ORLANDO -- While the incidence of colorectal cancer has been decreasing among individuals older than 50, rates have been rising among those younger than 50, and particularly in white women, a researcher reported here -- suggesting that earlier screening than currently recommended may be advisable for at least some populations.
During the years 2000 to 2014, the incidence rate reported to the Surveillance, Epidemiology and End Results (SEER) database declined among those over 50, with an average annual percentage change of of -3.3% (95% CI -3.5 to -3.1), whereas for those younger than 50, there was an annual percentage increase of 1.4% (95% CI 1.2-1.6, P<0.05), according to Anas Raed, MD, of Augusta University in Augusta, Georgia.
This increase in younger people "is very alarming," he told app.
"Colorectal cancer is the third most common cancer and second leading cause of cancer-related death in men and women in the U.S.," Raed reported in a poster session at the .
This study intended to examine current trends in the incidence of colorectal cancer based on age, sex, race, and location of the primary tumor, with data adjusted to the year 2000 U.S. population. Patients were required to have histologically confirmed primary adenocarcinoma of the colon.
The analysis included 604,033 patients, with 544,430 being older than 50 at the time of diagnosis and 59,603 being younger than 50. Of these, 52.7% were men, 74% were white, 14.6% were black, and 11.4% were of other race/ethnicity.
In the younger age group, the increased incidence was greater among women, with an average annual percentage change of 1.6% (95% CI 1.3-2) compared with men, whose average annual change was 1.1% (95% CI 0.8-1.5, P<0.05).
Also in the younger group, whites had a higher incidence than blacks and others, with an annual percentage change of 1.7% (95% CI 1.4-1.9, P<0.05).
In addition, there was an increased incidence in all segments of the colon, most notably in the right colon, with an annual percentage change of 1.8% (95% CI 1.1-2.4) and the rectum, with an annual percentage change of 1.6% (95% CI 1.1-2.1) compared with a change of 1% (95% CI 0.7-1.4, P<0.05) in the left colon.
Efforts must be made to increase awareness of the need for early screening for colorectal cancer, especially in white women younger than 50, with special attention paid to the right colon and rectum, Raed stated.
"Moreover, because the majority of colon segments need attention, this emphasizes the need for colonoscopy rather than sigmoidoscopy," he said.
Currently, the for asymptomatic, average-risk individuals, although the recommendation also notes that those at higher risk -- because of family history, for example -- may justifiably begin screening earlier.
Primary Source
World Congress of Gastroenterology at ACG2017
Raed A, et al "Is colon cancer incidence increasing in women younger than 50? results of population-based study" ACG@ACG2017; abstract P193.