Income differences in time to colon cancer diagnosis.

INTRODUCTION: People with low income have worse outcomes throughout the cancer care continuum; however, little is known about income and the diagnostic interval. We described diagnostic pathways by neighborhood income and investigated the association between income and the diagnostic interval. METHODS: This was a retrospective cohort study of colon cancer patients diagnosed 2007-2019 in Ontario using routinely collected data. The diagnostic interval was defined as the number of days from the first colon cancer encounter to diagnosis. Asymptomatic pathways were defined as first encounter with a colonoscopy or guaiac fecal occult blood test not occurring in the emergency department and were examined separately from symptomatic pathways. Quantile regression was used to determine the association between neighborhood income quintile and the conditional 50th and 90th percentile diagnostic interval controlling for age, sex, rural residence, and year of diagnosis. RESULTS: A total of 64,303 colon cancer patients were included. Patients residing in the lowest income neighborhoods were more likely to be diagnosed through symptomatic pathways and in the emergency department. Living in low-income neighborhoods was associated with longer 50th and 90th-percentile symptomatic diagnostic intervals compared to patients living in the highest income neighborhoods. For example, the 90th percentile diagnostic interval was 15 days (95% CI 6-23) longer in patients living in the lowest income neighborhoods compared to the highest. CONCLUSION: These findings reveal income inequities during the diagnostic phase of colon cancer. Future work should determine pathways to reducing inequalities along the diagnostic interval and evaluate screening and diagnostic assessment programs from an equity perspective.

Cost-effectiveness Analysis of Colorectal Cancer Screening Strategies Using Active Learning and Monte Carlo Simulation.

INTRODUCTION: Detection of colorectal cancer (CRC) in the early stages through available screening tests increases the patient's survival chances. Multimodal screening policies can benefit patients by providing more diverse screening options and balancing the risks and benefits of screening tests. We investigate the cost-effectiveness of a wide variety of multimodal CRC screening policies. METHODS: We developed a Monte Carlo simulation framework to model CRC dynamics. We proposed an innovative calibration process using machine learning models to estimate age- and size-specific adenomatous polyps' progression and regression rates. The proposed approach significantly expedites the model parameter space search. RESULTS: Two multimodal proposed policies (i.e., 1] colonoscopy at 50 y and fecal occult blood test annually between 60 and 75 y and 2] colonoscopy at 50 and 60 y and fecal immunochemical test annually between 70 and 75 y) are identified as efficient frontier policies. Both policies are cost-effective at a willingness to pay of $50,000. Sensitivity analyses were performed to assess the sensitivity of results to a change in screening test costs as well as adherence behavior. The sensitivity analysis results suggest that the proposed policies are mostly robust to the considered changes in screening test costs, as there is a significant overlap between the efficient frontier policies of the baseline and the sensitivity analysis cases. However, the efficient frontier policies were more sensitive to changes in adherence behavior. CONCLUSION: Generally, combining stool-based tests with visual tests will benefit patients with higher life expectancy and a lower expected cost compared with unimodal screening policies. Colonoscopy at younger ages (when the colonoscopy complication risk is lower) and stool-based tests at older ages are shown to be more effective. HIGHLIGHTS: We propose a detailed Markov model to capture the colorectal cancer (CRC) dynamics. The proposed Markov model presents the detailed dynamics of adenomas progression to CRC.We use more than 44,000 colonoscopy reports and available data in the literature to calibrate the proposed Markov model using an innovative approach that leverages machine learning models to expedite the calibration process.We investigate the cost-effectiveness of a wide variety of multimodal CRC screening policies and compare their performances with the current in-practice policies.

Costs in Colectomy Episodes of Care: Opportunities to Prevent Emergency Operations and Decrease Costs.

