Ozbay, A. Burak

Abstract Colorectal cancer is the second leading cause of cancer-related mortality in adults in the United States. Despite compelling evidence of improved outcomes in colorectal cancer, screening rates are not optimal. This study aimed to characterize colorectal cancer screening trends over the last two decades and assess the impact of various screening modalities on overall colorectal cancer screening rates. Using National Health Interview Survey data from 2005 to 2021, we examined colorectal cancer screening [colonoscopy, multitarget stool DNA (mt-sDNA), fecal occult blood test (FOBT)/fecal immunochemical test, sigmoidoscopy, CT colonography] rates among adults ages 50–75 years (n = 85,571). A pseudo-time-series cross-sectional (pseudo-TSCS) analysis was conducted including a random effects generalized least squares regression model to estimate the relative impact of each modality on changes in colorectal cancer screening rates. Among 50 to 75 year olds, the estimated colorectal cancer screening rate increased from 47.7% in 2005 to 69.9% in 2021, with the largest increase between 2005 and 2010 (47.7%–60.7%). Rates subsequently plateaued until 2015 but increased from 63.5% in 2015 to 69.9% in 2018. This was primarily driven by the increased use of mt-sDNA (2.5% in 2018 to 6.6% in 2021). Pseudo-TSCS analysis results showed that mt-sDNA contributed substantially to the increase in overall screening rates (77.3%; P < 0.0001) between 2018 and 2021. While colorectal cancer screening rates increased from 2005 to 2021, they remain below the 80% goal. The introduction of mt-sDNA, a noninvasive screening test may have improved overall rates. Sustained efforts are required to further increase screening rates to improve patient outcomes and offering a range of screening options is likely to contribute to achieving this goal. Prevention Relevance: This retrospective study highlights the importance of convenient stool-based colorectal cancer screening options to achieve the national goal of 80% for overall colorectal cancer screening rates. Empowering screening-eligible individuals with a choice for their colorectal cancer screening tests is imperative.

67 Background: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality among men and women combined in the United States (US). Although the national screening rate has increased over the years, it remains below the target of 80% recommended by the National Colorectal Cancer Roundtable for improved CRC outcomes. In most recent years, and particularly during COVID-19, screening-eligible individuals preferred at-home, non-invasive screening options over invasive tests such as colonoscopy due to convenience and accessibility. The objective of this study was to understand the CRC screening trends over the last two decades, and the impact of various screening modalities on the overall CRC screening rate. Methods: Using National Health Interview Survey (NHIS) data from 2005 onwards, we examined CRC screening (colonoscopy, mt-sDNA, FIT/FOBT, and sigmoidoscopy) rates among adults aged 50-75 years. A pseudo-time-series cross-sectional (pseudo TSCS) analysis was conducted including random effects Generalized Least Square (GLS) regression model to estimate the relative impact of each modality on the overall increase in CRC rates from 2018 to 2021. Results: Among 50-75 years old individuals, the estimated CRC screening use increased by 32% from 2005 to 2021 (47.7% to 69.9%). Between 2018 to 2021, the rates increased from 64% to 70%, driven largely by increased use of mt-sDNA, a 62.1% increase from 2018 to 2021 (2.5% to 6.6%). During this time period, colonoscopy utilization increased by 4.4% (61.2% to 64.0%), while FOBT/FIT utilization increased by 3.6% (5.3% to 5.5%). A pseudo-TSCS analysis showed that mt-sDNA contributed substantially to the overall CRC screening rate increase during years 2018-2021 (77.3%; p < 0.0001). Conclusions: While CRC screening rates are increasing, they remain below the national goal of 80%. Mt-sDNA as a home-based, non-invasive screening, recommended at a 3-year interval, has been leveraged to improve overall CRC screening rates, particularly to address the screening backlog created during the COVID-19 pandemic. A collaborative approach between healthcare providers and screening-eligible individuals is needed to empower patients with choice for their CRC screening modality to achieve the national goal.

