title: The evolving role of adjuvant radiotherapy for elderly women with early-stage breast cancer.
abstract: BACKGROUND
  Elderly patients with early-stage breast cancer (ESBC) derive a local control benefit from radiotherapy (RT) after lumpectomy, without any apparent effect on overall survival. Therefore, the use of RT is controversial. In the current study, the authors characterized updated trends in RT for elderly patients with estrogen receptor (ER)-positive ESBC.
  
  
  METHODS
  Patients aged ≥70 years with ER-positive ESBC measuring ≤2 cm after lumpectomy with negative resection margins and known RT details were identified in the National Cancer Data Base. Patients were classified by year of diagnosis and segregated into 3 groups relative to the initial publication and updated presentation of the Cancer and Leukemia Group B (CALGB) 9343 trial. RT use overall, prescription of hypofractionated RT, and use of boost RT were compared between groups using logistic regression analysis, and the influence of clinicopathologic covariates was determined with multivariable logistic regression analysis.
  
  
  RESULTS
  A total of 122,796 elderly patients with ER-positive ESBC who were diagnosed between 1998 and 2011 were identified. Overall, 84,649 patients (68.9%) received adjuvant RT, with a decline observed between successive cohorts (71.3% in the pre-initial publication cohort, 69.5% in the pre-update cohort, and 64.7% in the post-update cohort; P <.001). Hypofractionated RT use increased among treated patients over time (P<.001). Boost RT was used in 67.5% of patients, with a decline noted between the pre-update and post-update cohorts (68.7% vs 57.7%; P<.001). Overall RT use as well as use of boost RT were found to be lower among older patients and those with lower-grade or smaller tumors (P<.001), whereas hypofractionated RT was used more commonly in these groups (P<.001).
  
  
  CONCLUSIONS
  RT use appears to have declined in elderly patients with ER-positive ESBC, a finding that is reflective of evidence-based practice integrating mature trial data. Further research is needed to develop tools to aid in the decision-making process regarding the delivery or avoidance of RT in this setting.
authors: Department of Therapeutic Radiology, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Charles E
authors: CE
authors: Rutter
authors: Department of Therapeutic Radiology, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Nataniel H
authors: NH
authors: Lester-Coll
authors: Department of Therapeutic Radiology, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Brandon R
authors: BR
authors: Mancini
authors: Department of Therapeutic Radiology, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Christopher D
authors: CD
authors: Corso
authors: Department of Therapeutic Radiology, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Henry S
authors: HS
authors: Park
authors: Department of Therapeutic Radiology, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Debra N
authors: DN
authors: Yeboa
authors: Cancer Outcomes, Public Policy, and Effectiveness Research Center, Yale School of Medicine, Yale University, New Haven, Connecticut.|Department of Medicine, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Cary P
authors: CP
authors: Gross
authors: Department of Therapeutic Radiology, Yale School of Medicine, Yale University, New Haven, Connecticut.|Cancer Outcomes, Public Policy, and Effectiveness Research Center, Yale School of Medicine, Yale University, New Haven, Connecticut.
authors: Suzanne B
authors: SB
authors: Evans
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000532:radiotherapy*; D003657:Decision Making; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D015412:Mastectomy, Segmental; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D018714:Radiotherapy, Adjuvant; D011960:Receptors, Estrogen / Q000032:analysis; D016896:Treatment Outcome
chemical_list: D011960:Receptors, Estrogen
keywords: Cancer and Leukemia Group B (CALGB) 9343; boost; elderly; radiation