Cancers are easier to treat if they’re detected at relatively early stages of their development. Liquid biopsies, which detect molecular markers of cancer in easily accessible body fluids, hold promise as routinely deployable tools for that purpose. But how early can such tests in fact detect malignancy? To answer that question, researchers led by Ludwig Johns Hopkins’ Yuxuan Wang, Nickolas Papadopoulos and Co-director Bert Vogelstein with a Johns Hopkins colleague collected serial plasma samples from the Atherosclerosis Risk in Communities (ARIC) study, including 26 participants diagnosed with cancer and 26 matched controls. Eight of these participants scored positive with a multicancer early detection (MCED) test at a selected “index” time point and were diagnosed with cancer within 4 months of that blood draw. The researchers reported in a May issue of Cancer Discovery that in six of those eight participants, they were able to analyze plasma samples collected 3.1 to 3.5 years prior to diagnosis. In four, the same mutations detected by the MCED test were identified, but at about 8 to 80-fold lower levels relative to the levels at 4 months before diagnosis. The findings suggest circulating tumor DNA can be detected more than three years before cancer diagnosis and indicate how sensitive a liquid biopsy needs to be for that to happen.
Detection of cancers three years prior to diagnosis using plasma cell-free DNA
Cancer Discovery, 2025 May 22