Liquid biopsies offer more nuanced profile

Dear Doctors: My mother has been diagnosed with breast cancer, and I’m helping with her medical appointments. Her oncologist says she needs a liquid biopsy. She has already had a biopsy – that’s how they found the cancer. Why would she need another one?

Dear Reader: A biopsy is a diagnostic medical procedure to collect cells from the body, then examine them under a microscope for abnormalities. Thi…