Unfortunately, ADT is not curative and most patients will relapse within 2 years despite castrate levels of serum testosterone (50 ng/dL); where disease recurrence is defined as raising PSA levels on 2 subsequent occasions with possible evidence of tumor progression via imaging analysis (bone scan, computated tomography (CT), or magnetic resonance imaging (MRI)) or repeat biopsies [2, 3, 17–19]. Here, KLK3 is linked to neoplasm.