Therapy assessment of bone metastatic disease in the era of 223radium.

PURPOSE Defining an optimal imaging modality for assessment of therapy and the best time of evaluation are pivotal for ideal patient's management. METHODS Ra (Xofigo®, formerly Alpharadin) has been approved by the FDA and European Medicines Agency for treatment of metastatic castration-resistant prostate cancer with painful osseous involvement. RESULTS PET/CT imaging using various radiotracers such as F-FDG, F-FCH, Ga-PSMA and F-NaF have been investigated to mitigate the limitations of conventional imaging modalities. Diagnostic radiotracers that have properties similar to a therapeutic radiotracer will precisely assess of the possibility and efficacy of a treatment; this is the theranostic concept. An example of a diagnostic test employed for selecting targeted therapy is the combined use of F-fluoride PET/CT for evaluation of possible therapy with Ra. CONCLUSION This review examines the most recent publications related to this topic.