Pediatric glioblastoma is an uncommon and aggressive brain tumor affecting children. Classified as a high-grade glioma (Grade IV), it is characterized by rapid growth and invasive nature within the central nervous system. While sharing a name with its adult counterpart, pediatric glioblastoma exhibits distinct molecular and genetic characteristics. This means adult research findings and treatment strategies cannot be directly applied to children, as their tumors often arise in different brain regions and have unique genetic alterations.
Symptoms of Pediatric Glioblastoma
Symptoms of glioblastoma in children vary depending on the tumor’s size and location. They often arise from increased intracranial pressure, leading to persistent headaches (often worse in the morning), nausea, and vomiting. Children may also exhibit increased lethargy or changes in activity levels due to this pressure.
Other symptoms are directly related to the tumor’s location. These include new-onset seizures, problems with balance or coordination (such as difficulty walking steadily), and vision changes (including blurred or double vision). Weakness in one or more limbs, or subtle shifts in personality and behavior (such as increased irritability or withdrawal), are also possible indicators. Since many of these symptoms can resemble more common childhood illnesses, it is important to consult a doctor if they are persistent or severe.
The Diagnostic Process
Confirming a diagnosis of glioblastoma in children involves clinical procedures designed to identify the tumor and understand its characteristics. The process begins with a thorough neurological examination, where a doctor assesses the child’s reflexes, coordination, vision, and mental status to identify any abnormalities. Following this initial assessment, neuroimaging techniques visualize the brain. Magnetic Resonance Imaging (MRI) scans provide detailed images of brain structures, showing the tumor’s size, location, and extent. Computed Tomography (CT) scans may also be used, offering cross-sectional images that quickly identify large tumors or swelling.
A definitive diagnosis relies on a biopsy, involving surgically removing a small sample of tumor tissue. This tissue is sent to a pathology lab for microscopic analysis. Pathologists examine the cells to determine the tumor type and grade, confirming it is glioblastoma. The analysis also includes molecular and genetic testing, identifying specific mutations and genetic markers within the tumor cells. This detailed molecular profile helps understand the tumor’s biology and guide treatment selection.
Standard Treatment Approaches
Treating pediatric glioblastoma involves a multi-faceted approach, combining several modalities. Surgical resection is usually the initial step, aiming to safely remove as much tumor as possible without causing further neurological damage. The extent of tumor removal, known as gross total resection, often correlates with better outcomes, though complete removal can be challenging due to the tumor’s infiltrative nature.
Following surgery, radiation therapy targets and eliminates any remaining cancer cells. This treatment uses high-energy beams to damage cancer cell DNA, preventing growth and division. For children, specialized techniques like proton beam therapy are often preferred. Protons deliver a more precise radiation dose to the tumor, minimizing exposure to surrounding healthy, developing brain tissue. This precision helps reduce potential long-term side effects on cognitive function and growth.
Chemotherapy uses medications to kill cancer cells throughout the body, either by stopping their growth or destroying them directly. These drugs can be administered orally or intravenously. Specific agents and protocols for children may differ from adults due to varying tumor biology and tolerance. Common chemotherapy drugs include temozolomide, which damages cancer cell DNA, or other agents in combination regimens. Chemotherapy aims to reduce tumor size, destroy microscopic disease, and improve overall disease control.
Prognosis and Current Research
The prognosis for pediatric glioblastoma presents significant challenges due to the tumor’s aggressive nature. Outcomes are influenced by factors like the extent of surgical removal and the tumor’s specific molecular and genetic characteristics. Each child’s response to treatment varies, so providing definitive statistics for individual cases can be misleading. Despite these difficulties, ongoing research continuously explores new treatment avenues.
Current research focuses on developing targeted therapies: drugs designed to attack specific genetic mutations or pathways within tumor cells. Studies investigate inhibitors targeting the PDGFRA gene (frequently amplified in pediatric glioblastomas) or therapies addressing histone H3 mutations like K27M. These therapies aim to be more precise and less toxic than traditional chemotherapy, potentially improving outcomes and reducing side effects.
Immunotherapy is another promising area, focusing on harnessing the body’s immune system to fight cancer. Researchers explore ways to activate a child’s immune cells to recognize and destroy glioblastoma cells, potentially through treatments like CAR T-cell therapy or checkpoint inhibitors. These novel approaches often occur within clinical trials, which test new treatments in a controlled environment. Participation in clinical trials is important for advancing glioblastoma understanding and developing more effective, less toxic therapies for children.