[1] Seoul Natl Univ Hosp, Dept Internal Med, Seoul 03080, South Korea
[2] Seoul Natl Univ, Coll Med, Canc Res Inst, Seoul, South Korea
[3] Seoul Natl Univ Hosp, Biomed Res Inst, Ctr Med Innovat, Seoul, South Korea
[4] Seoul Natl Univ Hosp, Ctr Palliat Care & Clin Eth, 101 Daehak Ro, Seoul 03080, South Korea
[5] Seoul Natl Univ Hosp, Biomed Res Inst, Ctr Med Innovat, 101 Daehak Ro, Seoul 03080, South Korea