Oligodendroglioma

Overview

Oligodendroglioma is a kind of tumor found in central nervous system, typically impacting the brain, although it can rarely affect the spinal cord as well.

These tumors originate from a particular type of glial cell known as oligodendrocytes. Glial cells serve as the support system for your nervous system, ensuring the maintenance and protection of neurons responsible for transmitting and relaying signals within, to, and from your brain.

The grading system used by the World Health Organization (WHO) goes from grade 1 (lowest) to grade 4 (highest). This grading system identifies two main types of oligodendrogliomas:

• Oligodendrogliomas WHO grade 2: These oligodendrogliomas, also referred to as “low-grade oligodendrogliomas,” usually grow slowly. They also frequently response effectively to treatment.
• Oligodendrogliomas WHO grade 3: These are malignant oligodendrogliomas, also referred to as “high-grade oligodendrogliomas” (and previously known as “anaplastic oligodendrogliomas”). They are more aggressive type. They might be more difficult to treat and spread more quickly.

Surgery is often the treatment of choice when feasible. However, when a tumor is situated in a part of the brain that’s challenging for surgical tools to reach, performing surgery might not always be an option. In cases where surgery can’t be used to remove the tumor, or if there’s a high risk of the tumor recurring, other treatment options may be recommended.

Symptoms

Oligodendrogliomas, like many other types of brain tumors, often don’t present any symptoms until they begin to affect the surrounding brain tissue. The most frequent symptoms are headaches and seizures, with up to 80% of those affected by oligodendroglioma experiencing seizures. This high incidence of seizures is largely because oligodendrogliomas commonly involve the cerebral cortex. The cortex is a critical area where various functions essential for daily life, such as vision, language, motor skills, and more, are managed.

Besides seizures, oligodendrogliomas may cause specific localized symptoms, indicating a problem in a particular area of the brain. These symptoms usually affect a certain physical function or skill. Examples of such symptoms include:

• Aphasia, or difficulty speaking or understanding.
• Having difficulty focusing or thinking.
• Problem with memory.
• Hearing loss.
• Loss of vision, blurry or double vision.
• Weakness or paralysis of the muscles, particularly on one side of the body or face.

Causes

Oligodendrogliomas are by definition caused by two distinct genetic changes:

• 1p/19q co-deletion: Chromosomes are like compressed DNA “data,” serving as the instruction manual that your cells use to carry out various functions and processes. Chromosome copying mistakes can occasionally occur during cell reproduction. The long (q) arm of chromosome 19 and the short (p) arm of chromosome 1 are deleted in oligodendrogliomas. This is frequently referred to by experts as a “1p/19q co-deletion.”
• IDH1 or IDH2 mutation: Sections of your DNA data that carry particular instructions are called genes. One of them instructs your body on how to produce the enzyme isocitrate dehydrogenase (IDH), which is necessary for some forms of metabolism. IDH1 or IDH2 are two IDH mutations that can result in oligodendrogliomas.

All of the aforementioned genetic alterations are “de novo,” or “new.” This indicates that these deletions and mutations occur naturally. Neither of your biological parents gave them to you.

Risk factor

At present, there are no confirmed risk factors for developing oligodendroglioma. However, there is some evidence to suggest that previous radiation therapy, like that used in the treatment of different types of cancer, might contribute to the formation of gliomas, a group of tumors closely related to each other. Further research is necessary to establish whether something may serve as a causative or contributory factor in their development.