Development of Analytical Transport Methods for Biologically Optimized Light Ion Therapy

A general objective in the treatment of cancer is to eradicate the tumour cells without inducing severe complications in healthy normal tissue. The use of light ions for radiation therapy increases the possibility to deliver tumour suicidal doses almost without normal tissue injury, not least in cases where the target is unresectable, radio resistant and located near organs at risk. The success in the application of such beams in radiation therapy is largely determined by a thorough understanding of particle transport, biological dose response functions and their accurate integration in the treatment planning system. The focus has therefore been on the radiation quality of the light ions, their transport and to develop analytical tools and theories for their application in biological optimized radiation treatment planning. New analytical approaches for the light ion transport in matter have been developed and new range concepts have been identified. A refined version of the Monte Code SHIELD-HIT was developed and used for calculating fundamental physical transport quantities that could be directly compared with the analytical theories and methods as well as with experimental data. The present results are useful for biological optimized treatment planning, biologically optimized dose delivery techniques, dosimetry and for in vivo dose delivery verification.