KLK3 and metabolic syndrome: Moreover, emerging evidence indicates that MetS and its components were associated with an increased risk of PCa biochemical recurrence (BCR) (8, 9), which was defined as being present in the event of two consecutive increasing postoperative serum prostate-specific antigen (PSA) values ≥0.2 ng/ml among prostate cancer patients who underwent radical prostatectomy (RP).