[1] Stanford Univ, Sch Med, Dept Radiol, Palo Alto, CA USA
[2] Stanford Univ, Sch Med, BioX Program, Palo Alto, CA USA
[3] Univ Calif Los Angeles, David Geffen Sch Med, Crump Inst Mol Imaging, Los Angeles, CA USA
[4] Univ Calif Los Angeles, David Geffen Sch Med, Dept Mol & Med Pharmacol, Los Angeles, CA USA
[5] Med Coll Wisconsin, Dept Radiol, Milwaukee, WI 53226 USA
[6] Univ Cambridge, Sch Clin Med, Dept Radiol, Cambridge, England
[7] Univ Cambridge, Sch Clin Med, Dept Oncol, Cambridge, England