Association between CD8+ T-cell infiltration and breast cancer survival in 12,439 patients.

BACKGROUND: T-cell infiltration in estrogen receptor (ER)-negative breast tumours has been associated with longer survival. To investigate this association and the potential of tumour T-cell infiltration as a prognostic and predictive marker, we have conducted the largest study of T cells in breast cancer to date. PATIENTS AND METHODS: Four studies totalling 12 439 patients were used for this work. Cytotoxic (CD8+) and regulatory (forkhead box protein 3, FOXP3+) T cells were quantified using immunohistochemistry (IHC). IHC for CD8 was conducted using available material from all four studies (8978 samples) and for FOXP3 from three studies (5239 samples)-multiple imputation was used to resolve missing data from the remaining patients. Cox regression was used to test for associations with breast cancer-specific survival. RESULTS: In ER-negative tumours [triple-negative breast cancer and human epidermal growth factor receptor 2 (human epidermal growth factor receptor 2 (HER2) positive)], presence of CD8+ T cells within the tumour was associated with a 28% [95% confidence interval (CI) 16% to 38%] reduction in the hazard of breast cancer-specific mortality, and CD8+ T cells within the stroma with a 21% (95% CI 7% to 33%) reduction in hazard. In ER-positive HER2-positive tumours, CD8+ T cells within the tumour were associated with a 27% (95% CI 4% to 44%) reduction in hazard. In ER-negative disease, there was evidence for greater benefit from anthracyclines in the National Epirubicin Adjuvant Trial in patients with CD8+ tumours [hazard ratio (HR) = 0.54; 95% CI 0.37-0.79] versus CD8-negative tumours (HR = 0.87; 95% CI 0.55-1.38). The difference in effect between these subgroups was significant when limited to cases with complete data (P heterogeneity = 0.04) and approached significance in imputed data (P heterogeneity = 0.1). CONCLUSIONS: The presence of CD8+ T cells in breast cancer is associated with a significant reduction in the relative risk of death from disease in both the ER-negative [supplementary Figure S1, available at Annals of Oncology online] and the ER-positive HER2-positive subtypes. Tumour lymphocytic infiltration may improve risk stratification in breast cancer patients classified into these subtypes. NEAT ClinicalTrials.gov: NCT00003577.

The prognostic significance of B lymphocytes in invasive carcinoma of the breast.

Although the favourable role of T lymphocyte populations in different tumour types is established, that of B cells is still a matter of debate and needs further clarification. The presence of tumour-infiltrating B cells may represent an antibody response against breast tumour antigens. We used immunohistochemistry to investigate the density and localisation of B lymphocytes infiltrating 1470 breast tumours and to identify any prognostic significance and relationship to various clinicopathological factors. Higher numbers of CD20(+) cells were found in the stroma away from the carcinoma (mean 12 cells) compared with either intratumoural or adjacent stromal compartments (mean 1 cell). The majority of tumours showed a diffuse pattern of B cells rather than aggregates. There was a positive correlation between higher numbers of total CD20(+) B cells and higher tumour grade (r (s) = 0.20, P < 0.001), ER and PgR negativity (P < 0.001), and basal phenotype (P < 0.001) subclass. In univariate survival analysis, higher total number of infiltrating CD20(+) cells, irrespective of location, was associated with significantly better BCSS (P = 0.037) and longer DFI (P = 0.001). In multivariate analysis, total CD20(+) B cell count (HR = 0.75, 95% CI = 0.58-0.96 for BCSS and HR = 0.72, 95% CI = 0.58-0.89, for DFI), tumour size, nodal stage, grade, vascular invasion, HER-2 status, and total CD8(+) T cell count were independently associated with outcome. This suggests that humoral immunity, in addition to the cell mediated immunity, may be important in breast cancer. This should be considered in breast cancer immunotherapy and vaccine strategies.

Tumour-infiltrating macrophages and clinical outcome in breast cancer.

BACKGROUND: Macrophages constitute a major component of the leucocytic infiltrate of tumours. Human studies show an association between tumour-associated macrophages and tumours with poor prognostic features. In breast cancer, the presence of macrophages has been correlated with increased angiogenesis and poor prognosis but little information is available about the independent prognostic role of macrophages infiltrating breast carcinomas. AIMS AND METHODS: This study used immunohistochemistry and tissue microarrays to assess the density and localisation of CD68 macrophages infiltrating 1322 breast tumours and to identify any relationship with clinicopathological factors and patient outcome. RESULTS: Tumour-infiltrating macrophages were present in the majority of tumours with a predominantly diffuse pattern. The density of distant stromal macrophages (infiltrating stroma away from the carcinoma, median count 14 cells) was higher than intratumoural (median zero cells) and adjacent stromal macrophages (median three cells). Higher total macrophage number was associated with higher tumour grade (r(s)=0.39, p<0.001), ER and PgR negativity, HER-2 positivity and basal phenotype (p<0.001). In univariate survival analysis, higher numbers of CD68 macrophages were significantly associated with worse breast cancer-specific survival (p<0.001) and shorter disease-free interval (p=0.004). However in multivariate model analysis, the CD68 macrophage count was not an independent prognostic marker. CONCLUSIONS: Macrophages are heterogeneous with different subsets having different functions. The present study suggests that overall macrophage numbers are not related to prognosis in breast cancer. However, further studies are needed to investigate the potential role of different subsets of macrophages.