A Randomised Trial of the Impact of New Faecal Haemoglobin Test Technologies on Population Participation in Screening for Colorectal Cancer

Comparing a fecal immunochemical test and circulating tumor DNA blood test for colorectal cancer screening adherence

BACKGROUND AND AIM

Colorectal cancer (CRC) screening programs are most effective at reducing disease incidence and mortality through sustained screening participation. A novel blood test modality is being explored for CRC screening, but it is unclear whether it will provide sustained screening participation. This study aimed to investigate whether a circulating tumor DNA (ctDNA) blood test improved CRC screening re-participation when compared with a fecal immunochemical test (FIT) and to define the predictors of sustained CRC screening in an Australian population.

METHODS

South Australians who initially participated in CRC screening using a ctDNA blood test (n = 36) or FIT (n = 547) were offered the same CRC screening test approximately 2 years later through an extended phase of a randomized controlled trial. Surveys collected demographic, psychosocial, and clinical information. Predictors of CRC screening re-participation were explored using chi-square, Wilcoxon tests, and logistic regression.

RESULTS

Participants offered a second ctDNA blood test were equally likely to re-participate in CRC screening as those who completed a FIT in the first round and who were offered the same test (61% vs 66% re-participation respectively, P = 0.6). CRC fatalism, health activation, and self-efficacy were associated with repeated screening participation. Test awareness was predictive of repeated FIT-based CRC screening.

CONCLUSIONS

Targeted interventions to improve CRC screening awareness and increase patient health activation may improve CRC screening adherence. A ctDNA blood test may be a suitable CRC screening option to maintain CRC screening adherence in people who do not participate in screening with FIT.

Healthcare provider cultural competency and receptivity to colorectal cancer screening among African Americans

African Americans suffer disproportionately from colorectal cancer (CRC), due in part to disparities in CRC screening. Better understanding culturally relevant psychosocial factors that impact CRC screening is therefore critical. This study examined how African Americans' perceived cultural competency of their physician is associated with receptivity to take-home stool-based CRC screening. CRC screening deficient African Americans (N = 457) completed a patient-focused measure of perceived cultural competency and watched a brief video about CRC risks, prevention, and screening. Receptivity to stool-based CRC screening was measured using Theory of Planned Behavior (TPB) constructs . Participants were also given an opportunity to receive a no-cost at-home Fecal Immunochemical Test (FIT) kit, and we measured acceptance of this offer as a behavioral outcome (yes-no). Results showed that perceived cultural competency was associated with higher receptive attitudes, more favorable norms, greater perceived behavioral control towards stool-based screening, and also greater intentions to engage in FIT Kit screening (p < 0.001). We also found significant indirect effects of perceived cultural competency on FIT kit uptake through intention-mediated pathways. This study provides crucial evidence that participants' perceived cultural competency may play an important role in preventive health behavior among racial minorities, including CRC screening uptake among African Americans.

Disparities in Colorectal Cancer Screening Practices in a Midwest Urban Safety-Net Healthcare System

AIMS

Although colorectal cancer screening (CRC) using stool-based test is well-studied, evidence on fecal immunochemical test (FIT) patterns in a safety-net healthcare system utilizing opportunistic screening is limited. We studied the FIT completion rates and adenoma detection rate (ADR) of positive FIT-colonoscopy (FIT-C) in an urban safety-net system.

METHODS

We performed a retrospective cross-sectional chart review on individuals ≥ 50 years who underwent CRC screening using FIT or screening colonoscopy, 09/01/2017-08/30/2018. Demographic differences in FIT completion were studied; ADR of FIT-C was compared to that of screening colonoscopy.

RESULTS

Among 13,427 individuals with FIT ordered, 7248 (54%) completed the stool test and 230 (48%) followed up a positive FIT with colonoscopy. Increasing age (OR 1.01, CI 1.01-1.02), non-Hispanic Blacks (OR 0.87, CI 0.80-0.95, p = 0.002), current smokers (OR 0.84, CI 0.77-0.92, p < 0.0001), those with Medicaid (OR 0.86, CI 0.77-0.96, p = 0.006), commercial insurance (OR 0.85, CI 0.78-0.94, p = 0.002), CCI score ≥ 3 (OR 0.82, CI 0.74-0.91, p < 0.0001), orders by family medicine providers (OR 0.87, CI 0.81-0.94, p < 0.0001) were associated with lower completion of stool test. Individuals from low median household income cities had lower follow-up of positive FIT, OR 0.43, CI 0.21-0.86, p = 0.017. ADR of FIT-C was higher than that of screening colonoscopy.

CONCLUSION

Adherence to CRC screening is low in safety-net systems employing opportunistic screening. Understanding demographic differences may allow providers to formulate targeted strategies in high-risk vulnerable groups.

Inequalities in participation in colorectal cancer screening programmes: a systematic review

BACKGROUND

Colorectal cancer (CRC) is a major public health problem due to its incidence and mortality. Screening programmes help decrease its impact on the population through early detection. However, the uneven distribution of social determinants of health can cause inequalities. The aim of this study is to identify the social inequalities in the participation in CRC screening programmes.

METHODS

A systematic review of the literature was carried out, searching in both health and social databases for papers published since 2000 in English, Spanish, Portuguese and French. The search strategies combined terms regarding screening, CRC, participation and social inequalities. Included papers were quantitative or qualitative primary studies analyzing gender and socioeconomic inequalities in the participation in CRC screening programmes implemented by public and private health-care providers and addressing 45- to 75-year-old population.

RESULTS

A total of 96 studies, described in 102 articles, were included. Most were quantitative observational studies and analyzed population-based screening programmes. They were carried out mainly in the UK (n=29) and the USA (n=18). Participation in screening programmes varied from 1.1% to 82.8% using several methods. A total of 87 studies assessed participation by sex and one focussed on men, but only two provided an analysis from a gender perspective. Although men are at a higher risk of developing CRC, they generally were less likely to participate in screening programmes. Screening attendance was higher among the least deprived areas.

CONCLUSIONS

Gender and socioeconomic inequalities in CRC screening participation should be addressed through the design of tailored interventions with a multidimensional focus.

"Rescue" of Nonparticipants in Colorectal Cancer Screening: A Randomized Controlled Trial of Three Noninvasive Test Options

Few studies have directly targeted nonparticipants in colorectal cancer screening to identify effective engagement strategies. We undertook a randomized controlled trial that targeted nonparticipants in a previous trial of average-risk subjects which compared participation rates for mailed invitations offering a fecal test, a blood test or a choice of either. Nonparticipants (n = 899) were randomized to be offered a kit containing a fecal immunochemical test (FIT), directions on how to arrange a blood DNA test, or the option of doing either. Screening participation was assessed 12 weeks after the offer. To assess the cognitive and attitudinal variables related to participation and invitee choice, invitees were surveyed after 12 weeks, and associations were investigated using multinomial logistic regression. Participation rates were similar between groups (P = 0.88): 12.0% for FIT (35/292), 13.3% for the blood test (39/293), and 13.4% for choice (39/290). Within the choice group, participation was significantly higher with FIT (9.7%, 28/290) compared with the blood test (3.8%, 11/290, P = 0.005). The only variable significantly associated with participation was socioeconomic status when offered FIT, and age when offered choice but there was none when offered the blood test. Survey respondents indicated that convenience, time-saving, comfort, and familiarity were major influences on participation. There was no clear advantage between a fecal test, blood test, or choice of test although, when given a choice, the fecal test was preferred. Differences in variables associated with participation according to invitation strategy warrant consideration when deciding upon an invitation strategy for screening nonparticipants. PREVENTION RELEVANCE: This trial of screening for those at average risk for colorectal cancer targeted past fecal-test nonparticipants and compared participation rates for mailed invitations offering a fecal test, blood test, or choice of either. Although there was no clear advantage between strategies, factors associated with participation differed between each strategy.

Population-based organized screening by faecal immunochemical testing and colorectal cancer mortality: a natural experiment

BACKGROUND

Population-based organized screening programmes for colorectal cancer (CRC) are underway worldwide, with many based on the faecal immunochemical test (FIT). No clinical trials assessing FIT compared with no screening are planned, and few studies have assessed the population impact of such programmes.

METHODS

Before 2010, 11 out of 50 Spanish provinces initiated population-based organized screening programmes with FIT for an average-risk population aged 50-69 years. We used a quasi-experimental design across Spanish provinces between 1999 and 2016 to evaluate their impact on population age-standardized mortality and incidence rates due to CRC. Difference-in-differences and synthetic control analyses were performed to test for validation of statistical assumptions and to assess the dynamics of screening-associated changes in outcomes over time.

RESULTS

No differences in outcome trends between exposed (n = 11) and control (n = 36) provinces were observed for up to 7 years preceding the implementation of screening. Relative to controls, exposed provinces experienced a mean increase in age-standardized incidence of 10.08% [95% confidence interval (CI) (5.09, 15.07)] 2 years after implementation, followed by a reduction in age-standardized mortality rates due to CRC of 8.82% [95% CI (3.77, 13.86)] after 7 years. Results were similar for both women and men. No associated changes were observed in adjacent age bands not targeted by screening, nor for 10 other major causes of death in the exposed provinces.

