Whole Brain Radiation Therapy (WBRT) is a form of radiation treatment directed at the entire brain. This approach involves using high-energy rays to target and destroy cancer cells that may be present throughout the brain. The primary goal of WBRT is to address cancer spread within the brain.
Purpose and Indications
Whole Brain Radiation Therapy is primarily used to manage cancer that has spread to the brain from other parts of the body, known as brain metastases. It is often considered when multiple tumors are present or when undetectable cancer cells are suspected throughout the brain. WBRT can help alleviate neurological symptoms caused by these tumors, such as headaches, nausea, seizures, or motor function difficulties, by shrinking the existing lesions.
Another application of WBRT is Prophylactic Cranial Irradiation (PCI). This is used in certain high-risk cancers, such as small cell lung cancer, to prevent cancer cells from spreading to the brain. In these cases, WBRT aims to eliminate any undetectable cancer cells before they can form visible tumors. This helps control the disease within the brain, potentially improving a patient’s overall well-being and extending life.
How Whole Brain Radiation is Administered
Undergoing Whole Brain Radiation Therapy involves a precise planning and delivery process. The first step is a simulation, where a patient undergoes a CT scan of the head. During this scan, a custom-made immobilization device, such as a plastic mesh mask, is created to ensure the head remains perfectly still and in the same position for every treatment session.
Treatment sessions are delivered using a linear accelerator, a machine that produces the radiation beams. Patients lie still on a treatment table, often wearing their custom mask, while the machine moves around them to deliver radiation from specific angles. The radiation delivery is painless.
WBRT is typically delivered in daily fractions, usually Monday through Friday, over a period ranging from one to three weeks. A common schedule involves 5 to 15 treatments over one to three weeks, depending on the specific treatment plan. Each session usually lasts about 15 to 30 minutes, with most time spent on precise positioning, while actual radiation delivery is much quicker. A team of specialists, including radiation oncologists, plans and delivers the treatment accurately.
Potential Side Effects and Management
Patients undergoing Whole Brain Radiation Therapy may experience a range of side effects, which can vary in severity and duration. One common short-term effect is fatigue, often lasting for several months. Hair loss on the scalp is another frequent acute side effect; hair usually begins to regrow three to six months after therapy, sometimes with a different texture.
Other acute effects can include skin irritation and redness in the treated area, similar to a sunburn, as well as nausea, vomiting, and headaches. Some patients might experience a temporary worsening of neurological symptoms or increased pressure in the brain due to swelling, which can be managed with medications like steroids. In some instances, somnolence syndrome (severe tiredness and drowsiness) can occur after treatment completion.
Long-term side effects can emerge months or even years after WBRT. Cognitive changes, such as difficulties with memory, processing speed, attention, or problem-solving, are a recognized concern. In rare cases, radiation necrosis, the formation of dead brain tissue, can develop. Management strategies include supportive care, anti-nausea medications, and specific guidance for scalp care, such as gentle washing and sun protection.
Considerations and Outlook
Decisions regarding Whole Brain Radiation Therapy are made in close consultation with the medical team, weighing the potential benefits against the risks. After completing WBRT, ongoing monitoring and follow-up care are typically recommended. This often includes regular MRI scans of the brain to track progress and detect any changes. These appointments allow the medical team to assess the treatment’s effectiveness and manage any long-term side effects that may arise.
The overall objective of WBRT extends beyond tumor control to improving a patient’s quality of life. While WBRT can relieve symptoms and extend survival for many, the potential for cognitive effects is a consideration in treatment planning.