ABSTRACT

Theranostics is described as the association of therapy agent with diagnostic method which predicts the effect of the therapeutic agent. It is created by joining the words ‘therapy’ and ‘diagnostics/diagnosis’. This approach enables to predict the therapy outcome by merging the diagnostic method with the therapy, since, the molecular imaging or diagnostic tests are performed with a diagnostic agent which is in the same or similar structure with the therapeutic agent. This method may particularly be used in personalized medicine applications. Many diagnostic or therapeutic procedures in nuclear medicine are a part of theranostics. Iodine I-131 therapy/scintigraphy is a very prominent example of theranostics. The relation of the diagnostic test with the therapeutic procedure can be classified in three groups: the diagnostic and therapeutic molecules are the same, the diagnostic and therapeutic molecules are similar, and the diagnostic and therapeutic molecules are different, but the localization process is the same. Consequently, the agent which shows the therapeutic effect is administered to those patients with the positive diagnostic test, mostly ensuring the success of the therapy. Nanoparticles that simultaneously carry out diagnostic imaging and drug release are also a rapidly developing issue in theranostics. Diagnostic and therapeutic agents showing flourescent, ultrasonic, magnetic, radioactive, contrast, pharmacological drug or antibody characteristics are loaded on the nanoparticles resulting in theranostic use. Developing specific diagnostic tests and targeted therapy methods will also be beneficial to reduce the medical costs.