We describe a non‐invasive test for detection of prostate cancer based on functional enrichment of prostate adenocarcinoma associated circulating tumor cells (PrAD‐CTCs) from blood samples followed by their identification by immunostaining for pan‐cytokeratins (PanCK), prostate specific membrane antigen (PSMA), alpha methyl‐acyl coenzyme‐A racemase (AMACR), epithelial cell adhesion molecule (EpCAM), and common leucocyte antigen (CD45). This evidence concerns the gene AMACR and Familial prostate cancer.