CONCLUSIONS

FIT-based organized screening in Spain was associated with reductions in population colorectal cancer mortality. Further research is warranted in order to assess the replicability and external validity of our findings, and on gender-specific use of FIT in organized screening.

Effects of culturally targeted message framing on colorectal cancer screening among African Americans

OBJECTIVE

This study examined how standard and culturally targeted versions of gain and loss-framed messaging affect African Americans' colorectal cancer (CRC) screening receptivity and behavior, as well as their anticipation of experiencing racism in undertaking CRC screening.

METHOD

Screening-deficient African Americans (N = 457) viewed an informational video about CRC risks, prevention, and screening and were randomized to receive a gain or loss-framed message about screening. Half of participants viewed an additional culturally targeted message about overcoming racial disparities in CRC by obtaining screening. Using the Theory of Planned Behavior, we measured general receptivity to CRC screening. We also measured arousal of anticipatory racism in response to messaging. Finally, we offered participants a no-cost fecal immunochemical testing kit (FIT Kit) and measured uptake and use.

RESULTS

Message framing interacted with culturally targeted messaging to affect CRC screening receptivity and behavior. Participants were no more receptive to CRC screening when standard loss-framing was used, but were more favorable if loss-framing was culturally targeted. Targeted loss-framing also reduced anticipatory racism, which partially mediated effects on screening receptivity. Finally, although participants least often accepted a FIT Kit with standard loss-framing, effects of messaging on FIT Kit uptake and use were not significant.

CONCLUSION

This study adds to growing recognition of important cultural nuance in effective use of message framing. Current finding also suggest that targeted and framed messaging could synergistically impact the extent to which African Americans engage in CRC screening, although specific impacts on FIT Kit screening are less certain. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Variables Associated with Detection of Methylated BCAT1 or IKZF1 in Blood from Patients Without Colonoscopically Evident Colorectal Cancer

BACKGROUND

DNA methylated in BCAT1 and IKZF1 are promising circulating tumor DNA (ctDNA) biomarkers for colorectal cancer detection. This study tested for variables that might be associated with their detection in patients without colonoscopically evident colorectal cancer so-called false positives.

METHODS

A retrospective review of demographic and clinical variables was conducted on patients who were assayed for these biomarkers prior to a colonoscopy for any indication. Potential relationships between detection of these biomarkers and patient variables in patients without colorectal cancer were identified by logistic regression. An age- and sex-matched case-control study was undertaken to identify additional associations.

RESULTS

A total of 196 of 1,593 patients undergoing colonoscopy were positive for BCAT1 and/or IKZF1 methylation; 70 (35.7%) had confirmed diagnosis of colorectal cancer. Of the 126 false positives, biomarker levels were significantly lower than in those with colorectal cancer (P < 0.05), with the total cell-free circulating DNA concentration associated with biomarker detection (OR, 1.16; 95% CI, 1.10-1.22), and 83 (65.9%) of the non-colorectal cancer cases positive for methylated BCAT1 only. Age ≥70 years was the only demographic variable associated with biomarker detection (OR, 4.31; 95% CI, 1.50-12.41). No significant associations were seen with medications or comorbidities (P > 0.05). Four cases without colonoscopically evident colorectal cancer but with biomarker levels above the median for patients with colorectal cancer were diagnosed with metastatic adenocarcinoma within 1 year.

CONCLUSIONS

False-positive results were most commonly associated with detection of methylated BCAT1 only, as well as age ≥70 years.

IMPACT

In the absence of colonoscopically evident colorectal cancer, a high level of circulating methylated DNA warrants investigations for cancers at other sites.

Implementation Strategies for Interventions Aiming to Increase Participation in Mail-Out Bowel Cancer Screening Programs: A Realist Review

Background: Bowel cancer is the third most commonly diagnosed cancer and the third most common cause of cancer-related death, with 1,849,518 new cases of bowel diagnosed and 880,792 deaths reported globally in 2018 alone. Survival can be improved through early detection via national mail-out bowel cancer screening programs; however, participation remains low in many countries. Behavior change is therefore required to increase participation. This realist review aims to (a) identify the behavior change techniques (BCTs) used in each intervention, (b) understand the mechanisms of action (MoAs) responsible for the BCT effectiveness, and (c) apply a behavior change model to inform how MoAs can be combined to increase screening participation.

Methods: We systematically reviewed the literature for interventions aiming to increase participation in mail-out bowel cancer screening. We used a four-stage realist synthesis approach whereby (1) interventions were extracted from each study; (2) BCTs applied in each intervention were identified and coded using the BCT Taxonomy-v1; (3) the Theory and Techniques Tool was used to link BCTs to their MoA; and (4) BCTs and MoAs were categorized according to their effectiveness and what Health Action Process Approach (HAPA) stage of change they would affect.

Results: We identified 68 intervention trials using 26 unique BCTs and 13 MoAs to increase participation. Sixteen BCTs and 10 MoAs were identified within the interventions that successfully increased participation rates. Interventions targeting both stages of the HAPA model had a higher success rate (80%) than those targeting one stage of change (51%). When targeting only one stage, interventions targeting the volitional stage had a higher success rate (71%) than interventions targeting only the motivational stage of change (26%).

Conclusion: Importantly, this review identified a suite of BCTs and MoAs effective for increasing participation in mail-out bowel cancer screening programs. With increased participation in bowel cancer screening leading to improved survival, our findings are key to informing the improvement of policy and interventions that aim to increase screening using specific strategies at key stages of health decision-making.

Strategies for increasing participation in mail-out colorectal cancer screening programs: a systematic review and meta-analysis

BACKGROUND

Population mail-out bowel screening programs are a convenient, cost-effective and sensitive method of detecting colorectal cancer (CRC). Despite the increased survival rates associated with early detection of CRC, in many countries, 50% or more of eligible individuals do not participate in such programs. The current study systematically reviews interventions applied to increase fecal occult blood test (FOBT) kit return, specifically in population mail-out programs.

METHODS

Five electronic databases (PubMed, PsycINFO, Scopus, CINAHL, and ProQuest Dissertations and Theses) were searched for articles published before the 10th of March 2018. Studies were included if they reported the results of an intervention designed to increase the return rate of FOBT kits that had been mailed to individuals' homes. PRISMA systematic review reporting methods were applied and each study was assessed using Cochrane's Risk of Bias tool. Pooled effect sizes were calculated for each intervention type and the risk of bias was tested as a moderator for sensitivity analysis.

RESULTS

The review identified 53 interventions from 30 published studies from which nine distinct intervention strategy types emerged. Sensitivity analysis showed that the risk of bias marginally moderated the overall effect size. Pooled risk ratios and confidence intervals for each intervention type revealed that telephone contact RR = 1.23, 95% CI (1.08-1.40), GP endorsement RR = 1.19, 95% CI (1.10-1.29), simplified test procedures RR = 1.17, 95% CI (1.09-1.25), and advance notifications RR = 1.09, 95% CI (1.07-1.11) were effective intervention strategies with small to moderate effect sizes. Studies with a high risk of bias were removed and pooled effects remained relatively unchanged.

CONCLUSIONS

Interventions that combine program-level changes incorporating the issue of advance notification and alternative screening tools with the involvement of primary health professionals through endorsement letters and telephone contact should lead to increases in kit return in mail-out CRC screening programs.

SYSTEMATIC REVIEW REGISTRATION

This review is registered with PROSPERO; registration number CRD42017064652.

Effect of Imperfect Compliance With Instructions for Fecal Sample Collection on Diagnostic Performance of 9 Fecal Immunochemical Tests

BACKGROUND & AIMS

Fecal immunochemical tests (FITs) measure hemoglobin in stool to identify individuals at risk for colorectal cancer (CRC). However, there are many different FITs, with different instructions for fecal sample collection. In routine practice, participants do not always follow these instructions exactly. We assessed the effects of violations of fecal sampling instructions on the diagnostic performance of 9 quantitative FITs.

METHODS

We obtained stool samples from 76 patients with CRC scheduled for surgery at 4 hospitals in Germany and 100 participants without advanced neoplasms who participated in a prospective colonoscopy screening program. We filled fecal sample tubes according to the manufacturers' instructions or with 3 violations that are likely to occur in routine practice. The diagnostic performance was assessed for a total of 6336 FIT samples (176 participants × 9 FITs × 4 sampling methods).

RESULTS

Sample collection instructions varied widely among FITs but included 3 key components: multiple insertions of the sampling rod into stool, a visual check of rod for complete filling with stool, and once-only insertion of the stool-filled rod into the tube. Violation of the first 2 components (inserting the rod into the stool sample only 1 time or not visually checking the rod for complete filling) reduced levels of hemoglobin measured. However, the effect on diagnostic performance was generally small. Violation of the third component (insertion of more stool into the tube than recommended) increased levels of hemoglobin measured in samples and identified more patients with CRC (increase of median sensitivity by almost 10% units) at a small loss of specificity (decrease of median specificity by 2% units), and produced the highest area under the curve for detection of CRC cases for 6 FITs.

CONCLUSIONS

Violations of fecal sampling instructions can lead to non-negligible variations in fecal hemoglobin measurements. The limited adverse effects on diagnostic performance indicate the robustness of FITs. The potential for increasing diagnostic performance by collecting more stool material should be followed up in further research.

