Emerging tumor therapies and drugs such as targeted drugs and immunotherapy have resulted in a significant prolongation of the survival time of patients with many tumors such as breast cancer and lung cancer, as well as a significant increase in the occurrence of brain metastases. However, due to the drug resistance of tumor cells and the existence of the blood-brain barrier, it is difficult for drugs to reach the brain and work on the tumor cells in the brain, which makes most of the metastatic tumors in the brain poorly treated by drugs. For relatively small brain metastatic tumor lesions, or multiple brain metastatic tumor lesions, if medical treatments such as targeted immunotherapy are not effective, radiation therapy is an important option to choose, in addition to replacing the drug regimen with one that is more likely to pass the blood-brain barrier and enter the brain and be sensitive to tumor cells. Radiation therapy kills tumor cells that have metastasized to the brain through radiation and is an important treatment for brain metastases. Of course, depending on the number of metastatic lesions in the brain, stereotactic radiation therapy or whole brain radiation therapy can be chosen. However, for metastatic tumors with a large size in the brain, which have caused an increase in intracranial pressure, the patient’s condition is serious and the intracranial pressure needs to be lowered as soon as possible in order to have a chance to carry out other treatments and prolong the patient’s life. In this case, the effect of radiotherapy is greatly weakened, and it cannot completely kill the tumor cells in the large metastatic lesions. Moreover, the radioactive necrosis and edema caused by the tumor cells killed by radiotherapy will lead to further increase of intracranial pressure, and the symptoms such as headache will be further aggravated or even threatened to the patient’s life. In this case, surgical resection of metastatic lesions of relatively large size in the brain, especially single metastatic lesions would be valuable. On the one hand, surgical resection of metastatic tumor lesions can rapidly reduce the intracranial pressure, thus giving the opportunity to carry out other adjuvant treatments. In addition, genetic testing of surgically removed tumor specimens can help to further assist physicians in selecting potentially sensitive targeted or other anti-tumor agents. Of course, the treatment of metastatic tumor foci that have metastasized to the brain is a complex and dynamic process. During the course of metastatic tumor treatment, the size and number of metastatic tumor foci in the brain, as well as the patient’s general condition, and metastatic tumor foci in other parts of the body, are all dynamically changing. Determination of the treatment plan for brain metastatic lesions needs to be based on the size and number of brain metastatic lesions, as well as the control of tumors in other parts of the patient’s body and the overall physical condition, and reasonable selection of systemic chemotherapy or targeted therapy, radiotherapy, and surgical treatment plan.