Dynamic Contrast-enhanced MR Imaging Of The Prostatic Cancer: Correlation With Histopathologic Results

PURPOSE: To evaluate the role of dynamic contrast-enhanced magnetic resonance imaging(MRI)in the diagnose of prostatic cancer(Pca) and to determine the correlation between dynamic MRI findings with histopathologic results.MATERIALS AND METHODS: 32 patients with histopathologically verified fo Pea underwent dynamic contrast-enhanced MRI.40 patients proved to be benign prostatic hyperplasia(BPH) were performed with dynamic contrast-enhanced MRI as comparable pair.The signal intensity of leasions were analysed.The results of dynamic contrast-enhanced MRI were evaluated by early-phase enhancement parameters and time-signal intensity curves (Time-SI curves) classified according to their shapes as type I,which was steady enhancement ;type II,plateau of signal intensity;or type III,washout of signal intensity.The pathologic specimens of region of interest(ROI) were obtained after operation,which were performed H & E staning and immuno-histochemical vascular endothelial growth factor (VEGF) and microvessel density(MVD)measurements.The relationships among dynamic contrast-enhanced MRI features, H&E staning ,VEGF and MVD expression,and the prostate-specific antigen(PSA) of the patients were analyzed.RESULTS: Pea tipically appears low signal intensity in peripheral zone at T2 weighted imaging(T2WI),while the signal intensity of BPH varies according to histopathologic characters.The early-phase enhancement parameters of dynamic contrast-enhanced MRI which are onset time,maximum signal intensity and early-phase enhancement rate differ from those of BPH (p < 0.01 , 0.05, 0.01), but there are some overlap between them.The intermediate and late postcontrast periods are characterized with the lesions' Time-SI curves . The Pca Time-SI curves are mainly type III. Type II can be seen both Pca and BPH. Type I most appears in BPH.The distributions proved significantly different(p < 0.001).The mean VEGF andMVD expression of 32 Pca patients were significantly higher than those of 42 BPH patients (p < 0.001) .MVD expression of Pca and BPH showed an association with VEGF expression (p < 0.01 ) .The maximum signal intensity and early-phase enhancement rate in both Pca and BPH showed an association with MVD expression (p < 0.05 or 0.01) . There was not statistical different between PSA and early-phase enhancement parameters of Pca and BPH. PSA of Pca showed an association with MVD expression (p < 0.05) .In all 72 patients,earlier onset time,greater early-phase enhancement and Time-SI curves II and III showed an association with higher VEGF and increased MVD expression level(p < 0.05> or 0.01).There was statistical different about MVD expression level (p < 0.01), but there was not statistical different about VEGF expression level (p>0.05) separated by the mean of maximum signal intensity.If separated by 4 ng/ml of PSA level,the statistical difference appears in MVD and VEGF expression level (p < 0.01 > 0.05) .CONCLUSION: Dynamic contrast-enhanced MRI seems very useful in diagnose and differential diagnose about Pca.The characters of dynamic contrast-enhanced MRI are closely related to VEGF and MVD expression level.As a noninvasive method, dynamic contrast-enhanced MRI has a potential role in evaluating the degree of angiogenesis of Pca.