A Randomized Controlled Trial Testing Provision of Fecal and Blood Test Options on Participation for Colorectal Cancer Screening

Suboptimal participation is commonly observed in colorectal cancer screening programs utilizing fecal tests. This randomized controlled trial tested whether the offer of a blood test as either a "rescue" strategy for fecal test nonparticipants or an upfront choice, could improve participation. A total of 1,800 people (50-74 years) were randomized to control, rescue, or choice groups (n = 600/group). All were mailed a fecal immunochemical test (FIT, OC-Sensor, Eiken Chemical Company) and a survey assessing awareness of the screening tests. The rescue group was offered a blood test 12 weeks after FIT nonparticipation. The choice group was given the opportunity to choose to do a blood test (Colvera, Clinical Genomics) instead of FIT at baseline. Participation with any test after 24 weeks was not significantly different between groups (control, 37.8%; rescue, 36.9%; choice, 33.8%; P > 0.05). When the rescue strategy was offered after 12 weeks, an additional 6.5% participated with the blood test, which was greater than the blood test participation when offered as an upfront choice (1.5%; P < 0.001). Awareness of the tests was greater for FIT than for blood (96.2% vs. 23.1%; P < 0.0001). In a population familiar with FIT screening, provision of a blood test either as a rescue of FIT nonparticipants or as an upfront choice did not increase overall participation. This might reflect a lack of awareness of the blood test for screening compared with FIT.

Ways to use interventions to increase participation in mail-out bowel cancer screening: a systematic review and meta-analysis

The impact of colorectal cancer can be reduced through nationwide fecal occult blood test (FOBT) screening. Unfortunately, participation in screening programs are low with interventions only increasing participation modestly.

This meta-analysis explores if intervention effectiveness can be increased by targeting specific subpopulations with specific interventions or by combining interventions. Six databases were searched for studies aiming to increase participation in mail-out FOBT screening. To investigate if interventions are more effective for certain subpopulations, the difference in (log) Risk Ratios (RRs) between alternate subpopulations (male vs. female; low vs. high Socioeconomic Status (SES); &lt;65 vs. ≥65 years) was assessed. To investigate if interventions should be combined, uptake rates for single interventions were compared to uptake rates for combined interventions. Cochrane Collaboration tools were used to assess the risk of bias.

Searches found 3,436 articles, with 32 meeting the inclusion criteria. These contained 30 trials that reported uptake rates within subpopulations and 17 trials that combined interventions. Most differences in intervention effects between subpopulations were nonsignificant. Combining interventions led to greater participation, RR = 1.06, confidence interval [1.03; 1.10]. As interventions rarely affect subpopulations differently, targeting them at specific subpopulations may be an ineffective strategy. While individual interventions show modest effects, these results indicate that future programs might overcome this by combining interventions together. Care is needed when selecting interventions to combine as adding some interventions (e.g., additional print materials) can reduce the effectiveness of a combined strategy. Future research should examine methods for effectively combining interventions in nationwide programs to maximize participation.

The Impact of Transitioning From Guaiac-Fecal Occult Blood Testing to Fecal Immunochemical Testing in a Canadian Colon Cancer Screening Program

Objectives

To determine the impact of transitioning from guaiac-based fecal occult blood testing (gFOBT) to fecal immunochemical testing (FIT) on the detection rate of adenomas, advanced adenomas (AA) and colorectal cancer (CRC).

Background

Recently, the health region in Edmonton, Alberta switched from gFOBT to FIT for CRC screening.

Study

A retrospective analysis of all patients, aged 50 to 74 years, referred for colonoscopy from January 1, 2013 to December 31, 2014 due to a positive gFOBT (at least one of three samples positively using the guaiac-based Hemoccult II SENSA in 2013) or FIT (≥75 µg/g of stool, using the Polymedco OC FIT-CHEK in 2014). The primary outcomes were the number of colon cancers, AA and adenomas detected in 2013 and 2014. A comparison between the two tests was also made for the composite outcome of detection of either AA or CRC.

Results

Six hundred and forty-nine patients underwent colonoscopy due to a positive gFOBT in 2013, and 2167 patients for a positive FIT in 2014. FIT compared with gFOBT detected more CRC (67 compared with 34), AA (770 compared with 147) and adenomas (1575 versus 320). By multivariable regression analysis adjusted for different demographics and endoscopic metrics, positive FIT was independently associated with higher adenoma detection rate (odds ratio [OR] 2.62; 95% confidence interval [CI] 2.13 to 3.21, P < 0.001), AA detection rate (OR 1.83, 95% CI 1.43 to 2.33, P < 0.001), and the composite outcome of AA and CRC (OR 2.04, 95% CI 1.60 to 2.59, P < 0.001).

Conclusions

Adoption of FIT compared with gFOBT led to higher detection of colon cancer, AA and adenomas.

Uptake of a colorectal cancer screening blood test in people with elevated risk for cancer who cannot or will not complete a faecal occult blood test

Participation rates in colorectal cancer (CRC) screening programmes using faecal occult blood tests (FOBTs) are low. Nonparticipation is commonly attributed to psychosocial factors, but some medical conditions also prevent screening. These barriers might be partially overcome if a blood test for CRC screening was available. This study determined whether people who had always declined screening by FOBT would participate if offered a blood test. An audit of registrants within a personalized CRC screening programme was undertaken to determine the reasons for regular nonparticipation in FOBT. Consistent nonparticipants (n=240) were randomly selected and invited for CRC screening with a blood test. Demographic characteristics and the reasons for prior FOBT nonparticipation were collected by means of a questionnaire. Nonparticipation in the screening programme could be classified as either behavioural (8.6%), with consistent noncompliance, or due to medical contraindications (8.5%), which included chronic rectal bleeding, being deemed unsuitable by a health professional, and needing personal assistance. Blood test uptake was 25%, with participation in the medical contraindications group greater than that in the behavioural group (43 vs. 12%, P<0.001). Reported behavioural reasons for nonparticipation in faecal immunochemical test included procrastination and dislike of the test, but these were not associated with blood test uptake (P>0.05). There is a subgroup of the community who have medical reasons for nonparticipation in CRC screening with FOBT but will participate if offered a blood test. The option of a blood test does not, however, improve uptake in those who admit to behavioural reasons for noncompliance with screening.

Participation and Ease of Use in Colorectal Cancer Screening: A Comparison of 2 Fecal Immunochemical Tests

INTRODUCTION

The impact of fecal immunochemical test (FIT)-based colorectal cancer (CRC) screening on disease incidence and mortality is affected by participation, which might be influenced by ease of use of the FIT. We compared the participation rates and ease of use of 2 different FITs in a CRC screening program.

METHODS

There were two study designs within the Dutch CRC screening program. In a paired cohort study, all invitees received 2 FITs (OC-Sensor, Eiken, Japan, and FOB-Gold, Sentinel, Italy) and were asked to sample both from the same stool. Ease of use of both FITs was evaluated by a questionnaire. In a randomized controlled trial, invitees were randomly allocated to receive one of the 2 FITs to compare participation and analyzability.

RESULTS

Of 42,179 invitees in the paired cohort study, 21,078 (50%) completed 2 tests and 20,727 (98%) returned the questionnaire. FOB-Gold was reported significantly easier to use. More participants preferred FOB-Gold (36%) than OC-Sensor (5%), yet most had no preference (59%; P < 0.001). In the randomized trial, 936 of 1,923 invitees (48.7%) returned the FOB-Gold and 940 of 1,923 invitees (48.9%) returned the OC-Sensor, a difference of -0.2% (confidence interval, -3.4% to 3.0%), well within the pre-specified 5% noninferiority margin (P = 0.001). Only one FOB-Gold (0.1%) and 4 OC-Sensors (0.4%) were not analyzable (P = 0.18).

CONCLUSIONS

Although FOB-Gold was significantly but marginally considered easier to use than OC-Sensor, the number of analyzable tests and the participation rates in organized CRC screening are not affected when either of the FITs is implemented as a primary screening test.

Colorectal Cancer Biomarkers - A New Trend in Early Diagnosis

Colorectal cancer (CRC) is one of the most widespread malignancy, posing as a great challenge due to its high incidence and mortality in both genders. Yet, it also stands as one of the most preventable diseases because of its known malignant transformation mostly from tubular adenomas or serrated polyps, therefore offering a strong incentive to the screening programs that are being developed for this disease. Current diagnosis of CRC has surely evolved along with the evolutionary step in gastrointestinal technology of flexible endoscopy. These innovations have promoted colonoscopy as a primary choice for screening programs of colonic lesions, proving to be of great benefit for patient’s well-being. In this review, we present the current status of CRC screening methods from the non-invasive options to the long developed colonoscopic and imaging techniques. We search through PubMed and Medline databases and chose relevant articles on CRC with focus on blood based biomarkers and stool based tests. Additional relevant publications were also according to the reference lists of firstly identified articles.

Effect of Physician Notification Regarding Nonadherence to Colorectal Cancer Screening on Patient Participation in Fecal Immunochemical Test Cancer Screening: A Randomized Clinical Trial

IMPORTANCE

Increasing participation in fecal screening tests is a major challenge in countries that have implemented colorectal cancer (CRC) screening programs.

OBJECTIVE

To determine whether providing general practitioners (GPs) a list of patients who are nonadherent to CRC screening enhances patient participation in fecal immunochemical testing (FIT).

