Rinnab et al., in a single-centre retrospective study, analyzed 50 men with biochemical relapse after RP for PCa (average PSA serum value: 3.62 ng/mL; range 0.5–13.1 ng/mL); the authors considered the Se and Spe of 11C-Ch PET-CT only in patients with PSA serum level lower than 2.5 ng/mL, reporting 91% and 50%, respectively [34]. This evidence concerns the gene KLK3 and posterior cortical atrophy.