The RCR recommends, at a minimum, that the following records are retained until eight years after death:

• Planning CT information in DICOM image format
• Patient-specific photos and diagrams
• Patient-specific measurements
• Radiation dose and fractionation: both that prescribed and delivered
• Plan construction information -- for example, field size, monitor units, etc.
• 3D dose distribution information; dose/volume histogram information and dose to organs at risk
• Independent dose/monitor unit verification
• Imaging obtained during treatment verification
• Systemic anticancer therapy delivered -- including drug name, dose prescribed and delivered, toxicities experienced, and supporting medications delivered

Further details are available on the RCR website.