An ICRU report on Prescribing, Recording and Reporting Light Ion Beam Therapy has been submitted to the Journal of the ICRU by end of 2018. This report is the result of a longstanding collaboration between the IAEA and ICRU and has been initiated after joint meetings in Vienna, Austria (2004) and Columbus, Ohio (2006) in an attempt to standardize the reporting of light ion beam radiotherapy. It relies on concepts previously developed by the ICRU for reporting other therapies but with special emphasis on the use and reporting of RBE-weighted quantities. Such harmonization will facilitate the comparison of therapeutic results obtained with ions not only between ion beam therapy centers but also with centers using other modern forms of radiation therapy, such as proton-RT and IMRT with photon beams. 
The report outlines the different biological models used for calculating RBE weighted dose for light ion beam therapy and attempts to clarify their clinical use in order to enable a common understanding of clinical practice in various facilities. It gives detailed recommendations on how light ion beam therapy should be prescribed, recorded and reported. The physical and technical background of light ion beam therapy is explained. The recommendations on dosimetry were harmonized and updated according to ICRU report 90 (Key Data for Ionizing-Radiation Dosimetry: Measurement Standards and Applications, 2016) and with the upcoming revision of IAEA’s TRS-398 (Absorbed Dose Determination in External Beam Radiotherapy: An International Code of Practice for Dosimetry based on Standards of Absorbed Dose to Water, 2016).

04 - The new ICRU report on Prescribing, Recording and Reporting Light Ion Beam Therapy