Home Hematology and Oncology ASCO: ‘Liquid Biopsy’ Shows Promise for Tumor Surveillance

ASCO: ‘Liquid Biopsy’ Shows Promise for Tumor Surveillance

Guardant360 predicts cancer DNA mutations and could help tailor treatments to avoid drug resistance

MONDAY, June 6, 2016 (HealthDay News) — A new blood-based “liquid biopsy” could be a groundbreaking alternative to the traditional biopsy, according to findings presented at the annual meeting of the American Society of Clinical Oncology, held from June 3 to 7 in Chicago.

Philip Mack, Ph.D., director of molecular pharmacology at the University of California, Davis, Comprehensive Cancer Center, and colleagues used a new genetic scan called Guardant360 that analyzes cancer DNA in patients’ blood, looking for mutations in 70 different cancer-related genes. In the study, the most common types of cancer were advanced lung cancer (37 percent), breast cancer (14 percent), and colorectal cancer (10 percent).

The researchers compared the liquid biopsy results to genetic tests performed on biopsied cancer tissue for 398 of the patients, and found that blood samples contained the same mutations as tissue 94 to 100 percent of the time, Mack said. The investigators also found that the test could detect genetic changes in a cancer which occur as tumors gain resistance to targeted cancer drugs. Overall, the liquid biopsy revealed possible treatment options for 63.6 percent of patients tested, including U.S. Food and Drug Administration-approved drugs as well as eligibility for clinical trials.

“At this point, we cannot dispense with that initial tumor biopsy,” Mack told HealthDay. He believes the real value of liquid biopsy will show itself as a patient’s cancer treatment proceeds. Most patients never undergo a second tissue biopsy during treatment to check their progress, “unless there’s a compelling therapeutic option available,” he said. Liquid biopsy provides an easier way to keep track of treatment. “You can get a blood draw basically at any time, so you can really monitor the progression of a patient’s tumor over time,” Mack said.

The study received funding from Guardant Health, which produces the test used in the study.

Press Release
More Information

Copyright © 2016 HealthDay. All rights reserved.