Colon cancer incidence rates have dropped 30% in the U.S. in the last 10 years among adults 50 and older due to the widespread uptake of colonoscopy, with the largest decrease in people older than 65, according to a study.
Colonoscopy use has almost tripled among adults ages 50 to 75, from 19% in 2000 to 55% in 2010, researchers reported in Colorectal Cancer Statistics, 2014, published in the March/April issue of CA: A Cancer Journal for Clinicians.
The article and its companion report, Colorectal Cancer Facts & Figures, were released by American Cancer Society researchers as part of a new initiative by the National Colorectal Cancer Roundtable to increase screening rates to 80% by 2018.
Colorectal cancer the No. 3 most common cancer and the third-leading cause of cancer death in men and women in the U.S. Its slow growth from precancerous polyp to invasive cancer provides a rare opportunity to prevent cancer through the detection and removal of precancerous growths. Screening also allows early detection of cancer, when treatment is more successful, thus reducing colorectal cancer mortality both by decreasing the incidence of disease and by increasing the likelihood of survival.
Using incidence data from the National Cancer Institutes Surveillance, Epidemiology, and End Results program and the CDCs National Program of Cancer Registries, as provided by the North American Association of Central Cancer Registries, Rebecca Siegel, MPH, and colleagues found that overall incidence rates decreased by an average of 3.4% per year during 2001-10.
However, trends vary substantially by age. Rates declined by 3.9% per year among adults ages 50 and older but increased by 1.1% per year among men and women younger than 50. That increase was confined to tumors in the distal colon and rectum, patterns for which a rise in obesity and emergence of unfavorable dietary patterns have been implicated.
Most strikingly, the rate of decline has surged among those 65 and older, accelerating from a decrease of 3.6% per year during 2001-08 to 7.2% per year during 2008-10.
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.
Like incidence, mortality rates have declined most rapidly within the past decade. From 2001 to 2010, rates decreased by approximately 3% per year in both men and women, compared with declines of approximately 2% per year during the 1990s.
These continuing drops in incidence and mortality show the lifesaving potential of colon cancer screening; a potential that an estimated 23 million Americans between ages 50 and 75 are not benefiting from because they are not up to date on screening, Richard C. Wender, MD, American Cancer Society chief cancer control officer, said in a news release. Sustaining this hopeful trend will require concrete efforts to make sure all patients, particularly those who are economically disenfranchised, have access to screening and to the best care available.
The data is being released at the launch of a nationwide effort to increase colorectal cancer screening rates to 80% by 2018. The National Colorectal Cancer Roundtable, an organization co-founded by the American Cancer Society and the CDC, will focus on dramatically increasing colorectal cancer screening rates in the U.S. over the next four years and increasing awareness of the potential for early detection and prevention of this cancer.
Report access: www.cancer.org/cancer/news/news/report-more-colon-testing-leads-to-30-percent-drop-in-cancer-rates