OBJECTIVE: To investigate the manner to increase specificity in the decision-making process for the performance of prostate biopsy.METHODS: We include in this study men with PSA between 4 and 10 ng/ml and free/total PSA < 20%, candidates for prostate biopsy. Patients receiving 5 alpha reductase inhibitors or with previous biopsies were excluded. Analyzed variables: total PSA, total testosterone, free and bioavailable testosterone, FSH, LH, SHBG, 17 hydroxyprogesterone, Androstenedione, prostatic volume measured by transrectal ultrasound, total testosterone/PSA, testosterone/free PSA, bio available testosterone/PSA and PSA density, total testosterone/prostate volume, free testosterone/prostate volume and bioavailable testosterone/prostate volume. RESULTS: A total 109 patients have been included, divided into 2 groups according to the results of the biopsy. Significant differences were observed in prostatic volume (Group 1: 36.6cc and Group 2: 52.8 cc; p=0.04), PSA density (Group 1: 0.24 Group 2: 0.17; p=0.002), total testosterone/prostate volume (Group 1: 0.15 and Group 2: 0.10; p=0.02) free testosterone/prostate volume (Group 1: 0.002 Group 2: 0.001; p=0.01) and bioavailable testosterone/prostate volume (Group 1: 0.06 Group 2: 0.04; p=0.007). CONCLUSION: The decision for a prostate biopsy on patients with a PSA between 4-10 ng/ml with free/total ratio <20% continues to be an issue, however, we can optimize decision using other parameters such as prostate volume, PSA density and bioavailable testosterone/prostate volume.