Pediatric Brain CancerIf your child has a brain or spinal cord tumor, knowing what to expect can help you cope.
Brain and spinal cord tumors are masses of abnormal cells in the brain or spinal cord that have grown out of control.
Brain tumors rarely spread to other parts of the body, though many of them are considered malignant because they can spread through the brain and spinal cord tissue. But even so-called benign tumors can press on and destroy normal brain tissue as they grow, which can lead to serious or sometimes even life-threatening damage. Because the difference between benign and malignant tumors isn’t as important in the brain, doctors usually speak of “brain tumors” rather than “brain cancers.”
Several factors are important when doctors are trying to figure out how best to treat a tumor and what the prognosis is likely to be.
The type of tumor: Tumors can form in almost any type of tissue or cell in the brain or spinal cord. Some tumors have a mix of cell types.
The grade of the tumor: Some brain and spinal cord tumors are more likely to grow into nearby tissues than others.
Gene changes in the tumor cells: Even for a specific type of tumor, the changes in the genes of the tumor cells can be different.
The location of the tumor: Where the tumor is in the brain, and spinal cord can affect what symptoms it causes and which treatments might be best.
The cause of most brain and spinal cord tumors is not fully understood, and there are very few known risk factors for these tumors. But researchers have found some changes that occur in normal brain cells that may lead them to form tumors.
Normal human cells grow and function based mainly on the information in each cell’s DNA. Brain and spinal cord tumors, like other tumors, are usually caused by changes (mutations) in the DNA inside cells. DNA is the chemical that makes up our genes, which control how our cells function. We usually look like our parents because they are the source of our DNA. But DNA affects more than how we look.
Some genes control when our cells grow, divide into new cells, and die:
- Certain genes that help cells grow, divide, and stay alive are called oncogenes.
- Genes that help keep cell division under control, or cause cells to die at the right time, are called tumor suppressor genes.
Cancers can be caused by DNA changes that turn on oncogenes or turn off tumor suppressor genes. These gene changes can be inherited from a parent (as is sometimes the case with childhood cancers), but more often, they are acquired during a person’s lifetime.
For most types of cancer, the stage – a measure of how far the cancer has spread – is one of the most important factors in selecting treatment options and determining a person’s outlook (prognosis).
But brain and spinal cord tumors differ in some important ways from cancers in other parts of the body. One of the main reasons other types of cancer are dangerous is that they can spread throughout the body. Tumors starting in the brain or spinal cord can spread to other parts of the central nervous system but rarely spread to other organs. These tumors are dangerous because, as they grow, they can interfere with essential functions of the brain.
Because most brain or spinal cord tumors do not usually spread, they do not have a formal staging system like most other types of cancer.
Tumors in any part of the brain might raise the pressure inside the skull (known as intracranial pressure). This can be caused by tumor growth, brain swelling, or blocked the flow of cerebrospinal fluid. Increased pressure can lead to general symptoms such as:
- Crossed eyes or blurred vision
- Balance problems
- Behavior changes
- Drowsiness or even coma
Headaches that get worse over time are a common symptom of brain tumors. But not all brain tumors cause headaches, and tumors do not cause most headaches.
In some children, seizures are the first symptom of a brain tumor. Brain tumors do not cause most seizures in children. Still, if your child has a seizure, your child’s doctor may refer you to a neurologist (a doctor who specializes in brain and nervous system problems) to ensure it wasn’t caused by a brain tumor or other serious disease.
In the first few years of life, other symptoms of tumors can include:
- Loss of appetite
- Developmental delays
- Drop-in intellectual and physical abilities
- Increased head size, sometimes along with bulging of the soft spots of the skull (fontanelles)
Other general symptoms of tumors can include poor school performance, fatigue, and personality changes in the school-aged child.
If the child can cooperate, the doctor can sometimes tell if the pressure inside the skull is increased by looking inside the child’s eyes for swelling of the optic nerve (known as papilledema).
The main treatments for children with brain and spinal cord tumors are:
- Radiation Therapy
- Targeted Therapy Drugs
- Drugs to Help with Symptoms
In many cases children will get some combination of these treatments. Treatment is based on the type of tumor and other factors. Doctors plan each child’s treatment individually to give them the best chance of a cure while limiting side effects as much as possible.
