Distribution of CXCR4 and tumour-infiltrating lymphocytes in breast cancer subtypes; their relationship with each other, axillary lymph node involvement, and other prognostic indicators

Nodal status in luminal A invasive breast cancer: relationships with cytotoxic CD8 + and regulatory FOXP3 + cells tumor-associated infiltrate and other prognostic factors

Luminal A breast cancers are generally associated with low metastatic potential and good prognosis. However, there is a proportion of patients, who present with metastases in lymph nodes. The aim of our study was to determine the association between the number of positive lymph nodes and infiltrates of tumor-associated cytotoxic CD8 + (CTLs), regulatory FOXP3 + T cells (Tregs), as well as other prognostic factors. Immunohistochemistry (IHC) for CD8 + and FOXP3 + was performed in 87 formalin-fixed paraffin-embedded primary breast cancer tissues, and cell infiltrate was assessed under light microscope. We observed that node-positive cases were associated with higher numbers of Treg cells and lower CTL/Treg ratio. There was also an inverse correlation between the CTL/Treg ratio and the number of metastatic lymph nodes. Similar relationships were found between the number of metastatic lymph nodes and Treg density or CTL/Treg ratio in pT1 BC. An elevated intratumoral CTL/Treg ratio was associated with pN0 stage. The relationship between lymphovascular invasion (LVI) and Treg density was also noted in node-negative tumors. In addition, more advanced nodal stage was related to LVI, higher pT, and lower PR expression. The numbers of CD8 + and FOXP3 + were also associated with tumor size, histologic grade, PR expression, and mitotic index. The results of our study suggested that the levels of tumor-infiltrating regulatory and cytotoxic cells as well as the balance between them play a role in lymphovascular spread of luminal A breast cancers.

Can Tumor-Infiltrating Lymphocytes (TILs) Be a Predictive Factor for Lymph Nodes Status in Both Early Stage and Locally Advanced Breast Cancer?

The status of axillary lymph nodes is an important prognostic factor in the outcome of breast cancer tumors. New trials changed the attitude towards axillary clearance. In the era of development of new immune therapies for breast cancer, it is important to identify a biomarker that can predict lymph node status. Tumor-infiltrating lymphocytes (TILs) are a valuable indicator of the immune microenvironment that plays the central role in new anticancer drugs. Although the correlation between TILs and response to chemotherapy was established by previous studies, our retrospective study investigated the correlation between TILs and lymph node status. We analyzed data on 172 patients. According to stage, patients were divided in two groups: patients who underwent primary surgical treatment (breast-conserving or mastectomy and sentinel lymph node (SLN) biopsy +/− axillary clearance in conformity with lymph node status) and patients who received chemotherapy prior to surgical treatment (breast-conserving or mastectomy + axillary clearance). We showed a good inverse correlation between TILs and lymph nodes status for both early stage and locally advanced breast cancers. Moreover, TILs are a predictor for positive lymph nodes in the axilla in patients undergoing axillary clearance after SLN biopsy, with no statistical difference between the intrinsic or histological subtype of breast cancers. We also obtained a significant correlation between TILs and response to chemotherapy with no significative difference according to histological subtype. Although further data have still to be gathered before meeting the criteria for clinical utility, this study demonstrates that TILs are one of the most accredited forthcoming biomarkers for breast cancer (BC) patients.