Low-grade
Low-grade tumors have cells that look similar to normal astrocytes. The cancer usually does not grow quickly or spread to other parts of the brain or the central nervous system. These tumors have a fairly favorable prognosis, especially if the doctor is able to completely remove the cancer with surgery. Tumors may appear in more than one spot in the cerebrum, especially when they are associated with neurofibromatosis.

High-grade
High-grade tumors have cells that do not look similar to normal astrocytes. These tumors grow quickly and can spread extensively to other parts of the brain. The cancer may spread outside the central nervous system, but this is rare. Younger children with high-grade tumors have a poor prognosis. Patients who have an anaplastic (malignant) astrocytoma that grows at a slower rate and who can have their tumors surgically removed may have a better prognosis.