National CRC Screening Summit | 2025-12 Blood-Based CRC Tests Update

Video Transcription

Video Summary

Dr. Rachel Isaka discussed blood-based screening tests for colorectal cancer (CRC), highlighting studies showing increased screening participation when such tests are offered to individuals who declined traditional stool-based or colonoscopy screenings. These tests detect circulating tumor DNA (ctDNA) in blood samples, using advanced sequencing technology. Three main blood-based tests were reviewed: Epi proColon (mSEPT9), GRAIL’s GARDEN-SHIELD, and Freenome's ctDNA test. Sensitivity for detecting actual CRC ranged from about 68% to 85%, with higher specificity, but sensitivity for precancerous lesions was much lower (12-25%), making these tests better for cancer detection than prevention. Large trials (ECLIPSE, PREEMPT) demonstrated good cancer detection but poor adenoma detection, and challenges remain around follow-up colonoscopy rates and potential disparities. Blood-based tests are not currently cost-effective compared to colonoscopy or FIT and are not endorsed by the U.S. Preventive Services Task Force. Implementation requires careful integration to improve screening without displacing effective existing methods.

Keywords

blood-based screening

colorectal cancer

circulating tumor DNA

Epi proColon

screening participation