A brain tumor is growth of abnormal cells in your brain.
There are many types of brain tumors. Some brain tumors are non-cancerous (benign) while some are cancerous (malignant). Brain tumors can start in your brain (primary brain tumors), or cancer can start in other body parts and spread to your brain (secondary or metastatic brain tumors).
The rate at which a brain tumor grows can vary widely. The location as well as the rate of growth of a brain tumor determines the affect on nervous system functioning.
Brain tumor treatment options depend on the brain tumor type you have, as well as its location and size.
The signs and symptoms of a brain tumor vary widely and depend on the size, location, and rate of growth of the brain tumor.
General signs and symptoms caused by brain tumors can include:
- New onset or change in headache pattern
- Headaches that gradually become more frequent and severe
- Unexplained nausea or vomiting
- Vision problems, like blurred vision, double vision, or peripheral vision loss
- Gradual loss of feeling or movement in one arm or leg
- Difficulty of balance
- Speech disorders
- Confusion in daily affairs
- Personality or behavior changes
- Seizures, especially in a person who has no seizures history
- Hearing problems
When to see a doctor
See your doctor if you have any persistent signs and symptoms that concern you.
Also Read: Extra Body Fat Can Lead To Brain Shrinkage
Brain tumors that start in the brain
In the brain, primary brain tumors originate itself or in tissues close to it, such as the cranial nerves, membranes covering the brain (meninges), pineal or pituitary gland.
Primary brain tumors start when normal cells acquire mutations in their DNA. These mutations allow cells to grow and divide at increased rates and continue to live after healthy cells die. The result is a mass of abnormal cells, which takes form of a tumor.
Primary brain tumors are much less common than secondary brain tumors in adults, in which the cancer starts elsewhere and spreads to the brain.
Primary brain tumors are of many different types. Each gets its name from the cells type involved. Examples include:
- Gliomas. These tumors start in the brain or spinal cord and also include astrocytomas, ependymomas, glioblastomas, oligoastrocytomas, and oligodendrogliomas.
- Meningiomas. A meningioma is a tumor that starts from the membranes that surround brain and spinal cord (meninges). Most meningiomas are not cancerous.
- Acoustic neuromas (schwannomas). These are benign tumors that grow on the nerves responsible to control balance and hearing leading from your inner ear to the brain.
- Pituitary adenomas. Most of them are benign tumors that develop in the pituitary gland at the base of the brain. These tumors can affect pituitary hormones with throughout effects in the body.
- Medulloblastomas. In children, these are the most common cancerous brain tumors. A medulloblastoma starts in the lower back part of the brain and tends to spread into the cerebrospinal fluid. In adults, these tumors are less common, but they do occur.
- Germ cell tumors. Germ cell tumors can develop during childhood when the testes or ovaries will form. But sometimes germ cell tumors affect other body parts, such as the brain.
- Craniopharyngiomas. These rare, non-cancerous tumors start near the pituitary gland of the brain, which secretes hormones that control many bodily functions. As the craniopharyngioma grows slowly, it can affect the pituitary gland and other nearby brain structures.
Cancer that spreads to the brain by starting elsewhere
Secondary (metastatic) brain tumors are tumors that starts elsewhere in your body and then spreads (metastasizes) to your brain.
Secondary brain tumors most often occur in people with a history of cancer. But in rare cases, a metastatic brain tumor can be the first sign of cancer that has started elsewhere in your body.
In adults, more common are secondary brain tumors than primary brain tumors.
To the brain, any cancer can spread but common types include:
- Breast cancer
- Colon Cancer
- Kidney cancer
- Lung cancer
The cause of the tumor is not clear in most people with primary brain tumors. But doctors have identified certain factors that may increase your risk for a brain tumor.
Risk factors include:
- Exposure to radiation. People have an increased risk of brain tumor who have been exposed to a type of radiation called ionizing radiation. Examples of ionizing radiation include radiation therapy used to treat cancer and exposure to atomic bombs radiation.
- Family history of brain tumors. In people, a small portion of brain tumors occur who have a family history or a family history of genetic syndromes that increase the brain tumors risk.
Your doctor may recommend a number of tests and procedures if you are suspected of having a brain tumor, including:
- A neurological exam. A neurological exam may include, checking your balance, coordination, hearing, reflexes, strength, and vision.
- Imaging tests. Magnetic resonance imaging (MRI) is usually used to help diagnose brain tumors. In some cases, a dye may be injected into a vein in your arm during your MRI study.
A number of specialized components in MRI – including functional MRI, perfusion MRI, and magnetic resonance spectroscopy – can help your doctor assess the tumor and plan treatment.
Sometimes other imaging tests are preferred, including computerized tomography (CT). Positron emission tomography (PET) can be used for brain imaging, but is generally not as useful for creating images of brain cancer as it is for other types of cancer.
- Tests to find cancer in other body parts. An example might be a CT scan or a PET scan to look for signs of lung cancer.
- Collect and test a sample of abnormal tissue (biopsy). A biopsy can be done as part of an operation to remove the brain tumor, or a biopsy can be done using a needle.
A stereotaxic needle biopsy may be done for brain tumors in hard to reach areas or very sensitive areas of your brain that could be damaged by a larger operation. In your skull, your neurosurgeon drills a small hole. A fine needle is then inserted through the hole. The tissue is removed using the needle, which is often guided by CT or MRI scans.
The biopsy sample is then examined under a microscope to determine if it is cancerous or benign. Your doctor can get a clue from sophisticated lab tests about your prognosis and treatment options.
At the Mayo Clinic, teams of experts use all of these diagnostic techniques, in addition to cutting-edge imaging technology like a high-power MRI scanner (7 tesla) and magnetic resonance elastography (MRE). The MRE tests the smoothness of a tumor so that a neurosurgeon can plan the best way to remove it. This technology was developed by a physician-scientist from the Mayo Clinic.
The Mayo Clinic Brain Tumor Team also uses molecular diagnostics which is an individualized medical approach that analyzes the DNA of a tumor. This type of genetic test helps doctors predict which treatment options will work on specific types of brain tumors.