A central nervous system (CNS) glioma is a type of tumor that originates in the glial cells of the brain or spinal cord. Glial cells are supportive cells in the nervous system that surround and help neurons function. Gliomas are the most common type of primary brain tumor, meaning they start in the brain or spinal cord rather than spreading there from other parts of the body. Gliomas vary broadly in their behavior and include several types based on the type of glial cell involved:
- Astrocytomas, arising from astrocytes, which support neurons;
- Oligodendrogliomas, originating from oligodendrocytes, cells that produce the myelin sheath around nerve fibers;
- Ependymomas, developing from ependymal cells that line brain ventricles and the spinal cord canal.
Gliomas can be benign (low-grade) or malignant (high-grade), with some growing very slowly and others being very aggressive. They do not usually metastasize outside the CNS but can spread within the CNS through cerebrospinal fluid. Symptoms depend on the tumor's location and might include headaches, seizures, vision problems, weakness, or cognitive changes. Treatment typically involves surgery, radiation, and chemotherapy, depending on the type and grade of the glioma. In summary, a CNS glioma is a tumor formed from glial cells within the brain or spinal cord, ranging in severity from slow-growing to highly aggressive cancers.
