HMN 2025: How Less than half complete follow-up colonoscopy after abnormal blood-based cancer test

Just under half of patients receiving an abnormal blood-based colorectal cancer screening test result receive a follow-up colonoscopy (FU-CY) within six months, according to a study published online July 29 in Gastroenterology.

Timothy A. Zaki, M.D., from the University of California, Los Angeles (UCLA), and colleagues analyzed closed claims data to determine the FU-CY rate after an abnormal blood-based test result and identified predictors of FU-CY using national data. The analysis included 6,068 individuals who underwent a commercially available, blood-based colorectal cancer screening test (Shield, Guardant Health) with linked administrative data.

The researchers found that 7.4% of individuals had an abnormal result. Of the 228 individuals with at least six months of follow-up, 49% received an FU-CY within six months (mean time to FU-CY, 66.4 days). At any time, 128 individuals (56%) received an FU-CY (mean time to FU-CY, 98.3 days overall). Individuals with Medicare Advantage (adjusted odds ratio [aOR], 0.26) were less likely to undergo FU-CY within six months versus those with private insurance. FU-CY at six months was also associated with having fewer comorbidities (aOR, 0.90). Age, race/ethnicity, and U.S. census region were not significant predictors of FU-CY within six months.

“Blood-based colorectal cancer screening is promising, but it only works if individuals complete the follow-up colonoscopy,” senior author Folasade May, M.D., Ph.D., also from UCLA, said in a statement. “More efforts are needed to help patients follow through to actually diagnose and treat the disease.”

Several authors disclosed ties to relevant organizations.

2025 .