Preliminary Investigation: Diagnostic Differentiation Of Prostate Cancer From Prostatic Hyperplasia

Objective: To evaluate the feasibility of the typical parameters of diffusion kurtosis imaging(DKI), MK, Ka, Kr, FA, MD, Da, Dr, in diagnositic differentiation of prostatic carcinoma(PCa) from benign prostatic hyperplasia(BPH). Materials and Methods: One hundred and thirteen patients with the suspicion of prostate disease were recruited in the study. All the patients, with written informed consent obtained, were performed MRI exams on a 3.0T scanner(GE-Signa HDXT) in a protocol containing the routine T1 WI, T2 WI, contrast-enhanced MRI, DWI(b=0, 1000s/mm2) and DKI(b =0, 1000 and 2000 s/mm2, in 15 directions). From the following histopathological examination, it was confirmed that prostate carcinoma was in 30 and prostatic hyperplasia in 29. MR images were reviewed and analyzed by author and one experienced radiologist who has five years experience in prostate diagnosis, using a dedicated software in Functool on GE ADW4.4 workstation, and two observers were blinded to the histopathological results. For each focus, the mean value of the parameters of DKI(MK, Ka, Kr, FA, MD, Da, Dr) and DWI(ADC) was measured: in PCa group, the area where shows low signal on T2 WI image, high signal on MK image and histopathological positive was the focus, regions of interest(ROIs) drew three times in the tumor, the size of the ROI was chosen to cover the 2/3 of the tumor, then the average value was used in statistics. In BPH group, three identical ROIs(70mm2)were drew in the central zone, the average value was used in statistics. The type of time-signal intensity curve(TIC) was observed by two observers collectively. ICC test was used to examine the consistency of the measurements, Pearson test was used to examine the relevance between MD and ADC value,and student’s t-test was executed to compare the obtained parametric values with p> 0.05 concerned statistical significant. The ROC curve of all the parameters were drew and analyzed. Results: The ICC value of the DKI parameters(MK, Ka, Kr, FA, MD, Da, Dr) and DWI parameter(ADC) in the PCa group and BPH group were respectively, 0.963、0.935、0.959、0.905、0.970、0.909、0.967、0.977 and 0.804、0.899、0.913、0.901、0.923、0.902、0.911、0.931, exhibiting an amenable consistency. The mean MK, Ka, Kr of PCa were significantly higher(p < 0.01) than the BPH, while the mean MD, Da, Dr of cancerous tissue was found to be significantly lower(p < 0.01) than the hyperplasia tissue. No statistically significant difference was observed between FA values of two groups(p >0.05). The area under the ROC curve of all parameters were higher than 0.9. Conclusion: DKI demonstrated can supply many meritorious parameters, with most useful in diagnostic differentiation of prostate cancer from prostatic hyperplasia. Combining with the routine prostate MRI, DKI may help in increasing the sensitivity and specificity of cancer detection.