Colorectal Cancer Incidence and Screening — United States, 2008 and 2010

C. Brooke Steele, DO

Sun Hee Rim, MPH

Djenaba A. Joseph, MD

Jessica B. King, MPH

Laura C. Seeff, MD

National Center for Chronic Disease Prevention and Health Promotion, CDC

Corresponding author: C. Brooke Steele, Division of Cancer Prevention and Control, CDC. Telephone: 770-488-4261; E-mail: BSteele1@cdc.gov.

Introduction

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the United States among cancers that affect both men and women (1). Screening for CRC reduces incidence and mortality (2). In 2008, the U.S. Preventive Services Task Force (USPSTF) recommended that persons aged 50–75 years at average risk for CRC be screened for the disease by using one or more of the following methods: fecal occult blood testing (FOBT) every year, sigmoidoscopy every 5 years (with high-sensitivity FOBT every 3 years), or colonoscopy every 10 years (2).

This report is part of the second CDC Health Disparities and Inequalities Report (CHDIR). The 2011 CHDIR (3) was the first CDC report to assess disparities across a wide range of diseases, behavior risk factors, environmental exposures, social determinants, and health-care access. The topic presented in this report is based on criteria that are described in the 2013 CHDIR Introduction (4). This report updates information regarding CRC screening provided in the 2011 CHDIR (5). The purposes of this report are to discuss and raise awareness of differences in colorectal cancer incidence, mortality, and screening and to prompt actions to reduce these disparities.

Methods

To characterize disparities for CRC incidence, CRC death rates, and CRC screening test use by test type, CDC analyzed data from multiple sources and years. Different analytic approaches were used to characterize disparities depending on the data source (i.e., deviation from referent group or comparison of weighted estimates and confidence intervals [CIs]).

To describe CRC incidence and death rates, CDC analyzed 2008 CRC incidence and mortality data from U.S. Cancer Statistics (USCS) (1). Demographic characteristics analyzed included sex, age, race and ethnicity. Data on household income and educational attainment are not collected by cancer registries. Race was classified as non-Hispanic white, non-Hispanic black, Asian/Pacific Islander, or American Indian/Alaska Native. Ethnicity was classified as Hispanic or non-Hispanic; persons of Hispanic ethnicity might be of any race or combination of races. Incidence data were drawn from CDC's National Program of Cancer Registries (NPCR) and the National Cancer Institute's Surveillance, Epidemiology, and End Results Program (SEER) registries that met U.S. Cancer Statistics publication criteria for the diagnosis year 2008, and mortality data were derived from the National Vital Statistics System. In 2008, all 50 states and the District of Columbia had high-quality incidence and mortality data available, and thus 100% of the U.S. population is represented for both. Incident CRCs were coded* according to the International Classification of Diseases for Oncology, Third Edition (ICD-O-3). All death certificates with CRC identified as the underlying cause of death according to the International Classification of Diseases, Tenth Revision (ICD-10) during 2008 were included in this analysis. Incidence and death rates were calculated for all age groups using SEER*Stat software (version 7.04); rates were reported per 100,000 population. Data were age-adjusted to the 2000 U.S. standard population by the direct method; corresponding 95% CIs were calculated as modified gamma intervals (6).

Disparities were measured as the deviations from a "referent" category rate. Absolute difference was measured as the simple difference between a population subgroup estimate and the estimate for its respective reference group. The relative difference, a percentage, was calculated by dividing the difference by the value in the referent category and multiplying by 100.

To assess disparities in CRC screening test use by test type, CDC analyzed 2010 survey data from the Behavioral Risk Factor Surveillance System (BRFSS). BRFSS is a state-based, random digit-dialed telephone survey of the noninstitutionalized, U.S. civilian population aged ≥18 years (7). Survey data were available for all 50 states and the District of Columbia. In 2010, the median response rate was 54.6%, and the median cooperation rate was 76.9% (7). Respondents who refused to answer, had a missing answer, or did not know the answer to a question were excluded from analysis of that specific question. Of the 226,205 persons aged 50–75 years who responded in 2010, approximately 4.2% were excluded from the analyses.

