Is this the video you are referring to @windyshores ?

Biomarkers for Treatment and Progression | 2021-2022 EMBRACE MBC Virtual Forum Series
"Caroline Block, MD, presents practical information on how Dana-Farber oncologists follow patients’ disease progression and work with patients living with metastatic breast cancer to make treatment decisions. Dr. Block covers topics such as scans, blood tests and tumor markers: when, why, and how they are used and the frequencies for each. The discussion includes areas of research including circulating tumor DNA based assays."