results among participants who were tested positive according to only HRFQ were similar to those among all participants who were tested positive according to HRFQ or FIT. However, among participants who were tested positive according to only FIT, we only found that those who were married (OR = 2.52, 95% CI: 1.08, 5.90, p = 0.033) had a higher odds of adhering to colonoscopy, while those with a history of diabetes (OR = 0.35, 95% CI: 0.13, 0.96, p = 0.042) were less likely to adhere to colonoscopy.

CONCLUSION

Our findings provide evidence supporting the development of tailored interventional strategies that aim to improve adherence to colonoscopy for individuals with a high risk of colorectal neoplasms. Both barriers and facilitators associated with adherence to colonoscopy should be considered in supportive systems and health policies. However, further well-designed prospective studies are warranted to confirm our findings.

Factors associated with positive predictive value of preliminary screening in a two-step screening strategy for colorectal neoplasms in China

BACKGROUND

The positive predictive value (PPV) of high risk factor questionnaire (HRFQ) plus fecal immunochemical test (FIT) as preliminary screening strategy for colorectal-related neoplasia is relatively low. We aim to explore independent factors associated with PPVs of HRFQ combined FIT for selecting high risk individuals for colonoscopy.

METHODS

A total of 6971 residents were enrolled in a community-based screening program. Participants who had positive results of HRFQ and/or FIT and subsequently received colonoscopy were involved. The associations of socio-demographic factors, lifestyle behaviors, and high risk factors of colorectal cancer with PPVs of HRFQ, FIT, and their combination were evaluated by multivariable logistic regression models.

RESULTS

Among 572 involved cases, 249 (43.5%) colorectal neoplasms were detected by colonoscopy, including 71 advanced adenoma (12.4%) and 9 colorectal cancer (CRC) (1.6%). The PPVs of preliminary screening were 43.5% for total colorectal neoplasms, 14.0% for advanced neoplasm, and 1.6% for CRC. Adding positive HRFQ to FIT could improve the PPV from 3.5 to 8.0% for detecting CRC. Preliminarily screened positive individuals who were males [adjusted odds ratio (AOR): 1.95, 95% CI 1.31, 2.90; p  < 0.001], elders (> 60 years) (AOR: 1.70, 95% CI 1.17, 2.46; p  = 0.005), or ex-/current smokers (AOR: 3.04, 95% CI 1.31, 7.09; p  = 0.10) had higher odds of PPVs of detecting colorectal neoplasms.

CONCLUSIONS

Combining HRFQ and FIT could largely improve PPVs for screening advanced neoplasm and CRC. Gender and age-specific FIT cut-off values as well as initiating ages for CRC screening might be recommended to improve the accuracy and effectiveness of current screening algorithm.

The implementation of colorectal cancer screening interventions in low-and middle-income countries: a scoping review

BACKGROUND

Low- and middle-income countries (LMICs) experienced increasing rates of colorectal cancer (CRC) incidence in the last decade and lower 5-year survival rates compared to high-income countries (HICs) where the implementation of screening and treatment services have advanced. This review scoped and mapped the literature regarding the content, implementation and uptake of CRC screening interventions as well as opportunities and challenges for the implementation of CRC screening interventions in LMICs.

METHODS

We systematically followed a five-step scoping review framework to identify and review relevant literature about CRC screening in LMICs, written in the English language before February 2020. We searched Medline, Embase, Web of Science and Google Scholar for studies targeting the general, asymptomatic, at-risk adult population. The TIDieR tool and an implementation checklist were used to extract data from empirical studies; and we extracted data-informed insights from policy reviews and commentaries.

RESULTS

CRC screening interventions (n = 24 studies) were implemented in nine middle-income countries. Population-based screening programmes (n = 11) as well as small-scale screening interventions (n = 13) utilised various recruitment strategies. Interventions that recruited participants face-to-face (alone or in combination with other recruitment strategies) (10/15), opportunistic clinic-based screening interventions (5/6) and educational interventions combined with screening (3/4), seemed to be the strategies that consistently achieved an uptake of > 65% in LMICs. FOBT/FIT and colonoscopy uptake ranged between 14 and 100%. The most commonly reported implementation indicator was 'uptake/reach'. There was an absence of detail regarding implementation indicators and there is a need to improve reporting practice in order to disseminate learning about how to implement programmes.