The Centers for Medicare & Medicaid Services (CMS) recommend covering blood-based tests meeting proposed minimum performance thresholds for colorectal cancer (CRC) screening. Outcomes were compared between currently available stool-based screening tests and a hypothetical blood-based test meeting CMS minimum thresholds. Using the Colorectal Cancer and Adenoma Incidence and Mortality Microsimulation Model (CRC-AIM), outcomes were simulated for average-risk individuals screened between ages 45 and 75 years with triennial multitarget stool DNA (mt-sDNA), annual fecal immunochemical test (FIT), and annual fecal occult blood test (FOBT). Per CMS guidance, blood-based CRC screening was modeled triennially, with 74% CRC sensitivity and 90% specificity. Although not specified by CMS, adenoma sensitivity was set between 10% and 20%. Published adenoma and CRC sensitivity and specificity were used for stool-based tests. Adherence was set at (1) 100%, (2) 30%–70%, in 10% increments, and (3) real-world rates for stool-based tests (mt-sDNA = 65.6%; FIT = 42.6%; FOBT = 34.4%). Assuming perfect adherence, a blood-based test produced ≥19 lower life-years gained (LYG) than stool-based strategies. At the best-case scenario for blood-based tests (100% adherence and 20% adenoma sensitivity), mt-sDNA at real-world adherence achieved more LYG (287.2 vs. 297.1, respectively) with 14% fewer colonoscopies. At 100% blood-based test adherence and real-world mt-sDNA and FIT adherence, the blood-based test would require advanced adenoma sensitivity of 30% to reach the LYG of mt-sDNA (297.1) and ∼15% sensitivity to reach the LYG of FIT (258.9). This model suggests that blood-based tests with CMS minimally acceptable CRC sensitivity and low advanced adenoma sensitivity will frequently yield inferior outcomes to stool-based testing across a wide range of adherence assumptions.

10580 Background: Blood-based tests are an emerging option for non-invasive colorectal cancer (CRC) screening for which the Centers for Medicare & Medicaid Services (CMS) has proposed coverage every 3 years for average-risk individuals. Analyses with the CRC-AIM microsimulation model demonstrated that triennial screening with blood-based tests with CMS minimum performance often yields inferior outcomes to stool-based CRC screening (fecal immunochemical test [FIT] and multi-target stool DNA [mt-sDNA]). CRC-AIM was used to explore the impact of blood-based screening intervals, using reported performance characteristics from the ECLIPSE study (Guardant Health, Inc.)1, on estimated clinical outcomes vs FIT and mt-sDNA screening. Methods: Outcomes were simulated for average-risk individuals screened between ages 45-75 years. Intervals were set at 1, 2, or 3 years for blood-based, 3 years for mt-sDNA and annually for FIT screening. The blood-based test was modeled at 83% CRC sensitivity, 13% advanced adenoma sensitivity, and 90% specificity. Perfect adherence (100%) was modeled for blood-based tests and real-world adherence rates used for CRC initial screening tests (mt-sDNA=65.6%; FIT=42.6%) and follow-up colonoscopy (mt-sDNA=72.1%; FIT=46.0%). Primary outcomes were life-years gained (LYG) and colonoscopies (COL) per 1000 individuals for blood-based screening compared to mt-sDNA and FIT. As a secondary analysis, estimates were generated with perfect (100%) adherence assumed for initial screening and follow-up colonoscopy for mt-sDNA and FIT as well. Results: Blood-based testing at a 3-year interval with 100% adherence led to 11% fewer LYG than mt-sDNA at RWE adherence (240 vs 270, respectively), and 9% more COL (1402/1000 vs 1288/1000). Meanwhile, blood-based testing at a 1-year interval and perfect adherence (best case scenario) resulted in the lowest LYG per COL ratio across all scenarios (16% more LYG and 87% more COL compared to mt-sDNA at RWE adherence). Blood-based test results showed similar trends when compared to FIT. Conclusions: Outcomes for blood-based screening every 3 years based on reported test performance characteristics and unrealistic perfect adherence demonstrate fewer LYG as compared to either mt-sDNA or FIT. When compared to real-world adherence for mt-sDNA and FIT, blood-based tests with 1- and 2-year intervals and perfect adherence had higher LYG with the tradeoff of a greater number of diagnostic colonoscopies. [Table: see text]

e18911 Background: Stool-based colorectal cancer (CRC) screening with the multi-target stool DNA (mt-sDNA) test is a guideline endorsed strategy for average-risk individuals age ≥45 years and provides a reference for value-based pricing (VBP); maximum price at which a willingness-to-pay threshold is reached. Blood-based tests (BT) are an emerging screening option. Using recent reported BT performance data from the ECLIPSE study (Guardant Health, Inc.)1, the potential VBP of BT compared with multi-target stool DNA (mt-sDNA) was analyzed. Methods: Using the validated CRC-AIM model, we simulated a cohort of 2 million average-risk individuals who received screening with BT at 1, 2, or 3-year intervals or triennial mt-sDNA between the ages of 45-75 years. For BT, CRC sensitivity, advanced adenoma sensitivity, and specificity were based on reported clinical trial data (83%, 13%, and 90%, respectively). Adherence assumptions for BT and mt-sDNA screening were modeled at perfect (100%) or real-world mt-sDNA adherence (RWE). Key outcomes were life-years gained (LYG) per 1000 individuals vs no screening, and VBP of BT vs mt-sDNA ($895 vs $508) was assessed at a willingness-to-pay (WTP) threshold of $50,000 per quality-adjusted life-year. Results: The triennial mt-sDNA was more effective and less costly vs BT at all intervals with both perfect and RWE adherence at the current price. Compared with mt-sDNA screening, LYG of screening with BT was lower (320 vs. 241-314) and the VBP should be at most $49 and $11 and no-cost at the 1-, 2-, and 3-year intervals, respectively (Table), when perfect adherence is assumed. With RWE adherence, the LYG with mt-sDNA was 306 compared to 229-284 with BT across all intervals. To be comparable to RWE triennial mt-sDNA screening, the maximum VBP for BT would need to be $13 at the 1-year interval and no cost for 2- and 3-year interval. Conclusions: Compared to annual, biannual, and triennial BT, triennial mt-sDNA was more effective at all intervals and 44% to 102% less costly. The maximum price of BT should not exceed $49 to be considered a cost-effective option compared to mt-sDNA when WTP is 50,000. [Table: see text]

