Ozbay, A. Burak

Background: Fecal immunochemical tests (FITs), fecal occult blood tests (FOBTs), and multitarget stool DNA (mt-sDNA) tests are convenient, noninvasive colorectal cancer (CRC) screening strategies. However, delays in or failure to complete follow-up colonoscopy (FU-CY) after a positive noninvasive test are associated with higher CRC incidence, complications, and mortality. We sought to evaluate FU-CY rates, time to colonoscopy, and compliance predictors. Patients and Methods: This retrospective cohort study linked 2 data sources: Komodo Health Data with Exact Sciences Laboratories. Data were collected from January 2016 to June 2023 and analyzed in 2024. Study participants (ages 45–75 years) were individuals with positive stool-based CRC screening tests (FIT, guaiac-based FOBT, or mt-sDNA tests). FU-CY compliance was assessed at 30-day intervals up to 365 days, and logistic regression was used to identify predictors of FU-CY. Results: Among 362,646 participants, colonoscopy compliance was 77.1% for mt-sDNA and 45.1% for FIT/FOBT ( P <.001). Overall FU-CY compliance was lowest among Asian and Black populations, but was significantly higher in these subgroups for mt-sDNA versus FIT (Asian: 74.2% vs 41.1%; Black: 71.3% vs 44.6%). The strongest predictor of compliance was use of mt-sDNA (odds ratio, 3.98; P <.001). More than half of participants across all race groups who completed FU-CY after mt-sDNA did so within the first 120 days, whereas none of the FIT/FOBT racial subgroups reached 50% completion within 365 days. Conclusions: Timely completion of colonoscopy after a noninvasive test is critical, as failure to undergo colonoscopy or delays in completion are associated with increased CRC incidence and more advanced-stage disease. These findings demonstrate that mt-sDNA use may help close CRC screening disparity gaps compared with FIT testing. FU-CY adherence is higher, and time to colonoscopy is shorter following a positive mt-sDNA test versus FIT across all racial and ethnic subgroups.

ABSTRACT Background Several colorectal cancer (CRC) screening modalities are guideline-recommended in the United States, yet they vary considerably in screening interval and real-world adherence. As a result, single-round test performance may not reflect cumulative effectiveness over time. This study compared the 10-year longitudinal outcomes of two CRC screening strategies— triennial next-generation multitarget stool DNA testing (ng mt-sDNA) and decennial screening colonoscopy. Methods This study used the validated, microsimulation-based Colorectal Cancer and Adenoma Incidence and Mortality (CRC-AIM) model to estimate 10-year cumulative outcomes for two guideline-recommended screening strategies: triennial ng mt-sDNA and decennial colonoscopy. Model inputs included test-specific performance and real-world adherence. Outcomes included CRC and precancerous lesions detected, CRC mortality reductions, and life-years gained (LYG). Sensitivity analyses examined the effects of varying both screening adherence and follow-up colonoscopy adherence. Results Over 10 years per 1,000 individuals offered screening, the ng mt-sDNA screening test detected 13% more precancerous lesions and 11% more CRC cases than colonoscopy, with a greater proportion of CRCs identified through screening rather than symptomatic detection. ng mt-sDNA resulted in greater CRC mortality reduction (33% vs 20%) and 62% more life-years gained, with consistent findings across sensitivity analyses. Conclusions With real-world adherence, screening with triennial ng mt-sDNA demonstrates superior cumulative effectiveness compared with decennial colonoscopy, driven by higher adherence and favorable longitudinal performance. These findings support the expanded use of noninvasive stool-based screening to reduce CRC mortality and alleviate capacity constraints associated with colonoscopy-based screening. Broader adoption of ng mt-sDNA may enhance population-level CRC prevention by increasing participation and improving early detection across the screening eligible population. Plain language summary Colorectal cancer screening tests are recommended at different time intervals and completed at different adherence rates in clinical practice. The analysis used a validated simulation model to compare 10-year outcomes of triennial next-generation multi-target stool DNA test (ng mt-sDNA) with a single colonoscopy, accounting for real-world screening and follow-up colonoscopy adherence. Our findings indicate that repeated ng mt-sDNA provides greater cumulative screening effectiveness than colonoscopy over a 10-year period.

Abstract Background Recommended noninvasive strategies for average-risk colorectal cancer (CRC) screening include multitarget stool DNA and fecal immunochemical test from ages 45 to 75 years. With new clinical trials, performance data for next-generation multitarget stool DNA, multitarget stool RNA, and blood-based screening tests are now available. This decision analytical model study evaluated the estimated benefit-to-burden ratio by means of efficient frontiers for noninvasive established and emerging CRC screening strategies. Methods Outcomes were estimated using the Colorectal Cancer and Adenoma Incidence and Mortality microsimulation model for average-risk individuals in the United States. Screening strategies were next-generation multitarget stool DNA (an updated marker panel), fecal immunochemical tests, multitarget stool RNA, or blood-based tests every 1-3 years, over various age ranges. Test performance inputs were derived from recent large clinical trials. A strategy was deemed efficient if no other strategy provided more life-years gained with equivalent or fewer lifetime colonoscopies and near-efficient if within 3 days of life-years gained of the efficient frontier. Results All modeled screening strategies resulted in life-years gained vs no screening. No strategy using blood-based tests was efficient or near-efficient. Overall, 10 strategies were efficient (6 next-generation multitarget stool DNA and 4 fecal immunochemical tests), including 2 strategies among those ages 45-75 years (biennial and triennial next-generation multitarget stool DNA). Overall, 22 strategies were near-efficient, including 4 strategies among those ages 45-75 years (annual, biennial, or triennial fecal immunochemical test; annual next-generation multitarget stool DNA). Conclusion Based on this modeling study, next-generation multitarget stool DNA was the only noninvasive screening test at guideline-endorsed interval and age-recommended ranges that was deemed efficient. Blood-based and multitarget stool RNA strategies were deemed not efficient for primary screening.

