Blood-Based CRC Screening Enters Clinical Practice—but Advanced Adenoma Detection Remains the Weak Link: FDA | July 2026

Introduction:

Blood-based colorectal cancer (CRC) screening has entered clinical practice with FDA approval of SimpleScreen CRC, a plasma cell-free DNA test for average-risk adults aged ≥45 years. The test offers a convenient alternative for patients unwilling to undergo colonoscopy or stool-based screening, but its ability to detect precancerous lesions remains limited.

Why is this important?

Screening uptake remains inadequate, partly because patients avoid colonoscopy or stool testing.

A simple blood test could improve participation among previously unscreened adults.

However, an effective CRC screening strategy should ideally prevent cancer by detecting advanced precancerous lesions, not merely detect established cancer.

Clinicians need to understand where blood-based screening fits relative to established options.

Key Takeaways:

SimpleScreen CRC is approved for screening average-risk adults aged ≥45 years.

A positive blood test must be followed by diagnostic colonoscopy.

CRC sensitivity was 81.1% in the US-population-adjusted PREEMPT CRC analysis.

Specificity for advanced colorectal neoplasia was 90.4%.

The major limitation was detection of advanced precancerous lesions: sensitivity only 13.7%.

Blood-based screening may be particularly useful for patients who repeatedly decline colonoscopy or stool-based testing.

It should not replace diagnostic colonoscopy in symptomatic patients.

It is also not a substitute for surveillance colonoscopy in high-risk individuals.

Patients should understand the distinction between detecting cancer and preventing cancer through removal of advanced adenomas.

What’s New?

CRC screening now includes an FDA-approved blood-based option, potentially lowering barriers to participation. However, its low sensitivity for advanced precancerous lesions means it should not be considered biologically equivalent to colonoscopy.

Bottom Line:

Blood-based CRC screening may improve screening uptake, especially among patients declining established tests. Its major limitation is poor advanced adenoma detection—making it better at finding cancer than preventing it.