From January 1978 to June 1990, 120 prostate cancer patients were submitted to radical retropubic prostatectomy. Local pathological staging evidenced 70 patients (58%) in stage B of disease (intraprostatic disease) and 50 patients (42%) in stage C of disease (extraprostatic disease). Sensitivity of rectal examination, transrectal ultrasonography, CT or NMR for stage B was 61%, 75%, 54% respectively and for stage C 61%, 70%, 50%. This study underscores the effectiveness of transrectal ultrasonography in the diagnosis of prostate cancer non evidenced at rectal examination. CT and NMR are not valuable for local staging and are now used only in patients at risk for extraprostatic or systemic disease.