Imaging techniques for prostate cancer: implications for focal therapy.

The multifocal nature of prostate cancer has necessitated whole-gland therapy in the past; however, since the widespread use of PSA screening, patients frequently present with less-advanced disease. Many men with localized disease wish to avoid the adverse effects of whole-gland therapy; therefore, focal therapy for prostate cancer is being considered as a treatment option. For focal treatment to be viable, accurate imaging is required for diagnosis, staging, and monitoring of treatment. Developments in MRI and PET have brought more attention to prostate imaging and the possibility of improving the accuracy of focal therapy. In this Review, we discuss the advantages and disadvantages of conventional methods for imaging the prostate, new developments for targeted imaging, and the possible role of image-guided biopsy and therapy for localized prostate cancer.