We found that in patients with HER-2 overexpressed lung and breast cancers, chemotherapy combined with molecularly targeted therapy resulted in a survival benefit for patients with BMM, and in patients with HR positive, HER-2 negative breast cancers, CDK4/6 inhibitor with ET may be a better option for patients as its excellent great superiority due to its low toxicity and high efficiency. Here, CDK4 is linked to breast cancer.