Platinum-based neoadjuvant chemotherapy in triple-negative breast cancer: a systematic review and meta-analysis

Background: The role of platinum-based neoadjuvant chemotherapy in triple-negative breast cancer (TNBC) patients is highly controversial and it is not endorsed by current guidelines. Our meta-analysis aimed to better elucidate its activity, efficacy and safety. Material and methods: A systematic search of Medline, Web of Science and conferences proceedings up to 30 October 2017 was carried out to identify randomized controlled trials (RCTs) investigating platinum-based versus platinum-free neoadjuvant chemotherapy in TNBC patients. Using the fixed and random effects models, pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CI) were calculated for pathological complete response (pCR, defined as ypT0/is pN0), event-free survival (EFS), overall survival (OS) and grade 3 and 4 adverse events (AEs: neutropenia, anemia, thrombocytopenia and neuropathy). Results: Nine RCTs (N = 2109) were included. Overall, platinum-based neoadjuvant chemotherapy significantly increased pCR rate from 37.0% to 52.1% (OR 1.96, 95% CI 1.46-2.62, P < 0.001). Platinum-based neoadjuvant chemotherapy remained significantly associated with increased pCR rate also after restricting the analysis to the three RCTs (N = 611) that used the same standard regimen in both groups of weekly paclitaxel (with or without carboplatin) followed by anthracycline and cyclophosphamide (OR 2.53, 95% CI 1.37-4.66, P = 0.003). Conversely, among the 96 BRCA-mutated patients included in two RCTs, the addition of carboplatin was not associated with significantly increased pCR rate (OR 1.17, 95% CI 0.51-2.67, P = 0.711). Two RCTs (N = 748) reported survival outcomes: no significant difference in EFS (HR 0.72, 95% CI 0.49-1.06, P = 0.094) and OS (HR 0.86, 95% CI 0.46-1.63, P = 0.651) was observed. A significant higher risk of grade 3 and 4 hematological AEs, with no increased risk of grade 3 and 4 neuropathy was observed with platinum-based neoadjuvant chemotherapy. Conclusion: In TNBC patients, platinum-based neoadjuvant chemotherapy is associated with significantly increased pCR rates at the cost of worse hematological toxicities. Platinum-based neoadjuvant chemotherapy may be considered an option in TNBC patients. PROSPERO registration number: CRD42018080042.