Cost-effectiveness of colonoscopy

Colorectal Cancer Screening Programs in Latin America: A Systematic Review and Meta-Analysis

Importance

Colorectal cancer (CRC) is a leading cause of cancer-related mortality globally, with increasing incidence and mortality in Latin America. CRC screening programs can reduce disease burden, but information on screening programs in Latin America is limited.

Objective

To describe characteristics (eg, type of program, uptake, neoplastic yield) of CRC screening programs in Latin America.

Data Sources

PubMed, Ovid MEDLINE, EMBASE, Cochrane, PsycINFO, Web of Science Core Collection, LILACS, and SciELO were searched from inception to February 2023. Relevant references from bibliographies, conference proceedings, and gray literature were considered. The search strategy included English, Spanish, and Portuguese terms.

Study Selection

Included were studies of CRC screening programs in Latin America using fecal immunochemical test (FIT) or colonoscopy as the primary screening method. Four reviewers independently assessed study eligibility based on titles, with review of abstracts and full texts as needed.

Data Extraction and Synthesis

Guidelines from Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were followed for data abstraction and quality assessment. Descriptive information was extracted, and data were pooled using a random-effects model.

Main outcomes and Measures

Program performance indicators included rates of participation and FIT positivity, adenoma detection rate (ADR), advanced adenoma detection rate (AADR), CRC detection rate, and colonoscopy quality indicators.

Results

There were 17 studies included from upper middle-income and high-income countries in Latin America with a total of 123 929 participants. Thirteen studies used FIT as the initial screening method, whereas 4 used screening colonoscopy. The participation rate in FIT-based programs was 85.8% (95% CI, 78.5%-91.4%). FIT positivity rates were 15.2% (95% CI, 9.6%-21.8%) for the 50-ng/mL threshold and 9.7% (95% CI, 6.8%-13.0%) for the 100-ng/mL threshold. For FIT-based studies, the pooled ADR was 39.0% (95% CI, 29.3%-49.2%) and CRC detection rate was 4.9% (95% CI, 2.6%-7.9%); for screening colonoscopy-based studies, the pooled ADR was 19.9% (95% CI, 15.5%-24.8%) and CRC detection rate was 0.4% (95% CI, 0.1%-0.8%).

Conclusions and Relevance

This systematic review and meta-analysis suggests that CRC screening in upper middle-income countries in Latin America is feasible, detecting rates of neoplasia comparable with those of high-income regions. Population-based screening programs should be developed or enhanced in these settings. There is a knowledge gap regarding feasibility and yield of screening programs in lower middle-income countries.

Concordance between nice classification and histopathology in colonic polyps: a tertiary center experience

Background

Narrow-Band imaging International Colorectal Endoscopic (NICE) could reduce histopathology study requirements in colorectal polyp evaluation. Local and regional studies are required to validate its utility.

Objectives

To evaluate concordance between NICE classification and histopathology.

Design

Prospective analytic study performed in the Hospital Universitario San Ignacio, Bogotá (Colombia) between 2021 and 2022.

Methods

Concordance between NICE I, II and III classification and histopathology [Hyperplastic Polyp (HP), adenoma and deep submucosal invasive cancer (DSIC)] was evaluated using weighted kappa. Diagnostic performance was evaluated for NICE I-II versus NICE III for DSIC versus adenoma/HP. A subgroup analysis was performed for polyps ⩾10 mm and those located in the rectum, sigmoid, and left colon.

Results

A total of 238 polyps from 135 patients were evaluated. Median age 67 years (IQR 58.5-74.5), 54.4% males. 23 (17.1%) had ⩾3 polyps. Of polyps, 52.1% were located on rectum, sigmoid and left colon. A total of 182 (76.5%) were <10 mm. NICE and histopathology evidenced a fair-moderate concordance (quadratic weighted kappa 0.36, linear weighted kappa 0.43). NICE classification (NICE I-II versus III) compared to histopathology (DSIC versus adenoma/HP) evidenced a sensitivity of 90.9% and specificity of 99.1%. For DSIC diagnosis specificity was ⩾95% on polyps ⩾10 mm and those left sided located.

Conclusion

NICE and histopathology concordance is suboptimal. However, NICE III for DSIC diagnosis evidence good specificity. Therefore, NICE III polyps require a prompt histopathological evaluation and follow-up. Good operative characteristics stand in polyps ⩾10 mm and left sided located. NBI formal training is recommended in gastroenterology units in Latin America.

Differential impact of test performance characteristics on burden-to-benefit tradeoffs for blood-based colorectal cancer screening: A microsimulation analysis

OBJECTIVES

To inform the development and evaluation of new blood-based colorectal cancer (CRC) screening tests satisfying minimum United States (US) coverage criteria, we estimated the impact of the different test performance characteristics on long-term testing benefits and burdens.

METHODS

A novel CRC-Microsimulation of Adenoma Progression and Screening (CRC-MAPS) model was developed, validated, then used to assess different screening tests for CRC. We compared multiple, hypothetical blood-based CRC screening tests satisfying minimum coverage criteria of 74% CRC sensitivity and 90% specificity, to measure how changes in a test's CRC sensitivity, specificity, and adenoma sensitivity (sizes 1-5 mm, 6-9 mm, ≥10 mm) affect total number of colonoscopies (COL), CRC incidence reduction (IR), CRC mortality reduction (MR), and burden-to-benefit ratios (incremental COLs per percentage-point increase in IR or MR).

RESULTS

A blood test meeting minimum US coverage criteria for performance characteristics resulted in 1576 lifetime COLs per 1000 individuals, 46.7% IR and 59.2% MR compared to no screening. Tests with increased CRC sensitivity of 99% ( + 25%) vs. increased ≥10 mm adenoma sensitivity of 13.6% ( + 3.6%) both yielded the same MR, 62.7%. Test benefits improved the most with increases in all-size adenoma sensitivity, then size-specific adenoma sensitivities, then specificity and CRC sensitivity, while increases in specificity or ≥10 mm adenoma sensitivity resulted in the most favorable burden-to-benefit tradeoffs (ratios <11.5).

CONCLUSIONS

Burden-to-benefit ratios for blood-based CRC screening tests differ by performance characteristic, with the most favorable tradeoffs resulting from improvements in specificity and ≥10 mm adenoma sensitivity.