INTRODUCTION: Payment structured around Episodes of Care is a method for incentivizing decreased care utilization after major procedures. We examined Major Bowel Episodes of Care (MB-EoC)-the focus among general surgery procedures-within a large health system to determine the contribution of emergency bowel surgery to higher costs of care. METHODS: Adult MB-EoC cases from July 2018 to June 2021 were reviewed for 90-d costs, examining patient age, insurance, diagnosis, cost of care, and contributors to cost. For patients aged ≥45 y who had nonelective care for colon cancer, incidence of prior screening colonoscopy was examined. RESULTS: We identified 1292 colectomy cases. Mean age was 65 y. Of these patients, 90% had Medicare/commercial insurance. Colon cancer comprised 41% of primary diagnoses. Twenty-eight percent of cases were nonelective, more likely to have Medicaid/underinsured (21% versus 7%, P < 0.001), and had higher utilization of postdischarge cost-drivers. Ninety-day EoC per case cost was 66% higher for emergent versus elective cases. Of eligible emergency cancer cases, 43% (40/93) had undergone prior colonoscopy within 10 y. For patients with colon cancer, 90-d EoC per case was 39% higher for emergent versus elective cases. CONCLUSIONS: Emergency MB-EoC cases disproportionally contribute to higher 90-d care utilization and costs. Efforts to increase screening colonoscopy in appropriate populations may have a substantial impact on MB-EoC costs.

Quantified trends in provider reimbursement and utilization volume in colorectal cancer screenings: analysis of Medicare claims from 2000 to 2019.

AIM: Colorectal cancer (CRC) screening rates in the United States remain persistently below guideline targets, partly due to suboptimal patient utilization and provider reimbursement. To guide long-term national utilization estimates and set reasonable screening adherence targets, this study aimed to quantify trends in utilization of and reimbursement for CRC screenings using Medicare claims. METHOD: Inflation-adjusted reimbursements and utilization volume associated with each CRC screening code were abstracted from Medicare claims between 2000 and 2019. Screenings, screenings/100 000 enrolees and reimbursement/screening were analysed with linear regression and compared with the equality of slopes tests. Average reimbursement per screening was compared using analysis of variance with Dunnett's T3 multiple comparisons test. RESULTS: The growth rate of multitarget stool DNA tests (mt-sDNA)/100 000 was the highest at 170.4 screenings/year (R2 = 0.99, p ≤ 0.001), while that of faecal occult blood tests/100 000 was the lowest at -446.4 screenings/year (R2 = 0.90, p ≤ 0.001) (p ≤ 0.001). Provider reimbursements averaged $546.95 (95% CI $520.12-$573.78) per mt-sDNA screening, significantly higher than reimbursements for all invasive screenings. Only FOBTs significantly increased in reimbursement per screening at $0.62/year (R2 = 0.91, p ≤ 0.001). CONCLUSION: We derived forecastable trend numbers for utilization and provider reimbursement. Faecal immunochemical tests/100 000 and mt-sDNA screenings/100 000 increased most rapidly during the entire study period. The number of nearly all invasive screenings/100 000 decreased rapidly; the number of colonoscopies/100 000 increased slightly, probably due to superior diagnostic strength. These trends indicate the that replacement of other invasive modalities with accessible noninvasive screenings will account for much of future screening behaviour and thus reductions in CRC incidence and mortality, especially given providers' reimbursement incentive to screen average-risk patients with stool-based tests.

Effectiveness and Cost-Effectiveness of Colorectal Cancer Screening With a Blood Test That Meets the Centers for Medicare & Medicaid Services Coverage Decision.

BACKGROUND & AIMS: A blood-based colorectal cancer (CRC) screening test may increase screening participation. However, blood tests may be less effective than current guideline-endorsed options. The Centers for Medicare & Medicaid Services (CMS) covers blood tests with sensitivity of at least 74% for detection of CRC and specificity of at least 90%. In this study, we investigate whether a blood test that meets these criteria is cost-effective. METHODS: Three microsimulation models for CRC (MISCAN-Colon, CRC-SPIN, and SimCRC) were used to estimate the effectiveness and cost-effectiveness of triennial blood-based screening (from ages 45 to 75 years) compared to no screening, annual fecal immunochemical testing (FIT), triennial stool DNA testing combined with an FIT assay, and colonoscopy screening every 10 years. The CMS coverage criteria were used as performance characteristics of the hypothetical blood test. We varied screening ages, test performance characteristics, and screening uptake in a sensitivity analysis. RESULTS: Without screening, the models predicted 77-88 CRC cases and 32-36 CRC deaths per 1000 individuals, costing $5.3-$5.8 million. Compared to no screening, blood-based screening was cost-effective, with an additional cost of $25,600-$43,700 per quality-adjusted life-year gained (QALYG). However, compared to FIT, triennial stool DNA testing combined with FIT, and colonoscopy, blood-based screening was not cost-effective, with both a decrease in QALYG and an increase in costs. FIT remained more effective (+5-24 QALYG) and less costly (-$3.2 to -$3.5 million) than blood-based screening even when uptake of blood-based screening was 20 percentage points higher than uptake of FIT. CONCLUSION: Even with higher screening uptake, triennial blood-based screening, with the CMS-specified minimum performance sensitivity of 74% and specificity of 90%, was not projected to be cost-effective compared with established strategies for colorectal cancer screening.

