title: The use of adjuvant radiotherapy in elderly patients with early-stage breast cancer: changes in practice patterns after publication of Cancer and Leukemia Group B 9343.
abstract: BACKGROUND
  The Cancer and Leukemia Group B (CALGB) 9343 randomized phase 3 trial established lumpectomy and adjuvant therapy with tamoxifen alone, rather than both radiotherapy and tamoxifen, as a reasonable treatment course for women aged >70 years with clinical stage I (AJCC 7th edition), estrogen receptor-positive breast cancer. An analysis of the Surveillance, Epidemiology, and End Results (SEER) registry was undertaken to assess practice patterns before and after the publication of this landmark study.
  
  
  METHODS
  The SEER database from 2000 to 2009 was used to identify 40,583 women aged ≥70 years who were treated with breast-conserving surgery for clinical stage I, estrogen receptor-positive and/or progesterone receptor-positive breast cancer. The percentage of patients receiving radiotherapy and the type of radiotherapy delivered was assessed over time. Administration of radiotherapy was further assessed across age groups; SEER cohort; and tumor size, grade, and laterality.
  
  
  RESULTS
  Approximately 68.6% of patients treated between 2000 and 2004 compared with 61.7% of patients who were treated between 2005 and 2009 received some form of adjuvant radiotherapy (P < .001). Coinciding with a decline in the use of external beam radiotherapy, there was an increase in the use of implant radiotherapy from 1.4% between 2000 and 2004 to 6.2% between 2005 to 2009 (P < .001). There were significant reductions in the frequency of radiotherapy delivery over time across age groups, tumor size, and tumor grade and regardless of laterality (P < .001 for all).
  
  
  CONCLUSIONS
  Randomized phase 3 data support the omission of adjuvant radiotherapy in elderly women with early-stage breast cancer. Analysis of practice patterns before and after the publication of these data indicates a significant decline in radiotherapy use; however, nearly two-thirds of women continue to receive adjuvant radiotherapy.
authors.affiliation: Department of Radiation Oncology, Duke University, Durham, North Carolina.
authors.forename: Manisha
authors.initials: M
authors.lastname: Palta
authors.forename: Priya
authors.initials: P
authors.lastname: Palta
authors.forename: Nrupen A
authors.initials: NA
authors.lastname: Bhavsar
authors.forename: Janet K
authors.initials: JK
authors.lastname: Horton
authors.forename: Rachel C
authors.initials: RC
authors.lastname: Blitzblau
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000473:pathology* / Q000532:radiotherapy* / Q000601:surgery; D017326:Clinical Trials, Phase III as Topic; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D059351:Organ Sparing Treatments / Q000379:methods*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data / Q000639:trends*; D018714:Radiotherapy, Adjuvant / Q000706:statistics & numerical data*; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D018426:SEER Program; D013629:Tamoxifen / Q000627:therapeutic use*; D016896:Treatment Outcome; D014481:United States
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen
keywords: Cancer and Leukemia Group B (CALGB) 9343; breast cancer; elderly; radiotherapy; use