Transrectal ultrasound for staging prior to radical prostatectomy.

Transrectal ultrasound (TRUS) was used to predict tumor stage in 43 patients prior to radical prostatectomy. For assessing extracapsular extension, the sensitivity was 54 percent, specificity 58 percent, and accuracy 56 percent. For detecting seminal vesicle involvement, the sensitivity was 60 percent, specificity 89 percent, and accuracy 82 percent. The predominant tumor echo pattern was isoechoic in 37 percent of cases, mixed (hyper-, iso-, and hypoechoic) in 47 percent, and hypoechoic in 16 percent. An anterior-posterior to transverse dimension ratio of greater than 0.8 suggested diffuse involvement of the prostate with an increased chance of extracapsular spread.