The colorectal cancer screening shift: 5 study notes

Stool DNA testing climbed sharply after the pandemic began while colonoscopy and fecal immunochemical test use fell, a study of nearly 25 million privately insured Blue Cross Blue Shield beneficiaries found. 

The study was published Oct. 21 in JAMA Network Open and was led by researchers from New Haven, Conn.-based Yale University and the University of California Los Angeles. They  analyzed 24,973,642 commercially insured beneficiaries ages 50-75 from 2017 to 2024. About half were women, and nearly one-third received at least one colorectal cancer screening test during the study period.

Here are five things to know:

1. Most beneficiaries were ages 50-64, with a smaller share ages 65-75. Regionally, the cohort was concentrated in the South (41.78%), followed by the Midwest (21.69%), Northeast (16.89%) and West (16.56%).

2. Screening patterns shifted after COVID-19’s onset, with both colonoscopy and stool-based FIT declining. The mean bimonthly colonoscopy rate fell from 1.29% in the pre-pandemic period, from January 2017 to February 2020, to 1.14% after screening resumed, from July 2020 to December 2024. The mean bimonthly FIT rate decreased from 0.54% to 0.38% over the same periods.

3. Stool DNA test use rose from 0.19% pre-pandemic to 0.61% post-pandemic and moved from the fourth-most common screening option to the second-most common, behind colonoscopy. Fecal occult blood test use declined from 0.26% to 0.11%. Other modalities remained rare. CT colonography, flexible sigmoidoscopy and double-contrast barium enema collectively accounted for less than 1% of screening tests in both periods.

4. Men underwent colonoscopy more often than women, while women were more likely to use stool-based tests, including stool DNA testing and FIT.

5. People living in the top 20% of area-level socioeconomic status ZIP codes had higher colonoscopy and higher stool DNA testing use than those in the bottom 20%, but lower FIT use. Metropolitan residents were more likely than nonmetropolitan residents to undergo colonoscopy and FIT, while stool DNA testing was similar across metropolitan and nonmetropolitan areas.