Demographic characteristics from BRFSS that were analyzed included sex, age, race, ethnicity, educational attainment, income level, disability status, health insurance status, and geographic location. Race was classified as non-Hispanic white, non-Hispanic black, Asian/Pacific Islander, American Indian/Alaska Native, or other non-Hispanic. Ethnicity was classified as Hispanic or non-Hispanic; persons of Hispanic ethnicity might be of any race or combination of races. Educational attainment was classified as less than high school, some high school, high school graduate or equivalent, some college/technical school, or college graduate. Income level was classified as <$15,000, $15,000–$34,999, $35,000–$49,999, $50,000–$74,999, and ≥$75,000.The median response rate† and the median cooperation rate§ are based on Council of American Survey and Research Organizations guidelines (available at http://www.cdc.gov/brfss/annual_data/annual_2010.htm).

BRFSS respondents aged 50–75 years, the age group for which USPSTF recommends CRC screening, were asked if they had ever used a "special kit at home to determine whether the stool contains blood (FOBT)," whether they had ever had "a tube inserted into the rectum to view the colon for signs of cancer or other health problems (sigmoidoscopy or colonoscopy)," and when these tests were last performed. To allow assessment of up-to-date screening according to current USPSTF guidelines, the measure of overall screening prevalence used in the 2011 CHDIR (5) was modified. Percentages were estimated for persons aged 50–75 years who reported receiving an FOBT within 1 year, a sigmoidoscopy within 5 years with FOBT within 3 years, or a colonoscopy within 10 years preceding the survey. Data for the three recommended test options were combined to estimate overall prevalence of up-to-date CRC screening. States were categorized into four poverty quartiles by using data from the 2010 Current Population Survey (available at http://cps.ipums.org/cps), and composite screening rates per quartile were calculated. Composite percentages and 95% CIs were calculated by selected characteristics. Data were weighted according to the sex, racial/ethnic, and age distribution of the adult population of each state by using intercensal estimates and were age standardized to the 2010 BRFSS population aged 50–75 years.

Results

Compared with women, men had higher CRC incidence rates (51.6 versus 38.7 per 100,000 population) and death rates (19.7 vs. 13.8 per 100,000 population) in 2008 (Table 1). CRC incidence and mortality increased with advancing age (Figure). Incidence and death rates were highest among persons aged ≥75 years. Non-Hispanic blacks had higher CRC incidence and death rates than non-Hispanic whites, Asians/Pacific Islanders, and American Indians/Alaska Natives. Incidence and death rates were higher among non-Hispanics than among Hispanics.

In 2010, among respondents aged 50–75 years, 64.5% reported being up-to-date with CRC screening (Table 2). The proportion of respondents who reported having had any of the test options was greater among persons aged 65–75 years compared with those aged 50–64 years, among non-Hispanics compared with Hispanics, among persons with a disability compared with those with no disability, and among persons with health insurance compared with those with no health insurance. This disparity in reported test use by health insurance status was evident for all three test types (FOBT, sigmoidoscopy with FOBT, and colonoscopy). The proportions for colonoscopy use and for overall CRC screening were slightly greater among women than among men. Reported rates of test use increased with increasing education level and household income, with the greatest increases occurring among those who reported having had a colonoscopy within 10 years preceding the survey. The prevalence of respondents who were up-to-date with CRC screening was highest among non-Hispanic whites (66.4%), followed closely by non-Hispanic blacks (64.8%). Non-Hispanic whites had the greatest proportion of respondents reporting having had a colonoscopy within 10 years preceding the survey compared with all other races; non-Hispanic blacks had the greatest proportion of respondents reporting having had FOBT within the year preceding the survey.

