cfDNA methylation patterns can signal breast cancer risk years before diagnosis

A longitudinal study published in Cell Genomics has found that genome-wide cell-free DNA (cfDNA) methylation patterns in blood plasma can indicate future breast cancer risk up to nine years before clinical diagnosis.

Researchers utilized biospecimens from the Ontario Health Study, a prospective cohort of more than 40,000 participants. By linking this data with the Canadian Cancer Registry, investigators analyzed 491 plasma samples from individuals who were cancer-free at the time of collection but later developed breast or prostate cancer. The study identified that hypermethylated enhancer regions provided the strongest predictive signals for breast malignancies.

The findings suggest that these pre-diagnosis methylation profiles reflect a combination of emerging tumor cells and systemic host-immune changes. Experts emphasize that this method is best suited as a complementary risk-stratification tool rather than a standalone replacement for traditional diagnostic methods like mammography.