Dynamic Changes in Peripheral Systemic Immunity Markers During Chemotherapy in HER2-negative Advanced Breast Cancer.

BACKGROUND/AIM:The immune system has a pivotal role in modulating the response to chemotherapy in breast cancer (BC). However, the immune status during chemotherapy remains unclear. We evaluated the sequential changes in peripheral systemic immunity markers in BC patients treated with various chemotherapeutic agents. MATERIALS AND METHODS:We examined the correlation between the peripheral systemic immunity markers, neutrophil-to-lymphocyte ratio (NLR), absolute lymphocyte count (ALC) and the local cytolytic activity (CYT) score obtained by quantitative reverse-transcription polymerase chain reaction of 84 preoperative BC patients. Next, we observed the sequential changes in the peripheral systemic immunity markers during treatment with four anticancer drugs: oral 5-fluorouracil derivative; S-1, epirubicin plus cyclophosphamide; paclitaxel plus the anti-vascular endothelial growth factor antibody bevacizumab, and eribulin in 172 HER2-negative advanced BC patients. Finally, we examined the correlation between the changes in the peripheral systemic immunity markers, time to treatment failure (TTF) and progression-free survival (PFS). RESULTS:A negative correlation was found between ALC and NLR. ALC-low and NLR-high cases were positively associated with CYT score-low cases. The ratio of ALC-increase and NLR-decrease varies depending on the anticancer drugs used. The responder group (TTF ≥3 months) had a higher NLR-decrease ratio than the nonresponder group (TTF <3 months). Patients with a high NLR-decrease ratio showed higher PFS. CONCLUSION:The change in ALC or NLR varies according to the anticancer drugs, suggesting differential immunomodulatory effects of the drugs. Furthermore, the change in NLR reflects the therapeutic efficacy of chemotherapy in advanced BC.