Cost-Effectiveness of Liquid Biopsy for Colorectal Cancer Screening in Patients Who Are Unscreened

Importance

Despite recommendations for universal screening, adherence to colorectal cancer screening in the US is approximately 60%. Liquid biopsy tests are in development for cancer early detection, but it is unclear whether they are cost-effective for colorectal cancer screening.

Objective

To estimate the cost-effectiveness of liquid biopsy for colorectal cancer screening in the US.

Design, Setting, and Participants

In this economic evaluation, a Markov model was developed to compare no screening and 5 colorectal cancer screening strategies: colonoscopy, liquid biopsy, liquid biopsy following nonadherence to colonoscopy, stool DNA, and fecal immunochemical test. Adherence to first-line screening with colonoscopy, stool DNA, or fecal immunochemical test was assumed to be 60.6%, and adherence for liquid biopsy was assumed to be 100%. For colonoscopy, stool DNA, and fecal immunochemical test, patients who did not adhere to testing were not offered other screening. In colonoscopy-liquid biopsy hybrid, liquid biopsy was second-line screening for those who deferred colonoscopy. Scenario analyses were performed to include the possibility of polyp detection for liquid biopsy.

Exposures

No screening, colonoscopy, fecal immunochemical test, stool DNA, liquid biopsy, and colonoscopy-liquid biopsy hybrid screening.

Main Outcomes and Measures

Model outcomes included life expectancy, total cost, and incremental cost-effectiveness ratios. A strategy was considered cost-effective if it had an incremental cost-effectiveness ratio less than the US willingness-to-pay threshold of $100 000 per life-year gained.

Results

This study used a simulated cohort of patients aged 45 years with average risk of colorectal cancer. In the base case, colonoscopy was the preferred, or cost-effective, strategy with an incremental cost-effectiveness ratio of $28 071 per life-year gained. Colonoscopy-liquid biopsy hybrid had the greatest gain in life-years gained but had an incremental cost-effectiveness ratio of $377 538. Colonoscopy-liquid biopsy hybrid had a greater gain in life-years if liquid biopsy could detect polyps but remained too costly.

Conclusions and Relevance

In this economic evaluation of liquid biopsy for colorectal cancer screening, colonoscopy was a cost-effective strategy for colorectal cancer screening in the general population, and the inclusion of liquid biopsy as a first- or second-line screening strategy was not cost-effective at its current cost and screening performance. Liquid biopsy tests for colorectal cancer screening may become cost-effective if their cost is substantially lowered.

How Would You Screen This Patient for Colorectal Cancer? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Colorectal cancer (CRC) is the third leading cause of cancer death for men and women in the United States, with an estimated 52 580 people expected to die in 2022. Most frequently, CRC is diagnosed among persons aged 65 to 74 years. However, among persons younger than 50 years, incidence rates have been increasing since the mid-1990s. In 2021, partially because of the rising incidence, the U.S. Preventive Services Task Force (USPSTF) recommended CRC screening for adults aged 45 to 49 years (Grade B recommendation). Options for CRC screening include stool-based and direct visualization tests. The USPSTF did not recommend a specific screening test; rather, its guidance was to select a test after a discussion with the patient. Here, a primary care physician and a gastroenterologist discuss the recommendation to begin CRC screening at age 45, review options for CRC screening, and discuss how to choose among the available options.

Process Evaluation of a Mailed Interactive Educational DVD in a Comparative Effectiveness Trial to Promote Colorectal Cancer Screening

A process evaluation was conducted as part of a comparative effectiveness trial of a mailed interactive educational DVD intervention to promote colorectal cancer screening among average-risk patients who did not attend a scheduled colonoscopy. Participants (n = 371) for the trial were randomized to (1) mailed DVD, (2) mailed DVD plus patient navigation, or (3) usual care. Participants (n = 243) randomized to the two DVD intervention arms were called 2 weeks after mailing materials to complete a process evaluation interview about the DVD (September 2017-February 2020). Forty-nine (20%) participants were not reached, and 194 (80%) participants watched the DVD and completed the interview. The process evaluation assessed whether (1) the DVD content was helpful, (2) any new information was learned by participants, (3) the appropriate amount of information was included in the DVD, (4) participants were engaged when watching the DVD, (5) the DVD content was relevant, (6) participants were satisfied with the DVD (7) participants would recommend the DVD to others, and (8) their opinion about colorectal cancer screening was changed by watching the DVD. Among participants who watched the DVD, 99% reported the screening information was very or somewhat helpful, 47% learned new information, 75% said the DVD included the right amount of information, they were engaged (M = 3.35 out of 4, SD = 0.49), 87% reported all or most information applied to them, they were satisfied (M = 3.42 out of 4, SD = 0.39) with DVD content, 99% would recommend the DVD to others, and 45% reported changing their opinion about screening. To understand the effects of interventions being tested in trials and to plan the dissemination of evidence-based interventions, process evaluation is critical to assess the dose received and acceptability of behavioral interventions.

The role of sex and rurality in cancer fatalistic beliefs and cancer screening utilization in Florida

BACKGROUND

People's fatalistic beliefs about cancer can influence their cancer prevention behaviors. We examined the association between fatalistic beliefs and breast and colorectal cancer screening among residents of north-central Florida and tested whether there exists any sex or rural-non-rural disparities in the association.

METHODS

We conducted a cross-sectional, random digit dialing telephone survey of 895 adults residing in north-central Florida in 2017. Using weighted logistic models, we examined the association between (1) respondents' sociodemographic characteristics and cancer fatalistic beliefs and (2) cancer fatalistic beliefs and cancer screening utilization among screening eligible populations. We tested a series of sex and rurality by fatalistic belief interactions.

RESULTS

Controlling for sociodemographics, we found the agreement with "It seems like everything causes cancer" was associated with a higher likelihood of having a mammogram (odds ratio [OR]: 3.34; 95% confidence interval [CI]: 1.17-9.51), while the agreement with "Cancer is most often caused by a person's behavior or lifestyle" was associated with a higher likelihood of having a blood stool test (OR: 1.85; 95% CI: 1.12-3.05) or a sigmoidoscopy or colonoscopy among women (OR: 2.65; 95% CI: 1.09-6.44). We did not observe any rural-non-rural disparity in the association between fatalistic beliefs and cancer screening utilization.

CONCLUSIONS

Some, but not all, cancer fatalistic beliefs are associated with getting breast and colorectal cancer screening in north-central Florida. Our study highlights the need for more research to better understand the social and cultural factors associated with cancer screening utilization.

