The optimal diagnostic threshold using Youden index was 14.25 mm for MRI-based tumor size (Youden index = 0.520, sensitivity = 78.9% and specificity = 73.1%); 13.84 for SUVmax (Youden index = 0.449, sensitivity = 52.6% and specificity = 92.3%); 7.195 for SUVmean (Youden index = 0.425, sensitivity = 57.9% and specificity = 84.6%); 1.395 cm3 for PSMA-TV (Youden index = 0.601, sensitivity = 94.7% and specificity = 65.4%); and 0.8717 for logPSA (Youden index = 0.30, sensitivity = 68.4% and specificity = 61.5%). The gene discussed is FOLH1; the disease is neoplasm.