title: Tumor biology in older breast cancer patients--what is the impact on survival stratified for guideline adherence? A retrospective multi-centre cohort study of 5378 patients.
abstract: OBJECTIVE
  The tumor biology of older breast cancer patients (oBCP) is usually less aggressive, however applied adjuvant treatment is often less potent resulting in an impaired disease free survival and overall survival in this group. This study tries to answer the following questions for the biological subtypes of oBCP (70+ y):
  
  
  METHODS
  Between 1992 and 2008 the BRENDA ('BRENDA' = quality of BREast caNcer care unDer evidence-bAsed guidelines) study group recorded medical data of 17 participating certified breast cancer centers in Germany. We performed a retrospective multi-center database analysis of 5632 patient records. Guideline-adherent-treatment (GL+) of oBCP(n = 1918) was compared to GL+ of yBCP(n = 3714).
  
  
  RESULTS
  OBCP were more likely to have hormone receptor positive (HR+) and HER2neu negative (HER2-) breast cancer (77.5% vs 74.5%). The rate of GL- was significantly different (p < 0.001) between the age groups and the biological subgroups (yBCP vs oBCP: 21.8%vs38.8% (HR+/HER2-); 30.6%vs49.7% (HR+/HER2+); 23.6%vs69.5% (HR-/HER2+); 31.4%vs67.8% (TNBC)). The survival parameters for HR+/HER2- and TNBC were significantly worse in case of GL- regarding chemotherapy, and if applicable endocrine therapy. A similar association only existed in HR-/HER2+ tumors for GL- for radiotherapy and in HR+/HER2+ tumors for chemotherapy.
  
  
  CONCLUSIONS
  Beside the significantly different distribution of biological subtypes in the age groups there is an association between biological subtype, and GL+ influencing survival parameters in oBCP.
authors.affiliation: Universität Ulm, Klinik für Frauenheilkunde und Geburtshilfe, Prittwitzstr. 43, 89075 Ulm, Germany. Electronic address: florian.ebner@uniklinik-ulm.de.
authors.forename: Florian
authors.initials: F
authors.lastname: Ebner
authors.affiliation: Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Institut für Medizinische Biometrie, Epidemiologie und Informatik (IMBEI), Obere Zahlbacher Str. 69, 55131 Mainz, Germany; Universität Mainz, Institut für Wirtschaftswissenschaften, Jakob-Welder-Weg 4, 55128 Mainz, Germany.
authors.forename: Reyn
authors.initials: R
authors.lastname: van Ewijk
authors.affiliation: Universität Würzburg, Frauenklinik und Poliklinik, Josef-Schneider-Str. 4, Haus C15, 97080 Würzburg, Germany.
authors.forename: Achim
authors.initials: A
authors.lastname: Wöckel
authors.affiliation: Universität Ulm, Klinik für Frauenheilkunde und Geburtshilfe, Prittwitzstr. 43, 89075 Ulm, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Hancke
authors.affiliation: Universität Ulm, Klinik für Frauenheilkunde und Geburtshilfe, Prittwitzstr. 43, 89075 Ulm, Germany.
authors.forename: Lukas
authors.initials: L
authors.lastname: Schwentner
authors.affiliation: Universität Ulm, Klinik für Frauenheilkunde und Geburtshilfe, Prittwitzstr. 43, 89075 Ulm, Germany.
authors.forename: Visnja
authors.initials: V
authors.lastname: Fink
authors.affiliation: Universität Ulm, Klinik für Frauenheilkunde und Geburtshilfe, Prittwitzstr. 43, 89075 Ulm, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Kreienberg
authors.affiliation: Universität Ulm, Klinik für Frauenheilkunde und Geburtshilfe, Prittwitzstr. 43, 89075 Ulm, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Janni
authors.affiliation: Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Institut für Medizinische Biometrie, Epidemiologie und Informatik (IMBEI), Obere Zahlbacher Str. 69, 55131 Mainz, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Blettner
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000592:standards; D001943:Breast Neoplasms / Q000737:chemistry / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D017024:Chemotherapy, Adjuvant / Q000592:standards; D005260:Female; D005858:Germany; D019983:Guideline Adherence / Q000706:statistics & numerical data*; D062489:Health Impact Assessment / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000401:mortality; D018719:Erb-b2 Receptor Tyrosine Kinases; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases
keywords: Breast cancer; Elderly; Guideline; Older; Survival