title: Short-term outcome of primary operated early breast cancer by hormone and HER-2 receptors.
abstract: BACKGROUND
  Prognostic subgroup classification of operable breast cancers using cDNA clustering of breast cancer-related genes resembles the classification based on the combined immunohistochemical (IHC) expression of the hormone and HER-2 receptors. We here report the short-term disease-free interval (DFI) of operable breast cancers by their joint hormone receptor/HER-2 phenotype.
  
  
  METHODS
  Short-term follow-up (FU) of a prospective cohort of 1,958 breast-cancer patients primary operated at our institution between 2000 and 2005. Receptors were evaluated using IHC. Steroid receptors were considered positive for any nuclear staining; HER-2 for strong (3+) membrane staining or positive fluorescence in situ hybridization (FISH). Kaplan-Meier (KM) DFI curves were calculated for any relapse defined as a local, regional, contralateral, or distant breast cancer event for the six predefined breast cancer subgroups: ER + PR + HER-2 - (PPN), ER + PR - HER-2 - (PNN), ER + PR + HER-2 + (PPP), ER - PR - HER-2 - (NNN), ER - PR - HER-2 + (NNP), and ER + PR - HER-2 + (PNP). P-values were calculated for comparison of the six different survival curves using two possible adaptations for multiple testing. A multivariate model for the receptors predicting DFI did incorporate local and systemic adjuvant therapy.
  
  
  RESULTS
  Median patient age was 57 years (ranges 26-96) and median FU was 3.35 years. Overall, DFI at median FU was 91%; 94% for PPN, 89% for PNN, 86% for NNN, 81% for PPP, 80% for PNP, and 76% for NNP cases. Some receptor subgroups had a significantly better DFI than others based on multiple testing, especially when the PPN group was compared against the four most frequent subtypes. The multivariate model with local and systemic adjuvant therapy confirmed the prognostic value of ER, PR, and HER-2 for short-term DFI.
  
  
  CONCLUSIONS
  It is possible to distinguish short-term prognostic breast cancer subgroups only on the basis of ER, PR, and HER-2 even when stratified for local and systemic adjuvant therapy. While gene expression profiles based on microarray data of over hundreds of genes will probably teach us much about breast cancer biology, heterogeneity, and prognosis, we emphasize the important short-term prognostic value of currently used IHC markers for ER, PR, and HER-2.
authors.affiliation: Multidisciplinary Breast Centre, UZLeuven, Leuven 3000, Belgium.
authors.forename: Olivier
authors.initials: O
authors.lastname: Brouckaert
authors.forename: Saskia
authors.initials: S
authors.lastname: Pintens
authors.forename: Vanya
authors.initials: V
authors.lastname: Van Belle
authors.forename: Sabine
authors.initials: S
authors.lastname: Van Huffel
authors.forename: Edward
authors.initials: E
authors.lastname: Camerlynck
authors.forename: Frédéric
authors.initials: F
authors.lastname: Amant
authors.forename: Karin
authors.initials: K
authors.lastname: Leunen
authors.forename: An
authors.initials: A
authors.lastname: Smeets
authors.forename: Patrick
authors.initials: P
authors.lastname: Berteloot
authors.forename: Erik
authors.initials: E
authors.lastname: Van Limbergen
authors.forename: Julie
authors.initials: J
authors.lastname: Decock
authors.forename: Wouter
authors.initials: W
authors.lastname: Hendrickx
authors.forename: Caroline
authors.initials: C
authors.lastname: Weltens
authors.forename: Walter
authors.initials: W
authors.lastname: Van den Bogaert
authors.forename: Isabelle
authors.initials: I
authors.lastname: Vanden Bempt
authors.forename: Maria
authors.initials: M
authors.lastname: Drijkoningen
authors.forename: Robert
authors.initials: R
authors.lastname: Paridaens
authors.forename: Hans
authors.initials: H
authors.lastname: Wildiers
authors.forename: Ignace
authors.initials: I
authors.lastname: Vergote
authors.forename: Marie-Rose
authors.initials: MR
authors.lastname: Christiaens
authors.forename: Patrick
authors.initials: P
authors.lastname: Neven
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000601:surgery; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D010641:Phenotype; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone