After a radical prostatectomy, the risk of biochemical recurrence is highest during the first 2 years but still remains after 10 years.3 4 High preoperative PSA, high Gleason score, high pathological tumour (pT)-stage and positive surgical margins are associated with increased risk of biochemical recurrence.5 In men with biochemical recurrence, high Gleason score and short PSA-doubling time are associated with increased risk of metastases and prostate cancer death while there are conflicting results regarding of pT-stage, surgical margins and time to biochemical recurrence.4 6–11. This evidence concerns the gene KLK3 and prostate carcinoma.