[Early diagnosis of metastatic brain tumor]

For the early diagnosis of metastatic brain tumor, careful and long-term follow-up is important when the primary tumor has already been found. Metastatic brain tumor should be suspected whenever neurological symptoms develop in such a patient. In the cases of lung cancer or lung metastases, CT scan of brain should be taken even if the patients have no neurological symptoms, because lung cancer frequently metastasizes to the brain and other cancers metastasize to the brain via the lung. When the primary sites are unknown, primary brain tumors should be distinguished. Relatively rapid progression of symptoms including mental disturbance, multiple lesions on CT scan, lesions on chest X ray film, careful cerebral angiogram and MRI are helpful for the differential diagnosis.