Colorectal cancer is among the leading causes of cancer-related death globally and is highly preventable when detected early through routine screening. Current screening guidelines recommend that average-risk adults aged 45 years and older undergo regular colorectal cancer screening. Despite these recommendations, an estimated 60 million eligible individuals in the United States do not participate in screening, leaving a substantial screening gap that contributes to preventable morbidity and mortality.
Although colonoscopy is widely regarded as the screening gold standard and stool-based tests are increasingly popular because they can be completed at home, adherence is limited by multiple patient-level barriers. These include the need for bowel preparation, anticipated or experienced discomfort, embarrassment, inconvenience, time off work, limited healthcare access, costs, lack of awareness of guidelines, and fear of results. Cultural stigma and a tendency to postpone preventive care when asymptomatic further reduce uptake.
Recognizing that no single screening approach appeals to everyone, developers have advanced blood-based colorectal cancer screening tests as an alternative option. The U.S. Food and Drug Administration approved the Shield blood-based test in 2024. In July 2026, the FDA approved Freenome’s SimpleScreen colorectal cancer blood test, marking a second FDA-cleared blood-based screening option intended for average-risk adults.
The FDA clearance for SimpleScreen is supported by the large PREEMPT CRC clinical study, which enrolled more than 48,000 participants. In that study, the SimpleScreen blood test correctly identified roughly 8 out of 10 colorectal cancers. It also produced negative results for about 9 out of 10 individuals without colorectal cancer or advanced precancerous lesions. These figures reflect the test’s operating characteristics as reported in the clinical evidence underlying approval.
SimpleScreen is a blood-based assay that detects molecular signals associated with colorectal neoplasia. Specifically, the test evaluates patterns of cytosine-phosphate-guanine (CpG) methylation—DNA methylation changes that commonly occur early in cancer development and can serve as biomarkers for screening. After a standard venous blood draw, samples are analyzed in a laboratory for these methylation signatures that may indicate the presence of cancer or precancerous cells.
The SimpleScreen workflow begins with a clinician-ordered blood draw. Samples are sent to a central laboratory for molecular analysis and results are typically made available to the ordering provider within approximately two weeks. Clinicians review results with patients and advise on next steps. Importantly, a positive SimpleScreen result is considered a screening signal that requires a diagnostic follow-up colonoscopy to confirm or rule out colorectal cancer or advanced precancerous lesions.
Experts emphasize that colorectal cancer screening is not one-size-fits-all. The American Cancer Society guideline identifies stool-based tests (including molecular stool assays) and visual examinations such as colonoscopy as preferred screening options. Earlier research showed many patients preferred stool-based tests to colonoscopy; more recent data suggest that a significant portion of people would prefer a blood-based screening option when available.
Paul Limburg, MD, MPH, Chief Screening Medical Officer at Abbott Cancer Diagnostics, discussed with Medical News Today that patient preference, access, and clinician recommendation should guide test selection. Framing screening as a routine, manageable preventive measure and highlighting that the best test is the one a patient will complete are practical strategies to improve participation.
The FDA approval of SimpleScreen adds another evidence-based screening option that may be less intimidating or more convenient for some patients compared with colonoscopy or stool-based tests. Because convenience and acceptability are key drivers of screening behavior, offering blood-based tests could encourage previously unscreened or overdue individuals to engage in screening, potentially increasing early detection when treatment is most effective. However, blood-based screening is presented as a complementary option; confirmatory colonoscopy remains necessary for positive results and colonoscopy continues to serve as the diagnostic standard.
Note: All data and statements in this summary are drawn from the referenced Medical News Today article reporting on FDA approval and related clinical evidence; additional operational or guideline details beyond those reported in the source were not provided.