title: Association between androgen receptor expression, Ki-67 and the 21-gene recurrence score in non-metastatic, lymph node-negative, estrogen receptor-positive and HER2-negative breast cancer.
abstract: BACKGROUND
  The mechanisms underlying the favourable prognosis of androgen receptor (AR) expression in breast cancer are unknown.
  
  
  METHODS
  The associations between the 21-gene recurrence score (RS), AR, grade, mitotic score, Ki-67 and estrogen receptor (ER) and progesterone receptor (PgR) expression were explored in sequential women with lymph node-negative, ER-positive and HER2-negative breast cancer. Statistical significance of this exploratory study was defined as p<0.10.
  
  
  RESULTS
  Analysis comprised 70 women. Most tumours had high AR expression (97% had scores >3). Median RS was 15 (range 1-53). AR expression showed a minimally significant positive correlation with ER (R=0.37), but no correlation with Ki-67 (R=-0.18). In univariable analysis, AR (p=0.01), ER (p<0.001) and PgR (p<0.001) had significant negative associations with RS. Ki-67 (p=0.16), grade (p=0.40) and mitotic score (p=0.23) showed no association with RS. Multivariable analysis showed similar associations.
  
  
  CONCLUSIONS
  AR is associated with lower RS, but not with Ki-67.
authors.affiliation: Division of Medical Oncology and Hematology, Department of Medicine, Princess Margaret Cancer Centre, University of Toronto, Toronto, Canada.
authors.forename: Francisco E
authors.initials: FE
authors.lastname: Vera-Badillo
authors.affiliation: Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Canada Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada.
authors.forename: Martin C
authors.initials: MC
authors.lastname: Chang
authors.affiliation: Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Canada.
authors.forename: Gordana
authors.initials: G
authors.lastname: Kuruzar
authors.affiliation: Medical Oncology Department and Translational Research Unit, Albacete University Hospital, Albacete, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Ocana
authors.affiliation: Division of Medical Oncology and Hematology, Department of Medicine, Princess Margaret Cancer Centre, University of Toronto, Toronto, Canada.
authors.forename: Arnoud J
authors.initials: AJ
authors.lastname: Templeton
authors.affiliation: Sector of Medical Oncology, Institute of Oncology Ljubljana, Ljubljana, Slovenia.
authors.forename: Bostjan
authors.initials: B
authors.lastname: Seruga
authors.affiliation: Division of Medical Oncology and Hematology, Department of Medicine, Princess Margaret Cancer Centre, University of Toronto, Toronto, Canada.
authors.forename: Robyn
authors.initials: R
authors.lastname: Goldstein
authors.affiliation: Division of Medical Oncology and Hematology, Department of Medicine, Princess Margaret Cancer Centre, University of Toronto, Toronto, Canada.
authors.forename: Philippe L
authors.initials: PL
authors.lastname: Bedard
authors.affiliation: Division of Medical Oncology and Hematology, Department of Medicine, Princess Margaret Cancer Centre, University of Toronto, Toronto, Canada.
authors.forename: Ian F
authors.initials: IF
authors.lastname: Tannock
authors.affiliation: Division of Medical Oncology and Hematology, Department of Medicine, Princess Margaret Cancer Centre, University of Toronto, Toronto, Canada.
authors.forename: Eitan
authors.initials: E
authors.lastname: Amir
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis* / Q000235:genetics*; D001943:Breast Neoplasms / Q000737:chemistry / Q000175:diagnosis* / Q000235:genetics / Q000473:pathology; D049109:Cell Proliferation; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis*; D016014:Linear Models; D008875:Middle Aged; D008940:Mitotic Index; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000737:chemistry / Q000235:genetics* / Q000473:pathology; D011237:Predictive Value of Tests; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D011944:Receptors, Androgen / Q000032:analysis*; D011960:Receptors, Estrogen / Q000032:analysis*; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D011944:Receptors, Androgen; D011960:Receptors, Estrogen; C410798:AR protein, human; C508053:ERBB2 protein, human
keywords: BREAST CANCER; HORMONE; MOLECULAR ONCOLOGY