Prostatic cancer: role of color Doppler imaging in transrectal sonography.

Abstract
The aim of this study was to assess the roles of transrectal color Doppler and gray-scale sonography in revealing prostatic cancer, using biopsy as the reference standard. Two hundred fifty-six patients referred for urologic studies underwent transrectal sonography using gray-scale and color Doppler scanning. All abnormal areas shown on gray-scale or color Doppler sonography or both were targeted and biopsies were performed. The patients also underwent random sextant biopsies. All biopsies were individually correlated with histopathologic findings and all results were analyzed. Cancer was found on biopsy in 100 patients (39%), and equivocal sonographic results or prostatic intraepithelial neoplasia was found in 22 other patients (9%). In 16 of the patients in whom cancer was detected, the tumors were correctly revealed only with color Doppler sonography. These 16 patients had a mean Gleason score of 6.4 (range, 5-8). Biopsy findings in these 16 patients showed eight patients with extensive lesions, three with moderate lesions, and five with minimal lesions. However, in nine other patients with cancer (9% of cancers detected), both gray-scale and color Doppler sonography failed to reveal lesions that were found on sextant biopsy. An analysis showed that, although highly sensitive, color Doppler sonography was somewhat less specific than gray-scale sonography. Color Doppler sonography should become a routine part of transrectal sonography of the prostate gland to improve detection and targeting of lesions. The practice of performing random sextant biopsies should also continue.