Colorectal Cancer Rates on the Decline

The incidence of colorectal cancer in the United States dropped by 30% between 2000 and 2010 among adults ages 50 and older, according to a recent report in CA: A Cancer Journal for Clinicians. The report's authors attribute the decline primarily to widespread use of colonoscopy, during which precancerous polyps can be detected and removed before they become cancerous.

Using data from the NCI's Surveillance, Epidemiology, and End Results program and the Centers for Disease Control and Prevention (CDC), the researchers found that the overall incidence of colorectal cancer decreased by an average of 3.4% per year during the decade. However, the trend varied by age, with incidence dropping by 3.9% among adults ages 50 and older but increasing by 1.1% per year among those younger than 50.

Most strikingly, the rate of decline surged among adults 65 and older, with the decline accelerating from 3.6% per year from 2001 to 2008 to 7.2% per year from 2008 to 2010. The “larger declines among Medicare-eligible seniors likely reflect higher rates of screening because of universal insurance coverage,” the authors wrote. “In 2010, 55% of adults aged 50 to 64 years reported having undergone a recent colorectal cancer screening test, compared with 64% of those aged 65 years and older.”

To continue the downward trend in colorectal cancer incidence, the National Colorectal Cancer Roundtable (NCCRT), an organization founded by the American Cancer Society and the CDC, has launched an initiative called “80% by 2018” in an effort to screen at least 80% of U.S. adults, according to current screening guidelines, within the next 4 years.

In announcing the effort last month, Richard Wender, MD, chair of the NCCRT and chief cancer control officer for the American Cancer Society, noted that “it's truly a national initiative, in which dozens of organizations have made a commitment to substantially eliminate colorectal cancer as a major public health problem.” So far, 89 organizations have pledged to help people get screened.

Speaking as part of the NCCRT announcement, U.S. Rep. Donald Payne Jr. of New Jersey said that screening 80% of adults is “a lofty but attainable goal” and one that might spare families tremendous pain. “My father wasn't screened early enough to save his life,” Payne added.

According to the report, only about 40% of colorectal cancer patients are diagnosed when the disease is still localized. More than 90% of patients diagnosed at that stage survive at least 5 years. That rate declines to 70.4% and 12.5% for patients diagnosed with regional and distant-stage disease, respectively.

Also troubling, according to the report, is that colorectal cancer incidence and mortality rates vary substantially by race and ethnicity. Among both men and women, rates are highest in blacks and lowest in Asian/Pacific Islanders. From 2006 to 2010, incidence rates were about 25% higher in blacks than in whites. The disparity in mortality rates is even greater: Blacks are 50% more likely to die of the disease than whites, largely due to lower socioeconomic status, the report says.