[1] Peking Union Med Coll, Beijing 100021, Peoples R China
[2] Chinese Acad Med Sci, Canc Inst & Hosp, Dept Thorac Surg, Beijing, Peoples R China
[3] Chinese Acad Med Sci, Canc Inst & Hosp, Dept Pathol, Beijing, Peoples R China
[4] Peking Univ, Coll Med, Beijing, Peoples R China