[1] Natl Canc Ctr, Radiat Med Branch, Inst Res, Ilsan Gu, Goyang Si 411764, Gyeonggi Do, South Korea
[2] Natl Canc Ctr Hosp, Natl Canc Ctr, Ctr Liver Canc, Gyeonggi Do 411764, South Korea
[3] Univ Ulsan, Coll Med, Dept Diagnost Radiol, Asan Med Ctr,Songpa Gu, Seoul 138736, South Korea
[4] Sungkyunkwan Univ, Sch Med, Dept Radiol, Samsung Med Ctr,Kangnam Gu, Seoul 135710, South Korea
[5] Sungkyunkwan Univ, Sch Med, Dept Radiol, Gastrointestinal Ctr,Kangnam Gu, Seoul 135710, South Korea