Glioma

What is Glioma?

Glioma, also known as a Brain Tumor, refers to a tumor that develops in the brain or spinal cord. A glioma originates from glial cells that are present in the brain and spinal cord. Most of the tumors in the central nervous system are gliomas.

Is Glioma a Medical Emergency?

Glioma or a Brain Tumor is a medical emergency condition.

Types

Three types of glial cells produce these tumors. Classification is made depending on the type of glial cell present in the tumor and the genetic feature of the tumor. Types of glioma include:

• OligodendroGlioma: Tumor that occurs in the brain or spinal cord. They originate from the glial cells called oligodendrocytes. They primarily occur in adults. They also occur in children.
• Astrocytoma: This is a type of cancer that occurs in the brain or spinal cord. It begins in star-shaped glial cells called astrocytes that support the nerve cells in the brain. This type of brain tumor causes symptoms of nausea, headaches, and seizures.
• Glioblastoma multiforme (GBM): It is a grade IV fast-growing and aggressive brain tumor. It invades the nearby brain tissue but generally does not spread to distant organs.GBMs can arise in the brain de novo or evolve from lower-grade astrocytoma. In adults, GBM occurs most often in the cerebral hemispheres, especially in the frontal and temporal lobes of the brain. GBM is a devastating brain cancer that can result in death in six months or less, if untreated. hence, it is mandatory to take immediate medical care, as this can impact overall survival.

Classification of Gliomas

It is classified as low-grade glioma and high-grade glioma. Low-grade glioma grows slowly and in some cases can be removed completely with surgery whereas high-grade glioma is fast-growing, aggressive, and can spread easily.

OligodendroGlioma - IDH Mutant, 1p-19q codeleted

• WHO Grade 2
• Who Grade 3

Astrocytoma - IDH Mutant, 1p-19q non codeleted

• WHO Grade 2
• WHO Grade 3
• WHO Grade 4

Glioblastoma multiforme - IDH Wild type

• WHO Grade 4

Causes

The exact cause of glioma is not clear. However, genetic disorders such as neurofibromatosis or tuberous sclerosis can cause brain tumors. Radiation exposure can also play a vital role in the development of glioma. Other environmental factors like food and exposure to toxic chemicals are also a cause.

Risk Factors

Factors that increase the probability of developing brain tumors include:

• It is most common in individuals 45 to 65 years of age. Some of the types such as brainstem glioma  and pilocytic astrocytomas are more common in kids than in adults
• Having a previous history of radiation exposure during cancer treatment or exposure to atomic bombs can increase the risk of developing glioma
• Having a family history
• Having excessive consumption of alcohol, tobacco smoking, and illicit drugs
• Excessive usage of cell phones

Symptoms & Signs

Glioma can develop either in the brain or spinal cord. The function of the brain is affected depending upon the type and location of Glioma in the brain. Symptoms also vary depending on tumor size, location, and how rapidly it grows.

Symptoms include:

• Headache
• Nausea and vomiting
• Confusion
• Memory loss
• Difficulty with balance
• Seizures
• Vision problems like blurred vision, double vision, or loss of peripheral vision
• Irritability
• Speech problems

If it affects the spinal cord symptoms include:

• Pain in the neck, arm, back, and legs
• Fatigue
• Weakness and numbness in extremities
• Unsteady gait
• Loss of muscle control
• Loss of bowel or bladder control

Investigations

Investigation tests to diagnose glioma include:

• A neurological examination that includes testing of vision, hearing, balance, coordination, and reflexes
• Complete blood tests
• Imaging tests including MRI and CT scan. These tests help diagnose the size, type, and location of the tumor and help in designing a treatment plan

After diagnosing the tumor, the below tests are performed:

• A tumor biopsy is performed to determine the type of tumor and its grade. A needle is used to remove tissue of glioma that is hard to reach or in sensitive areas of the brain
• Tests to find the spread of cancer to other parts of the body like PET CT scan

All these tests are essential to determine the treatment plan.

Diagnosis

Diagnosis of Glioma is made by reviewing the signs and symptoms and considering the results of the investigation tests.

Treatment Options

Treatment depends on the type, size, location, grade of the tumor, and also age and general health condition of an individual.

