Colon Cancer Deaths Decline
The incidence of colon cancer in older adults decreased by 30% in the last decade, coinciding with a tripling of the colonoscopy rate, the American Cancer Society (ACS) reported.
Overall, the incidence of the third most common cancer decreased by 3.4% annually from 2001 to 2010. However, the benefit was driven by a 3.9% annualized decline in people ≥50, which was offset to some extent by a 1.1% annual increase in younger people. Colon cancer mortality decreased by a similar rate during the same time frame, reported Rebecca Siegel, MPH, and colleagues, all from the ACS in Atlanta.
Much of the credit for the lower incidence of colorectal cancer goes to improved uptake of colonoscopy among people ages 50 to 75, which rose from 19% in 2000 to 55% in 2010, they wrote in the March/April issue ofCA: A Cancer Journal for Clinicians.
“Among adults aged 50 years and older, the rate of decline has surged, particularly among those aged 65 years and older, among whom the annual percent decline in distal tumors accelerated from 5.2% during 2001 to 2008 to 9.5% during 2008 to 2010,” they said.
“Larger declines among Medicare-eligible seniors likely reflect higher rates of screeningbecause of universal insurance coverage,” they added. “In 2010, 55% of adults aged 50 to 64 years reported having undergone a recent colorectal cancer screening test, compared with 64% of those age 65 years and older.”
The findings came from an analysis of data from the National Cancer Institute Surveillance, Epidemiology, and End Results (SEER) program, the North American Association of Central Cancer Registries, and the National Center for Health Statistics.
Collectively, the data documented declines in colon cancer incidence and mortality over the past decade, but also showed that not all segments of the population benefited equally.
From 2006 to 2010, colon cancer incidence was highest in non-Hispanic blacks: 63.8 cases per 100,000 in men and 47.8 per 100,000 in women. Asian/Pacific Islanders had the lowest rates (40.8/100,000 in men, 31/100,000 in women). Overall incidence during the 5-year period were 51.7/100,000 in men and 39.1/100,000 in women.
Similar disparities emerged from the analysis of mortality, which ranged from 29.4/100,000 in black men and 19.4/100,000 in black women to 13.1 and 9.7/100,000 in Asian/Pacific Islander men and women, respectively.
The data also showed considerable variation in tumor location by age. The proportion of proximally located tumors increased from 27% in men <50 to 49% in people ≥80. A similar age-related pattern was seen in women. Distally located tumors were most common in men 50 to 64 (27%) and women <50 (28%) and least common in men and women >80 (20% and 17%, respectively).
Tumors arose most often in the rectum among men and women <50 (41% and 37%, respectively) and least often in men and women >80 (22% and 17%, respectively).
Despite the improving epidemiologic picture, colorectal cancer will remain the third most common and third most deadly cancer in the U.S.. During 2014, about 137,000 new cases of colorectal cancer will be diagnosed (71,830 in men, 65,000 in women) and 50,000 people will die of the disease (26,270 men, 24,040 women).
“These continuing drops in incidence and mortality show the lifesaving potential of colon cancer screening, a potential than an estimated 23 million Americans between ages 50 and 75 are not benefiting from because they are not up to date on screening,” Richard Wender, MD, ACS chief cancer control officer, said in a statement.
“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,” he stated.
Source reference: Siegel RH, et al. “Colorectal Cancer Statistics, 2014” CA Cancer J Clin 2014; DOI: 10.3322/caac.21220.