Microsimulation Model to Determine the Cost-Effectiveness of Treat-to-Target Strategies for Ulcerative Colitis

BACKGROUND & AIMS

Little is known about the cost effectiveness of endoscopy or biomarker-based treat to target monitoring of patients with ulcerative colitis (UC).

METHODS

We used a microsimulation model to identify the most cost effective treat to target monitoring strategy for patients with UC staring therapy with biologics or small molecule inhibitors. We assessed symptoms (rectal bleeding) alone, a combination of symptoms and a biomarker (fecal calprotectin), and endoscopy. Transition probabilities, costs, and quality-adjusted life year (QALY) estimates were derived from published estimates. The microsimulation model tracked an individual patient's disease course and treatment exposures to modify downstream treatment effectiveness, probabilities, and disease outcomes. The primary analysis included 100,000 individuals over 5 years with a willingness to pay threshold of $100,000/QALY. Probabilistic sensitivity analyses were performed with 500 samples and 250 trials, in addition to multiple 1-, 2-, and 3-way microsimulation sensitivity analyses.

RESULTS

A total of 32 treatment sequencing algorithms were modeled alongside 3 disease monitoring strategies within a treat to target approach for UC. Combination symptom and biomarker-based monitoring resulted in the highest QALY estimate among all the treatment sequencing algorithms. However, monitoring disease activity with symptoms alone was the most cost-effective strategy in 86% of scenarios, followed by combination symptom and biomarker monitoring in 9%, and endoscopy monitoring in 5%. Results were sensitive to treatment costs, patient willingness to consider colectomy as a treatment option, and endoscopy costs. Endoscopy-based monitoring was favored when treatment costs were high and patients were unwilling to undergo colectomy.

CONCLUSIONS

The combination symptom and biomarker-based monitoring resulted in the highest QALY estimate. However, symptom-based monitoring is the most cost-effective approach to implementing treat to target monitoring for patients with UC receiving biologics and small molecule inhibitors.

A novel value-based scoring system for endoscopic ultrasound-guided drainage of pancreatic fluid collections: a single-centre comparative study of plastic and lumen-apposing metal stents (NOVA study)

OBJECTIVE

Healthcare resources are finite. Value in healthcare can be defined as patient health outcomes achieved per monetary unit spent. Attempts have been made to quantify the value of luminal endoscopy, but there is little in the medical literature describing the value of the complex therapeutic endoscopic activity. This study aimed to characterise the value of endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFCs) with either plastic or lumen-apposing metal stents (LAMSs).

METHODS

This is a single-centre, retrospective-prospective comparative study of 39 patients, who underwent EUS-guided PFC drainage between 2009 and 2018. Procedure value was calculated using the formula Q/(T/C), where Q is the quality of procedure adjusted for complications, T procedure duration and C is the complexity adjustment. Quality and complexity were estimated on a 1-4 Likert scale based on the American Society for Gastrointestinal Endoscopy criteria. Time (in minutes) was recorded from the patient entering and leaving the procedure room. Endoscopy time calculated from procedure time was considered a surrogate marker of cost as individual components of procedure cost were not itemized.

RESULTS

Of 39 identified patients who underwent EUS-guided PFC drainage, 11 received double pigtail plastic stents (DPPSs) and 28 received LAMSs. The two groups were comparable in age, gender and aetiology. Nearly 40% of the LAMS interventions were considered high value but only 11% of the plastic stent interventions achieved the same. The difference predominantly was due to a higher rate of complications and longer procedure time.

CONCLUSION

In this single-centre study, EUS-guided PFC drainage using LAMS was found to be a higher value procedure compared to the use of DPPS.

Fertility Impact of Initial Operation Type for Female Ulcerative Colitis Patients

BACKGROUND

Ileal pouch-anal anastomosis (IPAA) is the mainstay of surgical treatment for patients with ulcerative colitis (UC) but is associated with an increased risk of infertility. We developed a simulation model examining the impact of initial surgical procedure on quality-adjusted life-years (QALYs) and fertility end points.

METHODS

A patient-level state transition model was used to analyze outcomes by surgical approach strategy for females of childbearing age. Initial surgical options included IPAA, rectal-sparing colectomy with end ileostomy (RCEI), and ileorectal anastomosis (IRA). The primary outcome examined was QALYs, whereas secondary outcomes included UC and fertility-associated end points.

RESULTS

IPAA resulted in higher QALYs for patients aged 20-30 years, as compared with RCEI. For patients aged 35 years, RCEI resulted in higher QALYs (7.54 RCEI vs 7.53 IPAA) and was associated with a 28% higher rate of childbirth, a 14-month decrease in time to childbirth, and a 77% reduction in in vitro fertilization utilization. When accounting for the decreased infertility risk associated with laparoscopic IPAA, IPAA resulted in higher QALYs (7.57) even for patients aged 35 years.

CONCLUSIONS

Despite an increased risk of infertility, our model results suggest that IPAA may be the optimal surgical strategy for female UC patients aged 20-30 years who desire children. For patients aged 35 years, RCEI should additionally be considered, as QALYs for RCEI and IPAA were similar. These quantitative data can be used by patients and providers to help develop an individualized approach to surgical management choice.

Effectiveness, benefit harm and cost effectiveness of colorectal cancer screening in Austria

BACKGROUND

Clear evidence on the benefit-harm balance and cost effectiveness of population-based screening for colorectal cancer (CRC) is missing. We aim to systematically evaluate the long-term effectiveness, harms and cost effectiveness of different organized CRC screening strategies in Austria.

METHODS

A decision-analytic cohort simulation model for colorectal adenoma and cancer with a lifelong time horizon was developed, calibrated to the Austrian epidemiological setting and validated against observed data. We compared four strategies: 1) No Screening, 2) FIT: annual immunochemical fecal occult blood test age 40-75 years, 3) gFOBT: annual guaiac-based fecal occult blood test age 40-75 years, and 4) COL: 10-yearly colonoscopy age 50-70 years. Predicted outcomes included: benefits expressed as life-years gained [LYG], CRC-related deaths avoided and CRC cases avoided; harms as additional complications due to colonoscopy (physical harm) and positive test results (psychological harm); and lifetime costs. Tradeoffs were expressed as incremental harm-benefit ratios (IHBR, incremental positive test results per LYG) and incremental cost-effectiveness ratios [ICER]. The perspective of the Austrian public health care system was adopted. Comprehensive sensitivity analyses were performed to assess uncertainty.

