18F-Fluorocholine PET/CT Complementing the Role of Dynamic Contrast-Enhanced MRI for Providing Comprehensive Diagnostic Workup in Prostate Cancer Patients With Suspected Relapse Following Radical Prostatectomy

Purpose: The aim of this study was to compare the diagnostic performance of F-18-fluorocholine (FCH) PET/CT and dynamic contrast-enhanced MRI (DCE-MRI) of pelvis in restaging prostate cancer (PC) patients with biochemical recurrence (BCR) following radical prostatectomy (RP). Methods: Twenty PC patients who had undergone RP and had BCR were recruited in this study. All the patients underwent whole-body FCH PET/CT and DCE-MRI of the pelvis. An overall pattern of recurrent disease was analyzed, and diagnostic accuracy for the detection of pelvic disease recurrence by the 2 modalities was evaluated by taking histopathologic analysis as the criterion standard. The whole-body FCH PET/CT images were also analyzed separately for the presence of any extra lesion(s). Results: The initial mean Gleason score was 6.3 +/- 1.53 (range, 4-9). The mean prostate-specific antigen levels at the time of relapse were 1.9 +/- 2.87 ng/mL (range, 0.24-13.2 ng/mL). MRI findings were positive for primary tumor recurrence in the prostate bed in 6 patients (6/20 [30.0%]), pelvic lymph node metastases in 4 patients (4/20 [20.0%]), and for pelvic skeletal metastases in 2 patients (2/20 [10.0%]), respectively. On the other hand, FCH PET/CT results were positive in the corresponding sites in 7 (7/20 [35.0%]), 9 (9/20 [45.0%]), and 2 patients (2/20 [10.0%]), respectively. F-18-fluorocholine PET/CT and MRI showed comparable results in terms of sensitivity, specificity, and positive and negative predictive values for PC characterization. The whole-body FCH PET/CT was found to be useful in identifying unknown distant metastases in a significant proportion of patients. Conclusions: The correlative whole-body FCH PET/CT and pelvic DCE-MRI offer a complementary and comprehensive diagnostic workup for better management of PC patients with BCR following RP.