Value of contrast-enhanced ultrasonography in prostate cancer

Abstract

Purpose of review: Traditional grayscale ultrasonography has poor discrimination between benign and malignant areas within the prostate. Current biopsy techniques commonly miss prostate cancer when present within the gland, with the majority of prostate biopsies negative for cancer. Enhanced ultrasound (US) modalities may improve the visualization of the prostate and better detect foci of prostate cancer. These enhanced US modalities include intravenous contrast enhancement, to better visualize areas with increased blood flow within the prostate, which may be indicative of latent prostate cancer. We reviewed the current literature for contrast-enhanced transrectal prostate ultrasonography.

Recent findings: Numerous American and international studies demonstrate improved prostate cancer detection when contrast-enhanced US biopsy techniques are used. Enhanced US modalities include the use of harmonic imaging and flash replenishment techniques, as well as quantitative measurement of blood flow within the prostate. Vascular areas visualized with these techniques targeted for prostate biopsy yield improved prostate cancer detection rates. US contrast microbubbles linked to antibodies or small molecules may also allow targeted visualization and delivery of agents to the prostate.

Summary: Enhanced US modalities with intravenous contrast enhancement dramatically improve vascular imaging and resolution within the prostate. Targeted biopsies have higher yield for prostate cancer detection, and may prove useful for the initial evaluation of patients with elevated serum prostate-specific antigen levels, as well as for patients with persistently elevated prostate-specific antigen after negative prostate biopsy.