title: Which is the optimal biologically effective dose of stereotactic body radiotherapy for Stage I non-small-cell lung cancer? A meta-analysis.
abstract: OBJECTIVE
  To assess the relationship between biologically effective dose (BED) and efficacy of stereotactic body radiation therapy (SBRT) and to explore the optimal BED range for Stage I non-small-cell lung cancer (NSCLC).
  
  
  METHODS
  Eligible studies were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through June 2010. According to the quartile of included studies, BED was divided into four dose groups: low (<83.2 Gy), medium (83.2-106 Gy), medium to high (106-146 Gy), high (>146 Gy). To obtain pooled estimates of overall survival (OS), cancer-specific survival (CSS), and local control rate (LCR), data were combined in a random effect model. Pooled estimates were corrected for the percentage of small tumors (<3 cm).
  
  
  RESULTS
  Thirty-four observational studies with a total of 2,587 patients were included in the meta-analysis. Corrected pooled estimates of 2- or 3-year OS in the medium BED (76.1%, 63.5%) or the medium to high BED (68.3%, 63.2%) groups were higher than in the low (62.3%, 51.9%) or high groups (55.9%, 49.5%), respectively (p ≤ 0.004). Corrected 3-year CSS in the medium (79.5%), medium to high (80.6%), and high groups (90.0%) were higher than in the low group (70.1%, p = 0.016, 0.018, 0.001, respectively).
  
  
  CONCLUSIONS
  The OS for the medium or medium to high BED groups were higher than those for the low or high BED group for SBRT in Stage I NSCLC. The medium or medium to high BED (range, 83.2-146 Gy) for SBRT may currently be more beneficial and reasonable in Stage I NSCLC.
authors.affiliation: Department of Radiation Oncology, Cancer Hospital, Tianjin Medical University, Tianjin, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Fujun
authors.initials: F
authors.lastname: Yang
authors.forename: Baosheng
authors.initials: B
authors.lastname: Li
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Dongqing
authors.initials: D
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Yi
authors.forename: Juan
authors.initials: J
authors.lastname: Wang
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology / Q000601:surgery*; D009367:Neoplasm Staging; D016634:Radiosurgery / Q000379:methods*; D011879:Radiotherapy Dosage; D012062:Relative Biological Effectiveness