The International Society of Urological Pathology grade group at surgical margin (SM) ≥ 5 (hazard ratio [HR] 3.37, 95% confidence interval [CI] 1.48–7.68), and max length of cancer at SM ≥ 4 mm (HR 2.59, 95% CI 1.27–5.32), and nadir PSA ≥ 0.03 (HR 8.66, 95% CI 4.66–16.1) were identified as factors predicting biochemical failure. This evidence concerns the gene KLK3 and cancer.