Brain metastases.

Brain metastases are frequent, accounting for 20% of all brain tumours. The most common primary tumours responsible for brain metastases are lung cancer in man and breast cancer in women. Most metastases are located at the grey matter-white matter junction, in junctional vascular territories and in the rolandic region. Although non-specific, MRI is the most sensitive neuroradiological method for the lesions, especially when accompanied by gadolinium injection. MRI must absolutely be performed before surgical treatment, as gadolinium might detect other metastatic lesions or show metastatic tumours so small that they were not visible at computerized tomography (CT).