Prostate Cancer Detection With 3.0T MRI:Diagnostic Efficacy Of T2WI,DWI And DCE-MRI

Objective To investigate the applying value of T2-weighted imaging,diffusion weighted imaging,dynamic contrast-enhanced MRI and the combination of the three MR techniques in the diagnosis of prostate cancer.To develop a multi-parametric model suitable for prospectively identifying prostate cancer using MRI.Methods 178 patients had T2-weighted,DWI,and DCE(without T1-mapping)MRI at 3.0 T with body coil to yield parameters T2 score,ADC,SI-T curve,Ktrans,Kep and Ve.Eighty-two patients' diagnosis was confirmed by histopathology through systematic transrectal prostate biopsy or radical prostatectomy.All parameters in different tissue(cancerous foci,noncancerous foci in the peripheral zone and central gland)were compared with ANOVA.Receive operating characteristic(ROC)curve were generated using all identified normal and tumor voxels,and used to determine the threshold of malignant,its sensitivity,specificity as well as accuracy were calculated respectively.Step-wise logistic-regression modeling was performed,testing changes in deviance for significance,and used to evaluate and compare performance.Results All the 984 sextants from 82 cases were confirmed by biopsies,the T2 score,ADC,Ktrans,Kep and Ve values of cancerous foci were 4.27 points,(0.738±0.168)x10-3mm2/s,(1.002±0.491)/min,(1.533±0.795)/min,(0.679±0.164),respectively,while 2.10 points,(1.562±0.371)×10-3mm2/s,(0.366±0.203)/min,(0.591±0.297)/min,(0.648±0.181)for noncancerous foci in the peripheral zone and 1.89 points,(1.266±0.228)x 10-3mm2/s,(0.575±0.273)/min,(0.803±0.356)/min,(0.734±0.136)for noncancerous foci in the central gland.The differences on T2 score,ADC,Ktrans and Kep parameters between cancerous foci,noncancerous foci in the peripheral zone and central gland were statistically significant(P=0.000,respectively),and no significant differences on T2 score between noncancerous foci in the peripheral zone and central gland,and Ve parameters between noncancerous foci in the central gland and the other two foci(P>0.05).The sensitivity,specificity and accuracy for the detection of prostate cancer were 80.3%,87.7%and 89.9%for T2WI,as the cutoff was 3.5;92.6%,98.8%and 97.1%for ADC values,as the cutoff was 0.967×10-3mm2/s;77.4%,75.8%,85.2%for Ktrans,as the cutoff was 0.626/min;and 83.1%,79.4%,89.9%for Kep,as the cutoff was 0.930/min,98.8%,96.6%,98.1%for the combining application of the three examination methods,respectively.Conclusion Conventional MRI is helpful for discovering and staging prostate cancer,but qualitative diagnosis is somewhat lacking.The best-performing single-parameter was ADC.DCE-MRI provides complementary information in qualitative diagnosis,SI-T curve and Kep is contributing to the overall goodness of fit of the model.Prostate cancer can be diagnosed effectively by the combining application of T2WI,DWI and DCE-MRI,and can develop a multi-parametric model suitable for prospectively identifying prostate cancer using MRI.