Low-grade gliomas

We understand how overwhelming a diagnosis of a low-grade glioma can be. Right now, you probably have a lot of questions. How dangerous is this condition? What is the very best treatment? What do we do next?

We’ve tried to provide some answers to those questions in the following pages, and our experts can explain your child’s condition fully when you meet with us.

What is a low-grade glioma?

Low-grade gliomas are a class of slow-growing, less aggressive tumors of the central nervous system. They arise from a specific type of cell known as a glial cell. Most low-grade gliomas come from a specific kind of glial cell, called an astrocyte. These gliomas are also called astrocytomas.

How are gliomas classified?

An important part of diagnosing a brain tumor involves staging and classifying the disease, which will help your child’s doctor determine treatment options and prognosis. Staging is the process of determining whether the tumor has spread and, if so, how far.

1. There are four major types of gliomas, classified based on what they look like under a microscope.

low grade:

• grade I (pilocytic astrocytoma)
• grade II (fibrillary astrocytoma)

high grade:

• grade III (anaplastic astrocytoma)
• grade IV (glioblastoma multiforme)

2. Low-grade gliomas may also be classified according to their location in the brain. These include:

• cerebellar pilocytic astrocytoma (the part of the brain known as the cerebellum)
• cervico-medullary astrocytoma (the brainstem)
• optic pathway glioma (the optic nerve)
• tectal glioma (the “roof” of the brainstem)
• thalamic/hypothalamic astrocytoma (the parts of the brain known as the thalamus or hypothalamus)

Are all gliomas astrocytomas?

No, but most are. Other types of low-grade gliomas include:

• oligodendroglioma (very rare—account for only 2 percent of all pediatric brain tumors)
• ganglioglioma (tumors have properties of both glial cells and neuronal cells) 
• pleomorphic xanthoastrocytoma (associated with a higher seizure rate than other low-grade gliomas)

Causes

What causes low-grade gliomas?

As a parent, you undoubtedly want to know what may have caused your child’s tumor. It’s important to understand that low-grade gliomas most often occur with no known cause. There’s nothing that you could have done or avoided doing that would have prevented the tumor from developing.

Research has shown that there is a link between some types of low-grade gliomas and certain genetic diseases, specifically:

• neurofibromatosis
• tuberous sclerosis

Symptoms

What are the symptoms of low-grade gliomas?

The symptoms of low-grade gliomas can vary greatly depending on the size and location of the tumor and whether it has infiltrated into other areas of the brain or spine.

Due to the relative slow growth rate of low-grade gliomas, your child’s symptoms may have begun many months or years before they see the doctor. While each child may experience symptoms differently, some of the most common include:

• change in / loss of vision due to low-grade gliomas of the visual pathway
   
• weight gain or loss and/or premature puberty due to low-grade gliomas in the hormone center of the brain
   
• problems with movement or bowel/bladder control due to low-grade gliomas in the spine
   
• vomiting, headache, fatigue and motor control problems due to fluid build-up in and increased pressure on the brain
   
• seizures due to irritation of the normal brain cells

Keep in mind that these symptoms may resemble other, more common conditions or medical problems. If you don’t have a diagnosis and are concerned, always consult your child's physician.

Glossary

Questions to ask your child’s doctor

After your child is diagnosed with a brain tumor, you may feel overwhelmed with information. It can be easy to lose track of the questions that occur to you.

Lots of parents find it helpful to jot down questions as they arise – that way, when you talk to your child’s doctors, you can be sure that all of your concerns are addressed. 

If your child is old enough, you may want to suggest that she write down what she wants to ask her health care provider, too.

Some of the questions you may want to ask include:

• What type of brain tumor does my child have?
• Where in the brain is the tumor located? How might this affect my child?
• Has my child’s brain tumor spread?
• Can the tumor be treated with surgery?
• How long will my child need to be in the hospital?
• What are the possible short and long-term complications of treatment? How will they be addressed?
• What is the likelihood of cure?
• What services are available to help my child and my family cope?

FAQ

Q: What causes low-grade gliomas?

A: As a parent, you undoubtedly want to know what may have caused your child’s tumor. The vast majority of children with low-grade gliomas develop these tumors spontaneously, meaning that there is no identifiable cause. A small percentage can be associated with certain genetic syndromes.  Your doctor can easily determine if a genetic cause is associated with the development of your child’s tumor.

Q: Will my child be OK after treatment for low-grade glioma?

A: The outcome after treatment for low-grade glioma can vary significantly depending on the location of the tumor, whether or not the tumor has spread and whether the tumor can be completely removed through surgery. In general, low-grade gliomas have a more positive prognosis than malignant, high-grade types of brain cancer. Your doctor will discuss treatment options with you and your family including clinical trials and supportive care.

Q: Where will my child be treated?

A: Children treated on an outpatient basis through Dana-Farber/Children’s Hospital Cancer Center are cared for at the Jimmy Fund Clinic on the third floor of the Dana Farber Cancer Institute. If your child needs to be admitted to the hospital, he will stay at Children’s Hospital Boston on the ninth floor of the Berthiaume Building.

Q: What services are available to help my child and my family cope?

A: We offer a variety of services to help you, your child and your family get through this difficult time. Click here to read more about our support services.

Q: What kind of supportive or palliative care is available for my child?

A:When necessary, our Pediatric Advanced Care Team (PACT) offers supportive treatments intended to optimize the quality of life and promote healing and comfort for children with life-threatening illness. In addition, PACT can provide psychosocial support and help arrange end-of-life care when necessary.