RESULTS

The most effective strategies were FIT and COL. gFOBT was less effective and more costly than FIT. Moving from COL to FIT results in an incremental unintended psychological harm of 16 additional positive test results to gain one life-year. COL was cost saving compared to No Screening. Moving from COL to FIT has an ICER of 15,000 EUR per LYG.

CONCLUSIONS

Organized CRC-screening with annual FIT or 10-yearly colonoscopy is most effective. The choice between these two options depends on the individual preferences and benefit-harm tradeoffs of screening candidates.

Cost-Effectiveness of Cancer Screening: Health and Costs in Life Years Gained

INTRODUCTION

Studies reporting on the cost-effectiveness of cancer screening usually account for quality of life losses and healthcare costs owing to cancer but do not account for future costs and quality of life losses related to competing risks. This study aims to demonstrate the impact of medical costs and quality of life losses of other diseases in the life years gained on the cost-effectiveness of U.S. cancer screening.

METHODS

Cost-effectiveness studies of breast, cervical, and colorectal cancer screening in the U.S. were identified using a systematic literature review. Incremental cost-effectiveness ratios of the eligible articles were updated by adding lifetime expenditures and health losses per quality-adjusted life year gained because of competing risks. This was accomplished using data on medical spending and quality of life by age and disease from the Medical Expenditure Panel Survey (2011-2015) combined with cause-deleted life tables. The study was conducted in 2018.

RESULTS

The impact of quality of life losses and healthcare expenditures of competing risks in life years gained incurred owing to screening were the highest for breast cancer and the lowest for cervical cancer. The updates suggest that incremental cost-effectiveness ratios are underestimated by $10,300-$13,700 per quality-adjusted life year gained if quality of life losses and healthcare expenditures of competing risks are omitted in economic evaluations. Furthermore, cancer screening programs that were considered cost saving, were found not to be so following the inclusion of medical expenditures of competing risks.

CONCLUSIONS

Practical difficulties in quantifying quality of life losses and healthcare expenditures owing to competing risks in life years gained can be overcome. Their inclusion can have a substantial impact on the cost-effectiveness of cancer screening programs.

Screening for colorectal cancer after pancreatoduodenectomy for ampullary cancer

BACKGROUND

In some Dutch pancreatic surgery centers, patients who underwent pancreatoduodenectomy (PD) for ampullary cancer undergo surveillance for colorectal cancer (CRC), since an association is suggested in contemporary literature. This study aimed to examine the CRC incidence after PD for ampullary cancer in four pancreatic surgery centers and a Dutch nationwide cohort.

METHODS

All patients who underwent resection of ampullary cancer from 2005 through 2017 at four centers were included. All colonoscopies and CRC diagnoses in these patients were recorded. In addition all PDs for ampullary cancer in the Dutch Pathology Registry (2000-2017) were recorded along with the CRC diagnoses and compared with an age, sex, and year-matched cohort.

RESULTS

Out of 287 included patients by the four centers, 11% underwent a colonoscopy within one year after PD. Eight (2.7%) were diagnosed with CRC before PD and two (0.7%), at 14 and 72 months after PD. In the nationwide cohort comparison, the CRC incidence was similar before (2.6% versus 1.9%, P = 0.424) and after surgery (2.1% versus 3.1%, P = 0.237). Within one year after PD, the incidence was 0.3% compared to 0.6% in the matched controls (P = 0.726).

CONCLUSIONS

The current study could not find an increased risk of CRC in patients with resected ampullary cancer. Therefore, there is insufficient justification to screen for CRC in patients with resected ampullary cancer.

Assessing adherence and cost-benefit of colorectal cancer screening for accountable providers

The objective of this study was to assess adherence and costs-benefits of colorectal cancer (CRC) screenings from an accountable care organization/population health perspective. We performed a retrospective review of 94 patients (50-75 years of age) in an integrated safety net system for whom fecal CRC screening was abnormal for the period of June 1, 2014, to June 1, 2016. A cost-benefit model was constructed using Medicare payment rates and a sensitivity analysis. Most patients included in the study (64/94, 68%) received or were offered a colonoscopy. Of those receiving a colonoscopy, 24 of 45 (53%) had an abnormal finding. Total direct medical costs avoided by screening the patient panel was $32,926 but could have exceeded $63,237 had more patients received follow-up colonoscopies. A sensitivity analysis with 1000 patients demonstrated total monetary benefits between $2.2 million and $8.16 million when follow-up and colonoscopy rates were allowed to vary. Although the resulting rates of follow-up were within the range reported in the literature, there is room for improvement, especially considering the monetary benefit that could be used on other diseases. Health systems and payers should work cooperatively to structure payment models to better incentivize CRC screenings.

Changes in Breast and Colorectal Cancer Screening After Medicaid Expansion Under the Affordable Care Act

INTRODUCTION

Medicaid expansions following the Affordable Care Act have improved insurance coverage in low-income adults, but little is known about its impact on cancer screening. This study examined associations between Medicaid expansion timing and colorectal cancer (CRC) and breast cancer (BC) screening.

METHODS

Up-to-date and past 2-year CRC (n=95,400) and BC (women, n=43,279) screening prevalence were computed among low-income respondents aged 50-64 years in 2012, 2014, and 2016 Behavioral Risk Factor Surveillance System data. Respondents were grouped according to Medicaid expansion timing as: very early ([VE] six states expanding March 1, 2010-April 14, 2011), early (21 states expanding January 1, 2014-August 15, 2014), late (five states expanding January 1, 2015-July 1, 2016), and non-expansion states (19 states). Absolute adjusted difference-in-differences (aDDs) were computed in 2018-2019 (ref, non-expansion states).

RESULTS

Between 2012 and 2016, absolute up-to-date CRC screening increased by 8.8%, 2.9%, 2.4%, and 3.8% among low-income adults in VE, early, late, and non-expansion states, respectively. Past 2-year CRC screening increased by 8.0% in VE and 2.8% in non-expansion states, with an aDD of 4.9% (p=0.041). In 2012-2016, up-to-date BC screening increased by 5.1%, 4.9%, and 3.7% among low-income women in VE, early, and non-expansion states, respectively, but aDDs were not statistically significant.

CONCLUSIONS

Prevalence of CRC and BC screening among low-income adults rose in Medicaid expansion states, though increases were significantly higher than those in non-expansion states only for recent CRC screening in VE expansion states. Large-scale improvements in cancer screening may take several years following expansion in access to care.

