Jean-Michel Correas MD, Presenter: Advisory Board, Koninklijke Philips Electronics NV Speaker, Bracco Group Investigator, Bracco Group Speaker, SuperSonic Imagine Speaker, General Electric Company

Ahmed Khairoune, Abstract Co-Author: Nothing to Disclose

Anne-Marie Tissier MD, Abstract Co-Author: Nothing to Disclose

Viorel Vassiliu MD, Abstract Co-Author: Nothing to Disclose

Arnaud Méjean MD,PhD, Abstract Co-Author: Nothing to Disclose

Claude Cohen Bacrie MD, PhD, Abstract Co-Author: Executive Vice President, SuperSonic Imagine Officer, SuperSonic Imagine

Olivier Hélénon, Abstract Co-Author: Nothing to Disclose

The purpose of this study was to evaluate the feasibility of real time TransRectal UltraSound (TRUS) quantitative Shear Wave Elastography (SWE) imaging for prostate lesion characterization.

31 patients presenting increased PSA values (4-10 ng/mL) were prospectively enrolled after signing an informed consent form. The prostate was studied using trans-rectal ultrasound (TRUS) with spatial compounded B-mode, Color Doppler UltraSound (CDUS), and SWE with an Aixplorer ultrasound system (Supersonic Imagine, Aix-en-Provence, France). Elasticity measurements in KPascal and ratios between nodules and adjacent parenchyma were calculated. Contrast-Enhanced US (CEUS) was performed using low MI pulse subtraction after injection of 4.8 ml of SonoVue® (Bracco, Milan, Italy). Imaging findings were correlated to sextant prostate biopsies (n=12) and targeted biopsies on suspicious areas (n=2-6) detected at SWE and CEUS. MRI with axial and coronal T2w acquisition, axial T1w acquisition, diffusion and dynamic contrastenhanced MRI was also evaluated.

Among the 39 nodules detected either at ultrasound imaging or at pathology, 14 were adenocarcinomas with Gleason score above 6 and 25 were adenomatous hyperplasia or focal prostatitis. Prostate cancer nodules exhibited higher stiffness (mean 58±48 kPa) than the adjacent peripheral gland (mean 20±10 kPa). The stiffness ratio between nodule and adjacent parenchyma was significantly higher for cancer (3.0±1.0) compared to benign nodules (1.0±0.20; p< 0.01). The ratio cutoff value of 1.5 allowed the best discrimination of the two populations. The Sensitivity (Se), Specificity (Spe), Positive Predictive Value (PPV) and Negative Predictive Value (NPV) were calculated for each modality: CDUS, CEUS, SWE ratio (with 1.5 cutoff) and MRI. CDUS: Se= 55%; Spe= 76%; PPV= 55%; NPV= 76%. CEUS: Se= 70%; Spe= 80%; PPV= 70%; NPV= 80%. SWE ratio: Se= 85%; Spe= 90%; PPV= 85%; NPV= 90%. MRI: Se= 73%; Spe= 75%; PPV= 56%; NPV= 82%

TRUS SWE has large potentials for the characterization of prostate nodules. These preliminary results must be confirmed by a multi centric clinical trial.  

TRUS SWE demonstrates potential for prostate nodule characterization.

Correas, J, Khairoune, A, Tissier, A, Vassiliu, V, Méjean, A, Cohen Bacrie, C, Hélénon, O, Transrectal Ultrasound Quantitative Shear Wave Elastrography: Application to Prostate Nodule Characterization&mdash;A Feasibility Study.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11012384.html