Radiotherapy is increasingly moving towards MR-guided and adaptive procedures. Lagendijk et al. (Nature Reviews Clinical Oncology, 2014) demonstrate the importance of integrating imaging and therapy.
In future, materials will need to be both dosimetrically precise and highly compatible with imaging modalities such as CT or MRI. Artifact formation or unclear density values can complicate treatment planning and verification and lead to uncertainties in dose calculation. This property becomes especially important in the context of adaptive radiotherapy, where imaging and treatment are becoming ever more closely interlinked. Bolus materials should therefore offer stable, reproducible physical properties throughout the entire course of treatment. At the same time, aspects such as hygiene, reusability and patient-friendly application are coming increasingly into focus. Looking ahead to the future of radiotherapy, it is clear that materials must not only be functional but also integrate seamlessly into digital, image-guided workflows.