CONCLUSION

Opportunities and challenges for the implementation of CRC screening programmes were related to the reporting of CRC cases and screening, cost-effective screening methods, knowledge about CRC and screening, staff resources and training, infrastructure of the health care system, financial resources, public health campaigns, policy commitment from governments, patient navigation, planning of screening programmes and quality assurance.

Six years of colorectal cancer mortality surveillance in the screening population for a risk stratified screening program

OBJECTIVE

To evaluate the impact of a colorectal cancer (CRC) risk predicting system on CRC mortality rates.

METHOD

An organized population screening program targeted at all the subjects (n = 102,076) at age 40-74 in nine towns of Jiashan county, China was conducted from 2007 to 2012. All of the screening participants were first triaged into high-risk & low-risk groups by a questionnaire and two fecal immunuochemical tests, only the high-risk subjects were subject to colonocopy. The screening participants were surveyed death caused by CRC for a total of six years after the enrollment. The CRC mortality in subgroups of the screening population was analyzed.

RESULTS

A total of 82,184 (80.51 % of the targeted population) screening participants were identified. CRC death were recorded for 142 subjects (28.819 per 10⁵ person-years). The age-adjusted relative risk(RR) of CRC death in the high-risk subjects (n = 12862, 84.48 per 10⁵ person-years) was 3.92 (95 % CI = 2.81-5.49) compared with the low-risk subjects (n = 69322, 18.52 per 10⁵ person-years). In the high-risk group, the age-adjusted RR of CRC death for those accepted colonoscopies (51.44 per 10⁵ person-years) compared with those refused colonoscopies (187.94 per 10⁵ person-years, P < 0.0001) was 0.34 (95 % CI = 0.21-0.56). The first three years after screening has seen the largest difference of CRC death hazard in both comparing groups.

CONCLUSION

The high-risk subjects triaged by the risk predicting system have a higher CRC mortality rate than the low-risk subjects, especially in the first three years after screening. Refusal of colonoscopy is risky behavior for the high-risk subject.

An early report of a screening program for colorectal cancer in Guangzhou, China

Background

We launched a screening program for colorectal cancer (CRC) in Yuexiu District, Guangzhou, China, in 2014. Here we aimed to report the early results of the program and evaluate the benefits of a screening questionnaire.

Methods

Residents aged between 50 and 74 were eligible for the screening. A questionnaire and two consecutive fecal immunological tests (FITs) were used as primary screening methods. Subjects who were positive for any of the two tests were referred for further examination with colonoscopy. Neoplasms were removed either colonoscopically or by colectomy. Atypical adenoma and CRC were defined as advanced neoplasms.

Results

A total of 6,971 residents in Dadong Street, Yuexiu District were screened with a questionnaire, and among them, 5,343 underwent at least one FIT. Four thousand and two hundred eleven (60.4%) were female, and 2,760 (39.6%) were male, with a median age of 62.0 years. Questionnaire and FITs identified 1,219 candidates for further examination with colonoscopy, among whom only 647 (53.1%) comply. As of this writing, 623 colonoscopy results were obtained, among which 270 (43.3%) had positive findings. The adenoma detection rate (ADR) was 43.3% (270/623). The ADR was 43.3% (270/623). Of the 270 patients, 10 (3.07%) had CRC, 81 (30.0%) had advanced adenoma, 178 had low-grade adenoma or other benign polyps, one had carcinoid. Except for three advanced CRC, all neoplasms detected were benign or in an early stage.

Conclusions

Our screening program help identified patients with colonic neoplasms at an early stage, precluding them from developing into the malignant disease. The addition of the questionnaire significantly increased the sensitivity of primary screening, while also decreasing the specificity. Long-term results should evaluate the social and economic benefits of this program.

Mass screening for colorectal cancer in a population of two million older adults in Guangzhou, China

