A large-scale genomic analysis finds that patterns of genetic changes detected in blood samples (liquid biopsy) closely mirror those identified in traditional tumor biopsy. With blood samples from more than 15,000 patients and 50 different tumor types, this is one of the largest cancer genomics studies ever conducted. The study was featured in a press briefing on June 4, 2016 and presented at the 2016 American Society of Clinical Oncology (ASCO) Annual Meeting (June 3-7) in Chicago, Illinois. “These findings suggest that analysis of shed tumor DNA in patient blood, also known as a liquid biopsy, can be a highly informative, minimally-invasive alternative when a tissue biopsy is insufficient for genotyping or cannot be obtained safely,” said study presenter Philip Mack, Ph.D., Professor and Director of Molecular Pharmacology at the University of California Davis Comprehensive Cancer Center. “Moreover, this test, known as Guardant360, provides an unparalleled opportunity to monitor changes in the cancer as it evolves over time, which can be critical when patients and physicians are discussing treatment options for continued tumor control.” Currently, doctors largely rely on tumor biopsies to assess whether tumors have certain genetic mutations that can be targeted by available cancer drugs. Tumor biopsy involves a surgical procedure, however, and patients are not always healthy enough to undergo it, and frequent repeated tests are not always feasible.Tumor cells also sh ed small pieces of their genetic material or DNA into the bloodstream. This so-called circulating tumor DNA (ctDNA) can be collected from the blood and analyzed in the lab to help inform treatment decisions for individual patients, similar to tumor biopsy.Login Or Register To Read Full Story