Descriptive analysis of MRI functional changes occurring during reduced dose radiotherapy for myxoid liposarcomas

British Journal of Radiology, vol. 94, pp. 20210310

Abstract

OBJECTIVES: Myxoid liposarcomas (MLS) show enhanced response to radiotherapy due to their distinctive vascular pattern and therefore could be effectively treated with lower radiation doses. This is a descriptive study to explore the use of functional MRI to identify response in a uniform cohort of MLS patients treated with reduced dose radiotherapy. METHODS: 10 patients with MLS were imaged pre-, during, and post-radiotherapy receiving reduced dose radiotherapy and the response to treatment was histopathologically assessed post-radiotherapy. Apparent diffusion coefficient (ADC), T2* relaxation time, volume transfer constant (Ktrans), initial area under the gadolinium curve over 60 s (IAUGC60) and (Gd) were estimated for a central tumour volume. RESULTS: All parameters showed large inter- and intrasubject variabilities. Pre-treatment (Gd), IAUGC60 and Ktrans were significantly different between responders and non-responders. Post-radiotherapy reductions from baseline were demonstrated for T2*, (Gd), IAUGC60 and Ktrans for responders. No statistically significant ADC differences were demonstrated between the two response groups. Significantly greater early tumour volume reductions were observed for responders. CONCLUSIONS: MLS are heterogenous lesions, characterised by a slow gradual contrast-agent uptake. Pre-treatment vascular parameters, early changes to tumour volume, vascular parameters and T2* have potential in identifying response to treatment. The delayed (Gd) is a suitable descriptive parameter, relying simply on T1 measurements. Volume changes precede changes in MLS functionality and could be used to identify early response. ADVANCES IN KNOWLEDGE: MLS are are characterised by slow gradual contrast-agent uptake. Measurement of the delayed contrast-agent uptake (Gd) is simple to implement and able to discriminate response.

Authors 15

1. Evanthia Kousi

   Royal Marsden NHS Foundation Trust · Institute of Cancer Research

   Affiliation as printed

   MRI unit, The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research , London , UK

2. Christina Messiou

   Royal Marsden NHS Foundation Trust · Royal Marsden Hospital

   Affiliation as printed

   Radiology department, The Royal Marsden NHS Foundation Trust , London , UK

3. Aisha B Miah

   Royal Marsden NHS Foundation Trust

   Affiliation as printed

   Sarcoma Unit, The Royal Marsden NHS Foundation Trust , London , UK

4. Matthew R. Orton

   Royal Marsden NHS Foundation Trust · Institute of Cancer Research

   Affiliation as printed

   MRI unit, The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research , London , UK

5. Rick L. Haas Aachen Department of Radiotherapy, Leiden University Medical Center

   Leiden University Medical Center · The Netherlands Cancer Institute

   Affiliation as printed

   Department of Radiotherapy, Leiden University Medical Center , Leiden , The Netherlands

   Sarcoma Unit, Department of Radiotherapy, The Netherlands Cancer Institute , Amsterdam , The Netherlands

6. Khin Thway

   Royal Marsden NHS Foundation Trust

   Affiliation as printed

   Molecular pathology, The Royal Marsden NHS Foundation Trust , London , UK

7. Georgina Hopkinson

   Royal Marsden NHS Foundation Trust · Institute of Cancer Research

   Affiliation as printed

   MRI unit, The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research , London , UK

8. Shane Zaidi

   Royal Marsden NHS Foundation Trust

   Affiliation as printed

   Sarcoma Unit, The Royal Marsden NHS Foundation Trust , London , UK

9. Myles Smith

   Royal Marsden NHS Foundation Trust

   Affiliation as printed

   Sarcoma Unit, The Royal Marsden NHS Foundation Trust , London , UK

10. Elizabeth Barquin

    Royal Marsden NHS Foundation Trust

    Affiliation as printed

    Sarcoma Unit, The Royal Marsden NHS Foundation Trust , London , UK

11. Eleanor C. Moskovic

    Royal Marsden NHS Foundation Trust · Royal Marsden Hospital

    Affiliation as printed

    Radiology department, The Royal Marsden NHS Foundation Trust , London , UK

12. Nicos Fotiadis

    Royal Marsden NHS Foundation Trust · Royal Marsden Hospital

    Affiliation as printed

    Department of Interventional Radiology, The Royal Marsden NHS Foundation trust , London , UK

13. D. Strauß

    Royal Marsden NHS Foundation Trust

    Affiliation as printed

    Sarcoma/Melanoma Unit, The Royal Marsden NHS Foundation Trust , London , UK

14. Andrew J Hayes

    Royal Marsden NHS Foundation Trust

    Affiliation as printed

    Sarcoma/Melanoma Unit, The Royal Marsden NHS Foundation Trust , London , UK

15. Maria Angélica Schmidt

    Royal Marsden NHS Foundation Trust · Institute of Cancer Research

    Affiliation as printed

    MRI unit, The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research , London , UK