title: Real-world patterns of endocrine therapy for metastatic hormone-receptor-positive (HR+)/human epidermal growth factor receptor-2-negative (HER2-) breast cancer patients in the United States: 2002-2012.
abstract: OBJECTIVE
  Clinical guidelines recommend that patients with HR+/HER2- metastatic breast cancer (mBC), the most prevalent mBC subtype, receive three lines of endocrine therapy (ET) prior to transitioning to chemotherapy (CT) in the absence of need for rapid response, symptomatic visceral disease, or suspected endocrine resistance. Little is known about real-world ET treatment patterns among HR+/HER2- mBC patients.
  
  
  METHODS
  Post-menopausal women with HR+/HER2- mBC were identified in the MarketScan databases (2002Q3-2012Q2). Patients were classified as receiving either ET or CT as their first therapy post-mBC diagnosis. Those receiving ET were studied further and stratified into three subgroups based on which of the following events occurred first: transition to CT, discontinuation of ET (90 days without evidence of ET), or end of data or insurance eligibility.
  
  
  METHODS
  Mean numbers of lines of ET and median durations of each line were summarized for the overall sample and subgroups.
  
  
  RESULTS
  Among a total of 19,120 HR+/HER2- mBC patients, 11,545 (60%) initiated an ET; median follow-up time for these patients was 17 months. Seventy-four percent did not receive a second ET. The average patient received 1.36 lines of ET. Among patients with 2+ lines of ET, the duration of each subsequent line was significantly shorter than the previous line. RESULTS were similar in all subgroups.
  
  
  CONCLUSIONS
  Clinical characteristics and reasons for treatment choices are unavailable in claims data.
  
  
  CONCLUSIONS
  Fewer than two thirds of patients initiated treatment for HR+/HER2- mBC with ET. Among those who did, most received only one line of ET before discontinuation or transition to CT. Patients who received multiple lines of ET experienced shorter durations of therapy with each line. Real-world treatment with ET falls short of the targets recommended by guidelines, representing unmet need for treatment options that improve the effectiveness of endocrine therapy.
authors.affiliation: Analysis Group Inc. , Boston, MA , USA.
authors.forename: Elyse
authors.initials: E
authors.lastname: Swallow
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Darren
authors.initials: D
authors.lastname: Thomason
authors.forename: Ruo-Ding
authors.initials: RD
authors.lastname: Tan
authors.forename: Andrew
authors.initials: A
authors.lastname: Kageleiry
authors.forename: James
authors.initials: J
authors.lastname: Signorovitch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D016208:Databases, Factual; D004334:Drug Administration Schedule; D005260:Female; D005500:Follow-Up Studies; D019983:Guideline Adherence / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D009362:Neoplasm Metastasis; D017698:Postmenopause; D017410:Practice Guidelines as Topic; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D012189:Retrospective Studies; D014481:United States
chemical_list: D018931:Antineoplastic Agents, Hormonal; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
keywords: Breast cancer; Chemotherapy; Endocrine therapy; HR+ HER2− metastatic breast cancer; Treatment patterns