Epidemiology of brain metastases

The incidence of intracerebral metastasis is largely underestimated. They a ppear to be the roost frequent cause of intracerebral tumors with an averag e incidence of probably more than 12/100 000 inhabitants per year. Dependin g on reports, 25 to 35 % of cancer patients will develop brain metastasis. In neurosurgical series, the frequency of cerebral metastasis among surgica l procedures far brain tumors increased from 3.5 to 12 %. We reviewed the l iterature in order to better know the frequency of intracerebral Metastasis depending on the type of primitive cancer. The rate of other metastatic le sions, the duration between discovery of the primitive cancer and brain met astatsis were found to be useful for selection of patients for neurosurgica l treatment. Three types of cancers could be defined, regarding the inciden ce of brain metastasis. While occurrence of brain metatstases is very high, surgery should often de useless; if brain metastases only occur in the lat e stage of a cancer, then, surgery should be discussed according to the gen eral status of the patient: although brain metastasis is rare in a cancer s urgery will often be required for diagnosis and treatment.