What to look for in cell-free DNA from breast cancer patients
In a recent paper by Cheng J et al., published in Breast Cancer Research and Treatment, the authors resume the debate about the usefulness of liquid biopsy in breast cancer (BC) patients. They found an independent prognostic role of cell-free DNA (cfDNA) integrity in repetitive DNA elements (ALU and LINE1) detected by quantitative PCR in metastatic BC patients. They also observed a reduction in cfDNA concentration and an increase in cfDNA integrity from baseline to the first cycle of systemic therapy . This analysis was based on the hypothesis that, as malignant cells undergo necrosis and processes other than apoptosis, circulating tumor DNA is consequently expected to be composed of longer fragments.
This perspective has fueled the hope of identifying a new biomarker that is easy to determine and analyze. As the authors point out, there are many factors influencing the quality and quantity of cfDNA. However, it is clear that the preanalytical hurdles must be crossed, if cfDNA is to...