198P - Association of types of treatment modalities with expression of T Lymphocytes (CD4, CD8, Treg) in breast cancer patients and their clinical outcome

Background

Women with breast cancer with impaired immunity develop life-threatening clinical disease. Findings of tumor-associated lymphocytes in tumor specimens are explicit evidence of immunologic sensitivity to this. Despite several treatment modalities, the majority of patients eventually relapse. However, immunotherapy – a new promising modality for treatment - has been advocated to command disease progress. Cancer immunoediting provided insights that the immune system has both immune surveillance and tumor promotion effects during cancer development. Anti-tumor immune response requires involvement of both CD4+ and CD8+ T cells. Thus, for better understanding the roles of CD4+ CD8 and regulatory T cells in pathogenesis and progression of breast cancer, the following study was designed to be conducted in clinical patients with breast cancer. 1-To determine expression of FOXP3 CD25, CD4, CD8 before therapy in blood, and tumor tissue. 2-Impact of surgery and chemotherapy on immunological status of tumour in breast cancer patients.

Methods

This was a prospective observational pilot study. Patients: N=30, locally advanced and metastatic breast cancer patients receiving chemotherapy as first modality of treatment (NACT group). N=30, early breast cancer patients receiving surgery as first modality of treatment (Upfront surgery). Control: N=30, Sex matched group undergoing surgery for benign breast disease.

Results

In the pre-treatment group lower expression of CD4 and higher CD8 and Tregs were found as the disease progresses. After upfront surgery CD4 counts increase with decrease of CD8 and Tregs cells. There was no change in CD4 in the control after surgery with positive correlation in CD8 and Tregs. Higher CD4 counts with lower CD8 and Tregs were found in patients after NACT.

Conclusions

T-cell subgroups in breast cancer patients undergo dynamic, significant changes during surgery and chemotherapy. Comprehensive analysis of characteristic T cell repertoire in breast cancer has depicted a landscape of possibilities of developing a blood-based therapeutic or preventive (vaccine) modality to enhance the armamentarium against this cancer.

Legal entity responsible for the study

AIIMS.

Funding

AIIMS New Delhi.

Disclosure

The author declared no conflicts of interest.