Study: Colon Cancer Rates Decrease Sharply in Older Americans
Growing use of colonoscopy credited for drop
Colon cancer incidence rates have dropped 30% in the U.S. in the last 10 years among adults 50 years old and older, primarily because of the widespread uptake of colonoscopy, with the largest decrease in people over the age of 65. Colonoscopy use has almost tripled among adults aged 50 to 75 years, from 19% in 2000 to 55% in 2010.
These new findings come from 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 March 17 by researchers at the American Cancer Society (ACS) as part of a new initiative by the National Colorectal Cancer Roundtable to increase screening rates to 80% by 2018.
Colorectal cancer is the third most common cancer and the third leading cause of cancer death in men and women in the U.S. Its slow growth from a 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. As a result, screening reduces colorectal cancer mortality both by decreasing the incidence of disease and by increasing the likelihood of survival.
Using incidence data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program and from the Centers for Disease Control and Prevention’s National Program of Cancer Registries, researchers found that during the most recent decade of data (2001 to 2010), overall incidence rates of colorectal cancer decreased by an average of 3.4% per year. However, trends varied substantially by age. Rates declined by 3.9% per year among adults aged 50 years 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 has been implicated.
Most strikingly, the rate of decline has surged among those 65 years old and older, with the decline accelerating from 3.6% per year during 2001–2008 to 7.2% per year during 2008–2010. The “larger declines among Medicare-eligible seniors likely reflect higher rates of screening because of universal insurance coverage,” the authors write. “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 rates, mortality rates have also declined rapidly during the past decade. From 2001 to 2010, the 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,” said Richard C. Wender, MD, ACS chief cancer-control officer. “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.”
Source: ACS; March 17, 2014.