[PET/CT with (11)C-choline and (18)F-FDG in patients with elevated PSA after radical treatment of a prostate cancer].

OBJECTIVE

To compare the diagnostic accuracy of PET/CT with (18)F-FDG and (11)C-choline for early detection and localization of recurrent prostate cancer.

MATERIAL AND

METHODS

Thirty-eight patients with increased PSA levels (0.8-9.5 ng/ml) after radical treatment for prostate cancer (surgery n = 20/radiation therapy n = 18) were included. Ten patients were on hormone therapy. All patients underwent a PET/CT with (11)C-choline and (18)F-FDG, respectively, on the same day. The PET imaging findings were compared with histopathology (n = 10); PSA monitoring (n = 21) and/ or other methods (n = 7).

RESULTS

Focal uptake of (11)C-choline was detected in 26 patients (68%), and focal uptake of (18)F-FDG was detected in 13 patients (34%). The (11)C-choline uptake in 14 patients was suggested local recurrence, whereas this was true in only 4 patients (48%) with (18)F-FDG. Pelvic lymph nodes were detected with (11)C-choline PET/CT in 8 patients and only in 4 patients (50%) with (18)F-FDG. Mediastinal involvement was detected in 5 patients with (11)C-choline and 3 patients (60%) with (18)F-FDG. Focal bone involvement was detected in 3 patients with (11)C-choline and (18)F-FDG. (11)C-choline was able to detect 40% of recurrences in patients with PSA < 1 ng/ml, 50% of recurrences in patients with PSA 1-4 ng/ml and 87% of recurrences with PSA > 4 ng/ml. Sensitivity of (11)C-choline was higher for surgically treated patients, with no significant differences found between patients with and without hormone therapy.

CONCLUSIONS

(11)C-choline PET/CT was useful for the detection of biochemical recurrence of prostate cancer, with higher yielding as compared to (18)F-FDG. (11)C-choline sensitivity was clearly related to PSA levels, was higher in patients with surgery and did not seem to be modified by hormonal therapy. Disease staging with (11)C-choline showed direct impact for the selection of the most appropriate therapeutic approach.