Evaluating the Cost-Effective Use of Follow-Up Colonoscopy Based on Screening Findings and Age

Introduction

Colorectal cancer (CRC), if not detected early, can be costly and detrimental to one's health. Colonoscopy can identify CRC early as well as prevent the disease. The benefit of screening colonoscopy has been established, but the optimal frequency of follow-up colonoscopy is unknown and may vary based on findings from colonoscopy screening and patient age.

Methods

A partially observed Markov process (POMP) was used to simulate the effects of follow-up colonoscopy on the development of CRC. The POMP uses adenoma and CRC growth models to calculate the probability of a patient having colorectal adenomas and CRC. Then, based on mortality, quality of life, and the costs associated with diagnosis, treatment, and surveillance of colorectal cancer, the overall costs and increase in quality-adjusted life years (QALYs) are calculated for follow-up colonoscopy scenarios.

Results

At the $100,000/QALY gained threshold, only one follow-up colonoscopy is cost-effective only after screening at age 50 years. The optimal follow-up is 8.5 years, which gives 84.0 QALYs gained/10,000 persons. No follow-up colonoscopy was cost-effective at the $50,000 and $75,000/QALY gained thresholds. The intervals were insensitive to the findings at screening colonoscopy.

Conclusion

Follow-up colonoscopy is cost-effective following screening at age 50 years but not if screening occurs later. Following screening at age 50 years, the optimal follow-up interval is close to the currently recommended 10 years for an average risk screening but does not vary by colonoscopy result.

What Happened to Disparities in CRC Screening Among FFS Medicare Enrollees Following Medicare Modernization?

The Medicare Modernization Act of 2003, implemented in 2006, increased managed care options for seniors. It introduced insurance plans for prescription drug coverage for all Medicare beneficiaries, whether they were enrolled in FFS or managed care (Medicare Advantage) plans. The availability of drug coverage beginning in 2006 served to free up budgets for FFS Medicare enrollees that could be used to make copayments for colorectal cancer (CRC) screening using endoscopy (colonoscopy or sigmoidoscopy). In 2007, Medicare eliminated the copayments required by seniors for CRC screening by endoscopy. Later in 2008, CRC screening by colonoscopy became part of the gold standard for CRC screening. This legitimized its use and offered even further encouragement to seniors, who may have been reluctant to undergo the procedure because of the non-pecuniary risks associated with it. In addition, 37 CRC screening interventions occurred during this timeframe to enhance compliance with screening standards. Using multilevel analysis of individuals' endoscopy utilization, derived from 100% FFS Medicare claims, along with county-level market and contextual factors, we compare the periods before and after the MMA (2001-2005 to 2006-2009) to determine whether disparities in the utilization of endoscopic CRC screening occurred or changed over the decade. We examined Blacks, Asians, and Hispanics relative to Whites, and Females relative to Males (with race or ethnicity combined). We examined each state separately for evidence of disparities within states, to avoid confounding by geographic disparities. We expected that the net effect of the policy changes and the targeted interventions over the decade would be to increase CRC screening by endoscopy, reducing disparities. We saw improvements over time (reduced disparities relative to Whites) for Blacks and Hispanics residing in several states, and improvements over time for Females relative to Males in many states. For the vast majority of states, however, disparities persisted with Whites and Males exhibiting greater rates of utilization than other groups. States that undertook the interventions were more likely to have had improvements in disparities or positive disparities for women and minorities. While some gains were made over this time period, the gains were unevenly distributed across the USA and more work needs to be done to reduce remaining disparities.

Medicare modernization and diffusion of endoscopy in FFS medicare

OBJECTIVE

To examine how FFS Medicare utilization of endoscopy procedures for colorectal cancer (CRC) screening changed after implementation of the Medicare Prescription Drug, Improvement, and Modernization Act (MMA) in 2006, which provided subsidized drug coverage and expanded the geographic availability of Medicare managed care plans across the US.

DATA SOURCES/STUDY SETTING

Using secondary data from 100% FFS Medicare enrollees, we analyzed endoscopy utilization during two intervals, 2001-2005 and 2006-2009.

STUDY DESIGN

We examined change in predictors of county-level endoscopy utilization rates based on a conceptual model of market supply and demand with spillovers from managed care practices. The equations for each period were estimated jointly in a spatial lag regression model that properly accounts for both place and time effects, allowing robust assessment of changes over time.

DATA COLLECTION/EXTRACTION METHODS

All Medicare FFS enrollees with both Parts A and B coverage who were age 65+, remained alive and living in the same state over the interval were included in the analyses. The later interval used a new cohort defined the same as the earlier interval. 100% Medicare denominator files were also used, providing county of address to use for county-level aggregation. The outcome variable was defined as county-level proportion of enrollees who ever used endoscopy over the interval.

PRINCIPAL FINDINGS

Endoscopy utilization by FFS Medicare increased, and became more accessible across the US. Medicare managed care plan spillovers onto FFS Medicare endoscopy utilization changed over time from a significant negative (restraining) effect in the early period to no significant effect by the later period.

CONCLUSIONS

The MMA eased budget constraints for seniors, making endoscopic CRC screening more affordable. The MMA policies also strengthened managed care business prospects, and enrollments in Medicare managed care escalated. The change in managed care spillover effects reflects the gradual acceptance of endoscopic CRC screening procedures, as they emerged as the gold standard during the period.

Risks of colorectal advanced neoplasia in young adults versus those of screening colonoscopy in patients aged 50 to 54 years

BACKGROUND AND AIM

The role of screening or diagnostic colonoscopy to detect advanced neoplasia in young cohorts of age < 50 is unclear. This study compared the risk of colorectal neoplasia in a young age cohort against that in 50-54s screening cohort.

METHODS

A multi-center retrospective study was conducted at 14 university hospitals to compare the detection rates of neoplasia and advanced neoplasia in screening or diagnostic colonoscopy in the young cohort of < 50s against those in screening colonoscopy in the 50-54s cohort.

RESULTS

Among 10 477 eligible subjects, 9765 subjects were enrolled after excluding 712 subjects. Advanced neoplasia detection rates in the young screening cohort was significantly lower than that in the 50-54s screening cohort (5.9% vs 9.3%, P < 0.001). Compared with 50-54s screening cohort, the risk of advanced neoplasia was significantly reduced by 23%, 53%, and 54% in the 45-49s, 40-44s, and 20-39s screening cohorts, respectively. The detection rates of advanced neoplasia in the young diagnostic cohort was 5.0%, which was much lower than 11.8% in 50-54s screening cohort (P < 0.001). Compared with the 50-54s screening cohort, the risk of advanced neoplasia was significantly reduced by 50%, 66%, and 71% in the 45-49s, 40-44s, and 20-39s diagnostic cohorts, respectively.

