MRinRT: Swansea University and SWWCC Collaboration Study.

The aim of this study is to learn whether using MRI (magnetic resonance imaging) scans to plan radiotherapy is better than using CT (computed tomography) scans alone. The main questions it aims to answer is:

* Can MRI scan images be adjusted to make the tumour and normal tissues easier to see? * Does adding MRI to a radiotherapy planning CT make the radiotherapy plan more precise? * Can MRI be used to adjust a radiotherapy plan during a course of treatment to make it more precise, and might that reduce the side effects? * Are there particular MRI scans that can predict how a tumour will respond to radiotherapy or how likely the patient is to have side effects?

This study will assess current MRI scanning procedures and ensure these are adjusted to best suit radiotherapy planning. It will also provide pilot data evaluating:

1. MRI-adapted radiotherapy Usually, radiotherapy plans are based on a pre-treatment planning CT scan. Unless an issue is detected the patient would complete their whole course of radiotherapy on this plan. This does not account for changes in position/size/shape of the tumour that occur over the whole treatment course. Clinicians therefore increase the size of the tumour/target to account for these uncertainties, which can increase side effects. This study will assess the potential to reduce side effects from radiotherapy by using repeat MRI scans and replanning during the treatment course (MRI-adaptive radiotherapy). 2. Imaging biomarkers MRI sequences can be used to predict response to radiotherapy or chance of developing side effects. This study will identify potential MRI sequences that may be used as imaging biomarkers, to guide the development of future clinical trials.

The study will be undertaken at SBUHB, lasting 4 years, and involving ≤15 healthy volunteers and ≤150 patients.