Janine Ring1, Stefanie Remmele2, Walter Heindel1, Thorsten Persigehl1, Christoph Bremer1
1Department of Clinical Radiology, University Hospital of Muenster, Muenster, Germany; 2Medical Imaging Systems, Philips Research Europe, Hamburg, Germany
Sensitive tools for early monitoring of anti-angiogenic tumor treatment are desired. Therefore, tumor bearing nude mice were treated with a multi-targeted tyrosine kinase inhibitor and investigated by USPIO enhanced steady state MRI and diffusion weighed imaging (DWI) before and after treatment. In response to therapy, the decrease in R2*- and vessel size maps clearly visualized the decrease in blood supply and the ADC-maps showed a water diffusion increase, reflecting the reduced tumor tissue cellularity. Histological analysis confirmed the MR-results, underlining that multi-parametric MR imaging allows for anti-angiogenic tumor treatment monitoring by non-invasive visualization of tumor microvascular and cellularity changes.