Aim: The purpose of this preliminary study was to evaluate the usefulness of 11C-choline PET/CT in patients with recurrent prostate cancer and hormone-sensitive disease treated with intermittent antiandrogen therapy scheme.
Patients and Methods: We retrospectively evaluated 10 patients after radical prostatectomy (n = 8) or external beam radiotherapy (n = 2) as primary therapy, studied with sequential 11C-choline PET/CT. The first PET/CT (PET1) was performed during antiandrogen therapy (ADT) and the second PET/CT (PET2) was performed after therapy interruption. Only patients with negative results at PET1 were included in the study. At the time of PET1, all patients were under ADT from at least 6 months (mean PSA 0.54 ng/mL). At the time of PET2, all patients had completed ADT for a mean period of 7 months. 11C-Choline PET/CT findings were validated by a follow-up of at least 12 months or histological confirmation in case of local relapse.
Results: PET2 has been able to detect the site of recurrences in all cases. At the time of PET2, mean PSA was 3.88 ng/mL; mean PSAdt was 2.46 months; and mean PSAvel was 6.94 ng/mL/year. Four out of 10 patients showed a single lesion, 5 out of 10 patients showed 2 lesions and 1 patient showed multiple lymph-node lesions.
Conclusion: When performed during ADT interruption, 11C-choline PET/CT has been able to detect the site of recurrence in patients with increasing PSA values. In this context, 11C-choline PET/CT may help to assess the burden of disease or to change the therapeutic approach using more aggressive and addressed therapies like guided RT or salvage lymph-node dissection.
From the *Nuclear Medicine Unit, Department of Haematology Oncology and Laboratory Medicine and †Department of Urology, Azienda Ospedaliero—Universitaria di Bologna, Policlinico Sant’Orsola–Malpighi, University of Bologna, Bologna, Italy; ‡Nuclear Medicine Unit, Fondazione Salvatore Maugeri, Pavia, Italy; §Department of Radiology, University of Southern California, Los Angeles, CA; and ¶Department of Nuclear Medicine & PET/CT Centre, Santa Maria della Misericordia Hospital, Rovigo, Italy.
Received for publication February 11, 2013; and revision accepted March 20, 2013.
Conflicts of interest and sources of funding: none declared.
Reprints: Domenico Rubello, MD, Department of Imaging, Head Service Nuclear Medicine & PET/CT Centre, Santa Maria della Misericordia Hospital, Rovigo, Italy. E-mail: email@example.com.