Molecular Surgery with Auger Electron-Emitting Radiopharmaceuticals

The intense focus of radiochemical damage and cytotoxicity induced by Auger electron emitters is well known and provides a basis for their potential use in cancer therapy. Auger electron-emitting radionuclides decay by electron capture and/or internal conversion. The key feature of these modes of decay is the simultaneous release of low energy electrons, collectively known as Auger electrons. The unique characteristic of the majority of these electrons is their ultra short-range - they traverse only molecular dimensions - in biological tissue, resulting in a highly localized energy deposition in the immediate site of the decaying radionuclide. Therefore, Auger emitters have the potential to provide exquisite cell specificity in targeted cancer radiotherapy applications. However, their very limited effective range implies that there is a requirement to deliver these radionuclides to the DNA of target cells, to realize their maximum potential in cancer therapy. The radiobiological properties and therapeutic potential of Auger emitters has been the subject of intense exploration by a small but dedicated group of researchers for the past four decades. In this article we focus on recent advances relating to targeted cancer therapy with Auger electron-emitting radionuclides. State-of-the-art technologies for potential DNA-targeted cancer radiotherapy with Auger emitters are also presented.