New developments in treatment planning and verification of particle beam therapy.

Charged particle beam therapy has been used for almost 60 years. During the initial 40 years, the medical use of protons and heavy ions was explored at accelerator laboratories in a limited number of patients and for a limited number of cancerous and non-cancerous disease conditions. After the development of computed tomography and 3D treatment planning, it was time to move charged particle therapy into the clinical realm. This happened in October 1991 when an ocular melanoma patient became the first patient to be treated at Loma Linda University Medical Center in California. Due to the increased awareness of the advantages of charged particle therapy and promising results of single-institution experiences, one currently observes a phase of rapid expansion of proton treatment centers throughout the world. A few of these centers are combined proton/carbon ion facilities. It is very important that the technological evolution of charged particle therapy will continue during this phase of clinical expansion to ensure that the increasing number of patients exposed to therapeutic charged particles will benefit most from the advantageous dose distributions that these particles afford. This report will give an overview of translational research activities related to planning and verification of proton therapy in which the authors have been involved for a number of years. While our activities focus on protons, these developments are to a large degree also applicable to carbon ion therapy.