The potential of circulating tumor cells as a liquid biopsy to guide therapy in prostate cancer.

Miyamoto and colleagues present data that prostate-specific antigen/prostate-specific membrane antigen (PSA/PSMA)-based measurements of androgen receptor (AR) signaling in circulating tumor cells (CTC) enable real-time quantitative monitoring of intratumoral AR signaling. This finding indicates that measuring AR signaling within CTCs may help to guide therapy in metastatic prostate cancer and highlights the use of CTCs as liquid biopsy.