Comparison Of Contrast Enhanced Color Doppler Targeted Biopsy With Conventional Systematic Biopsy: Impact On Prostate Cancer Detection

Abstract

We performed a prospective study to determine whether a limited biopsy approach with contrast enhanced color Doppler ultrasound targeted biopsy of the prostate would detect cancer as well as gray scale US guided systematic biopsy with a larger number of biopsy cores. We examined 230 male screening volunteers with a total prostate specific antigen of 1.25 ng./ml. or greater and free-to-total prostate specific antigen less than 18%. Two independent examiners evaluated each subject and a single investigator performed 5 or fewer contrast enhanced targeted biopsies into hypervascular regions in the peripheral zone during intravenous infusion of the US contrast agent Levovist (Schering, Berlin, Germany). Subsequently another examiner performed 10 systematic prostate biopsies. The cancer detection rates of the 2 techniques were compared. Cancer was detected in 69 of the 230 patients (30%), including 56 (24.4%) by contrast enhanced targeted biopsy and in 52 (22.6%) by systematic biopsy. Cancer was detected by targeted biopsy alone in 17 patients (7.4%) and by systematic biopsy alone in 13 (5.6%). The overall cancer detection rate by patient was not significantly different for targeted and systematic biopsy (p = 0.58). The detection rate for targeted biopsy cores (10.4% or 118 of 1,139 cores) was significantly better than for systematic biopsy cores (5.3% or 123 of 2,300 cores, p <0.001). Contrast enhanced targeted biopsy in a patient with cancer was 2.6-fold more likely to detect prostate cancer than systematic US guided biopsy. Contrast enhanced color Doppler targeted biopsy detected as many cancers as systematic biopsy with fewer than half the number of biopsy cores. Although an increase in cancer detection was achieved by combining targeted and systematic techniques in this screening population, contrast enhanced targeted biopsy alone is a reasonable approach for decreasing the number of biopsy cores.