Brain cancer is the leading cause of solid tumor cancer death in children and adolescents under age 20, the second leading cause of cancer-related death for men aged 20 to 39, and the fifth leading cause for women aged 20 to 39 years. Brain cancer does not discriminate, and no truly preventive measures exist.
In 2015, approximately 23,180 American adults will be diagnosed with brain cancer, and approximately 14,000 deaths will occur from primary malignant brain tumors.
There are 120 types of brain tumors that rarely spread outside of the brain and spinal cord. Gliomas (all tumors found in the supportive brain tissue) represent 80% of all malignant brain tumors.
There are no known causes for brain tumors. Many risk factors have been studied, but only exposure to radiation (high-dose x-rays) was found to consistently increase the risk for a brain tumor. However, in recent decades, radiation has become more focused on the affected area. In addition, doctors, dentists, and technicians are now taking more precautions when using radiation so the risk for brain tumors from radiation is currently low.
Research attempting to link cell phone use and brain tumors is also common, but multiple studies have shown inconsistent results. Studies comparing risks identified with short-term and long-term cell phone use (10 years or more) have also produced conflicting results.
According to the National Cancer Institute and the American Brain Tumor Association, further research is needed to fully understand the impact of cell phone use on brain tumors.
Genetically, only 5% of benign and malignant brain tumors may be connected to hereditary risk factors. There are only a few, very rare, inherited genetic syndromes that involve brain tumors.
The majority of genetic risk factors for brain tumors are accumulated over time, not inherited at birth. With increasing age, certain genes may begin to function abnormally, abandoning their normal roles in suppressing tumors, monitoring cell growth, and controlling immune response.
A brain tumor is often found when it interferes with normal body functions, making its presence impossible to ignore. The most common symptoms of a brain tumor include:
- Changes in speech, vision, or hearing
- Problems with balance
- Memory issues
- Numbness in the arms and legs
After discussing your family and health history, the doctor will perform a basic neurologic exam that checks your vision, alertness, reflexes, hearing, and coordination. An eye exam is also often used to check for swelling.
If the results of the neurologic exam lead the doctor to suspect a brain tumor, a CT scan and/or an MRI will be ordered. These imaging methods use special dye that is injected before the images are taken to make abnormal areas easy to see. In some cases, a spinal tap or a biopsy may also be performed.
Researchers are currently studying biomarkers that are indicators of cancer and are found in the blood, urine, and tissue.
The 5-year survival rate after a diagnosis of a malignant brain tumor is approximately 34%.
Treatment for malignant brain tumors depends on the tumor’s type and grade, location, and size, as well as the patient’s age and general health.
Treatment options typically include surgery, radiation therapy, and chemotherapy. Most brain tumors are treated with a combination of these options.
When possible, surgery is the first treatment. The goals of surgery are to make an accurate diagnosis, and to remove as much of the tumor as possible to relieve pressure on the brain and nerves, while maintaining brain function.
Surgery is often followed by radiation therapy, which will destroy any remaining cancer cells. Several types of radiation are used for brain tumors, including 3-D scans to target the radiation more directly on the tumor.
For inoperable tumors that are unlikely to be cured, joining a clinical trial may be a good option. There are more than 12,000 clinical trials in a searchable database, www.cancer.gov/clinicaltrials/search.
Brain cancer appeared in headlines in March, when “60 Minutes” spotlighted a clinical trial using a reengineered polio virus to kill cancer cells in glioblastoma, the most common and aggressive malignant brain tumor. The trial is still in its first phase, and the treatment has only been used on a few patients, but the results have been promising so far.
Since 2006, the Cancer Genome Atlas project has been cataloging the genetic changes in more than 20 cancers, with glioblastoma being a top priority. This information will help to improve the diagnosis and treatment, and potentially prevent, brain cancer.