title: Higher Ki67 expression is associates with unfavorable prognostic factors and shorter survival in breast cancer.
abstract: BACKGROUND
  The prognostic value of the Ki67 expression level is yet unclear in breast cancer. The aim of this study was to investigate the association between Ki67 expression levels and prognostic factors such as grade, Her2 and hormone receptor expression status in breast cancers.
  
  
  METHODS
  Clinical and pathological features of the patients with breast cancer were retreived from the hospital records.
  
  
  RESULTS
  In this study, 163 patients with breast cancer were analyzed, with a mean age of 53.4±12.2 years. Median Ki67 positivity was 20% and Ki67-high tumors were significantly associated with high grade (p<0.001), lymphovascular invasion (p=0.001), estrogen receptor (ER) negativity (p=0.035), Her2 positivity (p=0.001), advanced stage (p<0.001) and lymph node positivity (p<0.003) . Lower Ki67 levels were significantly associated with longer median relapse-free and overall survival compared to those of higher Ki67 levels.
  
  
  CONCLUSIONS
  High Ki67 expression is associated with ER negativity, Her2 positivity, higher grade and axillary lymph node involvement in breast cancers. The level of Ki67 expression is a prognostic factor predicting relapse-free and overall survival in breast cancer patients.
authors.affiliation: Department of Medical Oncology, Hacettepe University Institute of Cancer, Turkey E-mail : skilickap@yahoo.com.
authors.forename: Saadettin
authors.initials: S
authors.lastname: Kilickap
authors.forename: Yalcin
authors.initials: Y
authors.lastname: Kaya
authors.forename: Birsen
authors.initials: B
authors.lastname: Yucel
authors.forename: Ersin
authors.initials: E
authors.lastname: Tuncer
authors.forename: Nalan Akgul
authors.initials: NA
authors.lastname: Babacan
authors.forename: Sahande
authors.initials: S
authors.lastname: Elagoz
mesh_terms: D001365:Axilla; D014408:Biomarkers, Tumor / Q000096:biosynthesis; D001943:Breast Neoplasms / Q000401:mortality / Q000473:pathology*; D049109:Cell Proliferation; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000096:biosynthesis*; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human