title: The Role of Patient Factors, Cancer Characteristics, and Treatment Patterns in the Cost of Care for Medicare Beneficiaries with Breast Cancer.
abstract: OBJECTIVE
  To characterize Medicare expenditures on initial breast cancer care and examine variation in expenditures across hospital referral regions (HRRs).
  
  
  METHODS
  We identified 29,110 women with localized breast cancer diagnosed in 2005-2008 and matched controls from the Surveillance, Epidemiology, and End Results-Medicare linked database.
  
  
  METHODS
  Using hierarchical generalized linear models, we estimated per patient Medicare expenditure on initial breast cancer care across HRRs and assessed the contribution of patient, cancer, and treatment factors to regional variation via incremental models.
  
  
  RESULTS
  Mean Medicare expenditure for initial breast cancer care was $19,255 per patient. The average expenditures varied from $15,053 in the lowest-spending HRR quintile to $23,480 in the highest-spending HRR quintile. Patient sociodemographic, comorbidity, and tumor characteristics explained only 1.8 percent of the difference in expenditures between the lowest- and highest-spending quintiles, while use of specific treatment modalities explained 14.5 percent of the difference. Medicare spending on radiation therapy differed the most across the quintiles, with the use of intensity modulated radiation therapy increasing from 1.7 percent in the lowest-spending quintile to 11.6 percent in the highest-spending quintile.
  
  
  CONCLUSIONS
  Medicare expenditures on initial breast cancer care vary substantially across regions. Treatment factors are major contributors to the variation.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT.
authors.forename: Xiao
authors.initials: X
authors.lastname: Xu
authors.affiliation: Division of Cardiology, Yale University School of Medicine, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.|Health Research & Educational Trust, Chicago, IL.
authors.forename: Jeph
authors.initials: J
authors.lastname: Herrin
authors.affiliation: Section of General Internal Medicine, Department of Internal Medicine, Yale University School of Medicine, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Pamela R
authors.initials: PR
authors.lastname: Soulos
authors.affiliation: Department of Chronic Disease Epidemiology, Yale University School of Public Health, New Haven, CT.
authors.forename: Avantika
authors.initials: A
authors.lastname: Saraf
authors.affiliation: Department of Therapeutic Radiology, Yale University School of Medicine, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Roberts
authors.affiliation: Department of Surgery, Yale University School of Medicine, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Brigid K
authors.initials: BK
authors.lastname: Killelea
authors.affiliation: Department of Chronic Disease Epidemiology, Yale University School of Public Health, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Shi-Yi
authors.initials: SY
authors.lastname: Wang
authors.affiliation: Section of General Internal Medicine, Department of Internal Medicine, Yale University School of Medicine, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Jessica B
authors.initials: JB
authors.lastname: Long
authors.affiliation: Department of Chronic Disease Epidemiology, Yale University School of Public Health, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Rong
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Chronic Disease Epidemiology, Yale University School of Public Health, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Ma
authors.affiliation: Section of General Internal Medicine, Department of Internal Medicine, Yale University School of Medicine, Yale Cancer Outcomes, Public Policy and Effectiveness Research Center, New Haven, CT.
authors.forename: Cary P
authors.initials: CP
authors.lastname: Gross
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000191:economics* / Q000473:pathology / Q000628:therapy*; D015897:Comorbidity; D005260:Female; D005102:Health Expenditures; D006801:Humans; D006278:Medicare / Q000191:economics*; D012189:Retrospective Studies; D018426:SEER Program; D012959:Socioeconomic Factors; D014481:United States
keywords: Breast cancer; cost; hospital referral region; radiation; variation