By composite state poverty quartiles, the relationship between reported screening rates and poverty varied by test type. No consistent relationship was observed between poverty and reported use of FOBT; however, the number of respondents who reported use of FOBT testing was small (Table 3). An inverse relationship was observed for reported use of colonoscopy and poverty, with reported colonoscopy use generally decreasing with increasing levels of poverty (Table 3).

Discussion

CRC incidence and death rates were higher among older, male, and non-Hispanic populations. CRC incidence and death rates for many of these groups exceeded Healthy People 2020 targets of 38.6 new CRC cases per 100,000 population and 14.5 CRC deaths per 100,000 population (8). Progress in reducing deaths from CRC has been achieved through a combination of primary prevention, early detection, and treatment (9). In 2010, approximately two thirds of the U.S. population aged 50–75 years met USPSTF criteria for up-to-date CRC screening. The proportion screened in a timely manner varied by race and other demographic characteristics.

Although estimates of the overall prevalence of up-to-date CRC screening in this report and in the 2011 report were computed differently, certain patterns were similar. The 2011 report analyzed BRFSS data for 2002–2008. During that time period, non-Hispanic whites had the highest overall prevalence of CRC screening, followed closely by non-Hispanic blacks (3). The same finding was observed in 2010. American Indians/Alaska Natives and Hispanics had lower CRC screening rates in 2002–2008 than non-Hispanic blacks. This disparity persisted in 2010. The pattern was less consistent for the Asian/Pacific Islander population; in 2002 and 2004, their overall prevalence of up-to-date CRC screening was substantially lower than the prevalence for non-Hispanic whites. The gap narrowed in 2006 and 2008 but widened in 2010.

In 2010, CRC screening test use increased with age, educational level, and household income level. The demographic disparities were greater for colonoscopy than for sigmoidoscopy and FOBT. Similar findings were reported in the 2011 report (3) and in other previous studies (10–12). Having health insurance is also a strong predictor of screening for colorectal cancer (11,13,14). Disparities in the overall prevalence of up-to-date CRC screening by health insurance status were observed in 2008 (5) and 2010. Screening rates among insured respondents were 66.6 in 2008 and 67.5 in 2010. Rates among uninsured respondents were 37.5 in 2008 and 35.4 in 2010. Medicare has covered CRC screening for enrollees since 2001. Although this expansion of cancer screening coverage has increased CRC screening among older persons, persistent racial/ethnic, socioeconomic, and geographic disparities in test use have been reported among persons aged ≥65 years (15–17). Among younger adults, those with lower incomes and less than a high school education are less likely to have health-care insurance than those with higher incomes and at least some college education (18). For many patients, implementation of the Affordable Care Act has removed financial barriers to CRC screening by mandating that nongovernmental health plans cover certain preventive health services without cost-sharing requirements (19).

FOBT and sigmoidoscopy screening rates were low in 2010. Previous studies have noted a continued decline in use of these tests (12,20–22), despite the fact that screening with each has been reported to be associated with reduced mortality from CRC (23,24). Some primary care physicians perceive FOBT and sigmoidoscopy to be less effective in reducing CRC mortality than colonoscopy, which might influence which tests they recommend to their patients (25–27). Studies indicate that some patients prefer FOBT, and discordance between physician and patient preferences might affect uptake of CRC screening (28–30). Discussing multiple options for CRC screening with patients and acknowledging their preferences when recommendations are made could contribute to improved completion of testing.

State-level poverty percentages were less clearly associated with use of FOBT compared with colonoscopy. During 2002–2008, screening with annual FOBT or lower endoscopy within 10 years was related to both income and state poverty levels (3). In previous studies of trends in CRC screening, changes in FOBT and colonoscopy use varied substantially by income level, health insurance status, race/ethnicity, and other demographic characteristics (31,32). Additional studies are needed to investigate the effects of poverty and sociocultural indicators on test use, independent of insurance status.

