The value of platinum agents as neoadjuvant chemotherapy in triple-negative breast cancers: a systematic review and meta-analysis

Platinum agents such as cisplatin and carboplatin are DNA-damaging agents with activity in breast cancer (BC), particularly in the triple negative (TN) subgroup. The utility of platinum agents, in addition to standard neoadjuvant chemotherapy (NAC), is controversial. To assess the activity of platinum agents in patients with TNBC treated with NAC, we performed a systematic review and meta-analysis of all published studies. A search of PubMed, EMBASE, the Web of Science, SCOPUS, and the Cochrane Central Register of Controlled Trials was performed to identify studies that investigated platinum-based NAC in patients with TNBC. Random effect models were adopted to estimate the summary risk ratio (RR), and the publication bias was evaluated using a funnel plot and Egger's regression asymmetry test. The primary endpoints were the pooled rate of the pathologic complete response (pCR) and the RR to obtain a pCR in patients treated versus not treated with NAC containing platinum agents. 28 studies were included (six randomized controlled trials and 22 retrospective or prospective studies) for a total of 1,598 TNBC patients. Overall, the pooled rate of pCR in patients treated with platinum-based NAC was 45 %. In randomized trials, NAC containing cisplatin or carboplatin significantly increased the rate of pCR compared with nonplatinum agents (RR = 1.45, 95 % CI 1.25-1.68; P < 0.0001). Compared with non-TN, TNBCs were associated with a threefold increase in the pCR rate when treated with platinum-based NAC (RR 3.32, 95 % CI 2.39-4.61; P < 0.0001). In conclusion, pCR rates increase significantly with the addition of cisplatin or carboplatin in TNBC compared with NAC containing no platinum drugs. TN status is a predictor of benefit from platinum-based NAC.