The life expectancy of an adult diagnosed with a low-grade brainstem glioma is between 4.9 and 7.3 years, claims PubMed Central. However, if the adult has the more aggressive form usually seen in children, the life expectancy is about a year.
In children, the survival rate for a brainstem glioma depends on its location, according to Cancer.net. If the tumor occurs in the medulla or midbrain, the survival rate after five years is between 65 and 90 percent. However, if the tumor is found in the pons, the child usually does not survive much more than a year. Fortunately, these tumors are rare and make up only 10 percent of all the brain tumors that affect children.