The ability of 11C-choline and multimodality fusion imaging with integrated PET and contrast-enhanced CT (PET/CT) was investigated to delineate prostate carcinoma (PCa) within the prostate and to differentiate cancer tissue from normal prostate, benign prostate hyperplasia, and focal chronic prostatitis.
Methods: All patients with PCa gave written informed consent. Twenty-six patients with clinical stage T1, T2, or T3 and biopsy-proven PCa underwent 11C-choline PET/CT after intravenous injection of 1,112 +/- 131 MBq 11C-choline, radical retropubic prostatovesiculectomy, and standardized prostate tissue sampling. Maximal standardized uptake values (SUVs) of 11C-choline within 36 segments of the prostate were determined. PET/CT results were correlated with histopathologic results, prostate-specific antigen (PSA), Gleason score, and pT stage.
Results: The SUV of 11C-choline in PCa tissue was 3.5 +/- 1.3 (mean +/- SD) and significantly higher than that in prostate tissue with benign histopathologic lesions (2.0 +/- 0.6; P < 0.001 benign histopathology vs. cancer). Visual and quantitative analyses of segmental 11C-choline uptake of each patient unambiguously located PCa in 26 of 26 patients and 25 of 26 patients, respectively. A threshold SUV of 2.65 yielded an area under the receiver-operating-characteristic (ROC) curve of 0.89 +/- 0.01 for correctly locating PCa. The maximal 11C-choline SUV did not correlate significantly with PSA or Gleason score but did correlate with T stage (P = 0.01; Spearman r = 0.49).
Conclusion: 11C-Choline PET/CT can accurately detect and locate major areas with PCa and differentiate segments with PCa from those with benign hyperplasia, chronic prostatitis, or normal prostate tissue. The maximal tumoral 11C-choline uptake is related to pT stage.