title: Factors affecting the local control of stereotactic body radiotherapy for lung tumors including primary lung cancer and metastatic lung tumors.
abstract: OBJECTIVE
  To identify factors affecting local control of stereotactic body radiotherapy (SBRT) for lung tumors including primary lung cancer and metastatic lung tumors.
  
  
  METHODS
  Between June 2006 and June 2009, 159 lung tumors in 144 patients (primary lung cancer, 128; metastatic lung tumor, 31) were treated with SBRT with 48-60 Gy (mean 50.1 Gy) in 4-5 fractions. Higher doses were given to larger tumors and metastatic tumors in principle. Assessed factors were age, gender, tumor origin (primary vs. metastatic), histological subtype, tumor size, tumor appearance (solid vs. ground glass opacity), maximum standardized uptake value of positron emission tomography using (18)F-fluoro-2-deoxy-D: -glucose, and SBRT doses.
  
  
  RESULTS
  Follow-up time was 1-60 months (median 18 months). The 1-, 2-, and 3-year local failure-free rates of all lesions were 90, 80, and 77 %, respectively. On univariate analysis, metastatic tumors (p < 0.0001), solid tumors (p = 0.0246), and higher SBRT doses (p = 0.0334) were the statistically significant unfavorable factors for local control. On multivariate analysis, only tumor origin was statistically significant (p = 0.0027). The 2-year local failure-free rates of primary lung cancer and metastatic lung tumors were 87 and 50 %, respectively.
  
  
  CONCLUSIONS
  A metastatic tumor was the only independently significant unfavorable factor for local control after SBRT.
authors.affiliation: Department of Radiation Therapy, National Hospital Organization Shikoku Cancer Center, Kou-160, Minamiumemoto-Machi, Matsuyama, Ehime 791-0280, Japan. yahamamot@gmail.com
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hamamoto
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kataoka
authors.forename: Motohiro
authors.initials: M
authors.lastname: Yamashita
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Nogami
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Sugawara
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kozuki
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sawada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suehisa
authors.forename: Syuichi
authors.initials: S
authors.lastname: Shinohara
authors.forename: Naomi
authors.initials: N
authors.lastname: Nakajima
authors.forename: Tetsu
authors.initials: T
authors.lastname: Shinkai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000556:secondary* / Q000601:surgery*; D008297:Male; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D016634:Radiosurgery; D011879:Radiotherapy Dosage; D014057:Tomography, X-Ray Computed