CONCLUSIONS

Colonoscopy to detect advanced neoplasia in young adults aged < 50 years should be reconsidered as their risk of advanced neoplasia on screening or diagnostic colonoscopy was much lower than those of 50-54s screening cohort; however, colonoscopy screening may be justified for high-risk 45-49s cohorts.

Evaluating Molecular Biomarkers for the Early Detection of Lung Cancer: When Is a Biomarker Ready for Clinical Use? An Official American Thoracic Society Policy Statement

BACKGROUND

Molecular biomarkers have the potential to improve the current state of early lung cancer detection. The goal of this project was to develop a policy statement that provides guidance about the level of evidence required to determine that a molecular biomarker, used to support early lung cancer detection, is appropriate for clinical use.

METHODS

An ad hoc project steering committee was formed, to include individuals with expertise in the early detection of lung cancer and molecular biomarker development, from inside and outside of the Assembly on Thoracic Oncology. Key questions, generated from the results of a survey of the project steering committee, were discussed at an in-person meeting. Results of the discussion were summarized in a policy statement that was circulated to the steering committee and revised multiple times to achieve consensus.

RESULTS

With a focus on the clinical applications of lung cancer screening and lung nodule evaluation, the policy statement outlines categories of results that should be reported in the early phases of molecular biomarker development, discusses the level of evidence that would support study of the clinical utility, describes the outcomes that should be proven to consider a molecular biomarker clinically useful, and suggests study designs capable of assessing these outcomes.

CONCLUSIONS

The application of molecular biomarkers to assist with the early detection of lung cancer has the potential to substantially improve our ability to select patients for lung cancer screening, and to assist with the characterization of indeterminate lung nodules. We have described relevant considerations and have suggested standards to apply when determining whether a molecular biomarker for the early detection of lung cancer is ready for clinical use.

Comparison of outcomes between symptomatic and asymptomatic patients with colorectal cancer: a propensity score-matched analysis of surgical invasiveness, medical costs and oncological outcomes

Background and aims

Whether asymptomatic patients with colorectal cancer (CRC) who are treated in hospitals show better outcomes than symptomatic patients with CRC still remains unknown. The aim of this study was to evaluate differences in clinical benefits following treatment in asymptomatic and symptomatic patients with CRC.

Methods

This study was a retrospective cohort analysis with data obtained from records. A cohort of 145 asymptomatic and 123 symptomatic patients who underwent CRC surgery between January 2009 and December 2011 was enrolled. To reduce bias in comparing outcomes, propensity score (PS) analysis was used for matching of patients in the symptomatic and asymptomatic groups based on clinicopathological factors. Surgical invasiveness, medical costs and oncological outcomes were examined by unadjusted and PS-matched analysis.

Results

Tumours in the symptomatic group were more often diagnosed in advanced stages compared with tumours in the asymptomatic group. Therefore, fewer symptomatic group patients underwent minimally invasive surgery. Short-term outcomes, including amount of blood loss, duration of postoperative hospital stay and perioperative medical costs, were significantly better in the asymptomatic group. Although overall survival was significantly better in the asymptomatic group, there was no significant difference between the groups when the patients were adjusted on the basis of PS.

Conclusions

Though this study was limited by the retrospective nature and small sample size, favourable outcomes in asymptomatic patients were due to the higher proportion of patients in this group who were diagnosed with CRC in earlier stages, due to participation in CRC screening programmes.

A Plasma-Based Protein Marker Panel for Colorectal Cancer Detection Identified by Multiplex Targeted Mass Spectrometry

Combining potential diagnostics markers might be necessary to achieve sufficient diagnostic test performance in a complex state such as cancer. Applying this philosophy, we have identified a 13-protein, blood-based classifier for the detection of colorectal cancer. Using mass spectrometry, we evaluated 187 proteins in a case-control study design with 274 samples and achieved a validation of 0.91 receiver operating characteristic area under the curve.

Quality measures for colonoscopy: where should we be in 2015?

Colonoscopy is an effective colorectal cancer (CRC) screening and prevention modality as evidenced by a 30-year decline in both incident colon cancers and CRC mortality in the USA. The USA is unique among the developed countries in its use of colonoscopy as the most common method to screen for CRC. Individual patients gain maximum value from their colonoscopy experience when they undergo a comfortable exam that is of highest quality, during which all polyps are found and removed safely and completely, where their physicians adhere to all appropriate guidelines and when they (or their insurance) pay a reasonable amount for their care. Colonoscopy "quality" publications to date have been focused on how to improve the individual physician's procedural results and this narrow focus has birthed an entire industry (usually based on entering data into a national registry) that is focused on demonstrating a physician's success in achieving a certain threshold performance metric that is usually (a) marginally related to true health outcomes, (b) can be captured from the myriad electronic medical records (EMR) in existence today, and (c) is attainable by most practicing gastroenterologists. Medical societies have worked diligently to link these registries and recognition programs to commercial or federal payer-based incentive funds. As health care reform drives massive consolidation of delivery systems and reimbursement moves toward population-level two-sided financial risk models, our current measurement infrastructure will become irrelevant. The focus on "value" and the Triple Aim will drive development of a radically different approach. The process by which individual gastroenterologists (or practices) demonstrate the value of colonoscopy as a colorectal cancer (CRC) prevention tool will change dramatically. Essentially, six measures will be reported by a health system: (1) percent of eligible population screened, (2) access to colonoscopy services, (3) complication rates, (4) patient experience scores, (5) episode (bundle) cost, and (6) frequency with which interval cancers occur after a colonoscopy exam (likely using a 3-year interval). Each gastroenterologist within a health system will be evaluated using familiar metrics (cecal intubation, withdrawal time, adenoma detection rate) but these results will likely be used internally to determine whether they are included in a provider network. If they continue to be used in commercial or government incentive programs, then the enterprise electronic medical record will be constructed to populate external programs directly. Population-level metrics (listed above) will determine whether higher cost provider networks (including academic health centers) who might deliver better health outcomes can compete successfully for regional market share with lower cost providers. This article will outline a plan for a health system initiative focused on provision of colonoscopy for CRC prevention; a plan that will help a group of gastroenterologists (whether employed within a health system or independent) demonstrate why they should be a preferred provider and whether they will survive and thrive in the coming world of accountable care.

