Liquid biopsy for cancer screening, diagnosis, and treatment.

The goal of precision medicine in an oncology context is to offer individuals and their families the most effective and efficient methods available to screen, diagnose, and plan treatment. Much like the rapidly expanding use of circulating free DNA testing to screen for chromosomal anomalies during pregnancy, circulating tumor DNA (ctDNA) can assess for degraded DNA fragments released into the blood by tumors. Also known as liquid biopsy (LB), this technology has the potential to improve cancer screening and postdiagnosis monitoring, but it can also provide genetic information about evolving tumor characteristics, allowing clinicians to pinpoint the most appropriate treatment options and monitor response in real time. Novel uses for ctDNA are emerging almost daily, and every provider should know at least that earlier diagnosis and more targeted therapy may now be possible for many different cancers because of LB. Patients expect their providers, including nurse practitioners, to have an understanding of genomics and when advances in genomics might directly benefit them. Liquid biopsy techniques have been rapidly adopted by the oncology community, with findings moving quickly into clinical care.