Parameters That May Predict NAC Effectiveness in Hormone-Positive Breast Cancer According to CPS Score

Objective: Neoadjuvant chemotherapy (NAC) in hormone-positive operable breast cancer supports breast-conserving surgery, axillary dissection, and survival. However, the pathological complete response (pCR) rates to NAC in hormone-positive breast cancer remain low. Identifying the predictive parameters for pathological response prior to NAC is crucial. In this study, we investigated clinical, pathological, inflammatory, and metabolic parameters that could predict NAC response and survival. Material and Methods: A retrospective study was conducted on 120 patients with hormone-positive breast cancer. Clinical and pathological stages of patients who underwent surgery following NAC were used to calculate the CPS score (clinical stage score + pathological stage score). The Kruskal Wallis test was employed to compare clinical, pathological, and laboratory parameters with the CPS score. The Bonferroni test was applied for post-hoc analysis. Categorical variables were compared using the Pearson Chi-Square test or Fisher’s exact test. Results: There was no statistically significant association between the CPS score and age (p=0.106), estrogen receptor positivity (p=0.331), grade (p=0.100), Ki67 (p=0.247), and chemotherapy received (p=0.720). While pCR was statistically significant in univariate analysis (p=0.001), it did not reach statistical significance in the multivariate model (p=0.258). Axillary pathological response (ypN) had a statistically significant correlation with the CPS score (p=0.003). There was no statistically significant association between the CPS score and leukocyte, lymphocyte, neutrophil, or platelet counts, glucose levels, NLR, PNI, or SII values (p > 0.05). Conclusion: ypN was associated with the CPS score in predicting survival following NAC in hormone-positive breast cancer. No statistically significant association was observed between inflammatory or metabolic parameters and the CPS score. Further validation in larger studies is warranted.