1. 1Department of Epidemiology and Biostatistics, Temple University, College of Public Health, Temple Fox Chase Cancer Center, Philadelphia, Pennsylvania.
2. 2Department of Biology, Lincoln University of Pennsylvania, Lincoln, Pennsylvania.
3. 3Department of Neurosurgery, Duke University, School of Medicine, Durham, North Carolina.
4. 4Department of Population and Quantitative Health Sciences, Case Western Reserve University, School of Medicine, School of Medicine, Cleveland, Ohio.
5. 5Penn State Cancer Institute, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania.
6. 6Ipsen Bioscience, Cambridge, Massachusetts.
7. 7Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, Maryland.