The Anaplastic astrocytoma is defined as an uncommon cancerous tumour in the brain. These tumours form from several brain cells that are shaped as a star and are known as astrocytes. Cells like astrocytes develop the tissue that nears and shields other nerve cells that are present in the spinal cord and the brain. Together, all these cells are called glial cells, and the glial tissue is the tissue that they develop. Astrocytomas are one of the tumors that come from glial tissues and known as gliomas. Anaplastic astrocytoma is a kind of brain cancer. This disease comes in the class of high-grade gliomas that are persistently analogous gliomas and that take an improper clinical prediction. This disease also lacks vascular multiplication.

The tumours that are caused in this disease, comprise of cells that are both normal and abnormal. The two kind of astrocytomas are; low-grade astrocytomas and high-grade astrocytomas. The astrocytomas that have a tendency to grow slow are low-grade astrocytomas, whereas the ones which have a tendency to grow at a high pace are high-grade astrocytomas.