Whole‐genome bisulfite sequencing analysis of circulating tumour DNA for the detection and molecular classification of cancer

Cancer cell-specific variation and circulating tumour DNA (ctDNA) methylation are promising biomarkers for non-invasive cancer detection and molecular classification. Nevertheless, the applications of ctDNA to the early detection and screening of cancer remain highly challenging due to the scarcity of cancer cell-specific ctDNA, the low signal-to-noise ratio of DNA variation, and the lack of non-locus-specific DNA methylation technologies.