Comparison between 3D ARFI imaging and mpMRI in detecting clinically-significant prostate cancer lesions
Current prostate cancer screening methods involve non-targeted needle biopsies and detection of clinically-insignificant lesions that receive excessive treatments, exposing patients to unnecessary adverse side effects and placing a burden on our health care systems. There is a strong clinical need for improved prostate imaging methods that are sensitive and specific for clinically-significant prostate cancer lesions to guide needle biopsies, target focal treatments, and improve overall patient outcomes. In this study, we compared 3D in vivo Acoustic Radiation Force Impulse (ARFI) imaging with 3 Tesla, endorectal coil, multi-parametric magnetic resonance imaging (mpMRI) to correlate the ability for each modality to identify clinically-significant prostate cancer lesions. We also correlated Apparent Diffusion Coefficient (ADC) values from Diffusion Weighted Imaging (DWI) MR sequences with ARFI indices of suspicion and MR Prostate Imaging - Reporting and Data Systems (PI-RADS) scores, testing the hypothesis that increased cellular density is associated with regions suspicious for prostate cancer in ARFI images. Overall, ARFI and mpMR imaging were well-correlated in identifying clinically-significant prostate cancer lesions. There were several cases where only one of the imaging modalities was able to identify the prostate cancer lesion, highlighting the potential to further improve prostate cancer lesion detection and localization with a fused ARFI:mpMRI imaging system. ADC values were decreased in all prostate cancer lesions identified with mpMRI, but there were no obvious trends between the absolute ADC values and the ARFI image indices of suspicion.