How long the leukemia spreads to the central nervous system can live depends on the complications, patient’s age, treatment effect, etc. Some patients have a survival period of less than one year, but there are patients who have survived for more than one year or for a longer period of time. 1. The spread of leukemia to the central nervous system can cause intracranial hypertension and meningeal irritation, etc. It can also damage the brain parenchyma, cranial nerves and spinal cord. If the patient develops intracranial hypertension, it can cause the patient’s death due to improper or untimely treatment. 2. If the patient is sensitive to drugs and the treatment effect is good, the survival time of the patient can be prolonged. 3. For patients with poor physical condition, insensitive effect and more complications, the survival period after CNS proliferation may be less than one year. For the above cases, the patient’s age, physique, condition, treatment method and effect, as well as the patient’s state of mind will affect the survival period of the patient. Therefore, it is not possible to accurately determine the length of patient survival.