Hadron therapy in radiation oncology and why BNCT is a paradigm shift

Abstract Purpose Hadrons, i.e. particles that are heavier than electrons, are playing an increasingly important role in radiation oncology. Due to the high investment costs for the necessary infrastructure, this option is only available in specialized centers. Methods This article describes some of the physical properties that make hadrons attractive for external beam radiation therapy (EBRT), but also some of the challenges that need to be considered. Results The importance of linear energy transfer for biological effects is discussed. Conclusions In addition to the use of charged particles, the importance of neutrons for radiotherapy is also highlighted, in particular the properties of boron neutron capture therapy (BNCT), which open up completely new possibilities for the further development of EBRT.