Objective To systematically review the efficacy and safety of 3-month sustained releasing gonadotropin-releasing hormone agonist (GnRHa) (GnRHa 3M) and 1-month sustained releasing GnRHa (GnRHa 1M) in the treatment of pre-menopausal females with hormone receptor-positive breast cancer. Methods Databases including CNKI, WanFang Data, PubMed, EMbase and Web of Science were electronically searched to collect randomized controlled trials(RCTs) of GnRHa in the treatment of hormone receptor-positive breast cancer from inception to May 18th, 2021. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of the included studies. The gemtc software package in R 3.6.1 software and Stata 15.0 software were used for network meta-analysis. Results A total of 11 RCTs including 7 484 patients were included. The network meta-analysis results showed that there was no significant difference between GnRHa 3M and GnRHa 1M in E2 level (MD=?1.3, 95%CI ?13 to 9.6), DFS (HR=1.2, 95%CI 0.88 to 1.7) and OS (HR=2.0, 95%CI 0.75 to 4.9). For safety, there was no significant difference between the two groups (RR=1.0, 95%CI 0.25 to 4.2). Conclusion Current evidence shows that the efficacy and safety of GnRHa 3M is similar to that of GnRHa 1M. Due to the limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusions.
