title: Apolipoprotein D expression does not predict breast cancer recurrence among tamoxifen-treated patients.
abstract: BACKGROUND
  Apolipoprotein D (ApoD) has been proposed as a predictor of breast cancer recurrence among estrogen receptor-positive (ER+), tamoxifen-treated patients.
  
  
  METHODS
  We conducted a population-based case-control study nested in a population of 11,251 women aged 35-69 years at diagnosis with Stage I-III breast cancer between 1985 and 2001 on Denmark's Jutland Peninsula and registered with the Danish Breast Cancer Cooperative Group. We identified 541 recurrent or contralateral breast cancers cases among women with ER+ disease treated with tamoxifen for at least 1 year and 300 cases in women with ER- disease never treated with tamoxifen. We matched one control subject per case and assessed ApoD expression in the tumor cell nucleus and cytoplasm using tissue microarray immunohistochemistry. We computed the odds ratio (OR) associating ApoD expression with recurrence and adjusted for potential confounding using logistic regression.
  
  
  RESULTS
  Cytoplasmic ApoD expression was seen in 68% of ER+ tumors, in 66% of ER- tumors, and in 66% of controls across both groups. In women with ER+ tumors, the associations of cytoplasmic ApoD expression with recurrence (OR = 1.0; 95% CI = 0.7 to 1.4) and increasing cytoplasmic expression with recurrence (OR = 1.0; 95% CI = 0.996 to 1.003) were null, as were those for women with ER- tumors. Associations for nuclear ApoD expression and combined nuclear and cytoplasmic expression were similarly near-null.
  
  
  CONCLUSIONS
  ApoD expression is likely not a predictor of recurrence in tamoxifen-treated patients.
  
  
  CONCLUSIONS
  This study eliminates the previously suggested marker ApoD as a predictor of recurrence among tamoxifen-treated women.
authors.affiliation: Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America.
authors.forename: Daniella
authors.identifier: http://orcid.org/0000-0003-2523-4164
authors.initials: D
authors.lastname: Klebaner
authors.affiliation: Institute of Pathology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Stephen
authors.initials: S
authors.lastname: Hamilton-Dutoit
authors.affiliation: Departments of Surgery and Biochemistry, University of Vermont College of Medicine, Burlington, Vermont, United States of America.
authors.forename: Thomas
authors.initials: T
authors.lastname: Ahern
authors.affiliation: Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America.
authors.forename: Anatasha
authors.initials: A
authors.lastname: Crawford
authors.affiliation: Institute of Pathology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Jakobsen
authors.affiliation: Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark.
authors.forename: Deirdre P
authors.initials: DP
authors.lastname: Cronin-Fenton
authors.affiliation: Department of Clinical Chemistry & Pharmacology, Odense University Hospital, Odense, Denmark.
authors.forename: Per
authors.initials: P
authors.lastname: Damkier
authors.affiliation: Department of Pathology, Stavanger University Hospital, Stavanger, Norway.
authors.forename: Emiel
authors.initials: E
authors.lastname: Janssen
authors.affiliation: Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Kjaersgaard
authors.affiliation: Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark.
authors.forename: Anne Gulbech
authors.initials: AG
authors.lastname: Ording
authors.affiliation: Department of Breast and Endocrine Surgery, Stavanger University Hospital, Stavanger, Norway.|Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Håvard
authors.initials: H
authors.lastname: Søiland
authors.affiliation: Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark.
authors.forename: Henrik Toft
authors.initials: HT
authors.lastname: Sørensen
authors.affiliation: Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States of America.|Department of Clinical Epidemiology, Aarhus University, Aarhus, Denmark.
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Lash
authors.affiliation: Institute of Pathology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Ylva
authors.initials: Y
authors.lastname: Hellberg
mesh_terms: D000293:Adolescent; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D053399:Apolipoproteins D / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008875:Middle Aged; D008962:Models, Theoretical; D009364:Neoplasm Recurrence, Local; D011960:Receptors, Estrogen / Q000378:metabolism; D013629:Tamoxifen / Q000627:therapeutic use*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D053399:Apolipoproteins D; D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D013629:Tamoxifen