Elimination of cost-sharing and receipt of screening for colorectal and breast cancer

BACKGROUND

The aim of the cost-sharing provision of the Patient Protection and Affordable Care Act (ACA) was to reduce financial barriers for preventive services, including screening for colorectal cancer (CRC) and breast cancer (BC) among privately and Medicare-insured individuals. Whether the provision has affected CRC and BC screening prevalence is unknown. The current study investigated whether CRC and BC screening prevalence among privately and Medicare-insured adults by socioeconomic status (SES) changed before and after the ACA.

METHODS

Data obtained from the National Health Interview Survey pertaining to privately and Medicare-insured adults from 2008 (before the ACA) and 2013 (after the ACA) were used. There were 15,786 adults aged 50 to 75 years in the CRC screening analysis and 14,530 women aged ≥40 years in the BC screening analysis. Changes in guideline-recommended screening between 2008 and 2013 by SES were expressed as the prevalence difference (PD) and 95% confidence interval (95% CI) adjusted for demographics, insurance, income, education, body mass index, and having a usual provider.

RESULTS

Overall, CRC screening prevalence increased from 57.3% to 61.2% between 2008 and 2013 (P<.001). Adjusted CRC screening prevalence during the corresponding period increased in low-income (PD, 5.9; 95% CI, 1.8 to 10.2), least-educated (PD, 7.2; 95% CI, 0.9 to 13.5), and Medicare-insured (PD, 6.2; 95% CI, 1.7 to 10.7) individuals, but not in high-income, most-educated, and privately insured respondents. BC screening remained unchanged overall (70.5% in 2008 vs 70.2% in 2013) and in the low SES groups.

CONCLUSIONS

Increases in CRC screening prevalence between 2008 and 2013 were confined to respondents with low SES. These findings may in part reflect the ACA's removal of financial barriers.

Costs and benefits of an organized fecal immunochemical test-based colorectal cancer screening program in the United States

BACKGROUND

Despite clear recommendations and evidence linking colorectal cancer screening to lower incidence and mortality, > 40% of adults are not up to date with screening. Existing domestic and international models of organized cancer screening programs have been effective in increasing screening rates. Implementing an organized, evidence-based, national screening program may be an effective approach to increasing screening rates.

METHODS

In the current study, the authors estimated the initial investment required and the cost per person screened of a nationwide fecal immunochemical test (FIT)-based colorectal cancer screening program among adults aged 50 years to 75 years.

RESULTS

The initial additional investment required was estimated at $277.9 to $318.2 million annually, with an estimated 8.7 to 9.4 million individuals screened at a cost of $32 to $39 per person screened. The program was estimated to prevent 2900 to 3100 deaths annually.

CONCLUSIONS

The results of the current study indicate that implementing a national screening program would make a substantial public health impact at a moderate cost per person screened. Results from this analysis may provide useful information for understanding the public health benefit of an organized screening delivery system and the potential resources required to implement a nationwide colorectal cancer screening program, and help guide decisions about program planning, design, and implementation.

Disparities in endoscopy use for colorectal cancer screening in the United States

It is well established that disparities exist for colorectal cancer (CRC) incidence rates and death. With screening, death from CRC may be considered a preventable occurrence. Endoscopy (flexible sigmoidoscopy and colonoscopy) is the only modality with therapeutic benefit of removal of pre-cancerous polyps. The Patient Protection and Affordable Care Act mandated that preventive screening services be covered, which includes endoscopy for colon cancer screening. Recent federal rules have eliminated cost sharing for polyp removal during screening colonoscopy in privately insured patients; however, this has not been mandated for Medicare patients. Understanding the current state of disparities in endoscopy use is important, as these policy changes will affect millions of patients. The purpose of this literature review was to summarize the known research on disparities in endoscopy use for colon cancer screening in the United States and highlight areas for future research.

Analysis of the benefits and costs of a national campaign to promote colorectal cancer screening: CDC's screen for life-national colorectal cancer action campaign

The Centers for Disease Control and Prevention's Screen for Life: National Colorectal Cancer Action Campaign (SFL) is one of the longest running national multimedia campaigns to promote colorectal cancer screening. Since its inception in 1999, no study has quantified the benefits and costs of SFL. We modeled the impact of SFL campaign on screening rates, assuming that the effect size would range from 0.5% to 10% of the unscreened population exposed to the campaign in the last 14 years. Given the estimated benefits of the campaign and costs, we calculated the cost per person screened (2012 dollars). We hypothesize that if 0.5% of the population exposed to campaign messages were screened for colorectal cancer, an additional 251,000 previously unscreened individuals would be screened. The average cost of SFL per person screened would be $2.44. On the other hand, if 10% of the population exposed to campaign messages were screened, an additional 5.01 million individuals would be screened. The average cost per person screened would be $0.12. Results indicate that SFL improves screening rates at a relatively low cost per person screened. The findings in this study provide an important starting point and benchmark for future research efforts to determine the benefits and costs of health communication campaigns to promote cancer prevention.

Review of economic evidence in the prevention and early detection of colorectal cancer

This paper aims to systematically review the cost-effectiveness evidence, and to provide a critical appraisal of the methods used in the model-based economic evaluation of CRC screening and subsequent surveillance. A search strategy was developed to capture relevant evidence published 1999-November 2012. Databases searched were MEDLINE, EMBASE, National Health Service Economic Evaluation (NHS EED), EconLit, and HTA. Full economic evaluations that considered costs and health outcomes of relevant intervention were included. Sixty-eight studies which used either cohort simulation or individual-level simulation were included. Follow-up strategies were mostly embedded in the screening model. Approximately 195 comparisons were made across different modalities; however, strategies modelled were often simplified due to insufficient evidence and comparators chosen insufficiently reflected current practice/recommendations. Studies used up-to-date evidence on the diagnostic test performance combined with outdated information on CRC treatments. Quality of life relating to follow-up surveillance is rare. Quality of life relating to CRC disease states was largely taken from a single study. Some studies omitted to say how identified adenomas or CRC were managed. Besides deterministic sensitivity analysis, probabilistic sensitivity analysis (PSA) was undertaken in some studies, but the distributions used for PSA were rarely reported or justified. The cost-effectiveness of follow-up strategies among people with confirmed adenomas are warranted in aiding evidence-informed decision making in response to the rapidly evolving technologies and rising expectations.

An evaluation of colonoscopy surveillance guidelines: are we actually adhering to the guidelines?