Screening is an effective measure to prevent and control colorectal cancer (CRC). A mass CRC screening programme was conducted in Guangzhou from 2015 to 2017. Public media and reminders from a mobile short message service were used to invite residents aged between 50 and 74 years. A high-risk factor questionnaire (HRFQ) and biennial faecal immunochemical testing (FIT) were chosen as the primary screening methods, and individuals with a positive test result were referred to a defined hospital for an assessment colonoscopy. During the 3 years, 350,581 residents of the total eligible population of 2,283,214 attended the free first stage of screening. In all, 91.0% of the participants finished the HRFQs and FITs. The total uptake rate was 15.4%, which increased with age, female sex, and rural location. There was 15.9% positivity in the first stage of screening, including 8.5% positive HRFQs, 6.2% positive FITs and 1.2% positive HRFQs and FITs. In total, 10,600 individuals with positive HRFQs/FITs completed an assessment colonoscopy. The total uptake rate of colonoscopies was 18.9%, which decreased with age and female sex. Three hundred fifty-one CRCs and 980 advanced adenomas (AAs) were diagnosed with positive predictive values (PPV) of 3.3% and 9.2%, respectively. The PPVs of CRCs in the exclusively FIT-positive population were 4.9%, which was 10 times greater than in the exclusively HRFQ-positive population (0.5%). The PPVs of CRCs and AAs increased with age and male sex. The detection ratio of localized CRCs (including stage I and stage II) increased 68.1% due to screening. Although the compliance rate was low, the PPVs for CRCs and AAs were high. More effective mobilization of the programme's needs and subsidies for colonoscopies should be taken into account to increase compliance.

Colorectal Cancer Screening Modalities in Chinese Population: Practice and Lessons in Pudong New Area of Shanghai, China

Background: Parallel test of risk stratification and two-sample qualitative fecal immunochemical tests (FITs) are used to screen colorectal cancer (CRC) in Shanghai, China. This study was designed to identify an optimal initial screening modality based on available data. Methods: A total of 538,278 eligible residents participated in the program during the period of January 2013 to June 2017. Incident CRC was collected through program reporting system and by record linkage with the Shanghai Cancer Registry up to December 2017. Logistic regression model was applied to identify significant factors to calculate risk score for CRC. Cutoff points of risk score were determined based on Youden index and defined specificity. Sensitivity, specificity, and positive predictive values (PPVs) were computed to evaluate validity of assumed screening modalities. Results: A total of 446 CRC were screen-detected, and 777 interval or missed cases were identified through record linkage. The risk score system had an optimal cutoff point of 19 and performed better in detecting CRC and predicting long-term CRC risk than did the risk stratification. When using a cutoff point of 24, parallel test of risk score, and FIT were expected to avoid 56 interval CRCs with minimal decrease in PPV and increase in colonoscopy. However, the observed detection rates were much lower than those expected due to low compliance to colonoscopy. Conclusions: Risk score is superior to risk stratification used in the program, particularly when combined with FIT. Compliance to colonoscopy should be improved to guarantee the effectiveness of CRC screening in the population.

Effects of subitems in the colorectal cancer screening protocol on the Chinese colorectal cancer screening program: an analysis based on natural community screening results

Background

To date, no single colorectal cancer (CRC) screening strategy has been determined to be applicable worldwide. In China, a CRC screening protocol that combines double fecal immunochemical tests (FITs) and a high-risk factor questionnaire (HRFQ) as the first stage of screening and colonoscopy as the second stage of screening (scenario A) was adapted by the Chinese Ministry of Health in 2006. However, applying this CRC screening protocol nationally remains difficult because its effectiveness and convenience are controversial. This study evaluated the effects of subitems of the CRC screening protocol in China.

Methods

CRC screening results (scenario A) from Jiashan County, China, (2007–2009) were used to analyze the detection rates of CRC and advanced neoplasms as well as the cost-effectiveness of the protocol. Scenario A was divided into scenarios B–G (by selecting some items at the first stage of screening) for analysis.

Results

Compared with scenario A, removing the whole HRFQ (scenario F) reduced advanced neoplasm and adenoma detections by 29.8 and 41.2%, respectively, whereas the whole HRFQ accounted for 10.1% of the total screening cost. Removing FITs (scenario G) reduced CRC, advanced neoplasm and adenoma detections by 71.8, 56.9 and 47.7%, respectively, and the costs per case of CRC and advanced neoplasm were 82.0 and 19.1% higher, respectively, than those in scenario A.

In scenarios B–E (deleting some high-risk factor questions on the HRFQ), the odds ratios (ORs) of the detection rates and costs per CRC, advanced neoplasm, adenoma, and neoplasm case were near 1.00.

Scenarios C and D reduced the high-risk population and total screening costs by less than 6.0 and 4.1%, respectively. Scenarios E and B (FITs and a personal history of cancer or colorectal adenoma were reserved) reduced the high-risk population by 17.6 and 24.2% and the total screening costs by 11.2 and 15.4%, respectively, while the numbers of CRC cases were not missed, and advanced neoplasms detected decreased by only 5 and 11%, respectively.

