title: One decade later: trends and disparities in the application of post-mastectomy radiotherapy since the release of the American Society of Clinical Oncology clinical practice guidelines.
abstract: OBJECTIVE
  In 2001 ASCO published practice guidelines for post mastectomy radiotherapy (PMRT). We analyzed factors that influence the receipt of radiotherapy therapy and trends over time.
  
  
  METHODS
  We analyzed 8889 women who underwent mastectomy as primary surgical treatment for stage II or III breast cancer between 1995 and 2008 using data from the Kentucky Cancer Registry. We categorized patients according to ASCO group: group 1, PMRT not routinely recommended (T2, N0); group 2, PMRT controversial/evidence insufficient (T1-2, N1); group 3, PMRT recommended or suggested (T3-4 or N2-3). Probability of receiving PMRT was assessed using logistic regression.
  
  
  RESULTS
  Overall, 24.0% of women received PMRT over the study period. The rates of PMRT for group 1, 2, and 3 were 7.5%, 19.5%, and 47.3%, respectively. Since 2001, there was an increase in the use of PMRT (from 21.1%-26.5%, P<.0001), which occurred mainly among group 3 members (from 40.8%-51.2%, P<.0001). The average rate remained constant in group 1 (from 7.1%-7.4%, P=.266) and decreased in group 2 (from 20.0%-18.1%, P<.0001). On multivariate analysis, the rate of PMRT was significantly lower for women aged >70 years (vs. younger), rural Appalachia (vs. non-Appalachia) populations, and Medicaid (vs. privately insured) patients.
  
  
  CONCLUSIONS
  ASCO guidelines have influenced practice in an underserved state; however PMRT remains underused, even for highest-risk patients. Barriers exist for elderly, rural and poor patients, which independently predict for lack of adequate care. Updated guidelines are needed to clarify the use of PMRT for patients with T1-2, N1 disease.
authors: Department of Radiation Oncology, James Graham Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY, USA. aedrag01@louisville.edu
authors: Anthony E
authors: AE
authors: Dragun
authors: Bin
authors: B
authors: Huang
authors: Saurabh
authors: S
authors: Gupta
authors: John B
authors: JB
authors: Crew
authors: Thomas C
authors: TC
authors: Tucker
mesh_terms: D000367:Age Factors; D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D005260:Female; D019983:Guideline Adherence / Q000706:statistics & numerical data / Q000639:trends*; D006801:Humans; D007629:Kentucky; D016015:Logistic Models; D008197:Lymph Node Excision / Q000706:statistics & numerical data; D008408:Mastectomy; D008507:Medically Underserved Area; D008875:Middle Aged; D015999:Multivariate Analysis; D011184:Postoperative Period; D017410:Practice Guidelines as Topic; D018787:Radiation Oncology / Q000592:standards; D018714:Radiotherapy, Adjuvant / Q000706:statistics & numerical data / Q000639:trends*; D012955:Societies, Medical / Q000592:standards; D014481:United States