title: Prophylactic cranial irradiation in elderly patients with small cell lung cancer: findings from a North Central Cancer Treatment Group pooled analysis.
abstract: OBJECTIVE
  To examine the efficacy of prophylactic cranial irradiation (PCI) in elderly patients with small cell lung cancer (SCLC) (≥70 years of age) from a pooled analysis of four prospective trials.
  
  
  METHODS
  One hundred fifty-five patients with SCLC (limited stage, LSCLC, and extensive stage, ESCLC) participated in four phase II or III trials. Ninety-one patients received PCI (30 Gy/15 or 25 Gy/10) and 64 patients did not receive PCI. Survival was compared in a landmark analysis that included only patients who had stable disease or better in response to primary therapy.
  
  
  RESULTS
  Patients who received PCI had better survival than patients who did not receive PCI (median survival 12.0 months vs. 7.6 months, 3-year overall survival 13.2% vs. 3.1%, HR = 0.53 [95% CI 0.36-0.78], p = 0.001). On multivariate analysis of the entire cohort, the only factor that remained significant for survival was stage (ESCLC vs. LSCLC, p = 0.0072). In contrast, the multivariate analysis of patients who had ESCLC revealed that PCI was the sole factor associated with a survival advantage (HR = 0.47 [95% CI 0.24-0.93], p = 0.03). Grade 3 or higher adverse events (AEs) were significantly greater in patients who received PCI (71.4% vs. 47.5%, p = 0.0031), with non-neuro and non-heme being the specific AE categories most strongly correlated with PCI delivery.
  
  
  CONCLUSIONS
  PCI was associated with a significant improvement in survival for our entire elderly SCLC patient cohort on univariate analysis. Multivariate analysis suggested that the survival advantage remained significant in patients with ESCLC. PCI was also associated with a modest increase in grade 3 or higher AEs.
authors.affiliation: Department of Radiation Oncology, Mayo Clinic Arizona, USA. Electronic address: rule.william@mayo.edu.
authors.forename: William G
authors.initials: WG
authors.lastname: Rule
authors.affiliation: Section of Biomedical Statistics and Informatics, Mayo Clinic Rochester, USA.
authors.forename: Nathan R
authors.initials: NR
authors.lastname: Foster
authors.affiliation: Section of Biomedical Statistics and Informatics, Mayo Clinic Rochester, USA.
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Meyers
authors.affiliation: Department of Radiation Oncology, Mayo Clinic Arizona, USA.
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Ashman
authors.affiliation: Department of Radiation Oncology, Mayo Clinic Arizona, USA.
authors.forename: Sujay A
authors.initials: SA
authors.lastname: Vora
authors.affiliation: Department of Radiation Oncology, Mayo Clinic Rochester, USA.
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Kozelsky
authors.affiliation: Department of Radiation Oncology, Mayo Clinic Rochester, USA.
authors.forename: Yolanda I
authors.initials: YI
authors.lastname: Garces
authors.affiliation: Department of Radiation Oncology, Wake Forest School of Medicine, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Urbanic
authors.affiliation: Department of Radiation Oncology, Duke University School of Medicine, USA.
authors.forename: Joseph K
authors.initials: JK
authors.lastname: Salama
authors.affiliation: Department of Radiation Oncology, Mayo Clinic Arizona, USA.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Schild
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000401:mortality / Q000517:prevention & control* / Q000556:secondary; D016371:Cranial Irradiation / Q000379:methods*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology*; D008297:Male; D015999:Multivariate Analysis; D055752:Small Cell Lung Carcinoma / Q000401:mortality / Q000517:prevention & control* / Q000556:secondary; D016896:Treatment Outcome
keywords: PCI; Prophylactic cranial irradiation; Small cell lung cancer