Abstract
OBJECTIVE: A theranostic system integrates some form of diagnostic testing to determine the presence of a molecular target for which a specific drug is intended. Molecular imaging serves this diagnostic function and provides powerful means for noninvasively detecting disease. We briefly review the paradigms rooted in nuclear medicine and highlight recent advances in this field. We also explore how nanometer-sized complexes, called nanomedicines, present an excellent theranostic platform applicable to both drug discovery and clinical use. CONCLUSION: For imagers, molecular theranostics represents a powerful emerging platform that intimately couples targeted therapeatic entities with noninvasive imaging that yields information on the presence of defined molecular targets before, during, and after cognate therapy.