Medical Treatment:

Medical treatment includes drugs that are prescribed to reduce signs and symptoms:

• Medications: Anti-epileptic medications are prescribed to control seizures. Steroids can be used to reduce swelling and pressure inside the brain.
• Chemotherapy: Chemotherapy is a drug used to kill and destroy fast-growing cancer cells. Chemotherapy is prescribed in the treatment of glioma. It is given either orally or through injections. It is given in combination with radiation therapy. The most common chemotherapy drug that is used is temozolomide.
• Targeted drug therapy: It is a type of therapy that focuses on particular abnormalities present in the cancer cells. By blocking these abnormalities, targeted drug therapy causes the cancer cells to die. One of the targeted drug therapy used to treat glioma is bevacizumab.

Surgery:

In the majority of cases, surgery is performed in the treatment of tumors. Surgical treatment depends upon the location of the tumor in the brain or spinal cord. The tumor can be removed completely or partially depending on its location. If the tumor is located in a region where complete resection is possible, then it is surgically excised. If the tumor is located near sensitive areas in the brain where resection would be risky and there would be possible damage to surrounding structures, partial resection of the tumor is done as much as possible and it is followed by radiation.

Removing a part of the glioma also decreases the severity of the symptoms immediately. Surgical resection can also be done with the help of intraoperative MRI and lasers. The neurosurgeon tries to protect as much of a healthy brain as possible. Awake brain surgery is also performed in the treatment of tumors. In this type of surgical procedure, the patient is asked to perform certain tasks during the operation to ensure the area of the brain controlling that function is not damaged.

Radiation Therapy :

Radiation therapy is essential in treating Glioma. It is usually given after surgical treatment. Radiation therapy is done using external beam radiation. It is a type of cancer treatment in which multiple high-energy beams of radiation such as X-rays or protons are focused on the tumor to kill the cancer cells. Different machines are used in the deliver radiation, including the Gamma Knife or linear accelerator (LINAC). Also, there are many advanced techniques of radiation delivery like IMRT, Rapid Arc, and IGRT technique.

Radiosurgery or stereotactic radiation therapy is a type of radiation where the tumor is treated with a high dose of radiation in less time. Proton beam therapy can be also used in the treatment of glioma. In this therapy, high-targeted doses of proton radiations are focused on the tumor minimizing exposure to the surrounding healthy tissue. Protons cause less damage to the surrounding structures than X-rays.

Role of Diet/ Exercise/ Lifestyle Changes/ Preventive Measures

After undergoing the treatment, a rehabilitation program is initiated. Rehabilitation is an important part of recovery after the treatment of glioma. A Brain Tumor affects many functions like vision, speech, thinking, and motor skills. Treatment of a brain tumor also makes the body weak. So rehabilitation is of utmost importance to gain back strength and to resume normal activities of life.

The rehabilitation program includes physical therapy, occupational therapy, and speech therapy. This program also improves an individual’s memory and thinking after recovering from a brain tumor. Even after the treatment, yearly follow-up is required with MRI scans.

Some of the lifestyle modifications include:

• Discontinue tobacco smoking
• Avoid or limit alcohol intake
• Avoid usage of the illicit drugs
• Regular exercises
• Maintaining a healthy weight
• Minimizing exposure to chemicals, sun rays or tanning beds, and pollution
• Minimizing the usage of cell phones

Complications

The following are the possible complications :

• Problems with coordination, muscle strength, speech, or eyesight
• Increased risk of developing other types of cancers
• Chances of recurrence
• Chances of progression of tumor
• Infection and bleeding from chemotherapy

Prognosis

The overall prognosis of glioma is poor. In the majority of the cases, the survival rate is 5 years after the treatment. However, it varies depending on several factors like the type of tumor, its location, the extent of its spread, age, and general health condition of the individual.

When to contact the doctor?/ How to identify complications?

Consultation is recommended after noticing the signs and symptoms of glioma.

Indications for hospitalization

Chemotherapy and radiation treatments can be performed in outpatient settings; however, surgical removal requires hospitalization. The length of the hospital stay depends upon the intensity of the surgery as well as the general health condition of an individual.

Suggested clinical specialists/ Departments to consult for this condition

• Neurosurgery
• Radiation Oncology