Manchester BRC researchers publish research into the use of new technology (MR-Linac)
Two papers recently published by Manchester researchers will help shape guidance for targeting tumours more accurately using the new MR-Linac, which combines MRI scanning and radiotherapy in one hi-tech package.
Current radiotherapy is already personalised and adaptive to some degree, as treatment is based on the size and shape of the individual and the tumour, as well as the location of the tumour. Depending on the location of the tumour, patients are scanned during the radiotherapy and the treatment adjusted accordingly.
The MR-linac offers the potential to revolutionise treatment – reducing the radiotherapy dose to surrounding organs, reducing side-effects and improving quality-of-life. It will enable clinicians to provide an adaptive radiotherapy plan fine-tuned to the daily changes in the anatomy of the patient, by imaging at the same time as delivering each dose or ‘fraction’ of radiotherapy. However, combining MRI with radiotherapy is a major challenge for physicists because the radiation treatment is affected by the MR scanner’s strong magnetic field.
Research published in the journal Clinical Oncology1 by the MR-Linac team in Manchester, who are part of an international Consortium of 7 centres, describes the benefits and challenges of integrating the new technology into standard practice. The research supported by Elekta Ltd also sets out guidance and progress to date, for example, the adaptation of treatment plans and identification that challenges exist around imaging some body sites using MRI which must be overcome to enable effective use of the MR-Linac.
Manchester researchers have also co-authored a paper published in the journal, Medical Physics2. This research supported by a Cancer Research UK Network Accelerator Award to the Advanced Radiotherapy Technologies Network explores the identification of patients who could benefit from treatment on the MR-Linac. The MR-Linac has a maximum radiation field size (size of treatment area) which may impact on the types of patients who can benefit from the technology. Based on field size, the researchers discovered that 80% of all treatment plans could be delivered successfully using the MR-Linac. This increases to 100% for smaller tumours, such as prostate and brain, but is less for larger tumours, for example, cervix (61%) and head and neck (66%).
Through its Advanced Radiotherapy research, the NIHR Manchester Biomedical Research Centre is embracing technological advances and developing biomarkers to predict the effectiveness of different types of radiotherapy and drug-radiotherapy combinations, as well as helping to minimise the risk of long-term side effects.
References
1. A Choudhury, G Budgell, R Mackay, et al (2017). The Future of Image-guided Radiotherapy. Clinical Oncology 29: 662–666 (https://authors.elsevier.com/a/1VgUz3K~8ROhtS)
2. R Chuter, P Whitehurst, A Choudhury, et al (2017). Technical Note: Investigating the impact of field size on patient selection for the 1.5T MR-Linac (http://onlinelibrary.wiley.com/doi/10.1002/mp.12557/abstract)