OBJECTIVE: To determine the role of transrectal ultrasound, especially in association with color Doppler, in the diagnosis of prostate cancer. MATERIALS AND METHODS: Eighty-four cases of patients who underwent transrectal biopsy were prospectively analyzed. In all patients, besides the traditional gray-scale sonogram, color Doppler study was performed in search of hypervascular foci. The results were compared with the histopathologic diagnosis. RESULTS: The gray-scale sonogram showed a 67.7% sensitivity, 52.8% specificity, positive predictive value of 45.6% and negative predictive value of 73.6%. The association with color Doppler increased the specificity (from 52.8% to 79.2%) and the positive predictive value (from 45.6% to 62.0%) although it has caused a decrease in the sensitivity (from 67.7% to 58.0%). Besides, the study had 32.2% of missed cancers by both methods, and these patients, although having less extensive cancers all of them were clinically significant (Gleason 6 or more). CONCLUSION: Transrectal ultrasound findings, even in association with color Doppler, are not sufficiently accurate to determine whether a patient should or not be submitted to biopsy.

Keywords: Prostate, Prostatic cancer, Transrectal ultrasound, Color Doppler, Prostate biopsy