CDK4/6 inhibitors in advanced hormone receptor-positive/HER2-negative breast cancer: a systematic review and meta-analysis of randomized trials.

Combining CDK4/6 inhibitors and endocrine therapy (ET) improved outcomes for the treatment of metastatic HR+/HER2- breast cancers. Here, we performed a meta-analysis of randomized clinical trials (RCTs) to better define the benefit and the risk of CDK4/6 inhibitors plus ET for endocrine-sensitive or endocrine-resistant population in metastatic HR+/HER2- breast cancer.