title: Breast cancer in Tunisia: association of body mass index with histopathological aspects of tumors.
abstract: BACKGROUND
  Previous studies have suggested a link between obesity and breast cancer (BC). However, there is no universal consensus, especially in population based studies. Because only few studies have been conducted on African women, we aimed here to assess the relationship between BMI at time of diagnosis and the BC histopathological features among Tunisian patients according to menopausal status using a hospital-based prospective cohort study.
  
  
  METHODS
  Clinical and pathological data were collected from 262 patients stratified on four groups according to their BMI. The relationship between BMI and histopathological features at diagnosis was analysed using univariate and multivariate analysis. Receiver-operating characteristic (ROC) curves were used to evaluate the performance of BMI in predicting of high tumor grade, in comparison to ki-67 index of proliferation.
  
  
  RESULTS
  Obesity was correlated with larger tumors, advanced grade and with ER-PR- Her2+ BC subtype. An association of BMI with tumor size and tumor grade was observed in both premenopausal and postmenopausal women. Additionally, a significant association between BMI and ER+, ER+PR+Her2+ and ER-PR-Her2+ status was revealed for premenopausal patients, while only ER+PR+Her2+ was associated with BMI for postmenopausal women. Finally, our results showed that compared to Ki67 proliferation index, BMI is a useful prognostic marker of high grade BC tumors.
  
  
  CONCLUSIONS
  These data are the first to show that in Tunisia obese women suffering from BC have significantly larger tumors and advanced tumor grade and that higher BMI might influence tumor characteristics and behavior.
authors.affiliation: Laboratoire de Genetique, Immunologie et Pathologies Humaines, Departement de Biologie, Faculte des Sciences de Tunis, CAMPUS, Universite Tunis-El Manar, Tunis, Tunisie E-mail : asmagati@yahoo.fr.
authors.forename: Hichem
authors.initials: H
authors.lastname: Bouguerra
authors.forename: Hajer
authors.initials: H
authors.lastname: Guissouma
authors.forename: Soumaya
authors.initials: S
authors.lastname: Labidi
authors.forename: Nejla
authors.initials: N
authors.lastname: Stambouli
authors.forename: Raja
authors.initials: R
authors.lastname: Marrakchi
authors.forename: Salem
authors.initials: S
authors.lastname: Chouaib
authors.forename: Amel
authors.initials: A
authors.lastname: Ben Ammar Elgaaied
authors.forename: Hammouda
authors.initials: H
authors.lastname: Boussen
authors.forename: Asma
authors.initials: A
authors.lastname: Gati
mesh_terms: D001823:Body Composition; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000473:pathology*; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D008875:Middle Aged; D060787:Neoplasm Grading; D009765:Obesity / Q000473:pathology*; D017698:Postmenopause; D017697:Premenopause; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D014416:Tunisia
chemical_list: D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human