Effectiveness comparison of first-line CDK4/6 inhibitors in patients with hormone-positive HER2-negative advanced breast cancer according to tumor histology: a sub-analysis of the real-world, multicenter, Italian study PALMARES-2

Tumor histology affects the real-world effectiveness of first line ET plus CDK4/6i. In ILC, all three CDK4/6i performed similarly; therefore, treatment selection should prioritize tolerability, manageability, drug-drug interactions, and patient preferences.