title: Outcome Disparities in African American Compared with European American Women with ER+HER2- Tumors Treated within an Equal-Access Health Care System.
abstract: OBJECTIVE
  Breast cancer mortality rates are higher for African American women (AAW) than for any other ethnic group in the United States. Recent reports suggest that outcome disparities between AAW and European American women (EAW) are present in the ER+HER2- subtype. To improve our understanding, pathological characteristics, mortality and molecular profiles from women treated within an equal-access health care system were evaluated.
  
  
  METHODS
  All AAW (n=90) and EAW (n=308) with ER+HER2- tumors were identified. Gene expression profiles were generated from primary breast tumors from 57 AAW and 181 EAW. Pathological characteristics, survival and gene expression analysis were evaluated using chi-square analysis, log-rank tests and ANOVA.
  
  
  RESULTS
  Tumors from AAW were significantly more likely to be PR-, Ki67+ and of higher grade. Tumor stage, size and lymph node status did not differ significantly, nor did mortality rates (P=.879). At the molecular level, genes PSPHL and CRYBB2P1 were expressed at significantly higher levels in tumor tissues as well as normal stroma and blood from AAW. Polymorphisms controlling expression of each gene were identified with minor allele frequencies differing significantly between populations but not between cases and controls within each population.
  
  
  CONCLUSIONS
  Survival disparities were not detected in patients with ER+HER2- tumors treated within an equal-access health care system and molecular differences in tumors were not causal. Thus, outcome disparities in AAW with ER+HER2- tumors are largely attributable to socioeconomic factors affecting access to screening and treatment, rather than reflecting underlying biological differences.
authors.affiliation: Chan Soon-Shiong Institute of Molecular Medicine at Windber, Windber, Penn.
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Costantino
authors.affiliation: Clinical Breast Care Project, Murtha Cancer Center, Bethesda, Md.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Freeman
authors.affiliation: Clinical Breast Care Project, Murtha Cancer Center, Bethesda, Md.
authors.forename: Craig D
authors.initials: CD
authors.lastname: Shriver
authors.affiliation: Clinical Breast Care Project, Murtha Cancer Center, Windber, Penn.
authors.forename: Rachel E
authors.initials: RE
authors.lastname: Ellsworth
mesh_terms: D000328:Adult; D001741:Black or African American; D000368:Aged; D001943:Breast Neoplasms / Q000208:ethnology* / Q000235:genetics / Q000628:therapy; D005260:Female; D006297:Health Services Accessibility; D054625:Healthcare Disparities; D006801:Humans; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism; D012959:Socioeconomic Factors; D016019:Survival Analysis; D059467:Transcriptome; D014481:United States; D044465:White People
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; C508053:ERBB2 protein, human
keywords: African American; Breast Cancer; Disparities; Luminal A