Stereotactic Radiosurgery vs Whole Brain Radiotherapy in Breast Cancer With Brain Oligometastasis

All patients to undergo planning CT simulation with 1mm slice thickness. For all lesions, the gross tumor volume (GTV) will be defined as the visible tumor on CT and/or MRI imaging. A Planning Target Volume (PTV) margin of 2-5 mm will be added. Organs at risk visible in the planning CT scan will be contoured. The doses will be prescribed to approximately 100% isodose level and 95% of the PTV should receive 95% of the prescription dose. Metastases with a maximum diameter of up to 2 cm will be treated with doses of 22 to 25 Gy and those larger than 2 cm will be treated with doses of 18 to 20 Gy.