[1] Hanyang Univ, Coll Med, Dept Gastroenterol & Hepatol, Guri, South Korea
[2] Univ Ulsan, Asan Med Ctr, Dept Oncol, Coll Med, Seoul, South Korea
[3] Univ Ulsan, Asan Med Ctr, Dept Biostat & Clin Epidemiol, Coll Med, Seoul, South Korea
[4] Kyung Hee Univ Hosp Gangdong, Dept Gastroenterol, Seoul, South Korea
[5] Univ Ulsan, Asan Med Ctr, Dept Surg, Coll Med, Seoul, South Korea
[6] Univ Ulsan, Asan Liver Ctr, Asan Med Ctr, Coll Med, Seoul, South Korea
[7] Univ Ulsan, Asan Med Ctr, Dept Gastroenterol, Coll Med, 88 Olymp Ro 43 Gil, Seoul 05505, South Korea