Abstract
Aim: Summary of the development of therapy using radionuclides and potential of alpha radionuclides in targeted therapy. Introduction: The interest aimed on radionuclides emitting alpha particles is constantly growing in nuclear medicine.
In the case of targeted alpha therapy, not only radionuclides decaying by one or several alphas are used, but also the suitable carriers for these radionuclides are developed and could be used as radiopharmaceuticals. Material: Since 1908, less than ten years after its discovery, radium had been used in medicine mainly to treat skin diseases.
Since then therapy using radionuclides has gone a long way - from radium-226, through electron emitters, 211At, to nuclides forming short-lived decay chains known as in vivo generators, e.g. 225Ac, 213Bi or 223Ra. The advantage of alpha therapy is the release of a high energy in a small volume, which leads to lower radiation exposure of surrounding tissues.
Due to the high LET of alpha particles, double-strand breaks of DNA molecules, which are lethal for the cell, are formed. For this reason, the carriers of alpha radionuclides should resist to the high released energy, in order to prevent its radiolysis.
The stabilisation of reflected daughter nuclide is also important because of its release into surrounding tissue and thus its damage. Among studied carriers of alpha radionuclides inorganic nanomaterials dominate, e.g. iron, titanium or gold oxide nanoparticles or hydroxyapatite.
Conclusions: The research in the field of targeted alpha therapy opens the way to treatment of some types of cancerous diseases and especially the increase of patients' life quality and its extension. Therefore, the effort to prepare new radionuclides should continue, suitable both for early diagnosis and subsequent therapy.
Particular attention should also be given to the therapeutic radionuclide carriers, best suited to the theranostic concept, with regard to their chemical and radiation stability and availability.