Conclusion

The results of this study demonstrate that FITs and a personal history of colorectal adenoma are the most effective items in the Chinese CRC screening protocol.

Screening for colorectal cancer in Tianhe, Guangzhou: results of combining fecal immunochemical tests and risk factors for selecting patients requiring colonoscopy

Objective

To explore the performance of a protocol combining fecal immunochemical test (FIT) and a high-risk factor questionnaire (HRFQ) for selecting patients requiring colonoscopy as part of a population-based colorectal cancer (CRC) screening program in China.

Methods

From 2015 to 2016, we conducted a CRC screening program for all residents aged 45 years or older in Tianhe District, Guangzhou City, China. Participants underwent an FIT and received an HRFQ as part of primary screening. Those with positive FIT and/or HRFQ results were considered to be at high risk and were recommended to undergo colonoscopy.

Results

A total of 10 074 subjects were recruited and enrolled in the screening program. In the enrolled population, 17.5% had positive FIT results and 19.4% had positive HRFQ results. Of those recommended to undergo diagnostic colonoscopy, 773 did so. The screening method’s overall positive predictive value (PPV) was 4.9% for non-adenomatous polyps, 11.4% for low-risk adenomas (LRAs), 15.9% for high-risk adenomas (HRAs) and 1.6% for CRC. The PPVs of positive FIT results for non-adenomatous polyps, LRAs, HRAs and CRC were 5.2%, 15.9%, 22.5% and 2.5%, respectively. The PPVs of positive HRFQ results for non-adenomatous polyps, LRA, HRA and CRC were 4.1%, 10.2%, 14.3% and 1.4%, respectively. The PPVs associated with combined positive FIT and HRFQ results for non-adenomatous polyps, LRAs, HRAs and CRC were 4.5%, 16.4%, 23.7% and 2.8%, respectively.

Conclusion

Our results suggest that this two-step CRC screening strategy, involving a combination of FIT and HRFQ followed by colonoscopy, is useful to identify early-stage CRC. The high detection rates and PPVs for CRC and adenomas encourage this strategy’s use in ongoing screening programs.

Psychometric properties of a Chinese version of the Colorectal Cancer Perceptions Scale in a sample of older Chinese people

BACKGROUND

Older adults are more susceptible to colorectal cancer (CRC). Psychosocial constructs in the Health Belief Model are targets for interventional studies. No tool to measure these beliefs of older Chinese people has been validated.

OBJECTIVE

The present study aimed to examine the preliminary psychometric properties of the Chinese version of the Colorectal Cancer Perceptions Scale (CRCPS).

METHODS

The CRCPS was translated to Chinese language, validated by an expert panel, and tested. Interviewer-administered surveys were carried out with a convenience sample of 219 community-dwelling Chinese adults 60 years or older and were included in the analysis.

RESULTS

Six factors were retained, with items on susceptibility and benefits remaining as designed, whereas those on severity formed 2 factors, labeled severity-fear and severity-life impact, and those on barriers again formed 2 factors, labeled psychological barriers and knowledge barriers. Cronbach's α values ranged from .74 to .88, and test-retest reliability correlations ranged from .38 for psychological barriers to .69 for knowledge barriers. Respondents who had undergone CRC screening had significantly lower mean scores on severity-fear, severity-life impact, psychological barriers, and knowledge barriers compared with those who had not.

CONCLUSIONS

The results provide preliminary support for the reliability and validity of the Chinese version of the CRCPS. Further psychometric testing is recommended.

IMPLICATIONS FOR PRACTICE

The survey provides a useful tool to assess CRC health beliefs, which interventions should address to improve screening rates among older Chinese adults.