DESIGN, SETTING, AND PARTICIPANTS

A 3-group, cluster-randomized study was conducted from July 14, 2015, to July 14, 2016, on the west coast of France, with GPs in 801 practices participating and involving adult patients (50-74 years) who were at average risk of CRC and not up-to-date with CRC screening. The final follow-up date was July 14, 2016.

INTERVENTIONS

General practitioners were randomly assigned to 1 of 3 groups: 496 received a list of patients who had not undergone CRC screening (patient-specific reminders group, 10 476 patients), 495 received a letter describing region-specific CRC screening adherence rates (generic reminders group, 10 606 patients), and 455 did not receive any reminders (usual care group, 10 147 patients).

MAIN OUTCOMES AND MEASURES

The primary end point was patient participation in CRC screening 1 year after the intervention.

RESULTS

Among 1482 randomized GPs (mean age, 53.4 years; 576 women [38.9%]), 1446 participated; of the 33 044 patients of these GPs (mean age, 59.7 years; 17 949 women [54.3%]), follow-up at 1 year was available for 31 229 (94.5%). At 1 year, 24.8% (95% CI, 23.4%-26.2%) of patients in the specific reminders group, 21.7% (95% CI, 20.5%-22.8%) in the generic reminders group, and 20.6% (95% CI, 19.3%-21.8%) in the usual care group participated in the FIT screening. The between-group differences were 3.1% (95% CI, 1.3%-5.0%) for the patient-specific reminders group vs the generic reminders group, 4.2% (95% CI, 2.3%-6.2%) for the patient-specific reminders group vs the usual care group, and 1.1% (95% CI, -0.6% to 2.8%) for generic reminders group vs the usual care group.

CONCLUSIONS AND RELEVANCE

Providing French GPs caring for adults at average risk of CRC with a list of their patients who were not up-to-date with their CRC screening resulted in a small but significant increase in patient participation in FIT screening at 1 year compared with patients who received usual care. Providing GPs with generic reminders about regional rates of CRC screening did not increase screening rates compared with usual care.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02515344.

"Finding the Right FIT": Rural Patient Preferences for Fecal Immunochemical Test (FIT) Characteristics

PURPOSE

Colorectal cancer (CRC) is the third leading cause of cancer death in the United States, yet 1 in 3 Americans have never been screened for CRC. Annual screening using fecal immunochemical tests (FITs) is often a preferred modality in populations experiencing CRC screening disparities. Although multiple studies evaluate the clinical effectiveness of FITs, few studies assess patient preferences toward kit characteristics. We conducted this community-led study to assess patient preferences for FIT characteristics and to use study findings in concert with clinical effectiveness data to inform regional FIT selection.

METHODS

We collaborated with local health system leaders to identify FITs and recruit age eligible (50 to 75 years), English or Spanish speaking community members. Participants completed up to 6 FITs and associated questionnaires and were invited to participate in a follow-up focus group. We used a sequential explanatory mixed-methods design to assess participant preferences and rank FIT kits. First, we used quantitative data from user testing to measure acceptability, ease of completion, and specimen adequacy through a descriptive analysis of 1) fixed response questionnaire items on participant attitudes toward and experiences with FIT kits, and 2) a clinical assessment of adherence to directions regarding collection, packaging, and return of specimens. Second, we analyzed qualitative data from focus groups to refine FIT rankings and gain deeper insight into the pros and cons associated with each tested kit.

FINDINGS

Seventy-six FITs were completed by 18 participants (Range, 3 to 6 kits per participant). Over half (56%, n = 10) of the participants were Hispanic and 50% were female (n = 9). Thirteen participants attended 1 of 3 focus groups. Participants preferred FITs that were single sample, used a probe and vial for sample collection, and had simple, large-font instructions with colorful pictures. Participants reported challenges using paper to catch samples, had difficulty labeling tests, and emphasized the importance of having care team members provide verbal instructions on test completion and follow-up support for patients with abnormal results. FIT rankings from most to least preferred were OC-Light, Hemosure iFOB Test, InSure FIT, QuickVue, OneStep+, and Hemoccult ICT.

CONCLUSIONS

FIT characteristics influenced patient's perceptions of test acceptability and feasibility. Health system leaders, payers, and clinicians should select FITs that are both clinically effective and incorporate patient preferred test characteristics. Consideration of patient preferences may facilitate FIT return, especially in populations at higher risk for experiencing CRC screening disparities.

Colorectal Cancer Screening: Stool DNA and Other Noninvasive Modalities

Colorectal cancer screening dates to the discovery of pre-cancerous adenomatous tissue. Screening modalities and guidelines directed at prevention and early detection have evolved and resulted in a significant decrease in the prevalence and mortality of colorectal cancer via direct visualization or using specific markers. Despite continued efforts and an overall reduction in deaths attributed to colorectal cancer over the last 25 years, colorectal cancer remains one of the most common causes of malignancy-associated deaths. In attempt to further reduce the prevalence of colorectal cancer and associated deaths, continued improvement in screening quality and adherence remains key. Noninvasive screening modalities are actively being explored. Identification of specific genetic alterations in the adenoma-cancer sequence allow for the study and development of noninvasive screening modalities beyond guaiac-based fecal occult blood testing which target specific alterations or a panel of alterations. The stool DNA test is the first noninvasive screening tool that targets both human hemoglobin and specific genetic alterations. In this review we discuss stool DNA and other commercially available noninvasive colorectal cancer screening modalities in addition to other targets which previously have been or are currently under study.

Fecal Immunochemical Test (FIT) for Colon Cancer Screening: Variable Performance with Ambient Temperature

INTRODUCTION

Fecal immunochemical tests (FITs) are widely used in colorectal cancer (CRC) screening, but hemoglobin degradation, due to exposure of the collected sample to high temperatures, could reduce test sensitivity. We examined the relation of ambient temperature exposure with FIT positivity rate and sensitivity.

METHODS

This was a retrospective cohort study of patients 50 to 75 years in Kaiser Permanente Northern California's CRC screening program, which began mailing FIT kits annually to screen-eligible members in 2007. Primary outcomes were FIT positivity rate and sensitivity to detect CRC. Predictors were month, season, and daily ambient temperatures of test result dates based on US National Oceanic and Atmospheric Administration data.

RESULTS

Patients (n = 472,542) completed 1,141,162 FITs. Weekly test positivity rate ranged from 2.6% to 8.0% (median, 4.4%) and varied significantly by month (June/July vs December/January rate ratio [RR] = 0.79, 95% confidence interval [CI], 0.76 to 0.83) and season. FIT sensitivity was lower in June/July (74.5%; 95% CI, 72.5 to 76.6) than January/December (78.9%; 95% CI, 77.0 to 80.7).

CONCLUSIONS

FITs completed during high ambient temperatures had lower positivity rates and lower sensitivity. Changing kit design, specimen transportation practices, or avoiding periods of high ambient temperatures may help optimize FIT performance, but may also increase testing complexity and reduce patient adherence, requiring careful study.

Recommendations for a step-wise comparative approach to the evaluation of new screening tests for colorectal cancer

BACKGROUND

New screening tests for colorectal cancer continue to emerge, but the evidence needed to justify their adoption in screening programs remains uncertain.

METHODS

A review of the literature and a consensus approach by experts was undertaken to provide practical guidance on how to compare new screening tests with proven screening tests.

RESULTS

Findings and recommendations from the review included the following: Adoption of a new screening test requires evidence of effectiveness relative to a proven comparator test. Clinical accuracy supported by programmatic population evaluation in the screening context on an intention-to-screen basis, including acceptability, is essential. Cancer-specific mortality is not essential as an endpoint provided that the mortality benefit of the comparator has been demonstrated and that the biologic basis of detection is similar. Effectiveness of the guaiac-based fecal occult blood test provides the minimum standard to be achieved by a new test. A 4-phase evaluation is recommended. An initial retrospective evaluation in cancer cases and controls (Phase 1) is followed by a prospective evaluation of performance across the continuum of neoplastic lesions (Phase 2). Phase 3 follows the demonstration of adequate accuracy in these 2 prescreening phases and addresses programmatic outcomes at 1 screening round on an intention-to-screen basis. Phase 4 involves more comprehensive evaluation of ongoing screening over multiple rounds. Key information is provided from the following parameters: the test positivity rate in a screening population, the true-positive and false-positive rates, and the number needed to colonoscope to detect a target lesion.

CONCLUSIONS

New screening tests can be evaluated efficiently by this stepwise comparative approach.

A Blood Test for Methylated BCAT1 and IKZF1 vs. a Fecal Immunochemical Test for Detection of Colorectal Neoplasia

Objectives:

To compare the performance of a new blood test for colorectal cancer (CRC) to an established fecal immunochemical test (FIT) in a study population with the full range of neoplastic and non-neoplastic pathologies encountered in the colon and rectum.

Methods:

Volunteers were asked to complete a FIT prior to colonoscopy. Blood was collected after bowel preparation but prior to colonoscopy, and plasma was assayed for the presence of methylated BCAT1 and IKZF1 DNA using a multiplex real-time PCR assay. Sensitivity and specificity estimates for the blood test were calculated from true- and false-positive rates for neoplasia and compared with FIT at a range of fecal hemoglobin (Hb) concentration positivity thresholds.

