Colorectal Cancer Screening

Early Detection

On this page:

• Benefits of Screening Tests for Colorectal Cancer
• Measure
• Period
• Trends
• Most Recent Estimates
• Healthy People 2010 Targets
• Groups at High Risk for Not Being Screened
• Key Issues
• Additional Information on Colorectal Cancer Screening

Benefits of Screening Tests for Colorectal Cancer

Research supports the use of several screening tests for colorectal cancer. Usage is monitored by total test use and the following two specific tests:

• Fecal occult blood test (FOBT). When done every 1 to 2 years using home test kits in people aged 50 to 80, the FOBT can decrease the number of deaths due to colorectal cancer.
• Colorectal endoscopy (sigmoidoscopy or colonoscopy). Regular sigmoidoscopy can reduce colorectal cancer deaths. More research is needed to learn the best timing between exams and to determine the effectiveness of screening by colonoscopy. Colonoscopy also is the diagnostic procedure used to follow up positive FOBT and sigmoidoscopy screening tests.
  
  (Note: The 1987 and 1992 versions of the National Health Interview Survey asked only about proctoscopy use. Due to improvements in colorectal cancer screening technology and because sigmoidoscopy and colonoscopy are now recommended for colorectal cancer screening by major expert groups and covered by Medicare, respondents to the 2000 National Health Interview Survey were asked whether they had had a proctoscopy, sigmoidoscopy, or colonoscopy. The procedures are referred to collectively in this report as colorectal endoscopy.)

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Measure

FOBT: Percentage of adults aged 50 and older who reported that they had a fecal occult blood test (FOBT) within the past 2 years, by racial/ethnic group. In the 2000 National Health Interview Survey (NHIS), questions were asked on both home and office FOBT, and in 2003 questions were asked only on home FOBT. Responses from the 2000–2005 NHIS for home FOBT are directly calculated.

(Note: Responses from the 1987–1998 NHIS may under represent use of home FOBT because, starting in 2000, respondents were asked when—but not where—their most recent home blood stool test was. Before 2000, respondents were asked when their most recent blood stool test was and whether it was a home or office test. If a home and office test were both received within the past 2 years and the office test was the more recent, the response would be counted in the 2000 and later surveys and not in the pre-2000 surveys.)

Colorectal endoscopy: Percentage of adults aged 50 and older who reported that they ever had an endoscopy (proctoscopy, sigmoidoscopy, or colonoscopy).

Colorectal cancer test use: Percentage of adults aged 50 and older who had a colorectal cancer test (home-based FOBT in the last 2 years and/or ever had a colorectal endoscopy).

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Period – 1987–2005

Note: The most recent (2008) data are currently being reviewed. This section will be updated once research results have been published.

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Trends

Home FOBT: Decline. Home FOBT had been rising until 2000, then began falling in Whites, continued to rise in Blacks and Hispanics until 2003, then falling in these groups in 2005.

Colorectal endoscopy: Rising overall. Colorectal endoscopy had been rising from 1987–1998, stabilized until 2000, then began to rise again after 2000 and rose especially rapidly (Annual Percent Change = 7 percent) from 2003–2005. These same trends characterize both Whites and Blacks. Among Hispanics, rates  were slightly higher in 2005 than in 1992.

Colorectal cancer test use: Rising  overall. Rising, especially from 1987–1992, 1998–2000, and 2003–2005. Since 1987, colorectal cancer test use has been rising among Whites. Overall, rise among Blacks was attributable to large significant increases from 1987–1992 and 1998–2000. After a large rise among Hispanics from 1987–1992, the trend has been stable. Among Asians interviewed in California only, rates were stable from 2001–2003 (not graphed).

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Most Recent Estimates

In 2005, 25 percent of people aged 50 and older had a home FOBT within the past 2 years. This includes 18 percent of Hispanics, 24 percent of Blacks, and 26 percent of Whites. Among Asian women interviewed in California, 22 percent had a home FOBT within the past 2 years. In 2005, 50 percent of people 50 and older had ever had a colorectal endoscopy. This includes 32 percent of Hispanics, 43 percent of Blacks, and 53 percent of Whites. Among Asian women interviewed in California, 53 percent had ever had a colorectal endoscopy. In 2005, 59 percent of people 50 and older had used a colorectal cancer test. This includes 40 percent of Hispanics, 52 percent of Blacks, and 61 percent of Whites. Among Asian women interviewed in California, 60 percent had used a colorectal cancer test.

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Healthy People 2010 Targets

Increase to 50 percent the proportion of adults aged 50 and older who have had an FOBT within the past 2 years.

Increase to 50 percent the proportion of adults aged 50 and older who have ever had a sigmoidoscopy. Since colonoscopy use has eclipsed sigmoidoscopy use over the decade, we examined colonoscopy and sigmoidoscopy jointly. The target of 50% was met (for endoscopy including colonoscopy and sigmoidoscopy) in 2005.

No Healthy People 2010 target has been set for the proportion of adults who should receive colonoscopy screenings.

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Groups at High Risk for Not Being Screened

Immigrants and those with lower incomes, with less education, without insurance, and lacking a usual health care provider are less likely to be screened for colorectal cancer.

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Key Issues

Despite some improvements over time, colorectal cancer screening rates remain low. Understanding and overcoming doctor and patient barriers to these life-saving tests is critical.

Newer screening methods, such as virtual colonoscopy and fecal DNA testing, are promising and need further evaluation.

A substantial proportion of reported FOBT and colorectal endoscopy procedures may be used for diagnostic rather than screening purposes.

Different organizations have generated different guidelines. To see guidelines issued by the U.S. Preventive Services Task Force and others, go to http://www.ahrq.gov/clinic/USpstfix.htm. The Guide to Community Preventive Services, http://www.thecommunityguide.org/index.html , is a source of information about evidence-based approaches for enhancing cancer screening.

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Additional Information on Colorectal Cancer Screening

• Agency for Healthcare Research and Quality, Staying Healthy
  http://www.ahrq.gov/consumer/healthy.html
• The Annual Report to the Nation on the Status of Cancer, 1973-1997, with a Special Section on Colorectal Cancer (ACS)
  http://www3.interscience.wiley.com/cgi-bin/fulltext/75504286/HTMLSTART
• Cancer Intervention Surveillance Network (CISNET), Colorectal Cancer Mortality Projections
  http://cisnet.cancer.gov/projections/colorectal
• Colorectal Cancer (PDQ®): Screening — Health Professionals
  http://www.cancer.gov/cancerinfo/pdq/screening/colorectal/healthprofessional
• Colorectal Cancer Testing in the Medicare Population: 1998–2004
  
• http://www2.thecarolinascenter.org/crc/crc.aspx?tabid=229
• Guide to Community Preventive Services
  http://www.thecommunityguide.org/index.html
• Healthy People 2010, Volume 1, Chapter 3—Cancer
  http://www.health.gov/healthypeople/document/HTML/Volume1/03Cancer.htm
• National Cancer Institute, Colorectal Cancer Screening: Questions and Answers
  http://www.cancer.gov/cancertopics/factsheet/Detection/colorectal-screening
• National Health Interview Survey (NHIS) (NCHS)
  http://www.cdc.gov/nchs/nhis.htm
• State Cancer Profiles, Latest Rates, Percents, and Counts
  http://statecancerprofiles.cancer.gov/micromaps/
• U.S. Preventive Services Task Force Recommendations (ARHQ)
  http://www.ahrq.gov/clinic/uspstf/uspscolo.htm

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Next: Diagnosis

Page last reviewed: April 15, 2010