title: Stereotactic radiotherapy (SABR) for the treatment of primary non-small cell lung cancer; systematic review and comparison with a surgical cohort.
abstract: OBJECTIVE
  To assess the efficacy of stereotactic ablative radiotherapy (SABR) for the treatment of non-small cell lung cancer (NSCLC) through a systematic review of all relevant publications from 2006 to the present compared to controls treated with surgery. In the absence of Grade I evidence, the objective outcome data should form the basis for planning future studies and commissioning SABR services.
  
  
  METHODS
  Standard systematic review methodology extracting patient and disease characteristics, treatment and outcome data from published articles reporting patient data from populations of 20 or more Stage I NSCLC patients treated with SABR with a median follow up of minimum of 1 year. The individual outcome measures were corrected for stage and summary weighted outcome data were compared to outcome data from a large International Association for the Study of Lung Cancer (IASLC) cohort matched for stage of disease with survival as the principal endpoint and local control (local progression free survival - local PFS) as the secondary endpoint.
  
  
  RESULTS
  Forty-five reports containing 3771 patients treated with SABR for NSCLC were identified that fulfilled the selection criteria; both survival and staging data were reported in 3171 patients. The 2 year survival of the 3201 patients with localized stage I NSCLC treated with SABR was 70% (95% CI: 67-72%) with a 2 year local control of 91% (95% CI: 90-93%). This was compared to a 68% (95% CI: 66-70) 2 year survival of 2038 stage I patients treated with surgery. There was no survival or local PFS difference with different radiotherapy technologies used for SABR.
  
  
  CONCLUSIONS
  Systematic review of a large cohort of patients with stage I NSCLC treated with SABR suggests that survival outcome in the short and medium term is equivalent to surgery for this population of patients regardless of co-morbidity. As selection bias cannot be assessed from the published reports and treatment related morbidity data are limited, a direct comparison between the two treatment approaches should be a priority. In the meantime, SABR can be offered to stage I patients with NSCLC as an alternative to surgery.
authors.affiliation: Harley Street at University College Hospital, London, UK.
authors.forename: Francesca
authors.initials: F
authors.lastname: Soldà
authors.forename: Mark
authors.initials: M
authors.lastname: Lodge
authors.forename: Sue
authors.initials: S
authors.lastname: Ashley
authors.forename: Alastair
authors.initials: A
authors.lastname: Whitington
authors.forename: Peter
authors.initials: P
authors.lastname: Goldstraw
authors.forename: Michael
authors.initials: M
authors.lastname: Brada
mesh_terms: D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D009367:Neoplasm Staging; D016634:Radiosurgery
keywords: Non-small cell lung cancer; Stereotactic radiotherapy; Surgery