Evaluation of suspected soft tissue lesion in the prostate bed after radical prostatectomy using 3 T multiparametric magnetic resonance imaging

PurposeTo investigate the usefulness of multiparametric MR imaging (mp-MRI) at 3 T for evaluating suspected soft tissue lesion in the prostate bed after radical prostatectomy (RP).Materials and methodsForty-three patients with biochemical recurrence (BCR) who received RP underwent mp-MRI at 3 T with a phased-array coil, including T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI) and dynamic contrast-enhanced imaging (DCE-MRI) and were enrolled in this study. All patients with BCR had a suspected soft tissue lesion in the prostate bed, followed by transrectal ultrasound-guided biopsy. As a control group, 14 consecutive patients without BCR who received RP were also enrolled. Two experienced radiologists independently analyzed four different imaging datasets.ResultsFor predicting local recurrence, the specificity, accuracy and area under the curve for both readers were significantly greater on all combined imaging datasets than on T2WI alone (P < 0.05). The sensitivity of all combined imaging datasets in both readers was not statistically different with T2WI alone (P > 0.05), except for combined T2WI and DWI. Inter-reader agreements for the four different imaging datasets were moderate.ConclusionDCE-MRI or DWI in combination with T2WI at 3 T with a phased-array coil appears to be more useful than T2WI alone in evaluating suspected soft tissue lesion of the prostate bed after RP.