Background Colorectal cancer (CRC) is the fourth most frequently diagnosed cancer and the second leading cause of cancer-related deaths in the United States. Screening can prevent CRC by detecting advanced precancerous lesions. Adherence to screening is crucial in reducing CRC disease burden; however, there is limited research on the impact of digital outreach screening uptake and adherence. Objective This study evaluated the impact of different digital outreach channels on patient adherence to CRC screening with a multi-target stool DNA (mt-sDNA) test in a real-world setting. Methods Patients were individuals aged 45 to 85 years with a valid mt-sDNA test order from Exact Sciences Laboratories, LLC (Jan. 1, 2023–Sept. 23, 2023). All patients received letters and phone calls; some received short message service (SMS), email, or both. Adherence and time to test return were compared across digital outreach categories stratified by patient characteristics. Multivariable regression evaluated the association of digital outreach methods with adherence and time to test return. Results Among 2 425 308 patients (43.5% between 50 and 64 years, 58.2% female), digital SMS only (62.7%) was the most common outreach method. Overall adherence was 70.1%, with highest adherence in the digital SMS-plus-email group (72.9%). Mean time to test return from shipment of mt-sDNA kit to receipt of valid test was 25.8 days. In adjusted analyses, patients receiving digital SMS plus email had the highest odds of test return (odds ratio, 1.75; 95% confidence interval [CI], 1.73-1.78; P <.001) and had return times 8.7% shorter than the no-digital-outreach group (95% CI, 8.2-9.2; P <.001). Discussion Among nationally insured individuals within the recommended age range for CRC screening, overall adherence to the mt-sDNA test was in the 70s, with the highest rates in the digital (SMS and email) outreach group and the lowest in the no-digital-outreach group. Conclusions These findings highlight the importance of multichannel navigation in facilitating completion of CRC screening with the mt-sDNA test.

Objectives: To describe member adherence to a mail-based, health insurer-sponsored gap closure program for colorectal cancer (CRC) screening using multi-target stool DNA (mt-sDNA; Cologuard ® ) tests. Methods: Combined patient data from Exact Sciences Laboratories LLC and data from mass-mailed mt-sDNA orders placed by a large Medicare Advantage Insurance Plan were analyzed (03/01/2023-06/30/2023). Adherence and time to test return were the primary and secondary outcomes, respectively. Their association with patient characteristics was evaluated using multivariable regression. Results: Among the 3201 member-patients included (86.6% aged 65-75 years; 58.7% female), adherence rate was 49.4%, and mean time to test return was 25.5 days. After multivariable adjustment, the odds of test return were significantly higher among 65- to 75-year-olds (odds ratio [OR] = 1.59 relative to 45- to 64-year-olds), those living in small towns (OR = 1.43 relative to metropolitan-located individuals), and with digital outreach via both SMS and email (OR = 4.31 relative to no digital outreach). Time to test return was shorter in 65- to 75-year-olds than in 45- to 64-year-olds and was not associated with other patient characteristics. Conclusions: Mass-mailed mt-sDNA tests for CRC screening were associated with an overall adherence rate of about 50% in this Medicare Advantage population, with higher likelihood of test return among patients receiving digital outreach.

Abstract Introduction: Blood-based tests represent a compelling option for early detection and management of cancers and other chronic diseases. While blood-based tests may offer potential to increase patient engagement, the assumption of greater adherence in clinical practice requires further evaluation. This systematic review aimed to evaluate the real-world adherence to established blood-based tests for commonly recommended screening indications, to better inform expectations for proposed application to average-risk colorectal cancer (CRC) screening. Methods: A systematic search of PubMed, Embase, and citations was performed to identify literature published from 2010 to 2023. Studies examined adherence to routine blood-based laboratory tests with a Grade A or B recommendation per the United States Preventive Services Task Force (USPSTF) for diabetes, dyslipidemia, human immunodeficiency virus (HIV), and hepatitis C virus (HCV) in an average-risk patient population were included. In addition, prostate-specific antigen (PSA) testing adherence for prostate cancer screening (Grade-C USPSTF recommendation), the only commonly accessible blood-based single-cancer screening test for average-risk adults, was also included. Studies without venipuncture-derived blood were excluded. Results: Of 53,067 articles screened, 69 were included in the analysis. Overall, adherence rates of blood-based tests were highly variable, with median values (interquartile range, IQR) of 66.3% (11.8%), 67.8% (18.0%), 34% (28.7%), and 36.8% (30%) for diabetes, dyslipidemia, HCV, and HIV, respectively. PSA testing adherence was 37.2% (18.4%). Beyond disease type, adherence varied by study design, data source, patient characteristics, clinical setting, and study country. Information and selection bias were the most common risks of bias. Conclusions: Based on data from this comprehensive systematic review, real-world adherence to currently recommended, blood-based screening strategies is suboptimal. Future research is needed to identify the extent to which these data are generalizable to blood-based CRC screening, and to determine if/how this candidate strategy would impact clinical, economic, and health equity outcomes. Citation Format: Quang A. Le, Takako Kiener, Heather A. Johnson, Rukaiyya S. Khan, Joyce Kong, Kevin H. Li, Gina Thompson, A. Burak Ozbay, Mallik Greene, Paul J. Limburg, A. Mark Fendrick, John B. Kisiel, Derek W. Ebner. Systematic review of real-world adherence to blood-based laboratory tests for average-risk disease screening: potential implications for emerging colorectal cancer screening modalities [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr A027.