Cost-Effectiveness between Double and Single Fecal Immunochemical Test(s) in a Mass Colorectal Cancer Screening

This study investigated the cost-effectiveness between double and single Fecal Immunochemical Test(s) (FIT) in a mass CRC screening. A two-stage sequential screening was conducted. FIT was used as a primary screening test and recommended twice by an interval of one week at the first screening stage. We defined the first-time FIT as FIT1 and the second-time FIT as FIT2. If either FIT1 or FIT2 was positive (+), then a colonoscopy was recommended at the second stage. Costs were recorded and analyzed. A total of 24,419 participants completed either FIT1 or FIT2. The detection rate of advanced neoplasm was 19.2% among both FIT1+ and FIT2+, especially high among men with age ≥55 (27.4%). About 15.4% CRC, 18.9% advanced neoplasm, and 29.9% adenoma missed by FIT1 were detected by FIT2 alone. Average cost was $2,935 for double FITs and $2,121 for FIT1 to detect each CRC and $901 for double FITs and $680 for FIT1 to detect each advanced neoplasm. Double FITs are overall more cost-effective, having significantly higher positive and detection rates with an acceptable higher cost, than single FIT. Double FITs should be encouraged for the first screening in a mass CRC screening, especially in economically and medically underserved populations/areas/countries.

Serum M2-pyruvate kinase: A promising non-invasive biomarker for colorectal cancer mass screening

AIM: To explore the value of serum M2-pyruvate kinase (M2-PK) in colorectal cancer (CRC) mass screening.

METHODS: We conducted a molecular epidemiology study in Hangzhou, China, from year 2006 to year 2008. Serum samples were collected from 93 CRC, 41 advanced adenomas, 137 adenomas, 47 non-adenomatous polyps, and 158 normal participants in a community setting. Serum M2-PK and carcinoembryonic antigen (CEA) were measured using Enzyme-linked immunosorbent assay. SPSS 16.0 software was used to perform data analysis. Area under the receiver operating characteristic curve (AUC), sensitivity, and specificities were estimated for serum M2-PK in diagnosis of colorectal lesions and compared with CEA.

RESULTS: Average serum M2-PK value among 158 normal people was 2.96 U/mL and not affected by gender (P = 0.47) or age (P = 0.59). Average serum M2-PK (U/mL) was 14.75 among stage III and 13.10 among stage I and II CRC patients, about 4 times higher than that among normal people. Average serum M2-PK was 8.58, 6.70, 5.13 and 2.51 U/mL among advanced adenoma, adenomas, non-adenomatous polyps, and inflammatory bowel disease patients, respectively. AUC for serum M2-PK was greater than that for CEA among all colorectal lesions. AUC for serum M2-PK was 0.89 (0.84, 0.94) (95% confidence interval), higher than that for CEA [0.70 (0.62-0.79)] in CRC stage I and II, 0.89 (0.84-0.94) vs 0.73 (0.63-0.83) in CRC stage III, 0.81 (0.74-0.86) vs 0.63 (0.53 - 0.73) in advanced adenomas, 0.69 (0.64-0.76) vs 0.54 (0.47-0.60) in adenomas, and 0.69 (0.62-0.78) vs 0.58 (0.48-0.68) in non-adenomatous polyps. The diagnostic sensitivity for all colorectal lesions increased with decrease in the cut-off value of serum M2-PK. The diagnostic sensitivity (%) of serum M2-PK was 100.00 for CRC, 95.12 advanced adenoma, 82.48 adenoma, and 82.98 non-adenomatous polyp. There were no CRC cases missed and 40.51% of unnecessary colonoscopies were avoided when the cut-off value was 2.00 U/mL.

CONCLUSION: Serum M2-PK can be used as a primary screening test in CRC mass screening. It may be a promising non-invasive biomarker for CRC early detection.

Examining stools for colon cancer prevention: what are we really looking for?

Fecal immunochemical testing (FIT) is superior to guiac-based testing if we are looking for blood in stools, as it has better one-time colorectal cancer sensitivity and specificity and better patient acceptance. In this issue of the journal, Cai and colleagues (beginning on page 1572) and Khalid-de Bakker and colleagues (beginning on page 1563) present new information about the one-time test performance of FIT. FIT will have a growing appeal to providers and health care systems as resources for clinical preventive services shrink and as incentives to expand colorectal screening rates increase, but there are good reasons to be cautious about the temptation to organize new FIT screening programs. Colorectal screening has two potential objectives: To find cancers in an earlier, more-treatable stage and to find and remove adenomas to prevent cancers from forming in the first place. Because most adenomas, even advanced adenomas, do not bleed, tests designed to identify occult blood in the stool are better for detecting colorectal cancer, whereas direct endoscopic visualization of the colorectum is better for prevention. Even if advanced adenomas did commonly bleed, low compliance with repeat annual testing will seriously erode the benefit of FIT.