The public defence will be held as a video conference over Zoom.
The defence will follow regular procedure as far as possible, hence it will be open to the public and the audience can ask ex auditorio questions when invited to do so.
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Digital Trial Lecture - time and place
Adjudication committee
- First opponent: Professor Isabella Björkman-Burtscher, Sahlgrenska Academy, University of Gothenburg, Sweden
- Second opponent: Associate Professor Erik Magnus Berntsen, Norwegian University of Science and Technology, Trondheim, Norway
- Third member and chair of the evaluation committee: Professor Angelika Sorteberg, Institute for Clinical Medicine, University of Oslo, Norway
Chair of defence
Professor Hanne Flinstad Harbo, Institute of Clinical Medicine, University of Oslo
Principal Supervisor
Andrés Server Alonso, Oslo University Hospital
Summary
Diffuse infiltrative gliomas are the most common primary brain tumors in adult population and represent a range from slow-growing lesions to highly invasive tumors with poor prognosis. The standard radiographic characterization of glioma is based on magnetic resonance imaging (MRI); a widely utilized examination for both initial diagnosis and for ongoing post-treatment management of these patients.
The objectives of this thesis were to evaluate the value of the advanced MRI techniques, as perfusion and diffusion imaging, to characterize diffuse gliomas with respect to WHO grade, morphologic and genetic features, but also to find new imaging prognostic biomarkers in order to individualize medical management.
We found that patients with oligodendrogliomas showed significantly higher microvascularity and higher vascular heterogeneity than patients with astrocytomas. Combined use of ADC and rCBV histogram parameters had superior diagnostic performance to identify oligodendroglial tumors.
In patients with oligodendrogliomas, we found that tumors with heterogeneous perfusion signatures and high average perfusion values were associated with longer progression-free survival (PFS), while in patients with diffuse astrocytomas, heterogeneous perfusion distribution was associated with poorer outcomes.
Shorter survival outcomes in patients with glioblastomas were significantly associated with higher RSI-cellularity index in the contrast-enhanced zone, but also in peri-tumoral zone.
In conclusion, our results suggest that both perfusion and diffusion MRI provide reliable non-invasive biomarkers of glioma status and the information from the two imaging techniques appear to be complementary. To further implementation of these modalities in a diagnostic workflow, multicenter studies are warranted that would assist in standardizing imaging protocols as well as post-processing procedures.
Additional information
contact the Research Support staff