title: Effect of smoking during radiotherapy, respiratory insufficiency, and hemoglobin levels on outcome in patients irradiated for non-small-cell lung cancer.
abstract: OBJECTIVE
  To investigate the effect of smoking during radiotherapy (RT), respiratory insufficiency before RT, hemoglobin levels during RT, and additional factors on overall survival, locoregional control (LRC), and metastasis-free survival in non-small-cell lung cancer patients.
  
  
  METHODS
  The following factors were investigated in 181 patients who underwent RT for non-small-cell lung cancer: age, gender, Karnofsky performance score, histologic type, grade, T/N stage, American Joint Committee on Cancer stage, surgery, chemotherapy, respiratory insufficiency before RT, pack-years, smoking during RT, and hemoglobin levels during RT. Additionally, in the 129 patients who did not undergo surgery, the effect of the equivalent dose in 2-Gy fractions (EQD2) (<60 Gy vs. 60 Gy vs. >60 Gy) on outcome was investigated.
  
  
  RESULTS
  On multivariate analysis, improved overall survival was associated with a lower T stage (p = 0.004), lower N stage (p = 0.040), surgery (p = 0.010), and no respiratory insufficiency (p = 0.023). A Karnofsky performance score >70 achieved borderline significance (p = 0.056). Improved LRC was associated with a lower T stage (p = 0.007) and no smoking during RT (p = 0.029). Improved metastasis-free survival was associated with lower T stage (p < 0.001) and lower N stage (p < 0.001). In those patients who did not undergo surgery, an EQD2 of > or =60 Gy was associated with a better outcome than an EQD2 of <60 Gy. Furthermore, an EQD2 >60 Gy resulted in better LRC than did an EQD2 of < or =60 Gy.
  
  
  CONCLUSIONS
  Smoking during RT had a significant effect on LRC, but we did not find that hemoglobin levels or respiratory insufficiency significantly affected LRC or metastasis-free survival in our patient population. Furthermore, our data suggest a dose-effect relationship in those patients who did not undergo surgery.
authors.affiliation: Department of Radiation Oncology, University Hospital Schleswig-Holstein, Campus Luebeck, Luebeck, Germany. Rades.Dirk@gmx.net
authors.forename: Dirk
authors.initials: D
authors.lastname: Rades
authors.forename: Cornelia
authors.initials: C
authors.lastname: Setter
authors.forename: Steven E
authors.initials: SE
authors.lastname: Schild
authors.forename: Juergen
authors.initials: J
authors.lastname: Dunst
mesh_terms: D000328:Adult; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood / Q000401:mortality* / Q000532:radiotherapy*; D015897:Comorbidity; D005260:Female; D005858:Germany / Q000453:epidemiology; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D015994:Incidence; D008175:Lung Neoplasms / Q000097:blood / Q000401:mortality* / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods; D012131:Respiratory Insufficiency / Q000097:blood* / Q000401:mortality*; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D012907:Smoking / Q000097:blood / Q000401:mortality*; D016019:Survival Analysis; D015996:Survival Rate; D016896:Treatment Outcome
chemical_list: D006454:Hemoglobins