Abstract
Prenatal cell-free DNA (cfDNA) sequencing is a screening method that utilizes circulating cfDNA in maternal blood to identify fetal chromosomal abnormalities. Beyond its primary application in prenatal care, cfDNA sequencing can detect occult maternal malignancies before they manifest clinically, presenting a critical window for early therapeutic intervention. Here we report a single case in detail from the Incidental DEtection of maternal Neoplasia Through non-Invasive cell-Free DNA analysis (IDENTIFY) study, in which an abnormal cfDNA sequencing result from an asymptomatic pregnant woman identified locally advanced cholangiocarcinoma. Her disease was successfully treated with a multi-modal approach, and she achieved an ongoing complete response.