Noninvasive cancer biomarkers in solid malignancies: circulating tumor DNA—clinical utility, current limitations and future perspectives

Since the first publication of human genome, the cancer community witnessed a substantial progress in available technologies to genetically characterize tumor samples (1). Turnaround times and costs are rapidly decreasing, along with the availability of a myriad of tests using a variety of samples other than conventional biopsy tumor tissue. Detection of circulating tumor DNA (ctDNA) in cancer patients has the potential to offer a precise and non-invasive tumor evaluation. Ranging from cancer diagnosis to prognostic stratification, and treatment guidance, applicability of ctDNA may allow its broad incorporation into clinical practice (2-4).