Utility of computed diffusion-weighted MRI for predicting aggressiveness of prostate cancer

To investigate the value of computed (c) diffusion-weighted imaging (DWI) in assessing prostate cancer aggressiveness.

Fifty-five patients with peripheral zone prostate cancer who underwent prebiopsy 1. 5T magnetic resonance imaging (including native DWI at b-values of 0 and 1000 s/mm(2) ) were included. cDWI signal intensities of peripheral zone prostate cancer and nonmalignant prostate tissue were measured. Association between changes in monoexponentially calculated cDWI signals according to different b-values and primary Gleason grades were assessed.

The cDWI signal intensity of prostate cancer was lower at b = 0 s/mm(2) and higher at b = 1000 s/mm(2) compared to nonmalignant prostate tissue. The b-value at which the signal intensities of prostate cancer and nonmalignant prostate tissue were equal was defined as the "iso-b-value." On multivariate analysis, only the iso-b-value was a significant predictor of primary Gleason grade 4/5 cancer (P = 0.001). The area under the curve (AUC) of the iso-b-value for diagnosing primary Gleason grade 4/5 cancer was 0.94, and significantly higher than that of the tumor apparent diffusion coefficient (ADC) value with an AUC of 0.68 (P < 0.001).

cDWI with iso-b-value-based semiquantitative analysis was found to be useful for predicting the aggressiveness of prostate cancer and may potentially outperform tumor ADC measurements in this setting.

3 J. Magn. Reson. Imaging 2017.

Journal of magnetic resonance imaging : JMRI. 2017 Feb 02 [Epub ahead of print]

Yuma Waseda, Soichiro Yoshida, Taro Takahara, Thomas Christian Kwee, Yoh Matsuoka, Kazutaka Saito, Kazunori Kihara, Yasuhisa Fujii

Urology, Tokyo Medical and Dental University Graduate School, Tokyo, Japan., Biomedical Engineering, Tokai University School of Engineering, Kanagawa, Japan., Department of Radiology, University Medical Center Groningen, Groningen, Netherlands.