Pathological Complete Response to Neoadjuvant Chemotherapy in Patients With Breast Cancer: The Relationship Between Inflammatory Biomarkers and Molecular Subtypes

Purpose Among patients with breast cancer, pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) is an important prognostic predictor of survival. This study aimed to investigate the relationship between platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR) along with overall pCR. Method A total of 150 patients with breast cancer who were first administered NAC and then operated on were retrospectively evaluated. Neutrophil-lymphocyte ratio and PLR obtained from the complete blood count analysis performed immediately before NAC treatment were analyzed. The cut-off value was calculated as 150 for PLR and 2.24 for NLR. We studied the predictive value of NLR and PLR levels for the pathologic response of breast cancer to NAC:. Results Pathological complete response was observed in 34.7% (n = 52) of the patients, pCR in the breast in 42.7% (n = 64), and that in the axilla in 44% (n = 66). There was a statistically significant difference between the pCR rates according to the PLR levels (p = 0.013). In addition, a statistically significant difference was found in the pCR rates in the breast and axilla according to PLR levels (p = 0.018, p = 0.009). Patients with low PLR in the human epidermal growth factor receptor 2 (HER-2) group had significantly higher axillary pCR rates than in those with high PLR (p = 0.019). Conclusions A low PLR level showed high chemotherapy sensitivity independent of molecular subtypes in the treatment of breast cancer with NAC. The PLR level can serve as a predictive marker of the therapeutic effect of NAC on the breast and axilla. Low PLR levels in HER-2 enriched groups can predict pCR in the axilla.