Having a tumor in the brain is always a very serious matter, and a low-grade glioma is no exception. Low-grade gliomas are a class of slow-growing, less aggressive tumors that can occur in a number of places in the brain and spinal cord. In general, low-grade gliomas have a more positive prognosis than malignant, high-grade types of brain cancer.
- There are more 1,000 cases of pediatric low-grade gliomas each year in the United States.
- Low-grade gliomas are the most common types of pediatric brain tumors.
- They most commonly arise from a specific type of cell known as a glial cell, or astrocyte.
- Astrocytes make up the supportive network of the brain, and get their name from their star-like shape.
- Astrocytomas (tumors that begin in astrocytes) are the most common central nervous system (brain and spinal cord) tumor found in children.
As you read on, you’ll find detailed information about low-grade gliomas.
How Dana-Farber/Boston Children's Cancer and Blood Disorders Center approaches low-grade gliomas
Patients with low-grade gliomas are treated at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center through our Glioma Program, the world’s largest pediatric glioma treatment program.
Dana-Farber/Boston Children's is also home to the world’s largest pediatric low-grade glioma research program, the Pediatric Low-Grade Astrocytoma (PLGA) Program. Through the PLGA Program, we conduct advanced research on the genetic and molecular causes of low-grade glioma.
After treatment, your child will receive expert follow-up brain tumor survivorship care through the Stop & Shop Family Pediatric Neuro-Oncology Outcomes Clinic, where he will be able to meet with his neurosurgeon, radiation oncologist, pediatric neuro-oncologist and neurologists at the same follow-up visit.
- Our pediatric brain tumor survivorship clinic is held weekly.
- In addition to meeting with your pediatric neuro-oncologists, neurologist and neurosurgeon, your child may also see one of our endocrinologists or alternative/complementary therapy specialists.
- School liaisons and psychosocial personnel from the pediatric brain tumor team are also available.
- If your child needs rehabilitation, he may also meet with speech, physical and occupational therapists during and after treatments.
We understand how overwhelming a diagnosis of a 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 here, 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 most commonly arise from a specific type of cell known as a glial cell, or astrocyte.
How are low-grade 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.
There are four major types of astrocytomas, classified based on what they look like under a microscope.
- grade I (pilocytic astrocytoma - benign)
- grade II (fibrillary astrocytoma)
- grade III (anaplastic astrocytoma – refers to lack of structure in the cell)
- grade IV (glioblastoma multiforme – the most serious kind of tumor)
Low-grade gliomas are usually either grade I or grade II.
Low-grade gliomas may also be classified according to their location in the brain. This includes:
- 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)
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)
The other two types of astrocytomas are classified as high-grade gliomas:
- grade III or anaplastic astrocytoma
- grade IV or glioblastoma multiforme
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:
- tuberous sclerosis
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.
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?
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/Boston Children's are cared for at the Jimmy Fund Clinic on the third floor of Dana Farber Cancer Institute. If your child needs to be admitted to the hospital, he will stay at Boston Children’s Hospital 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.
Q: What kind of supportive or palliative care is available for my child?
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.
The first step in treating your child is forming an accurate and complete diagnosis, so your child’s physician may order a number of different tests to determine the type and location of the tumor. Diagnostic procedures for a brain tumor are used to determine the exact type of tumor and whether the tumor has spread. In addition to a physical exam, a medical history and neurological exam (a test of reflexes, muscle strength, eye and mouth movement, coordination and alertness), your child may require tests such as:
- computerized tomography scan (also called a CT or CAT scan) - a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images of the body. CT scans are more detailed than general x-rays. If a low-grade glioma is suspected, your child may have a CT scan of the brain.
- magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of the brain and spine. For low-grade gliomas, an MRI of the brain is usually done. In the rare event that your child’s low-grade gliomas spread to the spine, an MRI of the spine may also be ordered.
- biopsy - in many cases, a tissue sample from the tumor will be taken through a needle during a simple surgical procedure to confirm the diagnosis. However, with low-grade gliomas of the optic pathway and brain stem, surgery (including biopsy) is generally avoided, due to the very delicate structures in these areas.
After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. Then we will meet with you and your family to discuss the results and outline the best treatment options.
Treatment & care
We know how difficult a diagnosis of a pediatric brain tumor can be, both for your child and for your whole family. That’s why our physicians are focused on family-centered care: From your first visit, you’ll work with a team of professionals who are committed to supporting all of your family’s physical and psychosocial needs. We’ll work with you to create a care plan that’s best for your child.
If your child has been diagnosed with a low-grade glioma, you’ll naturally be eager to know how your child’s physician will treat the tumor. Your child’s physician will determine a specific course of treatment based on several factors, including:
- your child's age, overall health and medical history
- type, location, and size of the tumor
- extent of the disease
- your child's tolerance for specific medications, procedures or therapies
- how your child's doctors expects the disease to progress
There are a number of treatments we may recommend. Some of them help to treat the tumor while others are intended to address complications of the disease or side effects of the treatment.
What treatments are available for low-grade gliomas?
If your child has been diagnosed with a low-grade glioma, he may receive one or more of the following treatments:
- neurosurgery - usually the first step in the treatment of brain tumors. The goal is to remove as much of the tumor as possible without compromising neurological function.
- radiation therapy - using high-energy rays (radiation) from a specialized machine to damage or kill cancer cells and shrink tumors. Due to the long-term damage that radiation can cause to the developing brain of a child, this treatment is usually only used as a last resort.
