Incidence of colon cancer in the US is decreasing with increased use of colonoscopy

By Kate Bass, B.Sc.Mar 17 2014

Colorectal cancer, commonly called colon cancer, is the third most common cancer and the third leading cause of cancer death in the United States. Research, published today, by the American Cancer Society shows that the incidence of colorectal cancer among adults aged 50 years or more has fallen by 30% in the US over the last 10 years. This is thought to be primarily due to the widespread uptake of colonoscopy screening, which has almost tripled among adults aged 50 to 75 years (19% in 2000; 55% in 2010).

Colon screening allows detection and removal of precancerous polyps before invasive colorectal cancer develops, providing a rare opportunity to prevent cancer. It can also detect early cancer, against which treatment is more successful. A new initiative by the National Colorectal Cancer Roundtable aims to increase colon screening rates to 80% by 2018 and improve awareness of the potential for early detection and prevention of colon cancer.

The latest research, led by Rebecca Siegel, used incidence data provided by the North American Association of Central Cancer Registries (NAACCR). It showed that incidence rates for colorectal cancer decreased on average by 3.4% per year, but that the trend varied substantially by age. Most striking was the accelerated rate of decline among those aged 65 years and older. In this population, the incidence of colon cancer fell by 3.6% per year during 2001-2008 and by 7.2% per year during 2008-2010. The authors conclude that “larger declines among Medicare-eligible seniors likely reflect higher rates of screening because of universal insurance coverage”.

The reduction in colorectal cancer incidence is mirrored in mortality rates, which have also declined most rapidly within the past decade. From 2001 to 2010, rates decreased by approximately 3% per year, compared with declines of approximately 2% per year during the 1990s.

Richard C Wender MD, American Cancer Society chief cancer control officer commented “These continuing drops in incidence and mortality show the lifesaving potential of colon cancer screening...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”.