Brain Tumors in Children

What are brain tumors in children?

A brain tumor is an abnormal growth of tissue in the brain. The brain is part of the central nervous system (CNS). The CNS also includes the spinal cord. The main parts of the brain are:

• Cerebrum: The cerebrum sits in the front of the brain and is made up of 2 halves, the right and left hemispheres. This controls thoughts, emotions, speech and movement. The cerebrum also helps with understanding information from the senses like seeing, hearing, smelling, touching and pain.
• Cerebellum: The cerebellum is located towards the back of the brain and organizes muscle movement. This helps maintain posture, balance and equilibrium.
• Brainstem: The brainstem is located towards the back of the brain. This part of the brain connects to the spinal cord and controls muscles and sensations from the body. Part of the brainstem helps control breathing and heartbeat. Many of the cranial nerves start in the brainstem. The cranial nerves carry messages between different parts of the upper body to the brain including the muscles in the face, mouth and around the eyes.

Brain tumors can be found throughout these parts and start in the cells of the brain. They can be benign or malignant:

• Benign: This kind of tumor is non-cancerous. In most cases, once a benign tumor is removed, it doesn’t grow back. Most benign brain tumors don’t grow into nearby tissue. These tumors can cause symptoms depending on how big they are and where they are located in the brain.
• Malignant: A malignant tumor is cancerous. These brain tumors grow fast and can grow into nearby tissue. This type can also spread to other parts of the brain and/or to the spinal cord. However, they may grow back after treatment.

Brain tumors can grow at any time, no matter the age. However, brain tumors are very different in infants and children than adults.

Types of Brain Tumors

There are different types of brain tumors. Here are some of the different types of tumors that can affect children:

• Astrocytoma begins in the glial cells and is one of the more common brain tumors in children. It can develop anywhere in the brain or spinal cord. Astrocytomas are graded by the WHO scale from I to IV (I being the most benign, and IV being the most malignant).
• Medulloblastoma usually grows near the cerebellum and can sometimes block the flow of cerebrospinal fluid (CSF), causing pressure in the brain. Treatment usually involves surgery, followed by chemotherapy and/or radiation treatment.
• Ependymoma usually grows in the lining of the ventricles that hold CSF, or the spinal cord. These tumors are most often near the cerebellum and can cause increased pressure in the brain or brainstem. Treatment usually involves surgery and/or radiation treatment.
• Brain stem glioma is found in the brain stem. Tumors inside the brain stem often cannot be removed with surgery.
• Oligodendroglioma grows from cells called oligodendrocytes. These cells make up the covering of nerve cells. This type of tumor usually grows slowly.
• Optic nerve glioma is found on or around the nerves that send messages from the eyes to the brain, which can affect vision.

Here are other types of brain tumors that are less common:

• Embryonal tumors start in the cerebellum and tend to grow and spread quickly.
• Craniopharyngioma is a benign tumor that starts near the pituitary gland. It usually grows slowly. Although this tumor is not cancerous, it can grow near important structures that control vision and hormone production, and this tumor can cause vision loss if it is pressing on the optic nerves.
• Mixed glial and neuronal tumors are made up of glial and nerve cells and grow slowly. They are found in the cerebrum.
• Choroid plexus tumor is a rare and benign tumor that starts in the ventricles of the brain.
• Schwannoma begins growing in myelin-making cells that cover nerves. One type of schwannoma is a vestibular schwannoma, or acoustic neuroma, and it affects the nerve in the inner ear that helps with balance. It is usually a benign tumor.

What causes brain tumors in children?

Healthcare providers have yet to discover what causes brain tumors and why certain children develop brain tumors.

What are the symptoms of brain tumors in children?

Brain tumor symptoms can vary in children depending on the tumor size, growth rate and location. Growing tumors can cause increased pressure on the brain in the small space inside the skull, called increased intracranial pressure (ICP).

Symptoms of brain tumors can include:

• Seizures
• Headaches
• Enlarged head in infants
• Nausea and vomiting
• Sleepiness
• Troubles with vision, hearing or speech
• Weakness or paralysis in part of the body (often 1 side)
• Clumsy movements of the hands, arms, feet or legs
• Balance problems
• Muscle stiffness
• Mood changes
• Difficulty swallowing
• Problems with walking (ataxia)
• Bowel or bladder problems

Symptoms of brain tumors can be similar to many other health conditions. Make sure your child sees a doctor for a diagnosis.

How are brain tumors diagnosed in children?

There are various exams in which a brain tumor is diagnosed. Your child’s doctor will ask about your child’s health history and symptoms. A neurological exam will be conducted testing reflexes, muscle strength, coordination, and eye and mouth movement. Upon examination, your doctor may refer your child to a neurologist, neurosurgeon or oncologist (cancer specialist). Some tests that can be done are:

• MRI: An MRI (magnetic resonance imaging) takes a detailed picture of the brain using magnetic technology (no radiation). It can show the tumor more clearly. Contrast dye may be injected via an IV to help identify the tumor.
• CT scan: A CT scan uses multiple x-rays to take a picture of the brain. It is generally faster than an MRI and can be used if an MRI cannot be done.
• Lumbar puncture: This is a procedure in which a needle is placed into the spinal canal in the lower back. The spinal canal is the area around the spinal cord. Using the needle, a small amount of CSF is removed and sent for testing. The CSF can be tested for cancer cells.
• Positron emission tomography (PET) scan: In a PET scan, radioactive sugar is put into the bloodstream. Cancer cells use more sugar than normal cells, so the sugar will collect in cancer cells. A special camera is then used to see where the radioactive sugar collects in the body. A PET scan can sometimes find cancer cells in other parts of the body, even when they don’t show up on other tests. A PET scan is often used in combination with a CT scan. This is called a PET/CT scan.
• Biopsy: A biopsy is a type of surgery in which a piece of the tumor is removed and sent to the lab for testing. A biopsy is conducted to find out the type of tumor and how quickly it’s likely to grow.
• Blood tests: Blood tests can be done to check for substances that are released by some tumors. These are called tumor markers.

