For Ⅱ and Ⅲ stage breast cancers (BCs),neoadjuvant chemotherapy (NCT) is typically the initial treatment.However, there is no evidence to support an improvement in efficacy with dose-dense (DD) chemotherapy (CT) in this setting. Results from clinical trials of neoadjuvant DD-CT in patients with breast cancer are inconsistent.This systematic review evaluates whether DD-CT was more effective than the standard-schedule CT.
This meta analysis included all comparative prospective and retrospective studies published in Pubmed, Embase, the Cochrane Central Register of Controlled Trials, the Web of Science and the CNKI databases over the past 10 years.The studies that compared the DD-CT with a standard-schedule CT met our inclusion criteria.The primary outcomes were pathologic complete responses (ypT0N0M0: pCR). The secondary outcomes were disease-free survival (DFS) and overall survival (OS). Odds ratios (ORs) for pCR and Risk ratios (RRs) for DFS and OS were estimated and pooled.
Eight studies involving 2477 patients were included in this meta-analysis. Of these, 1214 patients were treated with DD-CT and 1263 patients were treated with CT. The primary outcomes included 8 studies while the secondary outcomes included 7 studies. The pooled rates of the pCR were 19.4% and 11.9% in the experimental and control arms respectively. A significant increase in the pCR [OR= 1.74, 95% confidence interval (CI) 1.38–2.18, P < 0.00001] was noted with DD-CT. Dose-dense treatment also improved DFS[RR= 0.78, 95%CI 0.63–0.98, P = 0.03] and OS [RR= 0.81, 95%CI 0.68–0.96, P = 0.01]. However there was some heterogeneity.Similar results were observed in the further analysis, which was supported by our sensitivity analyses.
The meta-analysis demonstrated that DD-NCT significantly increased the pCR of Ⅱ and Ⅲ stage breast cancer compared with standard-schedule CT. Adjuvant dose-dense regimens can also improve DFS and OS.Taking into account the actual improvement in clinical efficacy,prognostic valueand the acceptable safety profile, DD-CT can be considered a standard approach for neoadjuvant therapy in Ⅱ and Ⅲ stage breast cancer.
The Fourth Hospital of Hebei Medical University.
Has not received any funding.
All authors have declared no conflicts of interest.