Results:

In total, 1,381 volunteers (median age 64 years; 49% male) completed both tests prior to colonoscopy. Estimated sensitivity of the BCAT1/IKZF1 blood test for CRC was 62% (41/66; 95% confidence interval 49–74%) with a specificity of 92% (1207/1315; 90–93%). FIT returned the same specificity at a cutoff of 60 μg Hb/g, at which its corresponding sensitivity for cancer was 64% (42/66; 51–75%). In the range of commonly used FIT cutoffs, respective cancer sensitivity and specificity estimates with FIT were: 59% (46–71%) and 93% (92–95%) at 80 μg Hb/g, and 79% (67–88%) and 81% (78–83%) at 10 μg Hb/g. Although estimated sensitivities were not significantly different between the two tests for any stage of cancer, FIT showed a significantly higher sensitivity for advanced adenoma at the lower cutoffs. Specificity of FIT, but not of the BCAT1/IKZF1 blood test, deteriorated substantially in people with overt blood in the feces. When combining FIT (cutoff 10 μg Hb/g) with the BCAT1/IKZF1 blood test, sensitivity for cancer was 89% (79–96%) at 74% (72–77%) specificity.

Conclusions:

A test based on detection of methylated BCAT1/IKZF1 DNA in blood has comparable sensitivity but better specificity for CRC than FIT at the commonly used positivity threshold of 10 μg Hb/g. Further evaluation of the new test relative to FIT in the population screening context is now required to fully understand the potential advantages and disadvantages of these biomarkers in screening.

Correlating Quantitative Fecal Immunochemical Test Results with Neoplastic Findings on Colonoscopy in a Population-Based Colorectal Cancer Screening Program: A Prospective Study

Background and Aims. The Canadian Partnership Against Cancer (CPAC) recommends a fecal immunochemical test- (FIT-) positive predictive value (PPV) for all adenomas of ≥50%. We sought to assess FIT performance among average-risk participants of the British Columbia Colon Screening Program (BCCSP). Methods. From Nov-2013 to Dec-2014 consecutive participants of the BCCSP were assessed. Data was obtained from a prospectively collected database. A single quantitative FIT (NS-Plus, Alfresa Pharma Corporation, Japan) with a cut-off of ≥10 μg/g (≥50 ng/mL) was used. Results. 20,322 FIT-positive participants underwent CSPY. At a FIT cut-off of ≥10 μg/g (≥50 ng/mL) the PPV for all adenomas was 52.0%. Increasing the FIT cut-off to ≥20 μg/g (≥100 ng/mL) would increase the PPV for colorectal cancer (CRC) by 1.5% and for high-risk adenomas (HRAs) by 6.5% at a cost of missing 13.6% of CRCs and 32.4% of HRAs. Conclusions. As the NS-Plus FIT cut-off rises, the PPV for CRC and HRAs increases but at the cost of missed lesions. A cut-off of ≥10 μg/g (≥50 ng/mL) produces a PPV for all adenomas exceeding national recommendations. Health authorities need to take into consideration endoscopic resources when selecting a FIT positivity threshold.

Participant uptake of the fecal immunochemical test decreases with the two-sample regimen compared with one-sample FIT

BACKGROUND

Fecal immunochemical tests (FITs) are recommended to screen average-risk adults for colorectal cancer (CRC). Little research has examined whether a two-sample FIT affects participant uptake, compared with a one-sample FIT. Examining participant uptake is important, as evidence suggests that a two-sample FIT may increase the sensitivity to detect CRC.

OBJECTIVE

This study had two objectives: (i) to evaluate FIT completion in a population that received either a one-sample FIT kit (1-FIT) or a two-sample FIT kit (2-FIT) and (ii) to understand whether uptake varies by age, sex, or receipt of prior CRC screening.

METHODS

We conducted a randomized controlled trial in which 3081 participants who were aged between 50 and 75 years and were at an average risk for CRC, and who had requested FITs, randomly received 1-FIT (n=1540) or 2-FIT (n=1541) kits. FIT completion was defined as the completion and return of a one-sample test by the patients in the 1-FIT group or of both sample tests by those in the 2-FIT group. Cox proportional hazard regression models were used to determine the independent effect of group type (2-FIT vs. 1-FIT) on the completion of the FIT, adjusting for age, sex, and receipt of prior CRC screening.

RESULTS

The 2-FIT group had lower test completion rates (hazard ratio=0.87; 95% confidence interval=0.78-0.97; P=0.01) after adjusting for age, sex, and receipt of prior CRC screening. Participant uptake did not vary by age, sex, or receipt of prior CRC screening.

CONCLUSION

This unique, rigorous randomized controlled trial found that the 2-FIT regimen decreases completion of FIT. Further research is needed to understand whether decreases in participant uptake are offset by increased gains in test sensitivity.

Factors affecting faecal immunochemical test positive rates: demographic, pathological, behavioural and environmental variables

OBJECTIVES

Positive rates in faecal immunochemical test (FIT)-based colorectal cancer screening programmes vary, suggesting that differences between programmes may affect test results. We examined whether demographic, pathological, behavioural, and environmental factors affected haemoglobin concentration and positive rates where samples are mailed.

METHODS

A retrospective cohort study; 34,298 collection devices were sent, over five years, to screening invitees (median age 60.6). Participant demographics, temperature on sample postage day, and previous screening were recorded. Outcomes from colonoscopy performed within a year following FIT were collected. Multivariate logistic regression identified significant predictors of test positivity.

RESULTS

Higher positive rate was independently associated with male gender, older age, lower socioeconomic status, and distally located neoplasia, and negatively associated with previous screening (p < 0.05). Older males had higher faecal haemoglobin concentrations and were less likely to have a false positive result at colonoscopy (p < 0.05). High temperature on the sample postage day was associated with reduced haemoglobin concentration and positivity rate (26-35℃: Odds ratio 0.78, 95% confidence interval 0.66-0.93), but was not associated with missed significant neoplasia at colonoscopy (p > 0.05).

CONCLUSIONS

Haemoglobin concentrations, and therefore FIT positivity, were affected by factors that vary between screening programmes. Participant demographics and high temperature at postage had significant effects. The impact of temperature could be reduced by seasonal scheduling of invitations. The importance of screening, and following up positive test results, particularly in older males, should be promoted.

Improving uptake of screening for colorectal cancer: a study on invitation strategies and different test kit use

OBJECTIVE

The aim of this study was to compare the uptake of mail-delivered tests for colorectal cancer screening. We assessed the effect of an advance notification letter and a reminder letter, and analysed the proportion of inappropriately handled tests.

MATERIALS AND METHODS

Fifteen thousand randomly selected residents of Latvia aged 50-74 years were allocated to receive one of three different test systems: either a guaiac faecal occult blood test (gFOBT) or one of two laboratory-based immunochemical tests (FIT) - FOB Gold or OC-Sensor. Half of the target population received an advance notification letter; all nonresponders were sent a reminder letter.

RESULTS

The uptake of screening was 31.2% for the gFOBT, 44.7% for FOB Gold and 47.4% for the OC-Sensor (odds ratio 0.55; 95% confidence interval 0.51-0.60 for gFOBT vs. FOB Gold; odds ratio 0.90; 95% confidence interval 0.83-0.98 for FOB Gold vs. OC-Sensor). The uptake in the gFOBT group was improved by the advance notification letter (7.7%, P<0.0001). 30.9% returned tests were received after the reminder letter. The proportion of tests that could not be analysed because of inadequate handling was 0.9% for gFOBT, 4.4% for FOB Gold and 0.2% for the OC-Sensor (P=0.002 for gFOBT vs. OC-Sensor; P<0.001 for all comparisons vs. FOB Gold).

CONCLUSION

The use of FIT resulted in higher uptake. Receipt of a reminder letter was critical to participation, but the use of an advance notification letter was important mainly for gFOBT. The proportion of inappropriately handled tests was markedly higher for FOB Gold.

Reducing inequities in colorectal cancer screening in North America

Colorectal cancer (CRC) is an important cause of mortality and morbidity in North America. Screening using a fecal occult blood test, flexible sigmoidoscopy, or colonoscopy reduces CRC mortality through the detection and treatment of precancerous polyps and early stage CRC. Although CRC screening participation has increased in recent years, large inequities still exist. Minorities, new immigrants, and those with lower levels of education or income are much less likely to be screened. This review provides an overview of the commonly used tests for CRC screening, disparities in CRC screening, and promising methods at the individual, provider, and system levels to reduce these disparities. Overall, to achieve high CRC participation rates and reduce the burden of CRC in the population, a multi-faceted approach that uses strategies at all levels to reduce CRC screening disparities is urgently required.

