If there are less than three brain metastases, the addition of stereotactic radiotherapy (e.g., radio wave knife, X to, gamma knife) after whole brain radiotherapy may improve the survival rate, but if there are more than three lesions, the addition of stereotactic radiotherapy after whole brain radiotherapy generally will not significantly increase survival, but may prolong the time of lesion recurrence. Of course, if a large lesion causes clinical symptoms, the addition of stereotactic radiotherapy can be considered simply to control the symptoms caused by the local lesion for a longer period of time, but this will be analyzed on a case-by-case basis.