 - 4-10 brain metastases, which are radiologically proven by MRI scan. The size of each metastasis must be between 3 mm and 4.0 cm in the largest diameter. Contrast-enhancements on MRI which are smaller than 3 mm in diameter are not considered. The total volume of the lesions must be smaller than 35 ml and the volume of perilesional normal brain receiving more than 4 Gy per fraction must be smaller than 40 ml. An evaluation of the latter criterion is strongly recommended for total lesions volume 20 ml prior to randomization of the patient according to figure 1. OR 