PET/CT for the diagnosis, staging and restaging of prostate cancer

can be used for imaging trabecular changes caused by the metastasis, however, those changes appear relatively late in the course of bone metastases. Therefore, a challenge for imaging prostate cancer is to increase the diagnostic performance. Functional and molecular imaging technologies, such as PET, compared with conventional imaging, offer the possibility to image tumor-specific processes. Combined molecular and morphological imaging results in better lesion localization and characterization, corresponding to higher diagnostic accuracy. For PET and PET/CT imaging the F-labeled compound 2 ́-[F]f luoro-2 ́-deoxy-d-glucose ([F]FDG) is the most widely used tracer in oncology. PET and PET/CT with FDG have achieved a major impact in diagnostic as well as therapeutic disease management in a number of tumor entities. For the diagnosis of prostate cancer, PET and PET/CT imaging with FDG only demonstrated a limited sensitivity [3–5]. Increased FDG uptake is regularly observed only in differentiated, aggressive and metastasized prostate carcinomas. Therefore, several PET tracers for imaging prostate cancer have been introduced and evaluated in recent years, such as f luorodihydrotestosterone, acetate, methionine and radioactively labeled choline derivates [5–11]. Among these, imaging with radioactively labeled choline derivates has gained increasing importance in prostate cancer imaging. Prostate cancer is one of the most frequent cancers in men and constitutes the third most common cause of cancer deaths. Early diagnosis of primary prostate cancer, accurate staging, as well as accurate restaging in the case of cancer recurrence after primary treatment, are important for delivering the appropriate therapy. In the last ten years, functional and molecular imaging by means of PET and PET/CT are increasingly being used for such indications. This article provides a radiolabeled tracer-based review of the diagnostic value of PET and PET/CT in primary and recurrent prostate cancer. [18F]FDG, [11C]acetate, [18F]fluoride, and [18F]and [11C]choline are reviewed in this frame with an emphasis on the radiolabeled choline derivates. PET/CT with radioactively labeled choline derivates is a promising molecular imaging technique for restaging prostate cancer patients with biochemical recurrence after definite primary therapy. However, for the diagnosis of primary prostate cancer, choline PET/CT cannot be recommended at the present time.