Radiotherapeutic Management of Brain Metastases from Breast Cancer

We have reviewed the medical records of 28 breast cancer patients with brainmetastases who were treated with radiotherapy at our clinic from 1980 through 1994(4 patients, postoperatively; 24 patients, radiotherapy alone). Radiotherapy was delivered as whole brain irradiation using lateral opposed 10 MV X-rays. Tenpatients received an additional boost to a reduced field. One patient was treated with localized stereotactic irradiation alone. The radiation dose for tumorsranged from 32 Gy to 60 Gy(mean, 49 Gy)in 2 or 3 Gy daily fractionated doses. The brain was the first site of metastatic involvement in only two patients. In the 26 evaluable patients, neurologic functional improvement was achieved in 24 patients(92%)with complete response(CR)in 12 patients(46%)and partial response(PR)in 12 patients(46%). The survival rates from the initial treatment were 39% at 5 years and 16% at 10 years(median survival time, 50 months), and those after treatment of brain metastases were 29% at one year and 18% at 2 years(median survival time, 6 months). Performance status tended to be associated with survival(p=0.10), and the presence of liver metastasis was the most important risk factor concerning survival(p=0.056). Two patients suffered severe chronic complications.One patient developed severe dementia after whole brain irradiation with a total dose of 45 Gy in 3 Gy daily fractionated dose, and another patient developed widespread brain necrosis after combined radiotherapy with intrathecal local infusion of methotrexate. Radiotherapeutic management is useful for breast cancer patients with brain metastasis, and long-term survival may also be possible even if patients have preexisting extracranial metastases, except for hepatic involvement. Radiation-related complications should therefore be avoided in these patients.