These tests will show where and how much cancer there is in your child’s body. These results will help decide how best to treat the cancer and the different outcomes to expect.

When determining treatment and predicting outcomes, doctors will look at things like:

• Type of tumor
• Location and size of the tumor
• Where cancer has spread in the body
• How the tumor is affecting your child
• Your child’s age
• Whether the tumor can be removed with surgery

Doctors will also consider the grade of the cancer cells, meaning a measure of how quickly the cells are likely to grow and spread. It is based on how much the cancer cells look like normal cells. High-grade cancer cells look very different from normal cells and are more likely to grow and spread faster.

How are brain tumors treated in children?

Brain tumors in children are rare, so it’s important to find a healthcare team that has experience and skill in treating children with brain tumors. Treatment can include one or more of the following methods:

• Surgery: Surgery is often the first step in treating brain tumors. The goal of surgery is to remove as much of the tumor as safely possible.
• Chemotherapy: Chemotherapy is  strong medicine that kills cancer cells or can stop them from growing.
• Targeted therapy: These are medicines that identify and attack specific parts of cancer cells with the potential of less harm to normal cells.
• Radiation therapy: Radiation uses high energy x-rays or other types of radiation to kill cancer cells or stop their growth.

With any cancer, a child’s expected recovery will vary. Keep in mind:

• Getting medical treatment right away is important for the best outcomes.
• Ongoing follow-up care during and after treatment is needed.
• New treatments are being tested to improve outcomes and to lessen side effects.

Types of Brain Tumor Surgeries

A craniotomy is a surgical procedure in which an incision is made in the scalp over the location of the brain tumor. During this surgery, a part of the skull is removed, and the covering of the brain (dura) is opened to get to the tumor. Once the tumor is reached, the surgeon carefully removes as much of the tumor as possible.  Once that is done, the dura is stitched back together, and the the skull is put back in place. The wound is then closed with staples or stitches.

An endoscopic brain surgery is a minimally invasive brain surgery, that allows doctors to get an in-depth view of the brain without using large incisions. Endoscopes are thin tubes that act as a camera and are inserted via small openings in the skull. Once inserted, the cameras transmit images of the brain and the tumor. Using the endoscope to see the tumor, doctors can remove the tumor using surgical instruments.

Laser Ablation (LITT)

Laser interstitial thermal therapy (LITT) or laser ablation is the latest advancement in minimally invasive neurosurgery. This helps surgeons target tumors and reach difficult areas of the brain with less risk to patients.

In laser ablation surgery, a probe is placed through a small hole in the skull using MRI visualization.   A robot is often used to assist with placement of the probe.   A laser is then is used through the probe to deliver heat to the targeted area. This destroys the abnormal tissue and is very useful for patients that have deep tumors.

Patients who do laser ablation experience less blood loss, pain, and side effects overall. Compared to a craniotomy procedure, laser ablation can be a significantly shorter hospital stay and recovery time.

CHOC is at the forefront utilizing this technology and has expanded to using robotic stereotactic assistance to increase surgical precision when operating on the brain.

What are possible complications of a brain tumor?

A child can have complications from the tumor, such as:

• Damage to the brain or nervous system that causes problems with coordination, muscle strength, speech, or eyesight
• Problems after surgery, like infection, bleeding, and problems with general anesthesia
• Delayed growth and development
• Learning problems
• Problems with reproduction (infertility)
• Return of the cancer
• Growth of other cancers in the future

How can I help my child live with a brain tumor?

Helping your child live with a brain tumor can be difficult. A child with a brain tumor needs ongoing care and will continue to be seen by oncologists and other health providers to treat any late effects of treatment or signs of the tumor returning.

You can help your child manage treatment in many ways, such as:

• Getting emotional support for your child. Going through cancer is taxing, mentally and physically, especially for a young person. A counselor, psychologist, or child support group can help.
• Encourage your child to get exercise, which can be beneficial to overall health.
• Your child may have trouble eating; a dietitian may be able to help.
• Your child may need physical therapy to help with movement and muscle strength.
• Make sure your child attends all follow-up appointments.

Clinical Trials in Neuro-oncology

Clinical trials are research studies that are used to provide the latest treatments to patients.

All clinical trials are conducted through the Hyundai Cancer Institute at CHOC. CHOC is a member of the Children’s Oncology Group (COG), which is a large consortium of hospitals and research institutions dedicated to finding new treatments for children’s cancers. This allows CHOC to collaborate with institutions around the country to deliver the latest treatments to our patients. The Hyundai Cancer Institute has received a Phase 1 clinical trial designation, allowing CHOC patients to receive the latest research-based treatments.

For more information on participation in brain tumor clinical trials, contact the CHOC Research Institute at 714-509-4341.

Brain conditions in children can be complex and require a team of caregivers, with each caregiver bringing a special expertise. At CHOC, a multidisciplinary approach allows us to offer our patients virtually all the services they need under one roof.

Learn more about the treatments and neuro-oncology programs offered at Hyundai Cancer Institute and CHOC Neuroscience Institute.