Adding contrast improves ultrasound's ability to detect prostate cancer

Contrast enhanced color Doppler ultrasound is better than unenhanced ultrasound at detecting prostate cancer, according to a report published in the July issue of The Journal of Urology.
Doctors in France, compared the diagnostic abilities of contrast enhanced and unenhanced endo-rectal ultrasound in 85 men suspected of having prostate cancer. In all subjects, the imaging findings were compared with biopsy results. Fifty-eight biopsy sites in 54 patients showed cancer on histologic analysis, the researchers note.

Of the 96 suspicious areas detected with gray scale ultrasound, only 48 were found to be malignant on pathologic examination. Unenhanced color ultrasound was 54% sensitive and 79% specific in detecting prostate cancer. With contrast, however, the sensitivity and, to a lesser extent, the specificity improved to 93% and 87%, respectively.

Of 10 positive cases of isoechoic zones, nine were detected by contrast-enhanced ultrasound, while only seven were detected by unenhanced US, the investigators point out.

"Contrast-enhanced [ultrasound] improves the positive biopsy rate of prostate cancer with the addition of directed biopsy cores," say doctors. Moreover, "it seems to be a reasonable and cost-effective alternative to the current standard of care," they add.