Colorectal cancer screening: tests, strategies, and perspectives

Screening has a central role in colorectal cancer (CRC) control. Different screening tests are effective in reducing CRC-specific mortality. Influence on cancer incidence depends on test sensitivity for pre-malignant lesions, ranging from almost no influence for guaiac-based fecal occult blood testing (gFOBT) to an estimated reduction of 66–90% for colonoscopy. Screening tests detect lesions indirectly in the stool [gFOBT, fecal immunochemical testing (FIT), and fecal DNA] or directly by colonic inspection [flexible sigmoidoscopy, colonoscopy, CT colonography (CTC), and capsule endoscopy]. CRC screening is cost-effective compared to no screening but no screening strategy is clearly better than the others. Stool tests are the most widely used in worldwide screening interventions. FIT will soon replace gFOBT. The use of colonoscopy as a screening test is increasing and this strategy has superseded all alternatives in the US and Germany. Despite its undisputed importance, CRC screening is under-used and participation rarely reaches 70% of target population. Strategies to increase participation include ensuring recommendation by physicians, introducing organized screening and developing new, more acceptable tests. Available evidence for DNA fecal testing, CTC, and capsule endoscopy is reviewed.

Fecal-based colorectal cancer screening among the uninsured in northern Manhattan

BACKGROUND

Colorectal cancer (CRC) screening reduces CRC mortality; however, for many reasons, uninsured individuals are less likely to utilize CRC screening tests.

PURPOSE

To compare CRC screening behaviors and outcomes with guaiac fecal occult blood testing (gFOBT) from 1998 to 2006 and fecal immunochemical testing (FIT) from 2006 to 2010 in a community-based program serving uninsured patients in northern Manhattan.

METHODS

In 2013, we conducted a retrospective record review of individuals aged ≥50 years who received fecal-based CRC screening at the Northern Manhattan Cancer Screening Partnership between 1998 and 2010. Included were those with household income ≤250% of the federal poverty level, no medical insurance coverage, and who were not up to date with CRC screening. We assessed screening positivity rate, positive predictive value, differences in the use of diagnostic colonoscopy, colonoscopic findings, and adenoma detection rates for gFOBT versus FIT.

RESULTS

In total, 7,710 patients completed CRC screenings (4,951 gFOBT and 2,759 FIT). The majority were female, Hispanic, foreign born, and young at age of first screening. Compared to gFOBT, FIT detected twice as many positive tests (3.2% vs 1.5%, p≤0.001) and had a higher adenoma detection rate (18.2 vs 11.8, p=0.002).

CONCLUSIONS

The improved positivity and adenoma detection rates with greater number of screening tests over time favor the use of FIT over gFOBT for colorectal screening among uninsured populations in northern Manhattan.

Exploring the validity of the continuum of resistance model for discriminating early from late and non-uptake of colorectal cancer screening: implications for the design of invitation and reminder letters

BACKGROUND

The continuum of resistance model contends that respondents lie at one end of a continuum and non-respondents at the other with respect to factors demonstrated to impact on screening participation.

PURPOSE

The aim of this study was to explore the validity of this model for the prediction of participation in colorectal cancer screening.

METHOD

People aged 50 to 74 years were asked to complete a survey (n = 1,250). Eligible respondents (n = 376, 30 %) were invited to complete a faecal occult blood test (FOBT). The cutoff period for the determination of participation rates was 12 weeks, with a reminder sent at 6 weeks.

RESULTS

FOBTs were returned by n = 196 people (132 within 6 weeks, 64 following a reminder). Participation was generally influenced by the same variables in both the first 6 weeks and the second 6 weeks, consistent with the continuum of resistance model. These variables were having known someone with bowel cancer and the social cognitive factor, perceptions of barriers to screening. There is a suggestion, however, that other factors may be differentially associated with early, late and non-participants.

CONCLUSION

Participation in screening appears somewhat consistent with the continuum of resistance model in that early and late participants respond to some of the same factors. This suggests that the same messages are relevant to early, late and non-screeners, but further consideration of what other factors may be influencing discrete stages of readiness to participate is necessary.

Population screening for colorectal cancer means getting FIT: the past, present, and future of colorectal cancer screening using the fecal immunochemical test for hemoglobin (FIT)

Fecal immunochemical tests for hemoglobin (FIT) are changing the manner in which colorectal cancer (CRC) is screened. Although these tests are being performed worldwide, why is this test different from its predecessors? What evidence supports its adoption? How can this evidence best be used? This review addresses these questions and provides an understanding of FIT theory and practices to expedite international efforts to implement the use of FIT in CRC screening.

Behavioural and demographic predictors of adherence to three consecutive faecal occult blood test screening opportunities: a population study

Background

Social cognitive variables are often examined for their association with initial participation in colorectal cancer screening. Few studies have examined the association of these variables with adherence to multiple screening offers i.e., rescreening. This study aimed to describe patterns of participatory behaviour after three rounds of screening using faecal immunochemical tests (FIT) and to determine social cognitive, demographic and background variables predictive of variations in adherence.

Methods

Participants were 1,540 men and women aged 50 to 75 living in South Australia who completed a behavioural survey measuring demographic (for example, age, gender) and social cognitive variables relevant to FIT screening (for example, perceived barriers, benefits, self-efficacy). The survey was followed by three, free FIT screening offers mailed on an annual basis from 2008 to 2010. Patterns of participation after three screening rounds were described as one of five screening behaviours; 1) consistent re-participation (adherent with all screening rounds), 2) consistent refusal (adherent with no screening rounds), 3) drop out (adherent with earlier but not later rounds), 4) intermittent re-participation (adherent with alternate rounds) and 5) delayed entry (adherent with later but not initial round(s)). Univariate (Chi Square and Analysis of Variance) and multivariate (Generalised Estimating Equations) analyses were conducted to determine variables predictive of each category of non-adherence (those that did not participate in every screening offer, groups 2, 3, 4 and 5) relative to consistent re-participation.

Results

Significant social cognitive predictors of non-adherence were; less self-efficacy (drop out and consistent refusal), greater perceived barriers (drop out) and lower levels of response efficacy (consistent refusal). Demographic predictors of non-adherence included; male gender (delayed entry), younger age (intermittent, delayed and consistent refusal), less frequent GP visits (intermittent re-participation) and 'ancillary only' private health insurance (drop out). Less satisfaction with screening at baseline predicted drop out, consistent refusal and delayed entry.

Conclusions

Different combinations of demographic and behavioural variables predicted different patterns of rescreening adherence. Rescreening interventions may benefit from a targeted approach that considers the different needs of the population subgroups. Satisfaction with past FOBT screening measured prior to the study screening offers was an important predictor of adherence.

Population-based colorectal cancer screening: comparison of two fecal occult blood test

BACKGROUND

The aim of screening for colorectal cancer is to improve prognosis by the detection of cancer at its early stages. In order to inform the decision on the specific test to be used in the population-based program in the Basque Autonomous Region (Spain), we compared two immunochemical fecal occult blood quantitative tests (I-FOBT).

METHODS

Residents of selected study areas, aged 50-69 years, were invited to participate in the screening. Two tests based on latex agglutination (OC-Sensor and FOB Gold) were randomly assigned to different study areas. A colonoscopy was offered to patients with a positive test result. The cut-off point used to classify a result as positive, according to manufacturer's recommendations, was 100 ng/ml for both tests.

RESULTS

The invited population included 37,999 individuals. Participation rates were 61.8% (n = 11,162) for OC-Sensor and 59.1% (n = 11,786) for FOB Gold (p = 0.008). Positive rate for OC-Sensor was 6.6% (n = 737) and 8.5% (n = 1,002) for FOB Gold (p < 0.0001). Error rates were higher for FOB gold (2.3%) than for OC-Sensor (0.2%; p < 0.0001). Predictive positive value (PPV) for total malignant and premalignant lesions was 62.4% for OC-Sensor and 58.9% for FOB Gold (p = 0.137), respectively.

CONCLUSION

OC-Sensor test appears to be superior for I-FOBT-based colorectal cancer screening, given its acceptance, ease of use, associated small number of errors and its screening accuracy. FOB Gold on the other hand, has higher rate of positive values, with more colonoscopies performed, it shows higher detection incidence rates, but involves more false positives.

Population-based colorectal cancer screening: comparison of two fecal occult blood test

BACKGROUND

The aim of screening for colorectal cancer is to improve prognosis by the detection of cancer at its early stages. In order to inform the decision on the specific test to be used in the population-based program in the Basque Autonomous Region (Spain), we compared two immunochemical fecal occult blood quantitative tests (I-FOBT).

METHODS

Residents of selected study areas, aged 50-69 years, were invited to participate in the screening. Two tests based on latex agglutination (OC-Sensor and FOB Gold) were randomly assigned to different study areas. A colonoscopy was offered to patients with a positive test result. The cut-off point used to classify a result as positive, according to manufacturer's recommendations, was 100 ng/ml for both tests.

RESULTS

The invited population included 37,999 individuals. Participation rates were 61.8% (n = 11,162) for OC-Sensor and 59.1% (n = 11,786) for FOB Gold (p = 0.008). Positive rate for OC-Sensor was 6.6% (n = 737) and 8.5% (n = 1,002) for FOB Gold (p < 0.0001). Error rates were higher for FOB gold (2.3%) than for OC-Sensor (0.2%; p < 0.0001). Predictive positive value (PPV) for total malignant and premalignant lesions was 62.4% for OC-Sensor and 58.9% for FOB Gold (p = 0.137), respectively.

CONCLUSION

OC-Sensor test appears to be superior for I-FOBT-based colorectal cancer screening, given its acceptance, ease of use, associated small number of errors and its screening accuracy. FOB Gold on the other hand, has higher rate of positive values, with more colonoscopies performed, it shows higher detection incidence rates, but involves more false positives.

