title: Epidemiological risk factors associated with inflammatory breast cancer subtypes.
abstract: BACKGROUND
  In this single-institution case-control study, we identified risk factors associated with inflammatory breast cancer (IBC) subtypes based on staining of estrogen receptor (ER), progesterone receptor (PR) and expression of human epidermal growth factor 2 (HER2neu) to determine distinct etiologic pathways.
  
  
  METHODS
  We identified 224 women with IBC and 396 cancer-free women seen at the MD Anderson Cancer Center. Multinomial logistic regression was used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) for associations between breast cancer risk factors and the IBC tumor subtypes: luminal (ER+ and/or PR+/HER2neu-), HER2neu+ (any ER and PR, HER2neu+), and triple-negative (ER-/PR-/HER2neu-).
  
  
  RESULTS
  In multivariable analysis, compared with women age ≥26 at first pregnancy, women age <26 had a higher risk of triple-negative IBC (OR 3.32, 95% CI 1.37-8.05). Women with a history of breast-feeding had a lower risk of triple-negative (OR 0.30; 95% CI 0.15-0.62) and luminal IBC (OR 0.35, 95% CI 0.18-0.68). A history of smoking was associated with an increased risk of luminal IBC (OR 2.37; 95% CI 1.24-4.52). Compared with normal-weight women, those who were overweight or obese (body mass index ≥25 kg/m(2)) had a higher risk of all three tumor subtypes (p < 0.01 for all subtypes).
  
  
  CONCLUSIONS
  Overweight or obese status is important modifiable risk factor for IBC of any subtype. Modifiable risk factors, age at first pregnancy (≥26), breast-feeding, and smoking may be associated with specific IBC subtypes. These results highlight the importance of evaluating epidemiologic risk factors for IBC for the identification of subtype-specific prevention strategies.
authors.affiliation: Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, 1155 Pressler St., Unit 1360, P.O. Box 301439, Houston, TX, 77230, USA.|MD Anderson Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Houston, TX, USA.
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Atkinson
authors.affiliation: MD Anderson Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Houston, TX, USA.|Department of Epidemiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Randa
authors.initials: R
authors.lastname: El-Zein
authors.affiliation: MD Anderson Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Houston, TX, USA.|Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Vicente
authors.initials: V
authors.lastname: Valero
authors.affiliation: MD Anderson Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Houston, TX, USA.|Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Lucci
authors.affiliation: Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, 1155 Pressler St., Unit 1360, P.O. Box 301439, Houston, TX, 77230, USA.
authors.forename: Therese B
authors.initials: TB
authors.lastname: Bevers
authors.affiliation: MD Anderson Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Houston, TX, USA.|Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Tamer
authors.initials: T
authors.lastname: Fouad
authors.affiliation: Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, 1155 Pressler St., Unit 1360, P.O. Box 301439, Houston, TX, 77230, USA.
authors.forename: Weiqin
authors.initials: W
authors.lastname: Liao
authors.affiliation: MD Anderson Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Houston, TX, USA.|Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Naoto T
authors.initials: NT
authors.lastname: Ueno
authors.affiliation: MD Anderson Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, Houston, TX, USA.|Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Wendy A
authors.initials: WA
authors.lastname: Woodward
authors.affiliation: Department of Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, 1155 Pressler St., Unit 1360, P.O. Box 301439, Houston, TX, 77230, USA. abrewster@mdanderson.org.
authors.forename: Abenaa M
authors.initials: AM
authors.lastname: Brewster
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D001942:Breast Feeding / Q000706:statistics & numerical data; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D058922:Inflammatory Breast Neoplasms / Q000209:etiology / Q000473:pathology*; D016015:Logistic Models; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology; D011247:Pregnancy; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D012307:Risk Factors; D064726:Triple Negative Breast Neoplasms / Q000453:epidemiology / Q000473:pathology; D055815:Young Adult
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
keywords: Cancer epidemiology; Inflammatory breast cancer; Lifestyle factors; Obesity; Reproductive factors