Serum DKK-1 significantly decreased from baseline to 6 months in chronic ADT users (− 10.06%, p = 0.0057), former ADT users (− 12.77%, p = 0.0239), and PCa controls (− 16.73, p = 0.0022), but not in acute ADT users (12.91%, p = 0.11) (Fig. 1b). Here, DKK1 is linked to posterior cortical atrophy.