Background: The importance of lymphocyte subtypes in determining outcome in primary operable ductal invasive breast cancer remains unclear. The aim of present study was to examine the relationship between tumour lymphocyte subsets infiltrate and standard clinico-pathological factors and survival in patients with primary operable invasive ductal breast cancer.
Methods: The analysis of the inflammatory cell infiltrate, including lymphocyte subtypes, was undertaken using immunohistochemical techniques and visual quantitative and semi-quantitative techniques in 338 patients with ductal breast cancer.
Results: The majority (91%) of patients had high grade inflammatory cell infiltrate. The median follow-up of the survivors was 164 months. During this period, 65 died of their cancer. On univariate analysis, tumour inflammatory cell infiltrate, macrophages infiltrate (P<0.05), lymphocytic infiltrate (P<0.001) and CD8+ T-lymphocytic infiltrate (P<0.01) were associated with improved cancer-specific survival, whereas neutrophil (P<0.05) and CD138+ B-lymphocytic infiltrate (P<0.001) were associated with poorer cancer-specific survival. On multivariate analysis, tumour lymphocytic infiltrate (P<0.001), macrophage infiltrate (P<0.05), CD8+ T-lymphocytic infiltrate (P<0.01) and CD138+ B-lymphocytic infiltrate (P<0.001) were independently associated with cancer survival. When the significant inflammatory cell types were included with tumour-based factors in multivariate analysis only tumour size (Hazard ratios (HR): 2.55, 95% confidence interval (CI): 1.53-4.27, P<0.001), Ki-67 index (HR: 2.08, 95% CI: 1.08-4.00, P<0.05), lymphovascular invasion (HR: 4.40, 95% CI: 2.07-9.35, P<0.001), macrophage infiltrate (HR: 0.49, 95% CI: 0.33-0.73, P<0.001), lymphocytic infiltrate (HR: 0.11, 95% CI: 0.05-0.23, P<0.001), CD8+ T-lymphocytic infiltrate (HR: 0.57, 95% CI: 0.38-0.87, P<0.001) and CD138+ B-lymphocytic infiltrate (HR: 2.86, 95% CI: 1.79-4.56, P<0.001) were independently associated with cancer survival.
Conclusion: The majority of patients with invasive ductal breast cancer had high-grade inflammatory cell infiltrate. In these patients, inflammatory cells including macrophage and lymphocytic infiltrate, and subsets CD8+ T-lymphocytic infiltrate and CD138+ B-lymphocytic infiltrate had superior prognostic value, compared with hormone status and lymph node involvement in patients with primary operable invasive ductal breast cancer.