Vickie Yi Zhang1, Robert Bok1, Subramaniam Sukumar1, Adam Cunha2, I-Chow Hsu2, Kristen Scott1, Jean Pouliot2, Daniel Vigneron1, John Kurhanewicz1
1Dept. of Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States; 2Dept. of Radiation Oncology, University of California, San Francisco, San Francisco, CA, United States
This study investigated serial changes in hyperpolarized (HP) pyruvate metabolism and perfusion (via HP urea) in TRAMP prostate tumors following exposure to varying doses (14-5Gy) of radiation therapy to better understand the potential clinical value of HP13C MR for monitoring prostate cancer radiation therapy. Significant, dose-dependent changes in perfusion and HP lactate-to-pyruvate (lac/pyr) flux were observed early (1-8 days) after radiation therapy. HP urea significantly decreased within high (14-12Gy) and intermediate (12-7Gy) dose regions of radiation, but initially increased before decreasing in low (5-7Gy) dose regions. For all three dose regions, lac/pyr ratios significantly decreased by 8 days following treatment.