Systematic transrectal ultrasound guided prostate biopsy after negative digitally directed prostate biopsy.

The diagnostic accuracy of digitally directed prostate biopsies was evaluated by performing systematic ultrasound guided biopsies on 44 patients who had previously had a negative prostate biopsy by systematic digitally directed technique. All 44 patients still had palpable abnormalities. Core biopsies (2 to 4) were obtained from each lateral lobe of the prostate with 2 additional cores directed at hypoechoic lesions. Only 4 of the 44 ultrasound directed biopsies (9.1%) were positive for cancer. These results confirm the postulate that random systematic digitally directed biopsy is highly accurate in making the diagnosis of prostate cancer. They also suggest that performing biopsies in a systematic pattern is more important than the method used to guide the biopsy needle.