Transrectal ultrasonography of the prostate.

Transrectal prostatic ultrasonography has been performed in 203 patients within the last year. This new diagnostic modality has proven reliable in quantitating decrease in volume of the primary tumor following therapy in 71% of patients with prostatic carcinoma (10 of 14 patients) in whom long-term follow-up is available. In 12 patients staged prior to radical prostatectomy, prostatic ultrasonography was extremely valuable in detecting capsular involvement. This new diagnostic modality has significantly enhanced the staging capabilities in patients with localized prostatic carcinoma.