1 Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin; Radiation Oncology Associates-New England, Manchester, New Hampshire. Electronic address: jvbrower@wisc.edu.
2 Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.
3 Department of Radiation Oncology, Hospital of the University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania.