Uncommon Brain Tumors - Types, Symptoms, Diagnosis, and Treatment

Introduction:

Tumors that arise from the brain and spinal cord are called primary tumors of the central nervous system. Primary brain tumors are rare, and they are identified by cell type. Most brain tumors are metastasized from other cancers from other parts of the body. The symptoms of the brain tumor vary depending on the site affected.

What Are Uncommon Brain Tumors?

The growth of abnormal cells in the brain is called a brain tumor. Brain tumors are divided into two categories- primary and secondary brain tumors. Primary brain tumors are tumors that generate inside the brain and can be both benign and malignant. In contrast, secondary tumors are the ones that spread or metastasize from different parts of the body to the brain, and they are malignant.

What Are the Types of Uncommon Brain Tumors?

Most primary brain tumors are gliomas that occur in the brain's supporting cells or the glial cells, which surround the nerve cell. It is a life-threatening tumor that can affect brain function based on the location and growth of the tumor. The other type of brain tumor is the non-glial tumor which arises from cells in the brain other than the glial cells like blood vessels, neurons, or glands.

What Are the Types of Gliomas?

The types of gliomas or the tumor that occur in the glial cells are -

• Astrocytomas - They are the most common primary tumor of the brain or the spinal cord. It can originate anywhere in the central nervous system. They are developed from astrocytes which are star-shaped cells.

• Ependymomas - It originates in the ependymal cells of the brain or spinal cord. Ependymomas of the brain are commonly found in young children. The symptoms include seizures and headaches.

• Glioblastomas - It is an aggressive tumor forming in the astrocytes (cells supporting nerve cells). The symptoms associated with glioblastoma are headaches, seizures, vomiting, etc.

• Medulloblastomas - It is common in children. It is seen in the cerebellum (the lower part of the brain involved in balance and coordination). It usually spreads through the CSF (cerebrospinal fluid).

• Oligodendrogliomas - It is formed from the cells in the central nervous system that protect the nerve cell called oligodendrocytes. Seizures and headaches are seen in oligodendrogliomas.

What Are the Types of Non-glial Tumors?

The types of non-glial tumors include -

• Meningioma - It is the common primary tumor of the brain, which is usually noncancerous. It originates from meninges. When cancer grows and compresses the brain and spinal cord, it results in many serious symptoms.

• The Pineal Gland and Pituitary Gland Tumors - These are the tumors that arise in the pineal and pituitary glands. It can cause seizures, headaches, vision changes, and memory loss.

• Primary CNS Lymphoma - It is a type of lymphoma that occurs in the lymphatic system of the central nervous system. It usually arises in the brain and can metastasize to the spinal fluid and eyes.

• Medulloblastoma - It occurs in the cerebellum. It spreads or metastases through cerebrospinal fluid.

• Craniopharyngioma - It is seen in the base of the brain near the pituitary gland. It is a benign tumor and is rare.

• Schwannoma - The tumors in the nerve lining or the nerve sheath is called a schwannoma. It is non-cancerous and seen in the vestibular nerve that controls balance.

What Are the Causes of Uncommon Brain Tumors?

The actual cause of the primary brain tumor is not clear. The cause of developing the brain tumor starts when there is an abnormal DNA (deoxyribose nucleic acid) mutation. The alteration in the DNA cause cells to divide and multiply rapidly to form an abnormal mass of cells or tissues called a tumor. People with a familial history of brain tumors and radiation exposure can have an increased risk of developing a brain tumor.

What Are the Symptoms of Uncommon Brain Tumors?

The signs and symptoms of rare brain tumors depend on the tumor's size, shape, location, and spread.

• Persistent headache.

• Nausea and vomiting.

• Blurring of the vision or double vision.

• Loss of peripheral vision.

• Numbness in hands or feet.

• Loss of sensation in the arm or leg.

• Imbalance.

• Speaking difficulty.

• Tiredness.

• Confusion and dizziness.

• Behavioral changes.

• Seizures.

• Hearing problems.

How Are Uncommon Brain Tumors Diagnosed?

Brain tumors are diagnosed by the following tests -

• Neurological Examination - Neurological examination checks hearing, vision, coordination to time, place, people, balance, and reflexes. This can help in assessing which part of the brain is affected.

• Magnetic Resonance Imaging (MRI) Scan - Using a large magnetic field, radiation, and computer technology, a three-dimensional image of the brain and affected region is produced.

• Computed Tomography (CT) Scan - Using a high amount of radiation and computer technology, cross-sectional images of the brain and affected organs are produced for diagnosis and treatment planning.

• Positron Emission Tomography (PET) - By using a radioactive drug, abnormal metabolic activities are identified.

• Biopsy - A small amount of tissue is removed from the tumor and is examined under the microscope to know the extent of the spread of the tumor.

What Is the Treatment for Uncommon Brain Tumors?

The treatment for brain tumors is based on the tumor's size, shape, extent of spread, and location.

• Surgical Therapy - Surgery depends on the location of the tumor. Complete surgical removal of tumors is done in small brain tumors, which do not metastasize to other areas and are easy to separate from adjacent tissues. Some brain tumors are located in sensitive areas, which makes it difficult to complete removal. In such cases, there will be remnants of cancerous cells left back. Removing a portion of tumor cells can decrease the signs and symptoms. Many risk factors are associated with the surgical removal of the tumor, like bleeding, infection, and nerve damage.

• Radiation Therapy - Radiation therapy uses a high amount of radiation to kill cancerous cells and reduce their growth of the cancerous cells. It can also shrink the tumor size before the surgical procedure. Radiation therapy can be done by two methods- external beam radiation and internal beam radiation. External beam radiation uses an outside source of radiation that is from a machine. In contrast, internal beam radiation or brachytherapy uses radiation seeds inserted into the body to deliver radiation to the specific sites needed. The side effects of radiotherapy depend on the dosage of radiation given.

• Radiosurgery - It focuses radiation on a particular site which is usually a small area, to kill the cancer cells by using multiple radiation beams. Each radiation beam will focus on a specific targeted area, resulting in an increased amount of radiation to that particular site, which helps kill the cancerous cells.

• Chemotherapy - By use of a high dosage of a drug to kill the cancerous tissues in the brain cells. It can be administered both orally and intravenously. Temozolomide is the most commonly used chemotherapy drug for a brain tumor. Using chemotherapeutic drugs can cause hair loss, nausea, and vomiting.

• Targeted Drug Therapy - Targeted drug therapy focuses on a specific site on the cancer cells by killing the cancer cells.

Conclusion:

The brain is a complex organ of the body. Tumors in the brain can result in difficulty in various aspects like speech, vision, memory, thinking ability, and motor skills. So after the surgical therapy, various rehabilitation is advised to live a normal life like physical therapy, occupational therapy, speech therapy, etc.