title: Importance of Ki-67 in human epidermal growth factor receptor 2 positive breast cancer.
abstract: OBJECTIVE
  The aim of this study was to evaluate the importance of Ki-67 in Human Epidermal Growth Factor Receptor 2 (Her-2) positive breast cancer patients.
  
  
  METHODS
  We reviewed the records of patients diagnosed with Her-2-positive non-metastatic breast cancer between 2005 and 2011. Paraffin-embedded tissue samples were stained with MIB-1 mouse monoclonal antibody to find Ki-67 levels. Patients were grouped as low Ki-67<20% and high Ki-67≥20%. Demographic and clinical features were compared.
  
  
  RESULTS
  One hundred and six patients were included in the study. Median follow up time was 41 months (range 15-100). Median age was 49.5 years (range 29-79). Twenty-nine patients (27.4%) were in the Ki-67 low group. Demographic features were similar in both groups. Lymphovas cular invasion was more frequent in the Ki-67 high group, and hormone receptor (HR) positivity was more frequent in the Ki-67 low group (p=0.03, p=0.03, respectively). Recurrence rate was not significantly different in both groups (p=0.36). T stage (p=0.02), stage (p<0.01), lymphovascular invasion (p=0.02), ER status (p=0.02), and HR status (p<0.01) were related with recurrence. In multivariate analysis, stage and HR negativity were independent factors for recurrence (p<0.01, p=0.01, respectively). Recurrence sites were also similar in both groups. Survival rates at the third year for Ki-67 low group and Ki-67 high group were 94% and 92%, respectively.
  
  
  CONCLUSIONS
  Her-2 positive patients with low Ki-67 and high Ki-67 had similar demographic and pathologic features except lymphovascular invasion and HR status. HR status was an important factor for disease course. Clinical course was determined by HR status rather than Ki-67.
authors.affiliation: Department of Medical Oncology, Faculty of Medicine, Trakya University, Edirne, Turkey.
authors.forename: Bulent
authors.initials: B
authors.lastname: Erdogan
authors.forename: Esma
authors.initials: E
authors.lastname: Turkmen
authors.forename: Tülin Deniz
authors.initials: TD
authors.lastname: Yalta
authors.forename: Ufuk
authors.initials: U
authors.lastname: Usta
authors.forename: Hilmi
authors.initials: H
authors.lastname: Kodaz
authors.forename: İlhan
authors.initials: İ
authors.lastname: Hacibekiroglu
authors.forename: Ozgur
authors.initials: O
authors.lastname: Tanriverdi
authors.forename: Sernaz
authors.initials: S
authors.lastname: Uzunoglu
authors.forename: Irfan
authors.initials: I
authors.lastname: Cicin
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human