Circulating tumor DNA for triple-negative breast cancer diagnosis and treatment decisions.

Triple-negative breast cancer (TNBC) is a highly aggressive disease characterized by a high number of relapses and poor overall survival. The heterogeneity of the disease and the limited treatment options compared to other breast cancer subtypes mainly explain these clinical outcomes. New biomarkers are urgently needed to improve the management of TNBC. Circulating tumor DNA, identified by tumor-related molecular alterations, could be used in the context of non-invasive "liquid biopsy" and help in TNBC diagnosis and treatment decisions. In this review, we discuss the key issues related to the potential of circulating tumor DNA to improve the management of this disease and the future steps to overcome before its implementation into clinical routine within the next 5 years.