title: Examining the cost-effectiveness of radiation therapy among older women with favorable-risk breast cancer.
abstract: BACKGROUND
  Little is known about the cost-effectiveness of external beam radiation therapy (EBRT) or newer radiation therapy (RT) modalities such as intensity modulated radiation (IMRT) or brachytherapy among older women with favorable-risk breast cancer.
  
  
  METHODS
  Using a Markov model, we estimated the cost-effectiveness of no RT, EBRT, and IMRT over 10 years. We estimated the incremental cost-effectiveness ratio (ICER) of IMRT compared with EBRT under different scenarios to determine the necessary improvement in effectiveness for newer modalities to be cost-effective. We estimated model inputs using women in the Surveillance, Epidemiology, and End Results-Medicare database fulfilling the Cancer and Leukemia Group B C9343 trial criteria.
  
  
  RESULTS
  The incremental cost of EBRT compared with no RT was $9500 with an ICER of $44600 per quality-adjusted life year (QALY) gained. The ICERs increased with age, ranging from $38300 (age 70-74 years) to $55800 (age 80 to 94 years) per QALY. The ICERs increased to more than $63800 per QALY for women aged 70 to 74 years with an expected 10-year survival of 25%. Reduction in local recurrence by IMRT compared with EBRT did not have a substantial impact on the ICER of IMRT. IMRT would have to increase the utility of baseline state by 20% to be cost-effective (<$100000 per QALY).
  
  
  CONCLUSIONS
  EBRT is cost-effective for older women with favorable risk breast cancer, but substantially less cost-effective for women with shorter expected survival. Newer RT modalities would have to be substantially more effective than existing therapies in improving quality of life to be cost-effective.
authors.affiliation: Affiliations of authors: Cancer Outcomes, Public Policy and Effectiveness Research (COPPER) Center, Yale Cancer Center (SS, S-YW, PRS, JBL, KBR, JBY, SBE, ABC, CPG), Department of Epidemiology and Public Health (S-YW), Section of General Internal Medicine, Department of Internal Medicine (PRS, JBL, CPG), Department of Therapeutic Radiology (KBR, JBY, SBE), and Department of Surgery (ABC), Yale University School of Medicine, New Haven, CT; Department of Health Policy and Management, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD (KDF).
authors.forename: Sounok
authors.initials: S
authors.lastname: Sen
authors.forename: Shi-Yi
authors.initials: SY
authors.lastname: Wang
authors.forename: Pamela R
authors.initials: PR
authors.lastname: Soulos
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Frick
authors.forename: Jessica B
authors.initials: JB
authors.lastname: Long
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Roberts
authors.forename: James B
authors.initials: JB
authors.lastname: Yu
authors.forename: Suzanne B
authors.initials: SB
authors.lastname: Evans
authors.forename: Anees B
authors.initials: AB
authors.lastname: Chagpar
authors.forename: Cary P
authors.initials: CP
authors.lastname: Gross
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000191:economics*; D001943:Breast Neoplasms / Q000191:economics* / Q000473:pathology / Q000532:radiotherapy*; D015897:Comorbidity; D003362:Cost-Benefit Analysis; D005260:Female; D005102:Health Expenditures; D006801:Humans; D008017:Life Expectancy; D006278:Medicare; D009364:Neoplasm Recurrence, Local / Q000191:economics / Q000517:prevention & control*; D009367:Neoplasm Staging; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D050397:Radiotherapy, Intensity-Modulated / Q000191:economics*; D018570:Risk Assessment; D012307:Risk Factors; D018426:SEER Program; D012494:Sampling Studies; D014481:United States