Brain metastases grow rapidly and can produce clinical symptoms within a short period of time, as they generally have a severe edema response and are relatively severe. The disease is progressively aggravated, and if there is degeneration, necrosis, hemorrhage, etc., the symptoms may be suddenly aggravated, and even brain hernia may occur, causing the patient to die in a short period of time. Symptoms of intracranial hypertension, such as headache and vomiting, are common, and about one-fourth of the patients may have epilepsy (seizures) and visual disturbances. Symptoms vary according to the location of the disease. Localized manifestations such as mental symptoms, visual disturbances, impaired movement or sensation of one limb, facial paralysis, and unfavorable speech may occur, or cerebrospinal fluid pathways may be blocked, resulting in hydrocephalus.