title: Molecular Phenotype of Breast Cancer According to Time Since Last Pregnancy in a Large Cohort of Young Women.
abstract: BACKGROUND
  The increase in breast cancer risk during pregnancy and postpartum is well known; however, the molecular phenotype of breast cancers occurring shortly after pregnancy has not been well studied. Given this, we investigated whether nulliparity and the time interval since pregnancy among parous women affects the breast cancer phenotype in young women.
  
  
  METHODS
  We examined molecular phenotype in relation to time since pregnancy in a prospective cohort of 707 young women (aged ≤40 years) with breast cancer. Parity was ascertained from study questionnaires. Using tumor histologic grade on central review and biomarker expression, cancers were categorized as luminal A- or B-like, HER2 enriched, and triple negative.
  
  
  RESULTS
  Overall, 32% were luminal A-like, 41% were luminal B-like, 9% were HER2 enriched, and 18% were triple negative. Although, numerically, patients diagnosed >5 years after pregnancy had more luminal A-like subtypes than women with shorter intervals since pregnancy, there was no evidence of a relationship between these intervals and molecular subtypes once family history of breast cancer and age at diagnosis were considered.
  
  
  CONCLUSIONS
  Distribution of breast cancer molecular phenotype did not differ significantly among young women by parity or time interval since parturition when important predictors of tumor phenotype such as age and family history were considered.
  
  
  CONCLUSIONS
  Distribution of breast cancer molecular phenotype did not differ among parous young women by time interval since pregnancy. The implication of these findings for clinical practice suggests that pregnancy-associated breast cancers may be seen up to 5 years beyond parturition.
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA lcollins@bidmc.harvard.edu.
authors.forename: Laura C
authors.initials: LC
authors.lastname: Collins
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Shari
authors.initials: S
authors.lastname: Gelber
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Marotti
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: White
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Ruddy
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Elena F
authors.initials: EF
authors.lastname: Brachtel
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Lidia
authors.initials: L
authors.lastname: Schapira
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Come
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Virginia F
authors.initials: VF
authors.lastname: Borges
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Pepper
authors.initials: P
authors.lastname: Schedin
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Ellen
authors.initials: E
authors.lastname: Warner
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Taylor
authors.initials: T
authors.lastname: Wensley
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Rulla M
authors.initials: RM
authors.lastname: Tamimi
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Eric P
authors.initials: EP
authors.lastname: Winer
authors.affiliation: Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA; Dana-Farber Cancer Institute, Boston, Massachusetts, USA; Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA; University Hospitals Case Medical Center, Cleveland, Ohio, USA; Harvard Medical School, Boston, Massachusetts, USA; Mayo Clinic, Rochester, Minnesota, USA; Massachusetts General Hospital, Boston, Massachusetts, USA; University of Colorado Cancer Center, Aurora, Colorado, USA; Oregon Health & Science University, Portland, Oregon, USA; Sunnybrook Odette Cancer Centre, Toronto, Ontario, Canada; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA; Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: Ann H
authors.initials: AH
authors.lastname: Partridge
mesh_terms: D000293:Adolescent; D000328:Adult; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D010298:Parity; D011247:Pregnancy; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D017584:Reproductive History; D055815:Young Adult
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
keywords: Breast cancer; Molecular phenotypes; Pregnancy-associated breast cancer; Young women