Ellen Ackerstaff1, Mihai Coman1, Sean Carlin1, Sean A. Burke1, Kristen L. Zakian1, Khushali Kotedia1, Joseph O'Donoghue1, Clifton C. Ling1, Jason A. Koutcher1
1Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
Tumor hypoxia has been related to treatment response. We used in vivo 19F-MRS/MRSI of Trifluoromisonidazole (TF-MISO) to evaluate tumor hypoxia in two animal tumor models. Intratumoral TF-MISO concentrations were only moderately influenced by tumor growth in both tumor models. The breathing of 21%O2, 95%O2/5%CO2, or 100%O2 did not significantly influence intratumoral TF-MISO levels in the MCa tumor, whereas in R3327-AT tumors, breathing of 100%O2 decreased significantly intratumoral TF-MISO levels in tumors below ~600mm3. Our results suggest that hypoxia imaging by 19F MR of TF-MISO may help to identify tumors that can be successfully reoxygenated and, thus, sensitized for radiation therapy.