Imaging prostate cancer with ¹¹C-choline PET/CT

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.