Uptake and positive predictive value of fecal occult blood tests: A randomized controlled trial

OBJECTIVE

The aim of this study is to compare the uptake of three mailed high-sensitivity fecal occult blood tests (FOBTs).

METHODS

We conducted a parallel 3-arm randomized controlled trial in an integrated healthcare delivery system in Washington State. From January 2010 through February 2011, automated data were used to identify potentially eligible patients aged 50-74 due for colorectal cancer screening. Participants were mailed one of three FOBT kits (1-sample OC-Auto® fecal immunochemical test [FIT], 2-sample InSure® FIT, or 3-sample guaiac Hemoccult SENSA®), instructions, and a postage-paid return envelope. We performed a modified intent-to-treat analysis with return of any FOBT within 6 months of randomization as the primary outcome.

RESULTS

Of the 9922 people invited, 2873 returned surveys, 2263 were randomized, and 2234 were analyzed. FOBTs were returned by 1431 participants. At 6 months post-randomization, the proportions screened by any FOBT were 0.69 (95% confidence interval [CI] 0.66-0.72) for the OC-Auto arm, 0.64 (95% CI: 0.61-0.68) for the InSure arm, and 0.61 (95% CI: 0.58-0.65) for the Hemoccult SENSA arm (P<0.001 for any difference). Pairwise comparisons showed significant differences between the OC-Auto group and each of the other groups after correction for multiple comparisons.

CONCLUSION

Uptake of mailed FOBT kits varies by kit type.

Diagnostic inconsistency of faecal immunochemical tests for haemoglobin in population screening of colorectal cancer

BACKGROUND

There is currently very little data available on the consistency of quantitative and qualitative faecal immunochemical test (FIT) for colorectal cancer screening.

METHODS

A representative random population (n=1889, 40-74 year olds) in Jiashan, China was invited for FIT screening in 2012. Faecal samples were collected by a single specimen collection device and simultaneously tested by a quantitative FIT (OC-SENSOR, OC) and two qualitative FITs (FIT A and FIT B with intrinsic positive haemoglobin cut-off concentrations of 20 μg Hb/g faeces and 40 μg Hb/g faeces, respectively). The observational criteria for a positive result of the qualitative FIT were set according to the density of the colour appearing in the test strip. The results produced by the quantitative and qualitative FIT for each sample were compared. κ coefficient was used to measure consistency.

RESULTS

A total of 1368 (72.4%) individuals returned faecal samples. Both FIT A and FIT B precisely identified all faecal samples with haemoglobin concentration above 100 μg Hb/g faeces, but the overall consistency was poor for OC & FIT A (κ=0.32, 95% CI 0.20-0.44) and was moderate for OC & FIT B (κ=0.74, 95% CI 0.64-0.85). A more favourable consistency (κ=0.64, 95% CI 0.57-0.72) was achieved when a different positive criterion was employed for FIT A.

CONCLUSIONS

The diagnostic inconsistency between quantitative and qualitative FITs mainly exists in the faecal samples with low haemoglobin concentrations. Refining the criterion for a positive result may be a feasible way to improve the accuracy of qualitative FIT.

Current status of screening for colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a leading cause of cancer morbidity and mortality. A well-defined precursor lesion (adenoma) and a long preclinical course make CRC a candidate for screening. This paper reviews the current evidence for the most important tests that are widely used or under development for population-based screening.

MATERIAL AND METHODS

In this narrative review, we scrutinized all papers we have been aware of, and carried out searches in PubMed and Cochrane library for relevant literature.

RESULTS

Two screening methods have been shown to reduce CRC mortality in randomised trials: repetitive faecal occult blood testing (FOBT) reduces CRC mortality by 16%; once-only flexible sigmoidoscopy (FS) by 28%. FS screening also reduces CRC incidence (by 18%), FOBT does not. Colonoscopy screening has a potentially larger effect on CRC incidence and mortality, but randomised trials are lacking. New screening methods are on the horizon but need to be tested in large clinical trials before implementation in population screening.

CONCLUSIONS

FS screening reduces CRC incidence and CRC mortality by removal of adenomas; FOBT reduces CRC mortality by early detection of cancer. Several other tests are available, but none has been evaluated in randomised trials. Screening strategies differ considerably across countries.

Colorectal cancer screening--optimizing current strategies and new directions

The first evidence that screening for colorectal cancer (CRC) could effectively reduce mortality dates back 20 years. However, actual population screening has, in many countries, halted at the level of individual testing and discussions on differences between screening tests. With a wealth of new evidence from various community-based studies looking at test uptake, screening-programme organization and the importance of quality assurance, population screening for CRC is now moving into a new realm, promising better results in terms of reducing CRC-specific morbidity and mortality. Such a shift in the paradigm requires a change from opportunistic, individual testing towards organized population screening with comprehensive monitoring and full-programme quality assurance. To achieve this, a combination of factors--including test characteristics, uptake, screenee autonomy, costs and capacity--must be considered. Thus, evidence from randomized trials comparing different tests must be supplemented by studies of acceptance and uptake to obtain the full picture of the effectiveness (in terms of morbidity, mortality and cost) the different strategies have. In this Review, we discuss a range of screening modalities and describe the factors to be considered to achieve a truly effective population CRC screening programme.

The sensitivity and specificity of guaiac and immunochemical fecal occult blood tests for the detection of advanced colonic adenomas and cancer

PURPOSE

Fecal immunochemical tests (FITs) have been developed to address analytical problems inherent in the older guaiac-based fecal occult blood tests (g-FOBTs). Our aim was to compare the performance characteristics of one g-FOBT (Hemoccult II) and two FITs (the Hemoccult ICT and MagStream HemSp) relative to colonoscopy for the detection of colorectal cancer and significant precursor lesions. We also examined whether a 1-day collection strategy would negatively impact test diagnostic performance.

METHODS

We used a prospective observational cohort design in a Canadian population eligible for screening. All participants received colonoscopy after performing the occult blood tests.

RESULTS

One thousand seventy-five individuals were enrolled (mean age 56.3 years, 53.8 % females). Using colonoscopy as the gold standard, the sensitivity for screen-relevant neoplasm was determined for Hemoccult II (7.2, 95 % CI: 1.1-13.4), Hemoccult ICT (23.2 %: 13.2-33.1), and MagStream HemSp using 67 μg/gram stool as the cut-off (23.2 %: 13.2-33.1). The Magstream HemSp, using a cut-off threshold of 30 μg/gram stool, had the lowest specificity at 87.6 % (85.4-89.6), while the Hemoccult II had the highest at 98.8 % (98.1-99.5). Single-day stool testing reduced the false-positive rates of all tests without significantly reducing the sensitivity.

CONCLUSION

We found that FITs have a significantly increased sensitivity but reduced specificity for screen-relevant neoplasm compared to g-FOBT using colonoscopy as the gold standard. Optimal threshold levels for hemoglobin detection depend on the desired trade off between sensitivity and false-positive rate. Single-day testing with an FIT may be an option to enhance population compliance with screening.

Decision Support and the Effectiveness of Web-based Delivery and Information Tailoring for Bowel Cancer Screening: An Exploratory Study

Background

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in males and the second in females throughout the developed world. Population screening using fecal occult blood tests (FOBTs) facilitates early detection and greater chance of survival, but participation rates are low. We developed a Web-based decision tool to provide information tailored to an individual’s decision stage for CRC screening and attitude toward screening utilizing the Preventive Health Model (PHM) and Precaution Adoption Process Model (PAPM) as theoretical frameworks for screening behavior. We describe the practical steps employed in the tool’s design and the subsequent conduct of an exploratory study.

Objective

To design a decision tool for CRC screening and conduct an exploratory study among average-risk men and women to (1) test the impact of message type (tailored vs non-tailored) and message delivery modality (Web-based vs paper-based) on attitudes toward screening and screening uptake, and (2) investigate the acceptability of the decision tool and relevance of materials.

Methods

Participants (n = 100), recruited from a population sample of men and women aged 50-76 residing in urban Adelaide, Australia, were randomly assigned to a control group or one of 4 interventions: (1) Web-based and tailored information, (2) paper-based and tailored information, (3) Web-based and non-tailored (generic) information, or (4) paper-based and non-tailored information. Participation was augmented by snowball recruitment (n = 19). Questionnaires based on PHM variables were administered pre- and post-intervention. Participants were given the opportunity to request an FOBT. Following the intervention, participants discussed the acceptability of the tool.

Results

Full data were available for 87.4% (104/119) of participants. Post-intervention, perceived susceptibility scores for individuals receiving tailored information increased from mean 10.6 (SD 2.1) to mean 11.8 (SD 2.2). Scores on self-efficacy increased in the tailored group from mean 11.7 (SD 2.0) to mean 12.6 (SD 1.8). There were significant time x modality x message effects for social influence and salience and coherence, reflecting an increase in these scores for tailored Web-based participants only; social influence scores increased from mean 11.7 (SD 2.6) to mean 14.9 (SD 2.3), and salience and coherence scores increased from mean 16.0 (SD 2.2) to mean 17.7 (SD 2.1). There was no greater influence of modality or message type on movement toward a decision to screen or screening uptake, indicating that neither tailored messages nor a Web modality had superior effect. Overall, participants regarded tailored messages positively, but thought that the Web tool lacked “media richness.”

