Prostate Contrast Enhanced Transrectal Ultrasound Evaluation of the Prostate With Whole-Mount Prostatectomy Correlation.

OBJECTIVE

To investigate the diagnostic accuracy of contrast enhanced transrectal ultrasound (CE-TRUS) in comparison with whole-mount radical prostatectomy specimens.

METHOD AND MATERIALS

Fifty-eight subjects who underwent CE-TRUS and subsequent radical prostatectomy with whole-mount pathology were included in the study. Each patient underwent evaluation with baseline TRUS and again during CE-TRUS with intravenous infusion of perflutren lipid microsphere (Definity, Lantheus Medical Imaging, N Billerica, MA). A subjective 5 point scale was used to rate each sextant of the prostate in 3 baseline imaging modes and in 5 contrast-enhanced imaging modes. Baseline TRUS and CE-TRUS findings were compared with digitized whole-mount findings. A clustered logistic regression model was computed to compare the area under the receiver operating characteristic curve (A) for detection of prostate cancer by various modes of ultrasound imaging.

RESULTS

Among the 58 whole-mount specimens, a maximum Gleason score of 6 was identified in 29 subjects, a score of 7 was identified in 24 and a score of 8 was identified in 5. The A for baseline TRUS parameters was 0.55 for grayscale, 0.61 for color Doppler and 0.59 for power Doppler. CE-TRUS parameters demonstrated significant increases in A with the highest A for CE-power Doppler (0.66) and flash replenishment imaging (0.64) (P = .04 for comparison to baseline). The combination of CE-power Doppler and flash replenishment imaging resulted in improved A compared with baseline imaging (0.70 vs 0.59, P= .006).

CONCLUSION

Contrast-enhanced ultrasonography demonstrates greater diagnostic accuracy than baseline imaging. Diagnostic accuracy is further improved for "clinically significant" tumor volumes >1 cc.