Howard Scher, MD, FASCO, Memorial Sloan-Kettering Cancer Center, New York, NY, discusses the development and validation of prognostic biomarkers for the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC), highlighting how these can be used to guide treatment. Dr Scher gives an overview of existing biomarkers in prostate cancer, including AR-V7, and outlines results from the PROPHECY (NCT02269982) trial. Dr Scher also talks on the Epic Sciences platform and research investigating molecular profiling and genomic instability in prostate cancer. This interview took place during the 2021 Genitourinary Cancers Symposium.