Study to Evaluate the Efficacy and Safety of Temozolomide in Subjects With Brain Metastases of Either Malignant Melanoma, Breast, or Non-small Cell Lung Cancer (P02064)

Inclusion Criteria: * Cytological/histological diagnosis of either melanoma, non-small cell lung cancer and breast; * Brain metastases \>=1 cm presenting or in progression following \>=4 weeks time interval free from previous malignancy-specific chemotherapy, hormone therapy, or other medical therapies; * Magnetic resonance imaging suspected brain metastases; patients with brain lesion(s) not univocal as brain metastases must have negative radiolabeled leukocyte brain scan to rule out infectious non-malignant disease; all neuroradiological studies (baseline and treatment outcome evaluation), except for emergency exams must be performed after 10 days of unchanged schedule of dexamethasone, and obtained in the axial-coronal-sagittal planes in T1 and T2 before and after gadolinium enhancement. * Presence of al least one bidimensionally measurable and not previously irradiated metastasis. * Age \<=70 years. * Performance status 0-2 (ECOG-WHO scale). * Blood leukocytes \>=3.5 x 10\^9/L and platelets \>=100 x 10\^9/L. * Bilirubin \<=25 M/L. * Seric transaminases \<=2 x upper limit of normal values. * Creatinine \<=150 M/L, creatinine clearance \>=60 mL/min. * Signed written informed consent. Exclusion Criteria: * Diabetes not allowing administration of adequate doses of dexamethasone at least during the first 2 months of treatment. * Previous whole brain irradiation. * Brain metastases eligible to neurosurgery or stereotactic radiation therapy. * Previous or current malignancies at other sites with the exception of adequately treated in situ carcinoma of the cervix or basal and squamous carcinoma of the skin. * Pregnant or nursing women. * Acute infection requiring intravenous antibiotics. * Severe vomiting or medical condition which could interfere with oral medication intake. * Anticonvulsant chronic therapy.