GPC1 and posterior cortical atrophy: All 15 out of 15 patients with localized PCa (100%) had CTCs (CK+, PSMA+, and GPC-1+ cells) in their SF, varying from approximately 66.9 to 306.7 cells per mL and from 63 to 613 units per sample, representing a 20–30-fold improvement in CTC isolation when compared with previously reported studies where CTCs were isolated from blood or urine [32,38].