Comparative Effectiveness and Cost-Effectiveness of Colorectal Cancer Screening With Blood-Based Biomarkers (Liquid Biopsy) vs Fecal Tests or Colonoscopy.

BACKGROUND & AIMS: Colorectal cancer (CRC) screening is highly effective but underused. Blood-based biomarkers (liquid biopsy) could improve screening participation. METHODS: Using our established Markov model, screening every 3 years with a blood-based test that meets minimum Centers for Medicare & Medicaid Services' thresholds (CMSmin) (CRC sensitivity 74%, specificity 90%) was compared with established alternatives. Test attributes were varied in sensitivity analyses. RESULTS: CMSmin reduced CRC incidence by 40% and CRC mortality by 52% vs no screening. These reductions were less profound than the 68%-79% and 73%-81%, respectively, achieved with multi-target stool DNA (Cologuard; Exact Sciences) every 3 years, annual fecal immunochemical testing (FIT), or colonoscopy every 10 years. Assuming the same cost as multi-target stool DNA, CMSmin cost $28,500/quality-adjusted life-year gained vs no screening, but FIT, colonoscopy, and multi-target stool DNA were less costly and more effective. CMSmin would match FIT's clinical outcomes if it achieved 1.4- to 1.8-fold FIT's participation rate. Advanced precancerous lesion (APL) sensitivity was a key determinant of a test's effectiveness. A paradigm-changing blood-based test (sensitivity >90% for CRC and 80% for APL; 90% specificity; cost ≤$120-$140) would be cost-effective vs FIT at comparable participation. CONCLUSIONS: CMSmin could contribute to CRC control by achieving screening in those who will not use established methods. Substituting blood-based testing for established effective CRC screening methods will require higher CRC and APL sensitivities that deliver programmatic benefits matching those of FIT. High APL sensitivity, which can result in CRC prevention, should be a top priority for screening test developers. APL detection should not be penalized by a definition of test specificity that focuses on CRC only.

Cost-effectiveness analysis of single colonoscopy versus single fecal test for colorectal cancer diagnosis and treatment.

BACKGROUND AND AIM: Regular endoscopy or fecal immunochemical test (FIT) is ideal for screening colorectal cancer. However, only a limited number of individuals undergo regular screening. This study aimed to compare the cost-effectiveness of a single colonoscopy with a single FIT performed for colorectal cancer screening. METHODS: A microsimulation model was constructed based on real-world observational data collected from three institutions between 2019 and 2022 that compared colonoscopy-based screening with FIT-based screening. The total costs of diagnosis and treatment of the detected lesions using the two strategies were calculated. The incremental cost-effectiveness ratio (ICER) per life year gained (LYG) of the colonoscopy-based strategy was calculated. RESULTS: Data from 11 407 patients undergoing colonoscopies and 59 176 patients undergoing FITs were used to establish a model. In the base case analysis of screening strategies, colonoscopy was more cost-effective than FIT (ICER 415 193 yen/LYG). The ICER of the colonoscopy-based strategy among 60- to 69-year-old patients was lowest at 394 200 yen/LYG, whereas that in 20- to 29-year-old patients was highest. Monte Carlo simulations showed that the colonoscopy-based strategy was more cost-effective than the FIT-based strategy (net monetary benefit [NMB]: 5 695 957 yen vs 5 348 253 yen). When the adenoma detection rate in the colonoscopy was over 30% or the positive FIT rate was lower than 8.6% in the FIT-based strategy, the NMB of the colonoscopy-based strategy exceeded that of the FIT-based strategy. CONCLUSION: In the microsimulation model, colonoscopy is recommended as a one-time screening procedure in patients aged >60 years with >30% ADR or <8.6% positive FIT rate.

Costs and outcomes of colorectal cancer screening program in Isfahan, Iran.

