While this study provided comprehensive cost-effectiveness evidence about CDK4/6 inhibitors in the first-line use in HR+/HER2- advanced breast cancer, future research should go beyond traditional cost-effectiveness studies and delve into affordability, budget impact, market dynamics, and comparative effectiveness to provide a comprehensive understanding of the role and potential market uptake of CDK4/6 inhibitors in the treatment of advanced breast cancer. This evidence concerns the gene ERBB2 and breast cancer.