Trial Information

Whole Body Diffusion-weighted MRI (WB-DWI) for Early Prediction and Evaluation of Therapy Response in Patients With Advanced Metastatic Gastrointestinal Stromal Tumors (GIST) Treated With Regorafenib.

Aim of the study

- To assess whole body diffusion-weighted magnetic resonance imaging (WB-DWI) for the
assessment and early prediction of response of treatment with regorafenib or placebo in
patients with advanced, metastatic gastro-intestinal stromal tumors (GIST)

1. Evaluation of pretreatment apparent diffusion coefficient (ADC) and b1000 signal
intensity (SI) of GIST visualized on the WB-DWI as predictor of time to progression,
determined by progression-free survival (PFS)

2. Evaluation of WB-DWI using changes of high b-value SI and ADC early during treatment
(2weeks after start of therapy; allowed optimal window 10-14 days) as early predictor
of time to progression or patient benefit according to RECIST (stable disease +
partial response + complete response)

3. Evaluation of WB-DWI for treatment follow-up 3 months after initiation of treatment.
Confirmation of prior published pilot study (Dunet V et al, J Nucl Med 2010)

4. Comparison of WB-DWI with conventional CT imaging for response assessment