Efficacy of platinum-based and non-platinum-based drugs on triple-negative breast cancer: meta-analysis
Authors: Lin Canling , Cui Jiajun , Peng Zhen , Qian Kai , Wu Runwen , Cheng Yimin , Yin Weihua 
Published: October 2022

Abstract
Background
Triple-negative breast cancer (TNBC), the subtype of breast cancer with the highest mortality rate, shows clinical characteristics of high heterogeneity, aggressiveness, easy recurrence, and poor prognosis, which is due to lack of expression of estrogen, progesterone receptor and human epidermal growth factor receptor 2. Currently, neoadjuvant chemotherapy (NAT) is still the major clinical treatment for triple-negative breast cancer. Chemotherapy drugs can be divided into platinum and non-platinum according to the presence of metal platinum ions in the structure. However, which kind is more suitable for treating TNBC remains to be determined.

Methods
The relevant randomized clinical trials (RCTs) that explore the effectiveness of chemotherapy regimens containing platinum-based drugs (PB) or platinum-free drugs (PF) in treating TNBC patients were retrieved through PubMed, EMBASE, Cochrane Library, CNKI, and other literature platforms, above research findings, were included in the meta-analysis. The incidence of overall remission rate (ORR), pathological complete remission rate (pCR), overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and adverse events (AE) were compared between the two groups.

Results
In this study, 12 clinical trials with a total of 4580 patients were included in the analysis. First, the ORR in 4 RCTs was, PB vs PF = 52% vs 48% (RR = 1.05, 95% CI: 0.91–1.21, P = 0.48); the pCR in 5 RCTs was, PB vs PF = 48% vs 41% (RR = 1.38, 95% CI: 0.88–2.16, P = 0.17). CI: 0.88–2.16, P = 0.17; the other 2 RCTs reported significantly higher DFS and OS rates in the PB group compared with the PF group, with the combined risk ratio for DFS in the PB group RR = 0.22 (95% CI:0.06–0.82, P = 0.015); the combined risk ratio for DFS in the PF group RR = 0.15 (95% CI. 0.04–0.61, P = 0.008); OS rate: PB vs PF = 0.046 vs 0.003; secondly, 2 RCTs showed that for patients with BRCA-mutated TNBC, the pCR rate in the PB and PF groups was 18% vs 26%, 95% CI: 2.4–4.2 vs 4.1–5.1; meanwhile, the median subject in the PB group The median PFS was 3.1 months (95% CI: 2.4–4.2) in the PB group and 4.4 months (95% CI: 4.1–5.1) in the PC group; finally, the results of the clinical adverse effects analysis showed that platinum-containing chemotherapy regimens significantly increased the incidence of adverse effects such as thrombocytopenia and diarrhea compared with non-platinum regimens, while the incidence of adverse effects such as vomiting, nausea, and neutropenia was reduced. The incidence of adverse reactions was reduced.

Conclusion
Compared with non-platinum drugs, platinum drugs significantly improved clinical treatment effective indexes, such as PCR, ORR, PFS, DFS, and OS rate in the treatment of TNBC patients without BRCA mutant may cause more serious hematological adverse reactions. Accordingly, platinum-based chemotherapy should be provided for TNBC patients according to the patient's special details.