Multicenter Real-World Evaluation of Neoadjuvant Carboplatin in Triple-Negative Breast Cancer

Abstract

Background: The role of carboplatin in neoadjuvant chemotherapy for triple-negative breast cancer (TNBC) remains controversial, particularly in settings where access to immunotherapy is limited. This study evaluated the real-world impact of adding carboplatin to neoadjuvant chemotherapy on pathological complete response (pCR) and survival outcomes in patients with TNBC.

Methods: This retrospective multicenter study included patients with nonmetastatic TNBC treated with neoadjuvant anthracycline- and taxane-based chemotherapy between 2018 and 2023 at three oncology centers in Turkey. Patients were grouped according to receipt of platinum-containing therapy. Survival outcomes were estimated using the Kaplan-Meier method and compared with the log-rank test. Cox regression analyses were performed to evaluate factors associated with survival. Propensity score matching was also performed as a supportive analysis.

Results: A total of 142 patients were included, of whom 45 (32.2%) received platinum-containing neoadjuvant chemotherapy. Overall, 80 patients (56.3%) achieved pCR. The pCR rate was significantly higher in the platinum group than in the non-platinum group (68.9% vs. 50.5%, p = 0.031). After a median follow-up of 57 months, 24 deaths and 33 DFS events were observed. Median OS and DFS were not reached. The 60-month OS rate was 96.0% in the platinum group and 73.9% in the non-platinum group (log-rank p = 0.027), whereas the 60-month DFS rates were 86.1% and 67.6%, respectively (log-rank p = 0.139). Patients who achieved pCR had significantly better OS and DFS than those with residual disease. In the propensity score-matched cohort, non-platinum treatment remained associated with inferior OS and DFS.

Conclusions: In this multicenter real-world cohort, carboplatin was associated with a higher pCR rate and numerically favorable survival outcomes. These findings may be clinically relevant where immunotherapy is not readily accessible but should be considered hypothesis-generating and require prospective validation.

Keywords: carboplatin; neoadjuvant chemotherapy; overall survival; pathological complete response; triple‐negative breast cancer.