CDC has funded activities to improve CRC screening rates, including efforts to increase access to screening for underserved populations. The Colorectal Cancer Control Program (CRCCP) was established in 2009 following the successful implementation of a CRC screening demonstration program in five sites across the country (33). CRCCP funds 25 states and four tribes, with the goal of increasing screening rates among those aged 50–75 years to 80% in funded states (http://www.cdc.gov/cancer/colorectal). Approximately one third of funds are used to provide direct screening services and follow-up care to low-income men and women aged 50–64 years who are underinsured or uninsured. The majority of funds are used to promote and implement evidence-based strategies recommended by the Task Force on Community Preventive Services (http://www.thecommunityguide.org/index.html) to increase population-level CRC screening. Funded states and tribes are encouraged to partner with health-care systems, insurers, worksites, and others to maximize the impact of implemented interventions. To date, all funded states and tribes have implemented at least one evidence-based intervention, with the majority implementing two or more. Grantees have partnered with federally qualified health centers (i.e., organizations that receive grants under Section 330 of the Public Health Service act) and private and nonprofit health-care systems to implement patient navigation programs and interventions to reduce structural barriers to screening, with private health insurers and state Medicaid offices to implement provider and patient reminder systems, and with comprehensive cancer control coalitions and local health departments to implement small media campaigns.

CDC also funds the National Comprehensive Cancer Control Program (NCCCP), which provides support to all 50 states and the District of Columbia, seven tribes/tribal organizations, and seven U.S.-associated Pacific Islands/Territories to establish partnerships, determine priorities, and create and implement cancer plans to reduce the burden of cancer in their communities (34). Activities that have been implemented successfully by selected NCCCP programs to reduce the burden of CRC have included initiation of professional education and practice improvement initiatives for primary care providers and collaboration with community-based organizations to promote CRC prevention (35). Many grantees also have made the elimination of health disparities a priority. Some include goals and objectives to improve cancer prevention, early detection, treatment, and survivorship care among disparate populations in their cancer plans (http://cancercontrolplanet.cancer.gov).

Limitations

The findings in this report are subject to at least six limitations. First, cancer registries have an interval of approximately 24 months after the close of the diagnosis year to submit cases to NPCR and SEER, which affects the timely calculation of cancer incidence rates. The mose recent year for which incidence data were available for this report was 2008. Second, variation in the quality of race and ethnicity information in medical records and death certificates (36,37) could influence the accuracy of surveillance data. Third, BRFSS results might underestimate or overestimate actual CRC screening test rates because BRFSS does not determine the indication for the test (screening versus diagnostic use) or whether the tests are conducted according to timelines recommended in CRC screening guidelines. Fourth, because BRFSS does not collect information from persons in institutions, nursing homes, long-term–care facilities, military installations, and correctional institutions, the results cannot be generalized to these populations. Fifth, BRFSS responses are self-reports and not validated by medical record or claims data review. Finally, participation rates for random-digit-dialed health surveys have been decreasing. However, although BRFSS has a low median response rate, the BRFSS weighting procedure partially corrects for nonresponse.

Conclusion

Disparities in CRC incidence, mortality, and screening persist. CRC incidence and death rates have decreased among adults in the United States since 1999 (38). However, men have higher rates of both incidence and mortality than women, and non-Hispanic blacks have higher rates than other racial and ethnic groups (1). Although increased screening could reduce mortality from CRC by an estimated 50% (9), the prevalence of up-to-date screening according to USPSTF guidelines among Asians/Pacific Islanders and American Indians/Alaska Natives remains lower than the prevalence for other racial and ethnic groups. Coordinated and systems-focused efforts by CDC and other federal agencies, state and local health departments, and the medical community to address barriers to end disparities in CRC screening should continue so that the incidence and mortality associated with this disease can be reduced among all populations.

Acknowledgment

Kristine Gerdes, EdS, MPH, Division of Public Affairs, Office of the Associate Director of Communication, CDC, provided assistance with this report.

