7. Prescribing, Recording, and Reporting

• Level 1 recommendations are the minimum standards for prescribing and reporting. Below these standards radiotherapy should not be performed and these standards apply for simple treatments such as 2D planned treatments. • Level 2 recommendations apply for the prescribing and reporting state-of-the-art techniques using computational dosimetry and 3D imaging. Treating at Level 2, all volumes of interest [e.g., gross tumor volume (GTV), clinical target volume (CTV), planning target volume (PTV), organs at risk (OARs), and planning organ-at-risk volume (PRV) (Section 3)] are delineated and 3D absorbed-dose distributions are available and they include heterogeneity corrections (Section 4). Dose–volume histograms (DVHs) for all volumes of interest are computed. A complete QA program is used to ensure that the prescribed treatment is accurately delivered (Section 6). • Level 3 recommendations are recommendations for optional reporting of research and novel developments. They are used for the development of new techniques and/or approaches for which reporting criteria are not yet standardized by the ICRU (ICRU, 2010).