KLK3 and cancer: ROC-CA showed that the nadir PSA, compared with other predictors, had the highest area under the curve (AUC) for predicting residual PCa and residual cancer nests with GS ≥7 in the remaining prostate (AUC: 0.787 and 0.816, respectively, both p < 0.001; Figures 3A, B, and Table 2).