The diagnosis of prostate cancer is currently limited by the low sensitivity and specificity of systematic conventional grey-scale ultrasonography. We assessed contrast-enhanced colour Doppler ultrasonography by means of a microbubble ultrasound contrast agent to detect tumour vascularity and improve the diagnosis of prostate cancer. The use of a microbubble ultrasound contrast agent for transrectal colour Doppler targeted biopsy significantly improved the detection of prostate cancer compared with systematic biopsy following conventional grey-scale ultrasonography (p<0.001). Contrast-agent enhanced colour Doppler imaging may allow for limited targeted biopsies (five or less), which reduces costs and morbidity.