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

Abstract

Purpose: 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 [¹⁸F]-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.

Methods: 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.

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.

Conclusion: FDG-PET/CT was appropriate for detecting peripheral zone prostate cancer in patients at more than an intermediate risk.