Breast cancer metastasized to lungs can be treated with chemotherapy, targeted drug therapy, endocrine therapy and other comprehensive treatments according to the situation. 1. Chemotherapy: it is mainly used for further adjuvant treatment after surgery or unable to take surgical treatment, systemic chemotherapy can be carried out directly to control the progress of the disease and kill the tumor cells. 2. Targeted drug therapy: Trastuzumab, patuximab, etc. are commonly used in combination with chemotherapy, which can improve the quality of patients’ survival and prolong the survival period. 3. Endocrine therapy: for example, the use of toremifene, tamoxifen, etc., if necessary, can be combined with targeted drug therapy. Breast cancer metastasized to the lungs, control the development of the disease, need to actively cooperate with the doctor to take treatment, the patient can not use the drug arbitrarily.