Prostate cancer is best diagnosed by?

3D Trans-Urethral Ultrasound (TUUS) is a new technique for the diagnosis and treatment of prostate disease. TUUS provides real-time, high resolution images of the prostate. Because of the central location of urethra, the TUUS devices can use higher frequency than transreactal ultrasound (TRUS), since there is less tissue to traverse to the prostate borders. TUUS can be used as a therapy guidance tool during and after transperineal interstitial permanent prostate brachytherapy. PSA (prostatic specific antigens) are a good tool for screening the prostatic cancers, but definitive diagnosis is obtained by biopsy. They are neither sensitive nor specific.