[1] Johns Hopkins Univ, Sch Med, Baltimore, MD 21205 USA
[2] Johns Hopkins Univ, Bloomberg Sch Publ Hlth, Dept Epidemiol, Baltimore, MD 21205 USA
[3] Johns Hopkins Univ, Bloomberg Sch Publ Hlth, Dept Mol Microbiol & Immunol, Baltimore, MD 21205 USA
[4] Chinese Acad Med Sci, Dept Epidemiol, Canc Inst Hosp, Beijing 100730, Peoples R China
[5] Global Canc Initiat, Chestertown, MD USA