Volume 54, Issue 3, Pages 589-600 (September 2008) Role of Dynamic Contrast-Enhanced Magnetic Resonance (MR) Imaging and Proton MR Spectroscopic Imaging in the Detection of Local Recurrence after Radical Prostatectomy for Prostate Cancer  Alessandro Sciarra, Valeria Panebianco, Stefano Salciccia, Marcello Osimani, Danilo Lisi, Mauro Ciccariello, Roberto Passariello, Franco Di Silverio, Vincenzo Gentile  European Urology  Volume 54, Issue 3, Pages 589-600 (September 2008) DOI: 10.1016/j.eururo.2007.12.034 Copyright © 2007 European Association of Urology Terms and Conditions

Fig. 1 Images in a patient with prostate-specific antigen progression after radical prostatectomy, suspected for local recurrence (group A). (A) Transverse T2-weighted fast spin-echo (repetition time (TR), 5190 ms; echo time (TE), 95 ms) magnetic resonance (MR) images show intermediate-signal-intensity mass (arrow) in a periurethral location, suspected for local recurrence, with poor depiction of the borders. (B) B’ shows positioning of the volume of interest for MR spectroscopic analysis with three-dimensional chemical shift imaging sequences superimposed on T2-weighted images; in (B), voxel analysis curve shows markedly reduced citrate (Ci) signal and increased choline-creatine to citrate ratio (Cho+Cr/Cit >2) in the area with intermediate signal intensity on T2-weighted images. Three-dimensional fast low-angle shot (FLASH) T1-weighted spoiled gradient-echo image (C) shows a well-defined hypervascular lesion (arrows) relative to the surrounding noncancerous tissue, with excellent depiction of the tumor border. In (D), the corresponding MR signal enhancement-time curve shows a significant difference between pelvic muscle enhancement (region of interest [ROI] 1) and the smaller time to peak and higher peak enhancement values of suspected area (ROI 2). Recurrent carcinoma was histologically validated at transrectal ultrasound-guided biopsy. European Urology 2008 54, 589-600DOI: (10.1016/j.eururo.2007.12.034) Copyright © 2007 European Association of Urology Terms and Conditions

Fig. 2 Graphs show receiver operating characteristic (ROC) curves comparison for each analysis phase. In (A), ROC curves calculated in the first patient group (group A) show area under the curve (AUC) values for magnetic resonance (MR) spectroscopic imaging (first-phase analysis), dynamic (second-phase analysis), and evaluation of both dynamic and MR spectroscopic imaging (third-phase analysis). AUC was significantly greater in third-phase analysis than with spectroscopic and dynamic imaging, confirming a significantly better performance of the combined MR spectroscopic imaging/dynamic contrast-enhanced MR (1H-MRSI/DCEMR) evaluation of cancer recurrence localization. (1H-MRSI=0.942±SE 0.033, DCEMR=0.931±0.036. 1H-MRSI+DCEMR=0.964±SE 0.026). In (B), ROC curves calculated in the second patient group (group B) show AUC significantly greater with combined evaluation of both spectroscopic and dynamic findings than with spectroscopic and dynamic imaging alone. In contrast to group A, the spectroscopic evaluation show a lower performance level (a smaller AUC) than dynamic evaluation. Base model included an analysis of choline (Cho) plus creatine (Cr) to citrate (Ci) ratio>0.5 and < 1 (cut off, ≥0.5) for spectroscopic images and parameters evaluated by different area under the receiver operating characteristic curve (AUC) for DCEMRI. Diagonal line indicates area under ROC curve of 0.500. (1H-MRSI=0.810±SE 0.099, DCEMR=0.923±0.061, 1H-MRSI+DCEMR=0.940±SE 0.053). See Table 3 for numerical results. European Urology 2008 54, 589-600DOI: (10.1016/j.eururo.2007.12.034) Copyright © 2007 European Association of Urology Terms and Conditions

Fig. 3 Images in a patient with prostate-specific antigen (PSA) progression after radical prostectomy, suspected for local recurrence (group B). (A) Transverse T2-weighted fast spin-echo (repetition time (TR), 5190ms, echo time (TE), 95ms) images show a mass of intermediate signal intensity (arrow) in a periurethral location, suspected for local recurrence; (B) B’ shows the positioning (with low signal-to-noise ratio) of the volume of interest for magnetic resonance (MR) spectroscopic analysis with three-dimensional (3D) chemical shift imaging sequences on referenced T2-weighted image; in (B), voxel analysis curve show markedly reduced citrate (Ci) signal and increased choline-creatine to citrate ratio (Cho+Cr/Cit=2.72) (Ci value to be considered as value in the ratio) in an area with intermediate signal intensity on T2-weighted images. 3D fast low-angle shot (FLASH) T1-weighted spoiled gradient-echo image (C) shows a well-defined hypervascular lesion (arrows) relative to the surrounding noncancerous peripheral zone, with excellent depiction of the tumor border. In (C’), the corresponding MR signal enhancement-time curve shows a significant difference between pelvic muscle enhancement (region of interest [ROI] 1) and the smaller time to peak and higher peak enhancement values of suspected area and rapid washout (ROI 2). This finding suggests a local cancer recurrence of 7mm. In this patient recurrent carcinoma was validated by a PSA serum level decrease after external beam radiotherapy (<0.2ng/ml). European Urology 2008 54, 589-600DOI: (10.1016/j.eururo.2007.12.034) Copyright © 2007 European Association of Urology Terms and Conditions