There are about 130 different types of brain tumor. They are generally named after the type of cell they developed from. Most brain tumors develop from the cells that support the nerve cells of the brain called glial cells. A tumor of glial cells is a glioma.
Brain tumors can also be named after the area of the brain they are growing in. A tumor of the pituitary gland is called a pituitary adenoma. A tumor developed from the covering of the brain (the meninges) is called a meningioma. Tumors growing from the nerves entering the brain are called neuromas. A vestibular schwannoma (also sometimes called an acoustic neuroma) is a tumor growing on the nerve that controls balance and hearing.
Brain tumor grade – benign or malignant
Brain tumors are put into groups according to how quickly they are likely to grow. There are 4 groups, called grades 1 to 4. A pathologist examines the cells under a microscope. The more normal the cells look, the more slowly the brain tumor is likely to develop and the lower the grade. The more abnormal the cells look, the more quickly the brain tumor is likely to grow and the higher the grade. Low grade gliomas (grade 1 and grade 2) are the slowest growing brain tumors.
You may have been told you have a benign tumor or a malignant tumor. As a rule of thumb, low grade tumors are regarded as benign and high grade as malignant.
A benign tumor is not a malignant tumor, which is cancer. It does not invade nearby tissue or spread to other parts of the body the way cancer can. In most cases, the outlook with benign tumors is very good. But benign tumors can be serious if they press on vital structures such as blood vessels or nerves. Therefore, sometimes they require treatment and other times they do not.
- The tumor is relatively slow growing.
- It is less likely to come back if it is completely removed.
- It is not likely to spread to other parts of the brain or spinal cord.
- It may just need surgery and not radiotherapy or chemotherapy as well.
What causes a benign tumor to form? Often the cause is unknown. But the growth of a benign tumor might be linked to:
- Environmental toxins, such as exposure to radiation;
- Local trauma or injury;
- Inflammation or infection.
Malignancy tumor (cancer)
Cancer, also called malignancy, is an abnormal growth of cells. There are more than 100 types of cancer, including breast cancer, skin cancer, lung cancer, colon cancer, prostate cancer, and lymphoma. Symptoms vary depending on the type. Cancer treatment may include chemotherapy, radiation, and/or surgery.
- The tumor is relatively fast growing;
- It is likely to come back after surgery, even if completely removed;
- It may spread to other parts of the brain or spinal cord;
- It can’t just be treated with surgery and will need radiotherapy or chemotherapy to try to stop it from coming back or slow its growth.
Malignant tumors vary in size and shape. They grow in an uncontrolled, abnormal way and can grow into (invade) nearby tissues, blood vessels or lymphatic vessels. They can interfere with body functions and become life-threatening.
Cancer cells can break off and spread to distant locations in the body (metastasize). Cancer that spreads from its original location (the primary tumor) to a new part of the body is called metastatic cancer. Malignant tumors can also come back (recur) after they are removed.
Other types of tumor
With other types of cancer, these black and white explanations of benign and malignant often work well. But with brain tumors, there are a lot of grey areas. Some low grade astrocytomas can spread to other parts of the brain or spinal cord. Radiotherapy and chemotherapy are sometimes used to treat benign tumors. Even a slow growing tumor can cause serious symptoms and be life threatening if it is in an important part of the brain. So, it is important to ask your specialist to explain your own situation to you fully and simply.
Changing from benign to malignant
Some benign tumors can develop into a malignant tumor. It is called malignant transformation or progression to malignancy. For example a grade 2 tumor may change into a grade 3 tumor, and a grade 3 tumor into a grade 4.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Review Date: January 4, 2017 | Last Modified: January 4, 2017
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Cancer Health Center. http://www.webmd.com/cancer/default.htm. Accessed October 26, 2016.
Types of primary brain tumors. http://www.cancerresearchuk.org/about-cancer/type/brain-tumor/about/types-of-primary-brain-tumors. Accessed October 26, 2016.