Pediatric low-grade gliomas (pLGG) are the most common brain tumors in children and young adults. The outlook for these tumors is excellent because they're usually not cancer, and they often grow very slowly. But if the tumors do grow, they can cause damage. That's why it's important for you or your child to get on the right treatment to slow pLGG.
If the tumor does grow, the primary treatment is surgery with the goal of removing as much of the tumor as possible. Completely removing the tumor often cures the cancer. But the tumor must be in a part of the brain or spinal cord where a surgeon can remove it.
Your doctors will create a treatment plan based on the size and location of the tumor and how fast it grows.
Surgery for pLGG
A very small tumor that doesn't cause symptoms may not need treatment right away. The doctor may just watch it with imaging scans. For a bigger tumor that does cause symptoms, it's important to get treatment as soon as possible.
The surgeon will try to remove as much of the tumor as possible. Taking out the whole tumor can cure many children and teens with pLGG.
Surgery can sometimes cause problems like these:
- Infection
- Bleeding
- Weak muscles
- Trouble speaking
- Vision loss
Your doctor will try to prevent these side effects or manage them if they happen.
It's not always possible to remove a tumor, especially if it's near sensitive areas like the optic nerve that helps you see. Even if the surgeon has to leave a small piece of the tumor in place, having surgery may stop it from growing. Some kids may need another surgery if their tumor does grow back.
If some of the tumor is left after surgery, the doctor will do regular magnetic resonance imaging (MRI) scans to check it for signs of growth.
Chemotherapy for pLGG
Chemotherapy uses strong medicines to kill or shrink tumor cells. Doctors use this treatment for young children whose tumors grow and cause symptoms. Chemotherapy is also an option when the tumor is in a part of the brain where it's not safe to do surgery.
A few chemotherapy drugs treat pLGG, including:
- Carboplatin (Paraplatin)
- Vinblastine (Velban)
- Vincristine (Oncovin)
Combining two or more of these medicines may help them work better.
For pLGG in which the tumors are growing or can't be removed with surgery, doctors may use:
- Vinblastine
- A combination of carboplatin and vinblastine
- TPCV: a combination of thioguanine (Tabloid), procarbazine (Matulane), CCNU –also known as lomustine (Gleostine) – and vincristine
Doctors give chemo drugs by mouth or into the bloodstream. Because these medicines are very strong, doctors will often give children a low dose over many months.
Chemotherapy can shrink tumors. Some patients won't need further therapy afterward. But for others, even if chemotherapy doesn't make the tumors go away, it can slow or stop them from growing and relieve symptoms. Because this treatment kills healthy cells along with tumor cells, it can cause side effects like these:
- Hair loss
- Tiredness and shortness of breath from low red blood cells
- Bigger risk of infection from a drop in white blood cells
- Bleeding and bruising from low platelets
- Constipation or diarrhea
- Balance problems
- Problems having a baby in the future
For a long time chemotherapy was reserved for cases that continued after radiotherapy. But changing recommendations now push for its early use, especially in younger age groups. The carboplatin and vincristine (CV) combination stands as a standard systemic therapy for pLGG, with differences in dosage and how it's given between North America and Europe.
Radiation for pLGG
This treatment uses high-energy rays to kill tumor cells or stop them from growing. A machine sends radiation to the brain or spinal cord.
Doctors try to limit the use of radiation in children with pLGG because it can cause serious side effects like:
- Thinking and memory problems
- Hormone changes
- Slow growth
- Damage to blood vessels
- New cancers
This treatment is usually just for older kids whose tumors didn't shrink enough or came back after surgery, chemotherapy, or targeted medicine.
New types of radiation are more focused. They aim a thinner beam of energy right at the tumor. This helps avoid damage to healthy parts of the brain.
Targeted Treatments for pLGG
Some tumor cells have changes in their genes that help them grow and divide. Targeting the things that help the tumor grow is a more recent way to treat pLGG.
Newer medicines called targeted drugs treat gliomas with certain gene changes. These medicines block different mutated or fused proteins that help the pLGG grow. Targeted drugs for pLGG include:
- Dabrafenib (Tafinlar)
- Tovorafenib (Ojemda)
- Trametinib (Mekinist)
You take these medicines by mouth as pills or liquid.
A combination targeted therapy, Tafinlar and Mekinist, is approved for children whose tumor has the gene mutation BRAF V600E and has returned. The combination is also approved for use in those with newly diagnosed pLGG. In 2024, the FDA approved Ojemda for children 6 months or older living with pediatric low-grade glioma (pLGG) that returned or did not respond to treatment and who have certain changes in the BRAF gene.
Ask your care team to help you understand which treatment option is best for your child.
Side effects of targeted treatments are different from those of chemotherapy and include:
- Itchy skin
- Rash
- Headache
- Sensitivity to the sun
- Fever or chills
- Joint or muscle pain
- Tiredness
- Cough
A small number of people who have taken these medicines got skin cancer. Your child's doctor will check their skin often during treatment. Let the doctor know if you see any new growths or skin changes.
Supportive Care
Any of the treatments for pLGG can cause side effects. Your treatment team has medicines to manage problems like fever, pain, nausea, and vomiting. They can also answer your questions and help you deal with the emotions of having a child with a tumor.
Clinical Trials for pLGG
Every new targeted therapy for pLGGs started out in a clinical trial. These studies test new medicines to see how well they work. The goal is to improve survival and reduce treatment side effects. By enrolling in a clinical trial, you or your child could get access to a new and possibly better treatment than what's available now.
The researchers who run these studies do everything possible to make sure that everyone who joins them is safe. Before you or your child sign up for a study, talk to your doctor and to the doctor who runs the trial. Ask how the new drug might help and which side effects it could cause. Remember that you can leave the trial at any time for any reason.
The Outlook After Treatment
Scientists have learned a lot about pLGGs and how they grow. What they've learned has led to new treatments that have improved the outlook for children and teens with these tumors. Most pLGGs grow slowly and respond well to treatment.
But because these tumors can start to grow again after treatment, you or your child will get regular MRI scans to check for new tumor growth. The doctor will also monitor for side effects of treatment, such as slow growth and learning problems.
Show Sources
Photo Credit: Johner Images/Getty Images
SOURCES:
American Brain Tumor Association: "Pediatric Low-Grade Gliomas (LGG)," “Treatments and Side Effects.”
American Cancer Society: "Targeted Therapy Drugs for Brain and Spinal Cord Tumors in Children."
Brain Tumor Research and Treatment: "Medical Treatment of Pediatric Low-Grade Glioma."
Cancers (Basel): "Pediatric Low-Grade Gliomas."
Child's Nervous System: "Chemotherapy in pediatric low-grade gliomas (PLGG)."
Current Opinion in Pediatrics: "Management of Pediatric Low-Grade Glioma."
Dana-Farber Cancer Institute: "Childhood Low-Grade Gliomas."
FDA: "Should Your Child Participate in a Clinical Trial?" "FDA D.I.S.C.O. Burst Edition: FDA approval of Ojemda (tovorafenib) for relapsed or refractory pediatric low-grade glioma harboring a BRAF fusion or rearrangement, or BRAF V600 mutation."
MedlinePlus: "Lomustine."
Nationwide Children's: "Low-grade Glioma."
Neoplasia: "Pediatric low-grade glioma: Targeted therapeutics and clinical trials in the molecular era."
Pediatric Brain Tumor Foundation: "FDA Approves First Combination Targeted Therapy for Most Common Pediatric Brain Cancer."
St. Jude Children's Research Hospital: "Low-grade glioma," "Low-Grade Glioma Treatment."
