Correlation between apparent diffusion coefficient value on diffusion-weighted MR imaging and Gleason score in prostate cancer.
OBJECTIVE
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).


METHODS
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/mm2. Both ADC and nADC were correlated with the Gleason score obtained through transrectal ultrasound-guided biopsy.


RESULTS
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±0.11×103mm2/s vs. 0.64±0.12×10-3mm2/s, P<0.05). Both the nADCminand nADCmeancorrelated 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.


CONCLUSIONS
Tumor ADCmin, nADCmin, and nADCmeanare useful markers to predict the aggressiveness of prostate cancer.
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: Xingchen.Wu@uta.fi.
X
X
Wu
Department of Oncology, Tampere University Hospital, Tampere, Finland.
P
P
Reinikainen
Department of Oncology, Tampere University Hospital, Tampere, Finland; Medical Imaging Centre, Department of Medical Physics, Tampere University Hospital, Tampere, Finland.
A
A
Vanhanen
Department of Oncology, Tampere University Hospital, Tampere, Finland; Medical Imaging Centre, Department of Medical Physics, Tampere University Hospital, Tampere, Finland.
M
M
Kapanen
Medical Imaging Centre, Department of Radiology, Tampere University Hospital, Tampere, Finland.
T
T
Vierikko
Medical Imaging Centre, Department of Radiology, Tampere University Hospital, Tampere, Finland.
P
P
Ryymin
Medical Imaging Centre, Department of Medical Physics, Tampere University Hospital, Tampere, Finland.
S
S
Hyödynmaa
Department of Oncology, Tampere University Hospital, Tampere, Finland; School of Medicine, University of Tampere, Tampere, Finland.
P-L
PL
Kellokumpu-Lehtinen
D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000473:pathology; D000368:Aged; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D061705:Image-Guided Biopsy; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D018084:Ultrasonography, Interventional
D017430:Prostate-Specific Antigen
Apparent diffusion coefficient; Diffusion-weighted imaging; Gleason score; MRI; Prostate cancer