Circulating tumor DNA: A potential biomarker from solid tumors' monitor to anticancer therapies

Circulating tumor DNA (ctDNA) in the peripheral blood is a liquid biopsy that contains representative tumor information including gene mutations. ctDNA is a promising new avenue for real-time monitoring of tumor progression. As a noninvasive biomarker and potential surrogate for the entire tumor genome, it has been applied to the detection of driver gene mutations and epigenetic alteration as well as monitoring of tumor burden, acquired resistance, tumor heterogeneity, and early diagnosis. Since precise therapy is a strategy that optimal therapy is decided based on simultaneous tumor genome information, ctDNA may help perform dynamic genetic surveillance. Dynamic marker surveillance may provide critical information to identify disease progression and guide therapeutic options. This review provides an overview on related articles about ctDNA, with a focus on monitoring response of solid tumors to anticancer therapies.