BACKGROUND: Colorectal cancer is one of the most prevalent gastrointestinal cancers in Iran i.e., the fourth and the second prevalent cancer among Iranian males and females, respectively. A routine screening program is effective in the early detection of disease which can reduce the cancer burden both for individuals and society. In 2015, Iran's Package of Essential Non- communicable Diseases program had been piloted in Shahreza city in Isfahan province. Colorectal cancer screening for the population aged 50-70 was a part of this program. So far, there was no study about the cost and outcomes of that program. Thus, this study aimed to analyze the costs and outcomes of colorectal cancer screening done from 2016 to 2019 in Shahreza. METHODS: This cost-outcome description study used the data of 19,392 individuals who were 50-70 years old experienced a fecal immunochemical test (FIT) and had an electronic health record. All direct costs including personnel, building space, equipment, training, etc. were extracted from the financial documents existing in the Isfahan province Health Center. The outcome was defined as positive FIT, detection of adenoma or malignancy as recorded in the E-integrated health system. RESULTS: The results of this study indicated that the direct costs of the colorectal cancer screening program during the years 2016-2019 were 7,368,707,574 Rials (321,029 PPP$) in Shahreza, Isfahan province. These costs resulted in identifying 821 people with a positive FIT test, of those 367 individuals were undergone colonoscopy. Of whom 8 cases of colorectal cancer, and 151 cases with polyps were diagnosed. CONCLUSION: This study showed that by paying a small amount of 320 thousand international dollars we could prevent 151 cases of polyps to be progressed to colorectal cancer,resulting in a significant reduction in colorectal cancer incidence.

The Cost of Guideline Adherence: A Multicenter Analysis of the Financial Implications of Adopting the US Multi-Society Task Force Polypectomy Guidelines.

GOAL: The goal of this study was to determine the financial impact of adopting the US Multi-Society Task Force (USMSTF) polypectomy guidelines on physician reimbursement and disposable equipment costs for gastroenterologists in the academic medical center and community practice settings. BACKGROUND: In 2020, USMSTF guidelines on polypectomy were introduced with a strong recommendation for cold snare rather than cold forceps technique for removing diminutive and small polyps. Polypectomy with snare technique reimburses physicians at a higher rate compared with cold forceps and also requires different disposable equipment. The financial implications of adopting these guidelines is unknown. MATERIALS AND METHODS: Patients that underwent screening colonoscopy where polypectomy was performed at an academic medical center (Loma Linda University Medical Center) and community practice medical center (Ascension Providence Hospital) between July 2018 and July 2019 were identified. The polypectomy technique performed during each procedure was determined (forceps alone, snare alone, forceps plus snare) along with the number and size of polyps as well as disposable equipment. Actual and projected provider reimbursement and disposable equipment costs were determined based on applying the new polypectomy guidelines. RESULTS: A total of 1167 patients underwent colonoscopy with polypectomy. Adhering to new guidelines would increase estimated physician reimbursement by 5.6% and 12.5% at academic and community practice sites, respectively. The mean increase in physician reimbursement per procedure was significantly higher at community practice compared with the academic setting ($29.50 vs. $14.13, P <0.00001). The mean increase in disposable equipment cost per procedure was significantly higher at the community practice setting ($6.11 vs. $1.97, P <0.00001). CONCLUSION: Adopting new polypectomy guidelines will increase physician reimbursement and equipment costs when colonoscopy with polypectomy is performed.

Change in Colorectal Cancer Tests Submitted for Reimbursement in Switzerland 2012-2018: Evidence from Claims Data of a Large Insurance.

Objectives: Guidelines recommend colorectal cancer (CRC) screening by fecal occult blood test (FOBT) or colonoscopy. In 2013, Switzerland introduced reimbursement of CRC screening by mandatory health insurance for 50-69-years-olds, after they met their deductible. We hypothesized that the 2013 reimbursement policy increased testing rate. Methods: In claims data from a Swiss insurance, we determined yearly CRC testing rate among 50-75-year-olds (2012-2018) and the association with socio-demographic, insurance-, and health-related covariates with multivariate-adjusted logistic regression models. We tested for interaction of age (50-69/70-75) on testing rate over time. Results: Among insurees (2012:355'683; 2018:348'526), yearly CRC testing rate increased from 2012 to 2018 (overall: 8.1-9.9%; colonoscopy: 5.0-7.6%; FOBT: 3.1-2.3%). Odds ratio (OR) were higher for 70-75-year-olds (2012: 1.16, 95%CI 1.13-1.20; 2018: 1.05, 95%CI 1.02-1.08). Deductible interacted with changes in testing rate over time (p < 0.001). The increase in testing rate was proportionally higher among 50-69-years-olds than 70-75-year-olds over the years. Conclusions: CRC testing rate in Switzerland increased from 2012 to 2018, particularly among 50-69-years-olds, the target population of the 2013 law. Future studies should explore the effect of encouraging FOBT or waiving deductible.

