Abstract 3690: Monitoring prostate specific membrane antigen or androgen receptor expression on circulating stromal cells in advanced prostate cancer patients and their correlation with patient response

Abstract Background: Metastatic Prostate cancer (mPCa) mortality rates are high despite numerous treatment options against various mechanisms of action, including targeted therapies, i. e. prostate specific membrane antigen (PSMA) -targeted therapy (Pluvicto) or anti-androgen receptor (AR) (Enzulamide, Biculamide). Further, tumor biomarkers (i. e. PSMA and AR) can change over time and with resistance mechanisms that develop after treatments. This suggests that primary biopsies may not represent later PCa tumors necessitating a way to identify patients that may respond to later line therapies. Blood based biopsies can be used to monitor PCa treatment, which can include circulating tumor cells (CTCs) and the newly discovered cancer associated macrophage like cells (CAMLs), a cancer specific circulating phagocytic stromal cells. Interestingly, while PSMA Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 3690.