The prognostic and predictive value of tumor-infiltrating lymphocytes and hematologic parameters in patients with breast cancer.

Background: Carcinogenesis and tumor growth are associated with chronic inflammation and the host immune system. Here, we investigated the clinical significance and relationship between tumor-infiltrating lymphocytes (TILs) and hematologic parameters in patients with breast cancer.

Methods: Invasive ductal breast cancer patients (N = 145) who underwent surgery were retrospectively evaluated. Samples were obtained using a core needle biopsy for CD8+, FOXP3+ TIL assessment. Blood lymphocytes, neutrophils, monocytes, and platelets were obtained by peripheral venous punctures.

Results: CD8 + TILs were significantly associated with absolute lymphocyte count (ALC) and the absolute monocyte count (AMC). Low LMR (ALC/AMC) (cut-off - 5.3, range = 0.73-12.31) was associated with poor overall survival (OS) (p = 0.010), disease-free survival (DFS) (p = 0.005). However, in subgroup analysis, LMR did not have any value as a prognostic factor in HER2-positive breast cancers. TILs had different prognostic impacts across breast cancer subtypes, although they were not statistically significant. The treatment response after NAC tended to improve in breast cancer patients with high FOXP3+ TILs, low NLR (neutrophil count/ALC) (FOXP3 p for trend = 0.006, NLR p for trend = 0.063).

Conclusions: A relevance between TILs and hematologic parameters in breast cancer was demonstrated. The influence of the immune system on breast cancer progression may differ by subtype.