RT Journal Article SR Electronic T1 Functional Imaging of Localized Prostate Cancer Aggressiveness Using 11C-Acetate PET/CT and 1H-MR Spectroscopy JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1676 OP 1683 DO 10.2967/jnumed.110.078667 VO 51 IS 11 A1 Ivan Jambor A1 Ronald Borra A1 Jukka Kemppainen A1 Virva Lepomäki A1 Riitta Parkkola A1 Kirsti Dean A1 Kalle Alanen A1 Eveliina Arponen A1 Martti Nurmi A1 Hannu J. Aronen A1 Heikki Minn YR 2010 UL http://jnm.snmjournals.org/content/51/11/1676.abstract AB We assessed the ability of 11C-acetate PET/CT, MRI, and proton MR spectroscopy (1H-MRS) to image localized prostate cancer and detect its aggressiveness, using qualitative and quantitative approaches. Methods: Twenty-one patients with untreated localized prostate cancer, diagnosed using transrectal ultrasound-guided biopsy, were prospectively enrolled. Cancer laterality was based on the percentage of cancer and the highest Gleason score determined from biopsies. In addition to PET/CT, 3-dimensional 1H-MRS of the entire prostate volume using a quantitative approach was performed. The imaging and histologic findings of 8 patients undergoing subsequent prostatectomy were compared on a sextant level. For each lobe and sextant, standardized uptake values (SUVs) and (choline + creatine + polyamines)–to–citrate (CCP/C) ratios were obtained from 11C-acetate PET/CT and 1H-MRS, respectively. The visual and quantitative findings on PET/CT and MRI data were compared with cancer laterality and aggressiveness based on the Gleason score and with prostate-specific antigen (PSA) velocity and international risk group classification. Results: The sensitivity, specificity, and accuracy, on a lobar level using visual analysis, of 11C-acetate PET/CT were 80%, 29%, 71%, respectively, and 89%, 29%, 79%, respectively, using contrast-enhanced MRI. The sensitivity and accuracy of 11C-acetate PET/CT decreased to 64% and 63% and specificity increased to 62% when sextant analysis was performed. The agreement between prostate cancer laterality based on biopsy findings and visual interpretation of 11C-acetate PET/CT and contrast-enhanced MRI was similar at 71%. The mean SUV maximum and CCP/C maximum for the dominant tumor lesion were 5.5 and 1.48, respectively, and did not differ significantly from values in the nondominant lobe. The dominant-lesion SUVs or CCP/C values were not associated with histologically determined prostate cancer aggressiveness, nor did PSA velocity correlate with the SUV or CCP/C values from the entire gland. Conclusion: 11C-acetate PET/CT, MRI, and 1H-MRS enable detection of localized prostate cancer with comparable and limited accuracy but fail to provide information on cancer aggressiveness.