Exploring the Potential of Adjuvant CDK4/6 Inhibitors in Hormone Receptor-Positive Early Breast Cancer: A Consistent Approach for All

Abstract

Background/Objectives: Hormone receptor-positive, HER2-negative breast cancer is the most common subtype, with endocrine therapy as the standard treatment. Despite the advancements in adjuvant endocrine therapy, recurrence remains a challenge, particularly in high-risk patients. Recent trials on cyclin D kinase 4/6 (CDK4/6) inhibitors in adjuvant therapy have shown promise in reducing early recurrence and improving survival. Methods: This review analyzes the clinical evidence supporting the use of CDK4/6 inhibitors, focusing on the NATALEE and monarchE trials, which demonstrate comparable efficacy and manageable safety profiles for ribociclib and abemaciclib. Results and Conclusions: Ribociclib, with its broader applicability and impact on the decision making for axillary lymph node surgery, may be the preferred option in high-risk populations. The review also addresses unanswered clinical questions and highlights the need for ongoing research to optimize the adjuvant therapy strategies.