title: Stereotactic body radiotherapy for primary lung cancer at a dose of 50 Gy total in five fractions to the periphery of the planning target volume calculated using a superposition algorithm.
abstract: OBJECTIVE
  To retrospectively analyze the clinical outcomes of stereotactic body radiotherapy (SBRT) for patients with Stages 1A and 1B non-small-cell lung cancer.
  
  
  METHODS
  We reviewed the records of patients with non-small-cell lung cancer treated with curative intent between Dec 2001 and May 2007. All patients had histopathologically or cytologically confirmed disease, increased levels of tumor markers, and/or positive findings on fluorodeoxyglucose positron emission tomography. Staging studies identified their disease as Stage 1A or 1B. Performance status was 2 or less according to World Health Organization guidelines in all cases. The prescribed dose of 50 Gy total in five fractions, calculated by using a superposition algorithm, was defined for the periphery of the planning target volume.
  
  
  RESULTS
  One hundred twenty-one patients underwent SBRT during the study period, and 63 were eligible for this analysis. Thirty-eight patients had Stage 1A (T1N0M0) and 25 had Stage 1B (T2N0M0). Forty-nine patients were not appropriate candidates for surgery because of chronic pulmonary disease. Median follow-up of these 49 patients was 31 months (range, 10-72 months). The 3-year local control, disease-free, and overall survival rates in patients with Stages 1A and 1B were 93% and 96% (p = 0.86), 76% and 77% (p = 0.83), and 90% and 63% (p = 0.09), respectively. No acute toxicity was observed. Grade 2 or higher radiation pneumonitis was experienced by 3 patients, and 1 of them had fatal bacterial pneumonia.
  
  
  CONCLUSIONS
  The SBRT at 50 Gy total in five fractions to the periphery of the planning target volume calculated by using a superposition algorithm is feasible. High local control rates were achieved for both T2 and T1 tumors.
authors.affiliation: Department of Radiology, Ofuna Chuo Hospital, Kamakura, Japan; Department of Radiology, Tokyo Metropolitan Hiroo General Hospital, Tokyo, Japan.
authors.forename: Atsuya
authors.initials: A
authors.lastname: Takeda
authors.forename: Naoko
authors.initials: N
authors.lastname: Sanuki
authors.forename: Etsuo
authors.initials: E
authors.lastname: Kunieda
authors.forename: Toshio
authors.initials: T
authors.lastname: Ohashi
authors.forename: Yohei
authors.initials: Y
authors.lastname: Oku
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Takeda
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Shigematsu
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kubo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000601:surgery; D009367:Neoplasm Staging; D017564:Radiation Pneumonitis / Q000188:drug therapy / Q000209:etiology; D011859:Radiography; D016634:Radiosurgery / Q000379:methods* / Q000401:mortality; D012062:Relative Biological Effectiveness; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D047368:Tumor Burden