What Are High Grade Gliomas?
High-grade gliomas are tumors of the glial cells. Glial cells are found in the brain and spinal cord. The tumors are called “high-grade” because they are fast-growing and spread quickly. This makes them hard to treat. The tumors occur in people of all ages, from infants to adults.
High-grade gliomas are rare and account for 8-12% of all childhood brain tumors. They occur equally in males and females.
High-grade gliomas are classified by their location and by how they appear when examined under a microscope. Classifying the tumor helps determine how the disease will progress and helps identify the best treatment for it. Although the outlook for high-grade gliomas is generally poor, some people can be cured.
Causes
Sometimes, high doses of radiation therapy can cause high-grade gliomas. The reason for most high-grade gliomas in children is not known. Although doctors continue their research to understand what causes the tumors to occur, there have been few reliable findings. Genetic causes are rare, and these tumors are not believed to be linked to anything in the environment. Genetics specialists can discuss with families if genetic testing is needed.
Signs and Symptoms
The symptoms of a brain tumor often depend on where it is located. One of the most common signs of high-grade gliomas is headaches, particularly headaches that wake children up in the morning and are associated with vomiting. High-grade gliomas can also cause seizures or cause young children to miss developmental milestones. Sometimes, tumors can cause problems with vision, hearing, speech or balance. These symptoms can also be related to other health conditions. If your child displays any of these, it is important to have a thorough medical exam.
Diagnosis
The first step in diagnosing a brain tumor is usually to take an image of the brain and / or spine using a CT scan or MRI . These tests can help show if a tumor is present. To definitively diagnose a high-grade glioma, a biopsy is required. In a biopsy, doctors examine a small sample of the tumor tissue. This helps determine the specific type of tumor and can help detect the presence of certain biological “markers” in the tumor. These markers may be used to help determine treatment.
Treatment
The primary treatment for high-grade gliomas is to perform surgery to remove the tumor. Surgery is performed only when it can be done safely, without causing additional damage to the brain. Some types of tumors, such as diffuse midline gliomas, cannot be removed due to their location in delicate and crucial areas of the brain.
In addition to surgery, most children will also receive radiation therapy and / or chemotherapy, depending on their age and type of tumor. When tumors continue to grow even after chemotherapy and radiation, clinical trials may be considered.
Outlook
Current treatments for high-grade gliomas will cure some children, but many tumors continue to grow despite our best therapies.
Research is underway to better understand these tumors to develop more effective therapies. At Cincinnati Children’s, our researchers have also been able to develop laboratory models of high-grade glioma tumors to study their biology. They use these models to design and test different ways to treat these tumors. The goal is to move new treatments as rapidly and safely as possible from the laboratory into clinical studies that will help patients.
