Clinicopathological Predictors of Pathologic Complete Response in Triple-Negative Breast Cancer: Impact of Platinum-Based Neoadjuvant Chemotherapy

Aim: This retrospective cohort study aimed to assess the association between platinum-based neoadjuvant chemotherapy and pathologic complete response (pCR) rates, and to identify predictors of pCR in women with triple-negative breast cancer (TNBC).Material and Methods: We retrospectively analyzed 219 women with histologically confirmed TNBC who received neoadjuvant chemotherapy at a single institution between 2015 and 2024. Clinicopathological data, including age, menopausal status, tumor grade, Ki-67 proliferation index, and treatment regimen (platinum-or non-platinum-based), were evaluated. Logistic regression analyses were performed to identify independent predictors of pCR, and Kaplan–Meier survival analysis was used to assess the association between pCR and survival.Results: The overall pCR rate was 26.5%. Patients receiving platinum-based chemotherapy achieved significantly higher pCR rates than those treated without platinum (33.0% vs. 20.4%, p = 0.034). In multivariate analysis, younger age at diagnosis and a higher Ki-67 proliferation index independently predicted pCR. Platinum-based chemotherapy and postmenopausal status demonstrated clinically relevant but statistically non-significant trends toward higher pCR rates. Achieving pCR was significantly associated with improved disease-free survival (DFS) (p 0.001) and showed a favorable trend toward improved overall survival (OS) (p = 0.056). No significant differences in survival outcomes were observed according to platinum exposure alone.Conclusion: Kaplan-Meier analysis suggested that achieving pCR is important for disease-free survival and that there is a positive trend toward improved overall survival in patients with triple-negative breast cancer. Although platinum-based chemotherapy did not confer a clear survival advantage, its association with higher pCR rates supports its use in the neoadjuvant setting, particularly in selected patients with biologically aggressive disease. These findings reinforce the prognostic value of pCR and highlight the importance of tumor biology in guiding neoadjuvant treatment strategies in triple-negative breast cancer.