References

1. US Cancer Statistics Working Group. United States cancer statistics: 1999–2008 incidence and mortality web-based report. Atlanta, GA: US Department of Health and Human Services, CDC, National Cancer Institute; 2011. Available at http://www.cdc.gov/uscs.
2. Zauber AG, Landsdorp-Vogelaar I, Knudson AB, et al. Evaluating test strategies for colorectal cancer screening: a decision analysis for the U.S. Preventive Services Task Force. Ann Int Med 2008;14:659–69.
3. CDC. CDC health disparities and inequalities report—United States, 2011. MMWR 2011;60(Suppl; January 14, 2011).
4. CDC. Introduction. In: CDC health disparities and inequalities report—United States, 2013. MMWR 2013;62(No. Suppl 3).
5. CDC. Cncer scolorectal careening—United States, 2002, 2004, 2006, 2008. In: CDC health disparities and inequalities report—United States, 2011. MMWR 2011;60(Suppl; January 14, 2011).
6. Tiwari RC, Clegg LX, Zou Z. Efficient interval estimation of age-adjusted cancer rates. Stat Methods Med Res 2006;15:547–69.
7. CDC. Behavioral Risk Factor Surveillance System. Atlanta, GA: US Department of Health and Human Services, CDC; 2010. Available at http://www.cdc.gov/brfss.
8. US Department of Health and Human Services. Healthy people 2020 topics and objectives: cancer. Washington, DC: US Department of Health and Human Services; 2011. Available at http://www.healthypeople.gov/2020/topicsobjectives2020/objectiveslist.aspx?topicId=5.
9. Edwards BK, Ward E, Kohler BA, et al. Annual report to the nation on the status of cancer, 1975–2006, featuring colorectal cancer trends and impact of interventions (risk factors, screening, and treatment) to reduce future rates. Cancer 2010;116:544–73.
10. CDC. Cancer screening—United States, 2010. MMWR 2012;61:41–5.
11. Shapiro JA, Seeff LC, Thompson, et al. Colorectal cancer test use from the 2005 National Health Information Survey. Cancer Epidemiol Biomarkers Prev 2008;17:1623–30.
12. CDC. Prevalence of colorectal cancer screening among adults—Behavioral Risk Factor Surveillance System, United States, 2010. MMWR 2012;61:51–6.
13. Doubeni CA, Laiyemo AO, Young AC, et al. Primary care, economic barriers to health care, and use of colorectal cancer screening tests among Medicare enrollees over time. Ann Fam Med 2010;8:299–307.
14. Beydoun HA, Beydoun MA. Predictors of colorectal cancer screening behaviors among average-risk older adults in the United States. Cancer Causes Control 2008;19:339–59.
15. White A, Vernon SW, Franzini L, Du XL. Racial and ethnic disparities in colorectal cancer screening persisted despite expansion of Medicare's screening reimbursement. Cancer Epidemiol Biomarkers Prev 2011;20:811–7.
16. Semrad JJ, Tancredi DJ, Baldwin LM, Green P, Fenton JJ. Geographic variation of racial/ethnic disparities in colorectal cancer testing among Medicare enrollees. Cancer 2011;117:1755–63.
17. Doubeni CA, Laivemo AO, Reed G, Field TS, Fletcher RH. Socioeconomic and racial patterns of colorectal cancer screening among Medicare enrollees in 2000 to 2005. Cancer Epidemiol Biomarkers Prev 2009;18:2170–5.
18. Agency for Healthcare Research and Quality. National healthcare disparities report: 2011. Washington, DC: US Department of Health and Human Services, Agency for Healthcare Research and Quality; 2012. Available at http://www.ahrq.gov/qual/nhdr11/chap9.htm.
19. Skopec L, Sommers BD. Seventy-one million additional Americans are receiving preventive services coverage without cost-sharing under the Affordable Care Act. Washington, DC: US Department of Health and Human Services; 2013. Available at http://aspe.hhs.gov/health/reports/2013/PreventiveServices/ib_prevention.cfm.
