[1] Gunma Univ, Dept Resp Med, Grad Sch Med, Maebashi, Gunma, Japan
[2] Shimane Univ Hosp, Dept Internal Med, Div Med Oncol & Resp Med, Izumo, Shimane, Japan
[3] St Marianna Univ, Dept Pathol, Sch Med, Kawasaki, Kanagawa, Japan
[4] St Marianna Univ, Dept Internal Med, Sch Med, Div Resp Med, Kawasaki, Kanagawa, Japan