Magnetic Resonance Imaging Biomarkers for assessment of early treatment response in radiotherapy
Cancer is to a large extent treated with radiotherapy, which is delivered to the patients in several fractions. The treatment can extend over several weeks. There is a great need for imaging methods, especially MRI, that can assess the treatment response during the treatment. With the right knowledge of the response in the tumour, the treatment can be adapted. The radiation dose can be increased if the response is low, or the dose can be reduced if the response is high. In the latter case a reduction of the dose can result in less side effects. MRI as an imaging technique has the advantage of providing functional read-outs (DWI, DCE, DSC etc) and thereby be more sensitive to changes in the tumour, than otherwise is possible. In many oncology centers there is a dedicated MR-scanner that can provide these measurements at different occasions during the treatment. The new modality MR-linac, which is a combination of a treatment machine and MR-scanner, further provides the possibility to make day-to-day adaptations. In this session the new concept of using MR imaging biomarkers for radiotherapy is explained, applications are described and future possibilities discussed.
| Session duration: | 60m |
| Intended audience: | Physicists, Radiologists, Oncologists |
| Moderators: | Lars E. Olsson, Petra van Houdt (Confirmed: Lars E. Olsson, Petra van Houdt) |
| First Speaker: | Faisal Mahmood (Confirmed: Faisal Mahmood) |
| Second Speaker: | Tord Hompland (Confirmed: Tord Hompland) |
Session description
Background
Cancer is to a large extent treated with radiotherapy, which is delivered to the patients in several fractions. The treatment can extend over several weeks. There is a great need for imaging methods, especially MRI, that can assess the treatment response during the treatment. MRI methods are widely developed and used in diagnostic radiology. There is a huge need to increase the MRI, especially quantitative functional methods in the radiotherapy arena. A challenge and opportunity for the MRI community. With the right knowledge of the response in the tumour, the treatment can be adapted. The radiation dose can be increased if the response is low, or the dose may be reduced without compromising the response. In the latter case a reduction of the dose can result in less side effects. MRI as an imaging technique has the advantage of providing functional read-outs (DWI, DCE, DSC etc) and thereby be more sensitive to changes in the tumour than otherwise is possible. In many oncology centers there is a dedicated MR-scanner that can provide these measurements at different occasions during the treatment. The new modality MR-linac, which is a combination of a treatment machine and MR-scanner, further provides the possibility to make day-to-day adaptations. In this session the concept of using MR imaging biomarkers for radiotherapy is explained, state of the art applications are described and future possibilities discussed. MRI
Organizer and chair Lars E. Olsson, Lund University, Lund, Sweden Co-chair Petra van Houdt, NKI Amsterdam NL
1. MR-imaging biomarkers of early response – introduction
In this short introduction the concept of imaging biomarkers and the roadmap from discovery to clinical applications are described. Furthermore, the necessity of imaging biomarkers to guide radiotherapy is explained. 10 min – speaker Petra van Houdt, NKI Amsterdam NL
2. Diffusion MRI as a measure of tumour response to radiotherapy
Diffusion MRI is the method that has proven the most potential to characterize tumours before and during therapy. In this talk different diffusion MRI methods, from simple ADC to advanced diffusion methods (kurtosis, multidimensional, time dependent) are discussed for assessment of radiotherapy response. Examples from clinical trials in various organs will be reviewed. 20 min – speaker Faisal Mahmood, Syddansk Universitet, Odense, Denmark
3. A novel non-invasive MRI imaging method to assess tumour hypoxia – from validation to clinical applications
A recently presented method that has gained lot of interest lately, to non-invasively assess hypoxia maps in tumours using diffusion MRI will be presented. The method does not require sophisticated or state-of-the-art imaging gradients, is relatively rapid, can be repeated at any relevant time point and requires no exogenous contrast media. The validation of the method against gold standard will be described. Recent application in clinical trials reviewed. The pros, cons and limitations will be discussed. 20 min – speaker Tord Hompland, The Norwegian Radium Hospital, Oslo, Norge
4. Discussion and summary
10 min