To investigate whether diffusion-weighted imaging (DWI) apparent diffusion coefficient (ADC) correlates with prostate cancer aggressiveness and further to compare the diagnostic performance of ADC and normalized ADC (nADC: normalized to non-tumor tissue).
Thirty pre-treatment patients (mean age, 69years; range: 59-78years) with prostate cancer underwent magnetic resonance imaging (MRI) examination, including DWI with three b values: 50, 400, and 800s/mm(2). Both ADC and nADC were correlated with the Gleason score obtained through transrectal ultrasound-guided biopsy.
The tumor minimum ADC (ADCmin: the lowest ADC value within tumor) had an inverse correlation with the Gleason score (r=-0.43, P<0.05), and it was lower in patients with Gleason score 3+4 than in those with Gleason score 3+3 (0.54±0.11×10(3)mm(2)/s vs. 0.64±0.12×10(-3)mm(2)/s, P<0.05). Both the nADCmin and nADCmean correlated with the Gleason score (r=-0.52 and r=-0.55, P<0.01; respectively), and they were lower in patients with Gleason score 3+4 than those with Gleason score 3+3 (P<0.01; respectively). Receiver operating characteristic (ROC) analysis showed that the area under the ROC curve was 0.765, 0.818, or 0.833 for the ADCmin, nADCmin, or nADCmean; respectively, in differentiating between Gleason score 3+4 and 3+3 tumors.
Tumor ADCmin, nADCmin, and nADCmean are useful markers to predict the aggressiveness of prostate cancer.
Diagnostic and interventional imaging. 2016 Sep 26 [Epub ahead of print]
X Wu, P Reinikainen, A Vanhanen, M Kapanen, T Vierikko, P Ryymin, S Hyödynmaa, P-L Kellokumpu-Lehtinen
Department of Oncology, Tampere University Hospital, Tampere, Finland; Medical Imaging Centre, Department of Radiology, Tampere University Hospital, Tampere, Finland; School of Medicine, University of Tampere, Tampere, Finland. Electronic address: ., Department of Oncology, Tampere University Hospital, Tampere, Finland., Department of Oncology, Tampere University Hospital, Tampere, Finland; Medical Imaging Centre, Department of Medical Physics, Tampere University Hospital, Tampere, Finland., Medical Imaging Centre, Department of Radiology, Tampere University Hospital, Tampere, Finland., Medical Imaging Centre, Department of Medical Physics, Tampere University Hospital, Tampere, Finland., Department of Oncology, Tampere University Hospital, Tampere, Finland; School of Medicine, University of Tampere, Tampere, Finland.