Dr. Bardia on the Clinical Utility of Liquid Biopsies in Breast Cancer

Aditya Bardia, MD, MPH, director of Precision Medicine at the Center for Breast Cancer and founding director of the Molecular and Precision Medicine Metastatic Breast Cancer Clinic, Massachusetts General Hospital Cancer Center, and assistant professor of medicine, Harvard Medical School, discusses the clinical utility of liquid biopsies in breast cancer.

Tumor genotyping has become more widespread across oncology, says Bardia. In breast cancer, tumor genotyping can be challenging in patients with bone metastases, particularly with regard to serial tissue testing. Liquid biopsies, which assess circulating tumor DNA (ctDNA), have emerged as a less invasive alternative to tissue biopsies, explains Bardia.

As with tissue biopsies, liquid biopsies can identify potentially actionable alterations. An example of an actionable alteration is PI3KCA, which is a common mutation detected in patients with hormone receptor—positive breast cancer. In the phase III SOLAR-1 trial, patients with PI3KCA-mutant breast cancer derived more benefit from the PI3K inhibitor alpelisib (Piqray) plus fulvestrant versus fulvestrant alone, irrespective of the type of biopsy that was performed.