The treatment options for brain and spinal cord tumors depend on many factors, including:
- The type of tumor
- The location of the tumor
- How far the tumor has grown or spread
- The child’s age and overall health
MRI scans are very good for looking at the brain and spinal cord and are considered the best way to look for tumors in these areas. MRI images are usually more detailed than those from CT scans (described below). But they don’t show the bones of the skull as well as CT scans and therefore might not show the effects of tumors on the skull.
MRI scans use radio waves and strong magnets (instead of x-rays) to make pictures, so they don’t expose the child to radiation. A contrast material called gadolinium may be injected into a vein before the scan to help see details better.
MRI scans can take a long time, and require a person to stay still for several minutes at a time. Some children might need medicine to help them relax or even go to sleep during the test.
The CT scan uses x-rays to make detailed cross-sectional images of your child’s brain and spinal cord. Unlike a regular x-ray, a CT scan creates detailed images of the soft tissues in the body.
For brain and spinal cord tumors, CT scans are not used as often as MRI scans, which give slightly more detailed images and do not use radiation. Still, there are instances where CT scans may have advantages over MRI scans:
- CT scans take much less time than MRIs, which can be particularly helpful for children who have trouble staying still.
- CT scans provide greater detail of the bone structures near the tumor than MRIs do.
- CT angiography (CTA), described below, can provide better details of the blood vessels in and around a tumor than MRA in some cases.
For a PET scan, a radioactive substance (usually a type of sugar known as FDG) is injected into the blood. The amount of radioactivity used is very low and passes out of the body within a day or so. Because tumor cells in the body are growing quickly, they absorb larger amounts of the sugar than most other cells. A special camera is then used to create a picture of areas of radioactivity in the body. Some children might need medicine to help them relax or even go to sleep during the test.
The PET scan image is not as detailed as a CT or MRI scan, but it can provide helpful information about whether abnormal areas seen on other tests (such as MRIs) are likely to be tumors or not. This test is more likely to be helpful for fast-growing (high-grade tumors) than for slower-growing tumors.
This test is also useful after treatment to help determine if an area that still looks abnormal on an MRI scan is remaining tumor or if it is more likely to be scar tissue. Remaining tumor might show up on the PET scan, while scar tissue will not.
Type of Tumor – 5-Year Survival Rate:
Pilocytic astrocytoma – About 95%
Diffuse astrocytoma – About 80% to 85%
Anaplastic astrocytoma – About 25%
Glioblastoma – About 20%
Oligodendroglioma – About 90%
Ependymoma/anaplastic ependymoma – About 75%
Embryonal tumors (includes medulloblastoma) – About 60% to 65%
Brain and spinal cord tumors are the second most common cancers in children (after leukemia). They account for about 1 out of 4 childhood cancers. More than 4,000 brain and spinal cord tumors are diagnosed each year in children and teens. The incidence rate (number of tumors per 100,000 children) has not changed much in recent years.
Malignant (fast-growing) brain and spinal cord tumors are slightly more common in boys, while non-malignant tumors are slightly more common in girls.
About 3 out of 4 children with brain tumors (all types combined) survive at least 5 years after being diagnosed. But the outlook can vary a great deal based on the type of tumor, where it is, and other factors.
COMMUNICATING WITH YOUR CHILD
Here are a few quick tips to help you focus on how to approach and enhance communication with your child.
Practice communication strategies before your child needs to use them.
Practice more than one signal for “yes;” no response can be used to mean “no.”
Start by asking broad questions, and then ask more and more specific questions as you get an idea of what your child is thinking about or wanting to say.
Use simple sentences to get to the main point.
For example, ask “Are you hungry?” instead of “Do you want something for dinner?” Remember the “KIS” principle: “Keep It Simple.”
Remind your child what the “yes” signal is before asking each question.
Wait longer than usual for your child to respond.
If your child has difficulty responding, repeat the question or simplify it. For example, if you’ve asked, “Are you hungry?” simplify by saying, “Hungry?”
To ensure your child’s message is understood correctly, repeat what you think he said. For example, “Okay, you are hungry,” or “So you’re not hungry.” This allows your child to confirm that his message was interpreted correctly.
Be patient with yourself, your child, and the process.
When exploring emotional issues, ensure that you understand your child’s unique perspective rather than thinking about it only from an adult perspective. In other words, focus on how your child thinks and feels, not how you would think or feel in the same situation.