Sequential Vs Concurrent Adjuvant Chemotherapy for Operable Breast Cancer: A Meta-analysis

Abstract Backgroud: Controversy still remains in that whether sequential or concurrent regimen of anthracyclines and taxanes benefits more for breast cancer. Here we aimed to compare these two regimens in patients with operable breast cancer based on all published data of phase III randomized controlled trials in this topic.Methods: A literature search on PubMed, Web of science, Embase, ScienceDirect, Google scholar and clinicaltrials.gov databases was conducted up to May 2020. Meta-analysis was performed to evaluate the different efficacy on disease free survival (DFS) and overall survival (OS)for these two regimens. Subgroup analyses were further carried out in terms of node status and anthracycline selection.Results: Compared to concurrent regimen, sequential regimen did not improve the DFS or OS in the whole population included. Subgroup analysis showed that in node-positive patients, however, sequential regimen has better DFS, but not OS, than concurrent regimen.In sequential regimen, patients received doxorubicin and taxanes had improved DFS and OS than those were given epirubicin and taxanes. Futhermore, for patients receiving doxorubicin and taxanes,compared to sequential regimen,less cycles (4 cycles) of concurrent treatment showed worse DFS and OS, whereas more cycles(6 cycles) may rescue the loss.In addition,high grade toxicity response in both groups exhibited no difference except for neuropathy, which occured more frequently in the sequential regimen.Conclusions:Sequential regimen of anthracyclines and taxanes for patients with breast cancer did not promise a significant benefit in neither DFS nor OS over concurrent regimen. However, sequential regimen did provide a better DFS than that in concurrent regimen for node-positive patients. Interestingly, further subgroup analysis showed that for patients with node-positive and were given doxorubicin and taxanes, more cycles (6 cycles) of concurrent reigmen was not inferior to sequential regimen.