Factors predicting improved compliance towards colonoscopy in individuals with positive faecal immunochemical test (FIT).

OBJECTIVES: Follow-up colonoscopy after a positive faecal immunochemical test (FIT) in any colorectal cancer (CRC) screening programme is integral. However, many individuals who had a positive FIT declined colonoscopy subsequently. This study aims to uncover the predictors on completion of colonoscopy using the Health Belief Model (HBM) between individuals who complete and those who did not after a positive FIT. METHODS: A mixed-method study comprising qualitative semi-structured interviews followed by a locally validated questionnaire in Singapore was prospectively administered via telephone interview to average risk individuals with positive FIT results from a cohort of the national FIT screening database referred for follow-up colonoscopic evaluation. RESULTS: A total of 394 individuals, with a median age of 66 years (range, 46-89 years), were recruited. Fifty percent completed follow-up colonoscopic evaluation and formed the "doers" group. All participants demonstrated high knowledge of symptoms of CRC and awareness and qualitative responses were aligned to the various HBM domains. Using multi-variable analysis, doers felt that medical recommendations (odds ratio [OR], 2.39, 95% confidence interval [CI]: 1.23-4.63, p = 0.01) and mainstream media publicity (OR, 2.16, 95% CI: 1.09-4.26, p = 0.026) were important. Non-doers showed positive association with perceived barriers such as cost (OR, 2.15, 95% CI: 1.10-4.20, p = 0.026) and inconvenience (OR, 3.44, 95% CI: 1.50-7.89, p = 0.004). CONCLUSIONS: Identified factors such as tackling perceived barriers, public health education and active promotion by medical physicians, family and friends could help guide subsequent interventions to improve compliance of individuals with positive FIT to undergo follow-up colonoscopy.

Optimizing Positivity Thresholds for a Risk-Adapted Screening Strategy in Colorectal Cancer Screening.

INTRODUCTION: Risk-adapted screening combining the Asia-Pacific Colorectal Screening score, fecal immunochemical test (FIT), and colonoscopy improved the yield of colorectal cancer screening than FIT. However, the optimal positivity thresholds of risk scoring and FIT of such a strategy warrant further investigation. METHODS: We included 3,407 participants aged 50-74 years undergoing colonoscopy from a colorectal cancer screening trial. For the risk-adapted screening strategy, subjects were referred for subsequent colonoscopy or FIT according to their risk scores. Diagnostic performance was evaluated for FIT and the risk-adapted screening method with various positivity thresholds. Furthermore, a modeled screening cohort was established to compare the yield and cost using colonoscopy, FIT, and the risk-adapted screening method in a single round of screening. RESULTS: Risk-adapted screening method had higher sensitivity for advanced neoplasm (AN) (27.6%-76.3% vs 13.8%-17.3%) but lower specificity (46.6%-90.8% vs 97.4%-98.8%) than FIT did. In a modeled screening cohort, FIT-based screening would be slightly affected because the threshold varied with a reduction of 76.0%-80.9% in AN detection and 82.0%-84.4% in cost when compared with colonoscopy. By contrast, adjusting the threshold of Asia-Pacific Colorectal Screening score from 3 to 5 points for risk-adapted screening varied from an increase of 12.6%-14.1% to a decrease of 55.6%-60.1% in AN detection, with the reduction of cost from 4.2%-5.3% rising to 66.4%-68.5%. DISCUSSION: With an appropriate positivity threshold tailored to clinical practice, the risk-adapted screening could save colonoscopy resources and cost compared with the colonoscopy-only and FIT-only strategies.

The Costs and Benefits of Risk Stratification for Colorectal Cancer Screening Based On Phenotypic and Genetic Risk: A Health Economic Analysis.