BACKGROUND

National guidelines put forth by the American Cancer Society, the US Multi-Society Task Force on Colorectal Cancer, and the American College of Gastroenterology provide recommendations regarding colorectal cancer screening and follow-up surveillance. Practice patterns may differ from these guidelines. This study analyzes the concordance between a tertiary equal access system and national guidelines for colorectal cancer and polyp surveillance.

METHODS

We performed a retrospective database review of all patients at a single institution undergoing screening colonoscopy from 2010 to 2011. Patient demographics, indication for colonoscopy, pathologic findings, and follow-up recommendations documented by the provider were analyzed. Multivariate analysis was performed in an attempt to identify predictors of discordant recommendations.

RESULTS

One thousand four hundred twenty patients were identified (mean age, 54.3 ± 7.7 years, 48.6% women). The gastroenterology service performed the majority of colonoscopies (87.2%) compared with the surgery service (11.6%). The major indications were routine screening (84.4%) and a strong family history of colorectal cancer (12.2%). The adenoma detection rate for the entire cohort was 27.4%. Other pathologic conditions identified included hyperplastic polyps (16%), lymphoid aggregates (3.5%), and invasive adenocarcinoma (0.1%). Overall, follow-up recommendations correlated with established guidelines in 97% of cases. By multivariate analysis, only the final pathologic finding of lymphoid aggregates was associated with discordant recommendations (odds ratio [OR], 4.62; 95% confidence interval [CI], 1.64 to 12.99; P = .004). When comparing discordant recommendations between specialties, there was a statistically significant difference between gastroenterology (1.6%) and surgery (7.6%) (P < .0001) providers; surgeons trended toward recommending earlier follow-up examinations (P = .37).

CONCLUSIONS

Overall, surveillance recommendations correlated well with current national guidelines. Concordance rates were higher with gastroenterologists in this cohort. Alterations based on final pathologic examination and individual cases remain clinically important.

Fecal calprotectin more accurately reflects endoscopic activity of ulcerative colitis than the Lichtiger Index, C-reactive protein, platelets, hemoglobin, and blood leukocytes

BACKGROUND

The correlation between noninvasive markers with endoscopic activity according to the modified Baron Index in patients with ulcerative colitis (UC) is unknown. We aimed to evaluate the correlation between endoscopic activity and fecal calprotectin (FC), C-reactive protein (CRP), hemoglobin, platelets, blood leukocytes, and the Lichtiger Index (clinical score).

METHODS

UC patients undergoing complete colonoscopy were prospectively enrolled and scored clinically and endoscopically. Samples from feces and blood were analyzed in UC patients and controls.

RESULTS

We enrolled 228 UC patients and 52 healthy controls. Endoscopic disease activity correlated best with FC (Spearman's rank correlation coefficient r = 0.821), followed by the Lichtiger Index (r = 0.682), CRP (r = 0.556), platelets (r = 0.488), blood leukocytes (r = 0.401), and hemoglobin (r = -0.388). FC was the only marker that could discriminate between different grades of endoscopic activity (grade 0, 16 [10-30] μg/g; grade 1, 35 [25-48] μg/g; grade 2, 102 [44-159] μg/g; grade 3, 235 [176-319] μg/g; grade 4, 611 [406-868] μg/g; P < 0.001 for discriminating the different grades). FC with a cutoff of 57 μg/g had a sensitivity of 91% and a specificity of 90% to detect endoscopically active disease (modified Baron Index ≥ 2).

CONCLUSIONS

FC correlated better with endoscopic disease activity than clinical activity, CRP, platelets, hemoglobin, and blood leukocytes. The strong correlation with endoscopic disease activity suggests that FC represents a useful biomarker for noninvasive monitoring of disease activity in UC patients.

Patients whose physicians recommend colonoscopy and those who follow through

BACKGROUND

More than half of eligible individuals are not up-to-date with colon cancer screening.

PURPOSE

To assess the characteristics of those who received a colonoscopy screening recommendation and those who followed the physician recommendation.

METHODS

Patient self-administered questionnaire and medical record review in 16 private family physician practices.

RESULTS

From 8372 patients invited to participate, 685 were enrolled and had a medical record review; 219 (32%) had a colonoscopy recommendation and 86 (39%) received a colonoscopy. Independent factors associated with having a recommendation for colonoscopy were significantly younger in age (odds ratios [OR] = 1.6), higher incomes (annual income ≥$40 000 vs <$40 000; OR = 1.8), physician or nurse discussion about colon cancer tests (OR = 1.6), physical visit in the preceding 26 months (OR = 1.7), distant relative with colon cancer (OR = 2.4), and a medical diagnosis of hyperlipidemia (OR = 2.1). Independent factors associated with following through on colonoscopy after a recommendation were age ≥65 years (OR = 0.3), male patient (OR = 0.4), and feeling that colon cancer screening is very important (OR = 3.2).

CONCLUSIONS

Socioeconomic factors are associated with receipt of a colonoscopy recommendation. Fewer than one third of patients had documentation of a physician colonoscopy recommendation and of those, less than half followed through.

Screening for colorectal cancer: what fits best?

Colorectal cancer (CRC) screening has been shown to be effective in reducing CRC incidence and mortality. There are currently a number of screening modalities available for implementation into a population-based CRC screening program. Each screening method offers different strengths but also possesses its own limitations as a population-based screening strategy. We review the current evidence base for accepted CRC screening tools and evaluate their merits alongside their challenges in fulfilling their role in the detection of CRC. We also aim to provide an outlook on the demands of a low-risk population-based CRC screening program with a view to providing insight as to which modality would best suit current and future needs.

A public-health perspective on screening colonoscopy

Colorectal cancer is an important global health problem. Randomized trials have shown that screening programs can reduce both colorectal cancer incidence and mortality, and guidelines strongly support screening. Nevertheless, screening rates are relatively low and concerted efforts are being made to increase screening uptake. Many guidelines and practitioners have come to view colonoscopy as the optimal screening strategy. Colonoscopy provides both a gold-standard diagnostic test and, with polypectomy, a therapeutic intervention that can prevent cancer. However, from a public-health perspective, emphasizing colonoscopy is problematic. The efficacy of colonoscopy has not been supported with randomized trial data, accuracy is imperfect, procedural quality is variable, complications are not uncommon, endoscopic capacity is limited, procedure costs are high, and many patients prefer alternative tests. Successful screening programs will need to provide a range of screening modalities and ensure that endoscopic resources are used efficiently.