6642 Background: Although follow up colonoscopy (COL) after a positive stool-based colorectal cancer (CRC) screening test is necessary to complete the CRC screening process, follow-up COL rates remain suboptimal, especially among underserved populations. As of January 2023, federal policies require commercial insurers and Medicare to eliminate out of pocket costs for follow-up COL. To estimate the implications of this policy change, we compared the clinical and fiscal outcomes for a simulated cohort receiving a follow-up COL after a non-invasive CRC test ($0 cost sharing), compared to the same cohort not completing follow-up COL (status quo). Methods: Using the validated CRC-AIM model, we simulated a cohort of 6 million average-risk individuals who received mt-sDNA (commercial patients at age 45 and Medicare patients at age 65) and further analyzed only the population with positive mt-sDNA. Life-years gained, CRC incidence, CRC-related mortality and total costs of care (inclusive of CRC screening and treatment) were calculated for a cohort that underwent follow-up COL and compared these outcomes to that same cohort that did not complete follow-up COL. The cost of follow-up COL was assumed to be $1,576 for Medicare and $3,086 for commercially insured patients ($0 out of pocket costs for all). Results: Patients undergoing follow-up COL after a positive mt-sDNA experienced more life-years (83 per 1,000 commercially insured patients and 80 per 1,000 Medicare beneficiaries) compared to those who did not undergo follow-up COL. The follow-up COL resulted in reductions in CRC incidence and CRC mortality by 14% and 16% for commercial and 19% and 23% for Medicare beneficiaries, respectively. Compared to those patients with a mt-sDNA positive test result and did not complete follow-up COL, the total cost per patient for those receiving follow-up COL was $3,339 less for commercially insured ($15,690 – no follow up vs. $12,351 – follow up) and $4,382 less for Medicare beneficiaries ($19,337 – no follow up vs. $14,955 – follow up). Total spending for patients receiving follow-up COL was cost-saving when compared to no follow-up as long as the COL costs were less than $6,269 for commercial plans and $5,753 for Medicare. Conclusions: Completing a follow-up COL after a positive mt-sDNA screening saves lives, enhances equity, and lowers total expenditures. Thus, health care stakeholders should invest in efforts to identify and reduce barriers that ultimately lead to an increase uptake of this potentially lifesaving and cost-reducing intervention.

Background: The effectiveness of ultrasound-based surveillance for HCC in patients with cirrhosis is limited by suboptimal sensitivity for early tumor detection and poor adherence. Emerging blood-based biomarkers have been proposed as an alternative surveillance strategy. We aimed to evaluate the comparative effectiveness of a multitarget HCC blood test (mt-HBT)—with and without improved adherence—against ultrasound-based HCC surveillance. Methods: We developed a Markov-based mathematical model that simulated a virtual trial in patients with compensated cirrhosis comparing potential surveillance strategies: biannual surveillance using ultrasound, ultrasound plus AFP, and mt-HBT with or without improved adherence (+10% increase). We used published data to inform underlying liver disease progression rates, HCC tumor growth patterns, performance characteristics of surveillance modalities, and efficacy of treatments. Primary outcomes of interest were the number of early-stage HCCs detected and life years gained. Results: Per 100,000 patients with cirrhosis, mt-HBT detected 1680 more early-stage HCCs than ultrasound alone and 350 more early-stage HCCs than ultrasound + AFP, yielding an additional 5720 and 1000 life years, respectively. mt-HBT with improved adherence detected 2200 more early-stage HCCs than ultrasound and 880 more early-stage HCCs than ultrasound + AFP, yielding an additional 8140 and 3420 life years, respectively. The number of screening tests needed to detect one HCC case was 139 with ultrasound, 122 with ultrasound + AFP, 119 with mt-HBT, and 124 with mt-HBT with improved adherence. Conclusions: mt-HBT is a promising alternative to ultrasound-based HCC surveillance, particularly given anticipated improved adherence with blood-based biomarkers could increase HCC surveillance effectiveness.