title: Choosing wisely? Patterns and correlates of the use of hypofractionated whole-breast radiation therapy in the state of Michigan.
abstract: OBJECTIVE
  Given evidence from randomized trials that have established the non-inferiority of more convenient and less costly courses of hypofractionated radiotherapy to the whole breast in selected breast cancer patients who receive lumpectomy, we sought to investigate the use of hypofractionated radiation therapy and factors associated with its use in a consortium of radiation oncology practices in Michigan. We sought to determine the extent to which variation in use occurs at the physician or practice level versus the extent to which use reflects individualization based on potentially relevant patient characteristics (such as habitus, age, chemotherapy receipt, or laterality).
  
  
  METHODS
  We evaluated associations between receipt of hypofractionated radiation therapy and various patient, provider, and practice characteristics in a multilevel model.
  
  
  RESULTS
  Of 1477 patients who received lumpectomy and whole-breast radiation therapy and were registered by the Michigan Radiation Oncology Quality Consortium (MROQC) from October 2011 to December 2013, 913 had T1-2, N0 breast cancer. Of these 913, 283 (31%) received hypofractionated radiation therapy. Among the 13 practices, hypofractionated radiation therapy use ranged from 2% to 80%. On multilevel analysis, 51% of the variation in the rate of hypofractionation was attributable to the practice level, 21% to the provider level, and 28% to the patient level. On multivariable analysis, hypofractionation was more likely in patients who were older (odds ratio [OR] 2.16 for age ≥50 years, P=.007), less likely in those with larger body habitus (OR 0.52 if separation between tangent entry and exit ≥25 cm, P=.002), and more likely without chemotherapy receipt (OR 3.82, P<.001). Hypofractionation use was not higher in the last 6 months analyzed: 79 of 252 (31%) from June 2013 to December 2013 and 204 of 661 (31%) from October 2011 to May 2013 (P=.9).
  
  
  CONCLUSIONS
  Hypofractionated regimens of whole-breast radiation therapy have been variably administered in the adjuvant setting in Michigan after the publication of long-term trial results and consensus guidelines. Most of this variability is explained at the practice and provider level rather than by patient-level features, although care is being individualized to some degree.
authors.affiliation: University of Michigan, Ann Arbor, Michigan. Electronic address: rjagsi@med.umich.edu.
authors.forename: Reshma
authors.initials: R
authors.lastname: Jagsi
authors.affiliation: University of Michigan, Ann Arbor, Michigan.
authors.forename: Kent A
authors.initials: KA
authors.lastname: Griffith
authors.affiliation: Munson Medical Center, Traverse City, Michigan.
authors.forename: David
authors.initials: D
authors.lastname: Heimburger
authors.affiliation: Henry Ford Hospital, Detroit, Michigan.
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Walker
authors.affiliation: Beaumont Health System, Royal Oak, Michigan.
authors.forename: Inga S
authors.initials: IS
authors.lastname: Grills
authors.affiliation: McLaren Northern Michigan, Petoskey, Michigan.
authors.forename: Thomas
authors.initials: T
authors.lastname: Boike
authors.affiliation: University of Michigan, Ann Arbor, Michigan.
authors.forename: Mary
authors.initials: M
authors.lastname: Feng
authors.affiliation: University of Michigan, Ann Arbor, Michigan.
authors.forename: Jean M
authors.initials: JM
authors.lastname: Moran
authors.affiliation: University of Michigan, Ann Arbor, Michigan.
authors.forename: James
authors.initials: J
authors.lastname: Hayman
authors.affiliation: University of Michigan, Ann Arbor, Michigan.
authors.forename: Lori J
authors.initials: LJ
authors.lastname: Pierce
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D002173:Cancer Care Facilities / Q000706:statistics & numerical data; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D015412:Mastectomy, Segmental / Q000706:statistics & numerical data; D008824:Michigan; D008875:Middle Aged; D009367:Neoplasm Staging; D010818:Practice Patterns, Physicians' / Q000592:standards / Q000706:statistics & numerical data*; D018787:Radiation Oncology / Q000706:statistics & numerical data*; D018714:Radiotherapy, Adjuvant / Q000379:methods / Q000706:statistics & numerical data; D016032:Randomized Controlled Trials as Topic