title: Prognostic significance of CD8+ T lymphocytes in breast cancer depends upon both oestrogen receptor status and histological grade.
abstract: OBJECTIVE
  Results of previous studies on the influence of tumour infiltrating lymphocytes on prognosis of women with breast cancer have been mixed. This study re-evaluates the role of tumour-infiltrating lymphocytes as a prognostic marker in women with breast cancer.
  
  
  RESULTS
  Immunochemistry staining of CD8(+) T cells was performed on a tissue microarray of 1953 breast carcinomas. When all tumours were considered, no association between the lymphocyte count and patient survival was found. In univariate analysis, there was a reduced disease-specific survival for women with oestrogen receptor (ER)-positive tumours with high intraepithelial lymphocyte count (P=0.004). In those with ER-negative tumours, the disease-specific survival was improved when the intraepithelial, stromal and total lymphocyte counts were high, the total lymphocyte count also being an independent prognostic marker on multivariate analysis (P=0.031). When stratified by histological grade, on univariate analysis, the previously observed inferior outcome in women with high lymphocyte count and ER-positive tumours remained significant only if tumours were also of low grade, and the superior outcome in those with ER-negative tumours remained significant if tumours were also of high grade.
  
  
  CONCLUSIONS
  Our results raise the possibility of different immune-tumour interactions based on ER status and histological grade.
authors.affiliation: Department of Pathology, McGill University, Montreal, QC, Canada.
authors.forename: Kristi
authors.initials: K
authors.lastname: Baker
authors.forename: Jonathan
authors.initials: J
authors.lastname: Lachapelle
authors.forename: Inti
authors.initials: I
authors.lastname: Zlobec
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Bismar
authors.forename: Luigi
authors.initials: L
authors.lastname: Terracciano
authors.forename: William D
authors.initials: WD
authors.lastname: Foulkes
mesh_terms: D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology / Q000401:mortality; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism / Q000473:pathology*; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D053208:Kaplan-Meier Estimate; D018655:Lymphocyte Count; D016246:Lymphocytes, Tumor-Infiltrating / Q000378:metabolism / Q000473:pathology*; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism*; D015996:Survival Rate; D013557:Switzerland / Q000453:epidemiology; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D011960:Receptors, Estrogen