[1] Seoul Natl Univ, Coll Med, Dept Prevent Med, Seoul, South Korea
[2] Seoul Natl Univ, Coll Med, Dept Biomed Sci, Seoul, South Korea
[3] Seoul Natl Univ, Med Res Ctr, Inst Environm Med, Seoul, South Korea
[4] Seoul Natl Univ, Coll Med, Canc Res Inst, Seoul, South Korea
[5] NCI, Div Canc Epidemiol & Genet, Rockville, MD USA
[6] Seoul Natl Univ, Coll Med, Dept Surg, Seoul, South Korea
[7] Seoul Natl Univ, Bundang Hosp, Dept Surg, Songnam, South Korea
[8] Seoul Natl Univ, Coll Med, Dept Internal Med, Seoul 151, South Korea
[9] Seoul Natl Univ, Coll Med, Liver Res Inst, Seoul, South Korea