Population-based screening for colorectal cancer is an effective and cost-effective way of reducing colorectal cancer incidence and mortality. Many genetic and phenotypic risk factors for colorectal cancer have been identified, leading to development of colorectal cancer risk scores with varying discrimination. However, these are not currently used by population screening programs. We performed an economic analysis to assess the cost-effectiveness, clinical outcomes, and resource impact of using risk-stratification based on phenotypic and genetic risk, taking a UK National Health Service perspective. Biennial fecal immunochemical test (FIT), starting at an age determined through risk-assessment at age 40, was compared with FIT screening starting at a fixed age for all individuals. Compared with inviting everyone from age 60, using a risk score with area under the receiver operating characteristic curve of 0.721 to determine FIT screening start age, produces 418 QALYs, costs £247,000, and results in 218 fewer colorectal cancer cases and 156 fewer colorectal cancer deaths per 100,000 people, with similar FIT screening invites. There is 96% probability that risk-stratification is cost-effective, with net monetary benefit (based on £20,000 per QALY threshold) estimated at £8.1 million per 100,000 people. The maximum that could be spent on risk-assessment and still be cost-effective is £114 per person. Lower benefits are produced with lower discrimination risk scores, lower mean screening start age, or higher FIT thresholds. Risk-stratified screening benefits men more than women. Using risk to determine FIT screening start age could improve the clinical outcomes and cost effectiveness of colorectal cancer screening without using significant additional screening resources. PREVENTION RELEVANCE: Colorectal cancer screening is essential for early detection and prevention of colorectal cancer, but implementation is often limited by resource constraints. This work shows that risk-stratification using genetic and phenotypic risk could improve the effectiveness and cost-effectiveness of screening programs, without using substantially more screening resources than are currently available.

Cost-Effectiveness of Multitarget Stool DNA Testing vs Colonoscopy or Fecal Immunochemical Testing for Colorectal Cancer Screening in Alaska Native People.

OBJECTIVE: To estimate the cost-effectiveness of multitarget stool DNA testing (MT-sDNA) compared with colonoscopy and fecal immunochemical testing (FIT) for Alaska Native adults. PATIENTS AND METHODS: A Markov model was used to evaluate the 3 screening test effects over 40 years. Outcomes included colorectal cancer (CRC) incidence and mortality, costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). The study incorporated updated evidence on screening test performance and adherence and was conducted from December 15, 2016, through November 6, 2019. RESULTS: With perfect adherence, CRC incidence was reduced by 52% (95% CI, 46% to 56%) using colonoscopy, 61% (95% CI, 57% to 64%) using annual FIT, and 66% (95% CI, 63% to 68%) using MT-sDNA. Compared with no screening, perfect adherence screening extends life by 0.15, 0.17, and 0.19 QALYs per person with colonoscopy, FIT, and MT-sDNA, respectively. Colonoscopy is the most expensive strategy: approximately $110 million more than MT-sDNA and $127 million more than FIT. With imperfect adherence (best case), MT-sDNA resulted in 0.12 QALYs per person vs 0.05 and 0.06 QALYs per person by FIT and colonoscopy, respectively. Probabilistic sensitivity analyses supported the base-case analysis. Under varied adherence scenarios, MT-sDNA either dominates or is cost-effective (ICERs, $1740-$75,868 per QALY saved) compared with FIT and colonoscopy. CONCLUSION: Each strategy reduced costs and increased QALYs compared with no screening. Screening by MT-sDNA results in the largest QALY savings. In Markov model analysis, screening by MT-sDNA in the Alaska Native population was cost-effective compared with screening by colonoscopy and FIT for a wide range of adherence scenarios.

Gene-Specific Variation in Colorectal Cancer Surveillance Strategies for Lynch Syndrome.

