Abstract #0757

Comparison of Diffusion Weighted Imaging with [18F]-FLT Uptake in a Human Colon Cancer Xenograft Model using Treatment Strategies

Valerie Simone Honndorf¹, Sally-Ann Ricketts², Jane Halliday², Hans F. Wehrl³, Stefan Wiehr³, Damaris Kukuk³, Maren K. Koenig³, Mareike Lehnhoff³, Julia Mannheim³, Gerald Reischl⁴, Bernd J. Pichler³

¹Laboratory for Preclinical Imaging and Imaging Technology of the Werner Siemens-Foundation , University of Tuebingen, Tuebingen, Germany; ²Imaging, Translational Sciences, AstraZeneca, Alderley Park, Macclesfield, Cheshire, United Kingdom; ³Laboratory for Preclinical Imaging & Imaging Technology of the Werner Siemens-Foundation, University of Tuebingen, Tuebingen, Germany; ⁴Radiopharmacy & PET-Center, University of Tuebingen, Tuebingen, Germany

Diffusion-weighted MRI in combination with PET is a powerful tool to monitor cancer therapy. We show the correlation between the [¹⁸F]FLT-PET imaging and the apparent diffusion coefficient (ADC) in a colon cancer mouse model in a control group and a group treated with docetaxel. We found that the ADC maps reveal an inverse spatial correlation to the [¹⁸F]FLT uptake in the tumor demonstrating the relationship between water diffusion in necrotic regions and the thymidine kinase activity in proliferating cells. Such complementarities between MR diffusivity and [¹⁸F]FLT-PET open new insights for the usability of diffusion-weighted imaging as diagnostic tool in oncology.