CDK4/6 inhibitors improved iDFS (HR 0.80; 95% CI: 0.67–0.96; p = 0.01), while a strong trend toward improved DRFS was observed (HR 0.79; 95% CI: 0.61–1.02; p = 0.07), suggesting a potential clinically relevant benefit that requires longer follow-up to confirm.
The key outcomes of this meta-analysis indicate that CDK4/6 inhibitors significantly improve iDFS, while a clear trend toward benefit is also observed in DRFS, suggesting a potentially clinically meaningful effect that has not yet reached statistical significance.
Conclusions: The addition of CDK4/6i to ET improves iDFS and shows a favorable trend in DRFS in early-stage HR+/HER2− breast cancer, highlighting the need for longer follow-up to clarify their long-term benefit. early-stage HR+/HER2− breast cancer CDK4/6 inhibitors endocrine therapy adjuvant therapy meta-analysis invasive disease-free survival abemaciclib ribociclib palbociclib Thi