BACKGROUND AND AIMS: Lynch syndrome is associated with pathogenic variants in 4 mismatch repair (MMR) genes that increase lifetime risk of colorectal cancer. Guidelines recommend intensive colorectal cancer surveillance with colonoscopy every 1-2 years starting at age 25 years for all carriers of Lynch syndrome-associated variants, regardless of gene product. We constructed a simulation model to analyze the effects of different ages of colonoscopy initiation and surveillance intervals for each MMR gene (MLH1, MSH2, MSH6, and PMS2) on colorectal cancer incidence and mortality, quality-adjusted life-years, and cost. METHODS: Using published literature, we developed a Markov simulation model of Lynch syndrome progression for patients with each MMR variant. The model simulated clinical trials of Lynch syndrome carriers, varying age of colonoscopy initiation (5-year increments from 25-40 years), and surveillance intervals (1-5 years). We assessed the optimal strategy for each gene, defined as the strategy with the highest quality-adjusted life-years and incremental cost-effectiveness ratio below a $100,000 willingness-to-pay threshold. RESULTS: Optimal surveillance for patients with pathogenic variants in the MLH1 and MSH2 genes was colonoscopy starting at age 25 years, with 1- to 2-year surveillance intervals. Initiating colonoscopy at age 35 and 40 years, with 3-year intervals, was cost-effective for patients with pathogenic variants in MSH6 or PMS2, respectively. CONCLUSIONS: We developed a simulation model to select optimal surveillance starting ages and intervals for patients with Lynch syndrome based on MMR variant. The model supports recommendations for intensive surveillance of patients with Lynch syndrome-associated variants in MLH1 or MSH2. However, for patients with Lynch syndrome-associated variants of MSH6 or PMS2, later initiation of surveillance at 35 and 40 years, respectively, and at 3-year intervals, can be considered.

Should colorectal cancer screening start at different ages for men and women? Cost-effectiveness analysis for a resource-constrained service.

BACKGROUND: Men have a greater risk of colorectal cancer (CRC) than women, but population screening currently starts at the same age for both sexes. AIM: This analysis investigates whether, in a resource-constrained setting, it would be more effective and cost-effective for men and women to start screening for CRC at different ages. METHODS AND RESULTS: An economic modeling analysis was carried out using the Microsimulation Model in Cancer of the Bowel to compare sex-stratification against screening everyone from the same age, taking an English National Health Service perspective. Screening men from age 56 and women from age 60, rather than screening everyone from age 58 using a Fecal Immunochemical Test (FIT) threshold of 120 µg/g is expected to produce an additional 0.0004 QALYs for a cost of £0.55 per person at model start (Incremental Cost-effectiveness Ratio = £1392), and to reduce CRC cases and mortality by 25 and 19 per 100 000 people respectively, while using a similar amount of screening resources. Probabilistic sensitivity analysis indicates a 61% probability that sex-stratification is more cost-effective than screening everyone at age 58. Similar benefits of sex-stratification are found at other FIT thresholds, but become negligible if mean screening start age is reduced to 50. CONCLUSION: Where resources are constrained and it is not feasible to screen everyone from the age of 50, starting screening earlier in men than women is likely to be more cost-effective and gain more health benefits overall than strategies where men and women start screening at the same age.

Real-World Use of Colonoscopy in an Older Population: A Nationwide Standard Cohort Study Using a Common Data Model.

BACKGROUNDS AND AIMS: Rapid population aging is considered to be a major factor in increased colonoscopy use in Korea. However, real-world use of colonoscopy in older populations is rarely evaluated using Korean databases. METHODS: We conducted a retrospective, observational cohort study of individuals aged over 20 years between 2012 and 2017. We used the Health Insurance Review and Assessment-National Patient Samples database, previously converted to the standardized Observational Medical Outcomes Partnership-Common Data Model. The use of diagnostic colonoscopy and colonoscopic polypectomy was evaluated, stratified by age group and sex. RESULTS: During the study period, we captured data from the database on 240,406 patients who underwent diagnostic colonoscopy and 88,984 who underwent colonoscopic polypectomy. During the study period, use of diagnostic colonoscopy and colonoscopic polypectomy steadily increased, but both procedures were most significantly increased in the 65- to 85-year group compared to other age groups (p < 0.05). Average ages for both procedures significantly increased in the most recent 3 years (p < 0.05). Polypectomy rates for men plateaued in the 50- to 64-year age group, but rates for women steadily increased up to the 65- to 85-year group. Polypectomy rates were higher for men than for women in all index years. CONCLUSIONS: The use of diagnostic colonoscopy and colonoscopic polypectomy significantly increased in the 65- to 85-year age group. Our findings suggest that more available colonoscopy resources should be allocated to older populations, considering the aging society in Asian countries.