- chemotherapy - a drug treatment that works by interfering with the cancer cell's ability to grow or reproduce. Modern treatments now include biologic (also called smart drugs) that target specific abnormal pathways required by the tumor to grow and spread. A number of these types of drugs are now in clinical trials in children with low-grade gliomas.
What is expected post-treatment for low-grade glioma?
The prognosis for a child with a low-grade glioma depends on tumor grade, location and in some cases, age of the child at diagnosis.
- Many low-grade gliomas are first treated with surgery and then monitored for regrowth. Grade I astrocytomas, for example, are usually cured with complete surgical removal alone.
- If, due to the tumor’s location, complete surgical resection is not an option (optic pathway or brain stem gliomas, thalamic/hypothalamic or cervico-medullary gliomas) or if a tumor begins to grow back after it has been removed, the doctor may recommend chemotherapy.
- We usually don’t use radiation therapy unless your child’s tumor has grown after chemotherapy. Due to the potential side effects of radiation, including effects on learning and hormone function, it is best avoided if your child is young (especially under age 10).
What is chemotherapy?
Chemotherapy is systemic treatment, meaning it is introduced to the bloodstream and travels throughout the body to kill cancer cells. Different groups of chemotherapy drugs work in different ways to fight cancer cells and shrink tumors.
How is chemotherapy given?
Your child may receive chemotherapy:
- orally, as a pill to swallow
- intramuscularly, as an injection into the muscle or fat tissue
- intravenously, directly to the bloodstream (intravenously or IV)
- intrathecally, directly into the spinal fluid with a needle (intrathecally)
Does chemotherapy cause side effects?
While chemotherapy can be quite effective in treating certain cancers, the agents do not differentiate normal healthy cells from cancer cells. Because of this, your child may experience adverse side effects during treatment. Being able to anticipate these side effects can help you, your child and your care team prepare for, and, in some cases, prevent these symptoms from occurring, if possible.
How are side effects managed?
Side effects in the treatment of low-grade gliomas can arise from surgery, radiation and chemotherapy.
- Procedures should be performed in specialized centers where experienced neurosurgeons, working in the most technologically advanced settings, can provide the most extensive resections while preserving normal brain tissue.
- Radiation therapy often produces inflammation, which can temporarily exacerbate symptoms and dysfunction. To control this, inflammation steroids are sometimes necessary.
- Some of the chemotherapy agents are associated with fatigue, diarrhea, constipation and headache. These side effects can be effectively managed under most circumstances with standard medical approaches.
Our Pediatric Brain Tumor Program also has access to specialists who deliver complementary or alternative medicines. These treatments, which may help control pain and side effects of therapy include the following.
- therapeutic touch
- dietary recommendations
Talk to your child’s physician about whether complementary or alternative medicine might be a viable option.
What about progressive or recurrent disease?
There are numerous standard and experimental treatment options for children with progressive or recurrent low-grade gliomas.
Dana-Farber Cancer Institute is one of nine institutes in the nation belonging to the Pediatric Oncology Experimental Therapeutic Investigators Consortium. The consortium is dedicated to the development of new and innovative treatments for children with newly diagnosed as well as progressive or recurrent brain tumors. We are also home to the world’s largest pediatric low-grade astrocytoma research program and the Department of Defense Neurofibromatosis Clinical Trial Consortium.
Today, the majority of children and adolescents diagnosed with pediatric brain tumors will survive into adulthood. However, many of them will face physical, psychological, social and intellectual challenges related to their treatment and will require ongoing assessment and specialized care.
To address the needs of this growing community of brain tumor survivors, Dana-Farber/Boston Children's established the Stop & Shop Family Pediatric Neuro-Oncology Outcomes Clinic.
Today, more than 1,000 pediatric brain tumor survivors of all ages are followed by the Outcomes Clinic, a multi-disciplinary program designed to address long-term health and social issues for families and survivors of childhood brain tumors. Some of the post-treatment services provided by the Outcomes Clinic include:
- MRI scans to monitor for tumor recurrences
- intellectual function evaluation
- endocrine evaluation and treatment
- neurologic assessment
- psychosocial care
- hearing, vision monitoring
- ovarian dysfunction evaluation and treatment
- motor function evaluation and physical therapy
- complementary medicine
As a result of treatment, children may experience changes in intellectual and motor function. Among several programs addressing these needs are the School Liaison and Back to School Programs, which provide individualized services to ease children's return to school and maximize their ability to learn. In addition to providing thorough and compassionate care, our Outcomes Clinic specialists conduct innovative survivorship research and provide continuing education for staff, patients and families
Research and Innovations
Dana-Farber/Boston Children's is a member of the Pediatric Oncology Therapeutic Experimental Investigators Consortium (POETIC), a collaborative clinical research group offering experimental therapies to patients with relapsed or refractory disease. It is also the New England Phase I Center of the Children's Oncology Group and a member of the Department of Defense Neurofibromatosis Clinical Trial Consortium.
We are home to the only dedicated pediatric low-grade glioma program, the Pediatric Low-Grade Astrocytoma (PLGA) Program. In addition to the discovery of a number of novel targets, this program has initiated a number of phase II protocols using molecular inhibitors for children with progressive/recurrent low-grade glioma.
Through the PLGA Research Program, we have pioneered strategies for analyzing the genetic and molecular characteristics of pediatric low-grade astrocytomas. In collaboration with the Broad Institute of Harvard and MIT, we have made strides towards a better understanding of these conditions. Through the program, we’ve also established a patient registry and multiple international research projects.
For many children with rare or hard-to-treat conditions, clinical trials provide new options.