1 Department of Radiation Oncology, Duke University Medical Center, Durham, USA; Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, USA. Electronic address: david.kirsch@duke.edu.
2 Department of Radiation Oncology, Stanford University, Stanford, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Stanford, USA; Stanford Cancer Institute, Stanford University, Stanford, USA.
3 Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, USA.
4 Department of Radiation and Cellular Oncology, The University of Chicago, USA.