title: Height, sitting height, and leg length in relation with breast cancer risk in the E3N cohort.
abstract: BACKGROUND
  If height is a well-established risk factor for breast cancer, leg length and sitting height are usually considered as better candidate biomarkers of growth hormone exposure than height, respectively, in pre- and postpuberty.
  
  
  METHODS
  Risk of breast cancer associated with quartiles of height, sitting height, and leg length were estimated in the French E3N cohort (N = 50,704, including 2,065 breast cancer cases), stratified on both menopausal and hormone receptor statuses.
  
  
  RESULTS
  Height was associated with an increased postmenopausal breast cancer risk [HR = 1.22 (1.06-1.41) when comparing extreme categories, P(trend) = 0.002], which was exclusively driven by the association with leg length [HR = 1.21 (1.05-1.39), P(trend) = 0.013] and not sitting height [HR = 1.03 (0.89-1.18), P(trend) = 0.379]. Leg length was associated with an increased ER(+) breast cancer risk in postmenopausal [HR = 1.24 (1.06-1.46), P(trend) = 0.004], whereas sitting height was associated with a borderline decreased ER(-) premenopausal breast cancer risk [HR = 0.45 (0.20-1.01), P(trend) = 0.011]. The positive associations observed in the overall population between leg length and breast cancer risk were actually restricted to women who had a short birth length [HR = 1.82 (1.22-2.72), P(trend) = 0.022] and those with a low birth weight [HR = 1.43 (1.00-2.04), P(trend) = 0.054].
  
  
  CONCLUSIONS
  The two components of height risk are differentially associated with breast cancer risk: leg length with an increased risk of postmenopausal ER(+) tumors and sitting height with a decreased risk of premenopausal ER(-) tumors.
  
  
  CONCLUSIONS
  Future prospective studies should no longer consider height a single risk factor for breast cancer risk.
authors.affiliation: INSERM (Institut National de la Santé et de la Recherche Médicale) U1018, Center for Research in Epidemiology and Population Health (CESP), 94805 Villejuif Cedex, France.
authors.forename: Guy
authors.initials: G
authors.lastname: Fagherazzi
authors.forename: Alice
authors.initials: A
authors.lastname: Vilier
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Boutron-Ruault
authors.forename: Françoise
authors.initials: F
authors.lastname: Clavel-Chapelon
authors.forename: Sylvie
authors.initials: S
authors.lastname: Mesrine
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis*; D001724:Birth Weight; D001827:Body Height; D001943:Breast Neoplasms / Q000453:epidemiology / Q000209:etiology*; D015331:Cohort Studies; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D007866:Leg / Q000033:anatomy & histology*; D008875:Middle Aged; D017698:Postmenopause; D017697:Premenopause; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D018570:Risk Assessment; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone