Targeted biopsy of the prostate: the impact of color Doppler imaging and elastography on prostate cancer detection and Gleason score.

OBJECTIVES

To compare detection of prostate cancer and distribution of Gleason scores with gray-scale, color Doppler, and elastographic imaging.

METHODS

Prostate biopsy patients were evaluated with gray-scale, color Doppler, and elastographic imaging. Targeted biopsy cores were obtained along with six laterally directed systematic sextant cores. Pathologic results were correlated with imaging findings.

RESULTS

Prostate cancer was detected in 60 of 137 patients (43.8%). Cancer was detected in 241 (14%) of 1703 biopsy cores, including 90 (20%) of 448 targeted cores, 106 (13%) of 818 sextant cores, and 45 (10%) of 437 transition zone cores. Sonographic abnormality was associated with cancer: gray-scale odds ratio (OR) = 3.19, P = 0.011; color Doppler OR = 1.86, P = 0.041; elastography OR = 2.53; P = 0.007. Although targeted cores were more likely than sextant cores to detect cancer (OR = 1.82, P = 0.004), no sonographic abnormality was found in 57 (53.8%) of 106 of positive sextant sites. A linear trend for increasing Gleason score was present with gray-scale (P <0.001) imaging, color Doppler imaging (P <0.005), and elastography (P <0.001). Abnormal color flow was strongly associated with Gleason score 8 to 10 lesions but not with lower-grade lesions. Elastography demonstrated a positive association with Gleason scores of 5 to 10.

CONCLUSIONS

Targeted cores based on gray-scale, color Doppler, and elastographic imaging are more likely to return positive biopsy results as compared with systematic biopsy cores. Although color Doppler imaging and elastography are encouraging adjuncts to improve cancer detection, targeted biopsy alone is not sufficient to replace the traditional sextant biopsy technique.