[Sonographic diagnosis of prostatic cancer].

In 75-80% of all clinically significant prostate cancer, the peripheral zone appears to be hypoechoic on transrectal ultrasound (TRUS). However, examination by TRUS alone in a screening program is not recommended due to its low sensitivity. The combination of prostate-specific antigen, digital rectal examination, and TRUS increases the detection rate of prostate cancer. In prostate cancer arising from the transition zone, TRUS findings are often nonspecific. Even prostate biopsies might be negative due to the location of this tumor. Anterior biopsies of the transition zone will identify these prostate cancers. Color Doppler ultrasound of the prostate has little additional value over TRUS alone in the diagnosis of prostate cancer.