20. Klabunde CN, Lanier D, Nadel MR, et al. Colorectal cancer screening by primary care physicians: recommendations and practices, 2006–2007. Am J Prev Med 2009;37:8–16.
21. Meissner HI, Breen N, Klabunde CN, Vernon SW. Patterns of colorectal cancer screening uptake among men and women in the United States. Cancer Epidemiol Biomarkers 2006;15:389–94.
22. Schenck AP, Peacock S, Klabunde CN, et al. Trends in colorectal cancer test use in the Medicare population, 1998–2005. Am J Prev Med 2009;37:1–7.
23. Whitlock EP, Lin J, Liles E, et al. Screening for colorectal cancer: an updated systematic review. Rockville, MD: US Department of Health and Human Services, Agency for Healthcare Research and Quality; 2008.
24. Schoen RE, Pinksky PF, Weissfeld JL, et al. Colorectal-cancer incidence and mortality with screening flexible sigmoidoscopy. New Engl J Med 2012;366:2345–57.
25. Feldstein AC, Perrin N, Liles EG, et al. Primary care colorectal cancer screening recommendation patterns: associated factors and screening outcomes. Med Decis Making 2012;32:198–208.
26. Yabroff KR, Klabunde CN, Yuan G, et al. Are physicians' recommendations for colorectal cancer screening guideline-consistent? J Gen Intern Med 2010;26:177–84.
27. Zapka JM, Klabunde CN, Arora NK, et al. Physicians' colorectal cancer screening discussion and recommendation patterns. Cancer Epidemiol Biomarkers Prev 2011;20:509–21.
28. Inadomi JM, Vijan S, Janz NK, et al. Adherence to colorectal cancer screening: a randomized clinical trial of competing strategies. Arch Intern Med 2012;172:575–82.
29. Hawely ST, McQueen A, Bartholomew LK, et al. Preferences for colorectal cancer screening tests and screening test use in a large multispecialty primary care practice. Cancer 2012;118:2726–34.
30. Hawley ST, Volk RJ, Krishnamurthy P, et al. Preferences for colorectal cancer screening among racially/ethnically diverse primary care patients. Med Care 2008;46:S10–6.
31. Bandi P, Cokkinides V, Smith RA, Jemal A. Trends in colorectal cancer screening with home-based fecal occult blood tests in adults ages 50 to 64 years, 2000 to 2008. Cancer 2012;118:5092–9.
32. Klabunde CN, Cronin KA, Breen N, et al. Trends in colorectal cancer test use among vulnerable populations in the United States. Cancer Epidemiol Biomarkers Prev 2011;20:1611–21.
33. CDC. Colorectal Cancer Control Program. Atlanta, GA: US Department of Health and Health Services, CDC; 2010. Available at http://www.cdc.gov/cancer/crccp/about.htm.
34. CDC. National Comprehensive Cancer Control Program. Atlanta, GA: US Department of Health and Human Services, CDC; 2012. Available at http://www.cdc.gov/cancer/ncccp/about.htm.
35. CDC. National Comprehensive Cancer Control Program. Success stories. Atlanta, GA: US Department of Health and Human Services, CDC; 2012. Available at http://www.cdc.gov/cancer/ncccp/state.htm.
36. Clegg LX, Reichman ME, Hankey BF, et al. Quality of race, Hispanic ethnicity, and immigrant status in population-based cancer registry data: implications for health disparity studies. Cancer Causes Control 2007;18:177–87.
37. Arias E, Schauman WS, Eschbach K, Sorlie P, Backlund E. The validity of race and Hispanic origin on death certificates in the United States. Vital Health Stat 2008;148:1–23.
38. Eheman C, Henley SJ, Ballard-Barbash R, et al. Annual report to the nation on the status of cancer, 1975–2008, featuring cancers associated with excess weight and lack of sufficient physical activity. Cancer 2012;118:2338–66.