Platelet–Lymphocyte Ratio as a Useful Predictor of the Therapeutic Effect of Neoadjuvant Chemotherapy in Breast Cancer

BACKGROUND: The peripheral blood platelet–lymphocyte ratio (PLR) has been proposed as an indicator for evaluating systemic inflammatory responses in cancer-bearing patients. While some reports suggest a correlation between PLR and prognosis, few studies have examined the relationship between PLR and sensitivity to chemotherapy. We conducted a study on whether PLR could serve as a predictor of the therapeutic effects of neoadjuvant chemotherapy (NAC). METHODS: PLR was evaluated in 177 breast cancer patients treated with the NAC 5-fluorouracil, epirubicin and cyclophosphamide, followed by weekly paclitaxel and subsequent curative surgery. The correlation between PLR and prognosis, and between PLR and the efficacy of NAC, were evaluated retrospectively. RESULTS: The low PLR group had significantly more patients > 56 years old (p = 0.001) and postmenopausal women (p = 0.001) than the high PLR group. The low PLR group also had a higher pathologic complete response (pCR) rate (p = 0.019). On examining the correlation with prognosis, the low-PLR group was found to have significantly longer disease-free survival (p = 0.004) and overall survival (p = 0.032) than the high PLR group. Multivariate analysis also revealed that lymph node metastasis (p = 0.043, hazard ratio = 4.40) and a high PLR (p = 0.005, hazard ratio = 2.84) were independent, unfavorable prognostic factors. CONCLUSIONS: For patients with breast cancer treated with NAC, a low PLR indicated high chemotherapy sensitivity, suggesting that PLR could serve as a predictive marker of the therapeutic effect of NAC.