title: New developments in breast cancer prognosis: molecular predictors of treatment response and survival.
abstract: OBJECTIVE
  This study aimed to assess the molecular subtypes of breast cancer for patients attending a dedicated breast care center and examine the association with clinicopathological features, treatment and survival outcomes.
  
  
  METHODS
  Demographic, clinicopathological and treatment details were collected from women with primary breast cancer. Immunohistochemical subtypes were also collected. The association between breast cancer subtypes and clinicopathological features was assessed using the chi-square or Fisher's exact test. Survival outcomes were compared among subtypes with the log-rank test.
  
  
  RESULTS
  Immunohistochemical subtypes were not associated with tumor size, lymphovascular invasion or lymph node involvement but differed by histological grade (p=0.014) and nuclear grade of tumors (p=0.001). The 5-year overall survival estimates for luminal A, luminal B, HER-2-positive and triple-negative tumors were 100%, 96.2%, 71.4% and 92.3% respectively. Compared to luminal A tumors (93.4%), luminal B (80.8%), HER-2-positive (71.4%) and triple-negative (76.9%) tumors exhibited a reduced disease-free survival (DFS). Patients with ER-positive tumors had a higher DFS than their ER-negative counterparts (p=0.036). Patients with tumors expressing a low Ki-67 level had a more favorable prognosis (p=0.02).
  
  
  CONCLUSIONS
  The most prevalent luminal A subtype is associated with relatively better prognosis, whereas HER-2-positive and triple-negative tumors are prone to early relapse with diminished survival.
authors.affiliation: Department of Health Technology and Informatics, Hong Kong Polytechnic University, Hong Kong, PR China.
authors.forename: Eleanor M N
authors.initials: EM
authors.lastname: Foo
authors.forename: Maureen V
authors.initials: MV
authors.lastname: Boost
authors.forename: Anthony S W
authors.initials: AS
authors.lastname: Wong
authors.forename: Wings T Y
authors.initials: WT
authors.lastname: Loo
authors.forename: Louis W C
authors.initials: LW
authors.lastname: Chow
authors.forename: Christopher Y C
authors.initials: CY
authors.lastname: Chow
mesh_terms: D000328:Adult; D000368:Aged; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000235:genetics / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000235:genetics / Q000473:pathology; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D011960:Receptors, Estrogen / Q000235:genetics* / Q000378:metabolism; D011980:Receptors, Progesterone / Q000235:genetics* / Q000378:metabolism; D064726:Triple Negative Breast Neoplasms / Q000235:genetics* / Q000473:pathology
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human