[1] UCL, Med Phys & Biomed Engn, London, England
[2] Chinese Acad Med Sci, Canc Hosp, Natl Clin Res Ctr Canc, Natl Canc Ctr, Shenzhen, Peoples R China
[3] Chinese Acad Med Sci, Shenzhen Hosp, Shenzhen, Peoples R China
[4] Peking Union Med Coll, Radiat Oncol, Shenzhen, Peoples R China
[5] William Beaumont Hosp, Radiat Oncol, Royal Oak, MI USA