FLT PET/MR for Evaluation of Pseudoprogression in Patients With Brain Lesions

Identifying imaging biomarkers of metastatic brain tumor treatment response could allow early modification of treatment by determination of tumor progression vs. treatment related effects (pseudo-progression, radiation necrosis). Earlier treatment response assessment could reduce cost, improve clinical trial efficiency and allow better assessment of prognosis. The development of PET/MRI offers the possibility of combining the functional imaging of PET with the exquisite soft tissue contrast and physiologic imaging capabilities of MRI. Combining FLT-PET imaging with MRI may allow better evaluation of new and unclear lesions in brain metastatic disease. The goal of this study is to explore FLT-PET imaging combined with dynamic MR imaging techniques for the identification of tumor response markers in metastatic brain tumors.