[1] University School of Medicine,Division of Oncology, Lombardi Comprehensive Cancer Center, Georgetown
[2] National Institutes of Health,Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics
[3] National Cancer Institute,Department of Medicine, Division of Oncology
[4] The University of Texas Health Science Center School of Public Health,undefined
[5] The University of Texas Health Science Center at Houston,undefined
[6] McGovern Medical School,undefined