title: Ki-67 is a prognostic marker for hormone receptor positive tumors.
abstract: OBJECTIVE
  To evaluate the utility of Ki67 as a prognostic marker in Luminal B node-negative breast cancer patients.
  
  
  METHODS
  We identified 888 patients with invasive breast carcinomas who underwent surgery between 1997 and 2004. Several classical factors were collected: age, tumor size, node involvement, tumor grade, estrogen and progesterone receptors, HER2 and Ki-67 expression. We analyzed if these parameters could be considered as a prognostic factor. In early Luminal B group, we investigated which of the following biological features provide information about bad prognosis: lack of progesterone receptor expression, HER2 overexpression/amplification or high Ki-67 value.
  
  
  RESULTS
  The majority of patients were alive and without relapse of tumor at the moment of the analysis (70 %). The prognostic factors founded in multivariate analysis were: tumor size, node involvement, grade 3 and Ki-67 expression. When we stratified the sample by immunohistochemistry (IHC) in tumor subtypes, we assessed 680 patients and we observed 191 Luminal B tumors. The biological parameter related to the worst survival in absence of nodal involvement was Ki-67 value.
  
  
  CONCLUSIONS
  Ki-67 represents an additional predictor of survival in Luminal B node negative breast cancer. Conversely, neither Progesterone-receptor nor HER2 status proved prognostic significance in this group in our study.
authors.affiliation: Department of Oncology, University Hospital of Ourense, University of Vigo, C/Ramón Puga 52-54, 32005, Ourense, Spain. maria.eva.perez.lopez@sergas.es.
authors.forename: M E
authors.identifier: http://orcid.org/0000-0003-0498-7626
authors.initials: ME
authors.lastname: Pérez-López
authors.affiliation: Department of Oncology, University Hospital of Ourense, University of Vigo, C/Ramón Puga 52-54, 32005, Ourense, Spain.
authors.forename: J
authors.initials: J
authors.lastname: García-Gómez
authors.affiliation: Research Unit, University Hospital of Ourense, University of Vigo, Ourense, Spain.
authors.forename: M T
authors.initials: MT
authors.lastname: Alves
authors.affiliation: Department of Pathology, University Hospital of Ourense, University of Vigo, Ourense, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Paradela
authors.affiliation: Department of Oncology, University Hospital of Ourense, University of Vigo, C/Ramón Puga 52-54, 32005, Ourense, Spain.
authors.forename: J
authors.initials: J
authors.lastname: García-Mata
authors.affiliation: Department of Morphological Sciences, School of Medicine-University Clinical Hospital, University of Santiago de Compostela, Ourense, Spain.
authors.forename: T
authors.initials: T
authors.lastname: García-Caballero
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology; D002288:Adenocarcinoma, Mucinous / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000473:pathology; D018275:Carcinoma, Lobular / Q000378:metabolism / Q000473:pathology; D018276:Carcinoma, Medullary / Q000378:metabolism / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D019394:Ki-67 Antigen / Q000378:metabolism*; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone
keywords: Immunohistochemistry; Ki-67; Overall survival; Prognostic factor; Tumor proliferation marker