title: The cost of adjuvant chemotherapy in patients with early-stage breast carcinoma.
abstract: BACKGROUND
  In the U.S., the majority of premenopausal patients with early-stage breast carcinoma are treated with adjuvant chemotherapy. However, to the authors' knowledge, there have been few formal analyses of adjuvant chemotherapy cost performed to date, especially in premenopausal women. The objective of the current study was to evaluate the direct medical cost of adjuvant chemotherapy in women with early-stage breast carcinoma.
  
  
  METHODS
  The attributable cost of adjuvant chemotherapy was evaluated by comparing the total cost of care for patients with breast carcinoma (cases) during the period from diagnosis to 9 months subsequent with the cost for age-matched and gender-matched control patients without breast carcinoma over an equivalent time period. The authors identified cases from a linked database of claims records from a managed care organization, and the Cancer Surveillance System registry. Controls were identified from the managed care organization from which the cases originated. Resource prices were based on reimbursements from the managed care organization.
  
  
  RESULTS
  The attributable cost of adjuvant chemotherapy was estimated to be dollar 23,019 (95% confidence interval, dollar 19,596-dollar 26,441), based on 1239 women. The cost appeared to decrease with increasing age at diagnosis, with total costs of dollar 26,834, dollar 19,889, and dollar 17,098 for women < 50, 50-59, and > or = 60 years, respectively. Also, costs were higher for regional versus local disease (dollar 36,076 vs. dollar 12,659), for women who had a mastectomy versus breast-conserving surgery (dollar 31,075 vs. dollar 17,889), and for women who had no comorbidities versus > or = 1 comorbidity (dollar 23,606 vs. dollar 21,340). Contributors to high chemotherapy cost included use of chemotherapy agents not included in clinical guidelines during the study period, use of supportive care agents, and hospitalizations.
  
  
  CONCLUSIONS
  The attributable cost of adjuvant chemotherapy in patients with early-stage breast carcinoma is significant. The integration of managed care claims data with clinical data from the Cancer Surveillance System registry offered a unique opportunity to derive more informative and accurate disease burden estimates in oncology.
authors.affiliation: Division of Research, Kaiser Permanente, Oakland, California 94612, USA. Nina.Oestreicher@kp.org
authors.forename: Nina
authors.initials: N
authors.lastname: Oestreicher
authors.forename: Scott D
authors.initials: SD
authors.lastname: Ramsey
authors.forename: Jeannine S
authors.initials: JS
authors.lastname: McCune
authors.forename: Hannah M
authors.initials: HM
authors.lastname: Linden
authors.forename: David L
authors.initials: DL
authors.lastname: Veenstra
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D016022:Case-Control Studies; D017024:Chemotherapy, Adjuvant / Q000191:economics*; D003365:Costs and Cost Analysis; D005260:Female; D017048:Health Care Costs; D006801:Humans; D008875:Middle Aged; D017697:Premenopause