Case Study: Ms. S is a 52-year-old woman who was diagnosed with infiltrating ductal breast carcinoma two years prior. She was treated with mastectomy followed by focal radiation and FAC (5-fluorouracil, adriamycin, and cyclophosphamide). One year ago, she began experiencing headaches. A magnetic resonance imaging scan with gadolinium revealed a 2 cm enhancing mass in the left temporal lobe, and she received whole-brain irradiation.