We assessed the value of fusion (18)F-fluoromethylcholine ((18)F-choline) Positron Emission To-mography / Magnetic Resonance Imaging (PET/MRI) for image-guided (targeted) prostate biop-sies to detect significant prostate cancer (Gleason ≥ 3+4) compared to standard (systematic 12-core) biopsies.
Within an ongoing prospective clinical trial, hybrid (18)F-choline Positron Emission Tomography / Computed Tomography (PET/CT) and multi-parametric 3T MRI (mpMRI) of the pelvis were performed in 36 subjects with rising prostate specific antigen (PSA) for known (n = 15) or suspected (n = 21) prostate cancer prior to a prostate biopsy procedure. PET and T2-weighted (T2w) Magnetic Resonance (MR) volumes of the prostate were spatially registered using commercially available software. Biopsy targets were selected based on visual appearance on MRI and graded as low, intermediate or high risk for significant disease. Volumes of interest (VOI) were defined for MR-identified lesions. (18)F-choline uptake measures were obtained from the MR-target and a mirrored background VOI. The biopsy procedure was performed after registration of real-time transrectal ultrasound (TRUS) with T2w MR and included image-guided cores plus standard cores. Histological results were determined from standard and targeted biopsy cores, as well as prostatectomy specimens (n = 10).
Fifteen subjects were ultimately identified with Gleason ≥ 3+4 prostate cancer, of which targeted biopsy identified significantly more (n = 12) than standard biopsies (n = 5; P = 0.002). A total of 52 lesions were identified by mpMRI (19 low; 18 intermediate; 15 high risk), and mpMRI-assigned risk was a strong predictor of final pathology (area under the curve (AUC) = 0.81; P < 0.001). Using the mean (18)F-choline target-to-background ratio (TBR), the addition of (18)F-choline to mpMRI significantly improved the prediction of Gleason ≥ 3+4 cancers over mpMRI alone (AUC = 0.92; p<0.001).
Fusion PET/MRI-TRUS image registration for targeted prostate biopsies is clinically feasible and accurate. The addition of (18)F-choline PET to mpMRI improves identification of significant prostate cancer.
Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2016 Mar 16 [Epub ahead of print]
Morand Piert, Jeffrey Montgomery, Lakshmi Priya Kunju, Javed Siddiqui, Virginia Rogers, Thekkelnaycke Rajendiran, Timothy D Johnson, Xia Shao, Matthew S Davenport
University of Michigan, United States., University of Michigan, United States., University of Michigan, United States., University of Michigan, United States., University of Michigan, United States., University of Michigan, United States., University of Michigan, United States., University of Michigan, United States., University of Michigan, United States.