Diffuse astrocytoma is a type of brain tumor that is made up of cells called astrocytes. It is a low-grade tumor, meaning that it grows slowly and is less likely to spread to other parts of the body. Diffuse astrocytomas can occur in any part of the brain, but are most commonly found in the cerebrum. Symptoms of diffuse astrocytoma can include headaches, seizures, and changes in behavior or personality. Treatment typically involves surgery, radiation, and chemotherapy.