Umberto Malapelle, PhD, University of Naples Federico II, Naples, Italy, discusses how investigating cell free DNA (cfDNA) release in solid tumours via liquid biopsy can be a useful diagnostic tool. The quantity and quality of mutated DNA in the bloodstream can provide crucial insight into the type of tumor that the patient has, which could then help clinicians to make better treatment recommendations for patients. This interview took place at the International Society of Liquid Biopsy (ISLB) 2021 Virtual Meeting.