Conclusions

This exploratory study confirms that tailoring on PHM predictors of CRC screening has the potential to positively address attitudes toward screening. However, tailoring on these variables did not result in significantly increased screening uptake. Future research should consider other possible psychosocial influences. Mode of delivery did not affect outcomes, but as a delivery medium, the Web has economic and logistical advantages over paper.

Screening for colorectal cancer and advanced colorectal neoplasia in kidney transplant recipients: cross sectional prevalence and diagnostic accuracy study of faecal immunochemical testing for haemoglobin and colonoscopy

OBJECTIVE

To investigate whether screening kidney transplant recipients aged over 50 years for colorectal cancer with a faecal immunochemical test for haemoglobin might be justified, by determining the prevalence of advanced colorectal neoplasia and evaluating the diagnostic accuracy of faecal haemoglobin testing compared with colonoscopy in a population of kidney transplant recipients at otherwise average risk.

DESIGN

Cross sectional prevalence and diagnostic accuracy study with index test of faecal haemoglobin and reference standard of colonoscopy.

SETTING

Outpatient clinics in metropolitan and regional hospitals in South Australia.

PARTICIPANTS

229 kidney transplant recipients aged 50 years and over, who were at least 6 months (mean 9.0 (SD 8.4) years) post-transplant and otherwise at average risk of colorectal cancer, completed the study between June 2008 and October 2011.

INTERVENTIONS

Faecal immunochemical testing (Enterix Insure) for human haemoglobin, followed by colonoscopy with histological evaluation of retrieved samples.

MAIN OUTCOME MEASURES

Prevalence of advanced colorectal neoplasia, defined as an adenoma at least 10 mm in diameter, villous features, high grade dysplasia, or colorectal cancer; sensitivity, specificity, and predictive values of faecal haemoglobin testing for advanced neoplasia compared with colonoscopy.

RESULTS

Advanced colorectal neoplasia was found in 29 (13%, 95% confidence interval 9% to 18%) participants, including 2% (n=4) with high grade dysplasia and 2% (n=5) with colorectal cancer. Faecal testing for haemoglobin was positive in 12% (n=28); sensitivity, specificity, and positive and negative predictive values for advanced neoplasia were 31.0% (15.3% to 50.8%), 90.5% (85.6% to 94.2%), 32.1% (15.9% to 52.4%), and 90.1% (85.1% to 93.8%). Colonoscopy was well tolerated, with no significant adverse outcomes. To identify one case of advanced neoplasia, 8 (6 to 12) colonoscopies were needed.

CONCLUSIONS

Kidney transplant recipients aged over 50 years have a high prevalence of advanced colorectal neoplasia. Faecal haemoglobin screening for colorectal neoplasia has similar performance characteristics in transplant recipients to those reported in general population studies, with poor sensitivity but reasonable specificity. Surveillance colonoscopy might be a more appropriate approach in this population.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12608000154303.

Psychosocial variables associated with colorectal cancer screening in South Australia

BACKGROUND

Population screening reduces mortality from colorectal cancer, yet factors associated with uptake of screening are incompletely understood.

PURPOSE

The purpose of the study was to determine demographic and psychosocial factors associated with participation in faecal occult blood test (FOBT)-based colorectal cancer (CRC) screening in an average risk community programme in Adelaide, South Australia.

METHOD

A questionnaire consistent with the Preventive Health Model was used to determine demographic and psychosocial differences between previous FOBT-based screening participants (n = 413, response rate 93.2%) and non-participants (n = 481, response rate 47.9%). Results were analysed by univariate and multivariate generalised linear modelling, and factors associated with participation were identified.

RESULTS

Factor analysis of psychosocial items revealed an optimal three-factor solution (knowledge, faecal aversion, belief in the value of screening). Following multivariate analyses, two psychosocial and two demographic factors remained as predictors of FOBT screening behaviour: (1) items related to faecal aversion (Aversion), relative risk (RR) = 0.61, CI = 0.55-0.69, (2) perceptions about the value of screening (Value), RR = 1.45, CI = 1.13-1.85, (3) age band 65-69 (Age, five age bands, relative to age 50-54), RR = 1.43, CI = 1.16-1.76 and FOBT type (Test; three tests, Hemoccult, FlexSure, InSure randomly assigned, relative to Hemoccult: FlexSure: RR = 1.41, CI = 1.17-1.71, InSure: RR = 1.76, CI = 1.47-2.11.

CONCLUSIONS

The psychosocial factors associated with non-participation in FOBT-based CRC screening are amenable to interventions designed to improve participation. The small relative risks values associated with each predictor, however, raise the possibility that additional factors are likely to influence screening participation.

Factors affecting compliance in faecal occult blood testing: a cluster randomized study of the faecal immunochemical test versus the guaiac faecal occult test

OBJECTIVE

To compare the uptake of faecal immunochemical occult blood test (FIT) with guaiac faecal occult blood test (gFOBT) in a screening programme, with specific attention to the demographic and socioeconomic factors that might affect test uptake.

SETTING

The Clalit Health Service screening programme, Israel.

METHODS

Average-risk individuals aged 50-75 years were randomized into a FIT arm or gFOBT arm using a programme based on the socioeconomic status (SES) of their primary care clinics. G-FOBT was performed with Hemoccult SENSA™ (3 evacuations) and FIT with the OC- MICRO(TM) (3 evacuations, refrigerating mandated). The GLIMMIX model was used.

RESULTS

There were 5,464 and 10,668 eligible participants in the FIT and gFOBT arms respectively. Compliance in taking the kits was better (but not statistically significantly better) with gFOBT (37.8% vs. 29.3%; odds ratio [OR] 1.43 [95% CI 0.73-2.80]; P = 0.227). Kit return was higher in the FIT arm (65.0% vs. 78.9%; OR 0.45 [95% CI 0.24-0.83], P = 0.021). Overall test uptake was affected by age, gender, being immigrant and SES (determined by whether or not the participant paid national insurance tax, and the SES of the primary care clinic). The overall uptake of gFOBT and FIT was comparable (OR 0.996 [95% CI 0.46-2.17], P = 0.99).

CONCLUSIONS

Overall compliance for test uptake was comparable between the two methods despite the more demanding procedure in the FIT arm. Sociodemographic parameters were the major determinants of compliance. An educational programme, with emphasis on the sociodemographic characteristics of the target population, should be instigated.

Feasibility and efficacy of pairing fecal immunochemical testing with mammography for increasing colorectal cancer screening among uninsured Latinas in northern Manhattan

OBJECTIVES

We evaluated the feasibility and efficacy of a program to promote colorectal cancer screening (CRC) among uninsured Latinas receiving mammography through a cancer screening clinic in northern Manhattan.

METHODS

Between August 2009 and March 2010, unscreened, average CRC risk, uninsured Latinas, aged 50-64 years, undergoing mammography received a screening recommendation, education, and fecal immunochemical test (FIT). Socio-demographic information and level of acculturation was collected. Screening compliance was assessed.

RESULTS

Of 651 Latinas evaluated, 210 were eligible and, of these, 94% (n=197) consented to participate; 441 were excluded because they were up-to-date with CRC screening (n=130), < 50 (n=285) or >64 (n=26) years of age. After intervention, 177 (90%) completed FIT. Within 2 weeks, 87% completed the FIT, and 69% did so with no reminder calls. Acculturation was significantly lower among screeners (p=0.014). Compared with non-screeners, screeners were more likely to be foreign-born (p=0.009), to speak only Spanish (p=0.043), and to prefer to read (p=0.037), and think (p=0.015) in Spanish.

CONCLUSION

This study suggests that pairing CRC education and screening with mammography is both feasible and efficacious.

Cost-effectiveness of a mailed educational reminder to increase colorectal cancer screening

BACKGROUND

Colorectal cancer (CRC) screening rates are low in many areas and cost-effective interventions to promote CRC screening are needed. Recently in a randomized controlled trial, a mailed educational reminder increased CRC screening rates by 16.2% among U.S. Veterans. The aim of our study was to assess the costs and cost-effectiveness of a mailed educational reminder on fecal occult blood test (FOBT) adherence.

METHODS

In a blinded, randomized, controlled trial, 769 patients were randomly assigned to the usual care group (FOBT alone, n = 382) or the intervention group (FOBT plus a mailed reminder, n = 387). Ten days after picking up the FOBT cards, a 1-page reminder with information related to CRC screening was mailed to the intervention group. Primary outcome was number of returned FOBT cards after 6 months. The costs and incremental cost-effectiveness ratio (ICER) of the intervention were assessed and calculated respectively. Sensitivity analyses were based on varying costs of labor and supplies.

RESULTS

At 6 months after card distribution, 64.6% patients in the intervention group returned FOBT cards compared with 48.4% in the control group (P < 0.001). The total cost of the intervention was $962 or $2.49 per patient, and the ICER was $15 per additional person screened for CRC. Sensitivity analysis based on a 10% cost variation was $13.50 to $16.50 per additional patient screened for CRC.

CONCLUSIONS

A simple mailed educational reminder increases FOBT card return rate at a cost many health care systems can afford. Compared to other patient-directed interventions (telephone, letters from physicians, mailed reminders) for CRC screening, our intervention was more effective and cost-effective.