title: Immunohistochemical profile and clinical-pathological variables in breast cancer.
abstract: OBJECTIVE
  To describe the main characteristics of women with breast cancer, according to the immunohistochemical profile.
  
  
  METHODS
  The population comprised a hospital cohort, consisting of women diagnosed with breast cancer between 2003 and 2005 (n = 601) and treated at a referral center for cancer care in Juiz de Fora, MG, Brazil. Only 397 women who had complete immunohistochemistry analysis were selected. To define the groups according to the immunohistochemical profile, the assessment of estrogen and progesterone receptors, Ki-67 cell proliferation index, and overexpression of human epidermal growth factor receptor 2 (HER2) was chosen. According to the different phenotypes, five subtypes were defined: luminal A, luminal B HER2 negative, luminal B HER2 positive, triple negative, and HER2 overexpression.
  
  
  RESULTS
  Most patients were white (80.7%) and post-menopausal (64.9%), with a mean age of 57.4 years (± 13.5). At diagnosis, 57.5% had tumor size > 2.0 cm, and 41.7% had lymph node involvement. The most common subtypes were luminal B - HER2 negative (41.8%) and triple negative (24.2%). In the luminal A subtype, 72.1% of patients were post-menopausal, while the highest percentage of premenopausal women were observed in the luminal B - HER2 positive and triple negative subtypes (45.2% and 44.2%, respectively). A higher frequency of tumors > 2.0 cm and lymph node involvement was observed in triple negative and HER2 positive subtypes.
  
  
  CONCLUSIONS
  This study allowed the distribution assessment of the main clinical and pathological characteristics and those related to health services in a cohort of Brazilian women with breast cancer, according to the immunohistochemical tumor subtypes.
authors.affiliation: Program of Medical Residence of Hospital 9 de Julho – Instituto Oncológico de Juiz de Fora, Juiz de Fora, MG, Brazil. janerdc@terra.com.br
authors.forename: Jane Rocha Duarte
authors.initials: JR
authors.lastname: Cintra
authors.forename: Maria Teresa Bustamante
authors.initials: MT
authors.lastname: Teixeira
authors.forename: Roberta Wolp
authors.initials: RW
authors.lastname: Diniz
authors.forename: Homero
authors.initials: H
authors.lastname: Gonçalves Junior
authors.forename: Thiago Marinho
authors.initials: TM
authors.lastname: Florentino
authors.forename: Guilherme Fialho De
authors.initials: GF
authors.lastname: Freitas
authors.forename: Luiz Raphael Mota
authors.initials: LR
authors.lastname: Oliveira
authors.forename: Mariana Teodoro Dos Reis
authors.initials: MT
authors.lastname: Neves
authors.forename: Talita
authors.initials: T
authors.lastname: Pereira
authors.forename: Maximiliano Ribeiro
authors.initials: MR
authors.lastname: Guerra
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000453:epidemiology / Q000378:metabolism / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
chemical_list: D019394:Ki-67 Antigen; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human