The potential of FDG-PET/CT for detecting prostate cancer in patients with an elevated serum PSA level

The aim of this study is to evaluate the potential and limitation of FDG-PET/CT for detecting prostate cancer in subjects with an elevated serum prostate-specific antigen (PSA) level. Although [F-18]-2-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) has limited value in detecting prostate cancer, the potential of PET/CT has not been precisely evaluated, since positron emission tomography/computed tomography (PET/CT) provides accurate localization of functional findings obtained by PET. Subjects with an increasing PSA level suggestive of prostate cancer were enrolled in this study. FDG-PET/CT was performed prior to prostate biopsy and the findings were compared with the pathological results. Fifty subjects with an elevated serum PSA level took part in this study. The sensitivity, specificity and positive predictive value (PPV) of FDG-PET/CT in the prostate were 51.9% (27/52 areas), 75.7% (112/148 areas) and 42.9% (27/63 areas), respectively; those in the peripheral zone were 73.3% (22/30 areas), 64.3% (45/70 areas) and 46.8% (22/47 areas), respectively; and those in the central gland were 22.7% (5/22 areas), 85.9% (67/78 areas) and 31.3% (5/16 areas), respectively. The estimated cut-off values according to the highest odds ratio (OR) were age of 70 years [OR: 7.00, 95% confidence interval (CI): 1.89-25.93] and a PSA value of 12.0 ng/ml (OR: 10.77, 95% CI: 2.78-41.74). The FDG-PET/CT could potentially detect cancer with 80.0% sensitivity and 87.0% PPV in cases with a Gleason score of 7 or greater. FDG-PET/CT was appropriate for detecting peripheral zone prostate cancer in patients at more than an intermediate risk.