Brain and Spinal Tumors
Tumors are abnormal tissue growth caused by cells that grow out of control. Brain and spine tumors can start in the brain or spine itself, called primary tumors. They can also spread from other parts of your body through your bloodstream, called metastatic tumors.
Brain and spine tumors are rare, and some subtypes are extremely rare. About 79,000 people in the US are diagnosed with a central nervous system (brain or spinal) tumor each year, according to the American Cancer Society. About 25,000 people will have cancerous tumors. Only about 1% of the population will have a brain tumor in their lifetime.
The most common types of brain tumors are metastatic and require the expertise of a team of doctors to find the best treatment plan. The most common cancers that spread to the brain are lung cancer, breast cancer, melanoma, and colon cancer, but other cancers can also spread to the brain.
Spine tumors can compress the spinal cord and or spinal nerves, making treating them serious and complex. Each should be evaluated by experienced neurosurgeons and oncologists at a major medical center.
Brain and spinal tumors are either benign or malignant (cancerous).
Benign tumors grow in place and do not invade surrounding tissue. They may need to be removed due to their size and location if they are pressing on nearby tissues or causing symptoms similar to malignant tumors. Though they may require ongoing surveillance, once removed, they usually don’t come back.
Malignant tumors usually grow fast and invade surrounding tissue. They require treatment and close monitoring. Malignant tumors originating from the brain and spinal cord rarely spread to other areas of your body, but they can come back after treatment. Metastases are also considered malignant.
Types of Brain Tumors
According to the World Health Organization, there are more than 120 types of central nervous system tumors.
Gliomas are the most common type of primary brain tumor in adults. They originate from glial cells, which support the nerves in your brain and spine. There are several types of glioma and are categorized based on what glial cell type they originated from and how malignant they are.
Glioblastoma is the most common and most malignant type of glioma. They can grow quickly and invade nearby areas. About 14,000 people in the US are diagnosed each year.
Meningioma is the most common adult benign brain tumor and can be found in different parts of the brain. Most meningiomas are slow growing and low grade, however, some meningiomas can be more aggressive, such as atypical or anaplastic meningiomas. If a meningioma is located near a critical structure, such as the optic nerves or the brainstem, it may eventually grow and cause potential symptoms including vision changes, weakness, or numbness.
Pituitary adenoma is a benign tumor on the pituitary gland, which is found at the base of the brain. The Pituitary gland is responsible for the regulation of the hormone's levels in the body. These tumors may impact quality of life due to inducing pressure on nearby structures of the brain or affecting hormone production. There are two different types of pituitary tumors (adenomas): secretory and non-secretory. Secretory pituitary tumors secrete in excess one or more hormones, whereas non-secretory pituitary tumors do not secrete hormones. Non-secretory adenomas are the most commonly diagnosed.
Craniopharynigoma is a rare, benign tumor that forms close to the pituitary gland. These tumors typically develop in children, although they can be found in adults. Craniopharyngiomas can exert pressure that can affect other structures of the brain responsible for vision and growth, or hormone production.
Acoustic neuroma, also known as vestibular schwannoma, is a slow growing, benign tumor that develops on the vestibular nerve, which leads from the inner ear to the brain. This nerve helps with your hearing and balance. Therefore, the pressure from acoustic neuroma on this nerve can cause hearing loss and unsteadiness.
Pineal tumors form in the pineal gland of your brain. This gland is responsible for regulation and production of the hormone melatonin. These types of tumors are rare. They are most often found within children and teenagers. Pineal tumors can be malignant or benign.
Types of Spine Tumors
We categorize spine tumors into three groups:
Vertebral column tumors
Most tumors involving the bones and cartilage cells in your vertebral column have spread (metastasized) from another area of your body, usually through your bloodstream. In women, most tumors have spread from the breast or lung. In men, most tumors have spread from the prostate or lung.
Occasionally vertebral column tumors start in your spine. Benign tumor types include osteoid osteoma, osteoblastoma, and giant cell tumors. Malignant tumor types include chondrosarcoma and Ewing’s sarcoma.
These tumors arise from the dura, a thick three-layer membrane that surrounds your spinal fluid and spinal cord. Most are benign meningiomas and nerve sheath tumors--schwannomas and neurofibromas.
These tumors come from the supporting cells in your spinal cord. Most of these tumors are astrocytomas (more common in children) or ependymomas (more common in adults). Blood vessel tumors, called hemangioblastomas, can also start here and are usually associated with an inherited condition called von Hippel-Lindau disease.
Most brain tumors occur in people without any known risk factors. The vast majority are not related to known genetic, environmental, or lifestyle factors. Most of these tumors are caused by cancer spreading from other sites in your body, or by alterations in the genes that control brain cell growth. Known risk factors include the following, though these account for a small fraction of patients:
- Genetic conditions. Some people with genetic conditions like neurofibromatosis, von Hippel-Lindau disease, Li-Fraumeni syndrome, and retinoblastoma are at high risk. Occasionally people in the same family who don’t have these syndromes may develop brain and spine tumors. Schwannomas may also have a genetic trigger.
- Radiation therapy. People who have had radiation therapy to the head to treat other cancers have an increased risk of brain and spinal tumors.
- Family history. Most people with brain tumors do not have a family history of the disease. In rare cases, brain or spinal tumors can run in families.
- Weak immune system. People who have a weak immune system have a higher risk of developing a central nervous system (CNS) lymphoma. This includes people who have AIDS or who have had an organ transplant.
Each person may experience the symptoms of brain and spinal tumors differently. Symptoms can also vary based on the tumor’s location in the brain, size and growth rate. Many of the symptoms associated with brain cancer may also be common to other conditions. Therefore, it is important to meet with your doctor if you are concerned about your symptoms relating to brain cancer.
Brain Tumor Symptoms
- Vomiting and nausea
- Headaches, that are noticeably worse when laying down
- Personality or mood changes, such as irritability and depression
- Visual changes and vision loss
- Problems with speech, understanding speech, or writing
- Weakness or loss of use of one side of your body
- Difficulty walking or problems with balance
- Hearing loss
Spinal Tumor Symptoms
Back pain that doesn’t improve with rest is the most common symptom of a spine tumor. Most back pain is not caused by a tumor. However, if you have a history of cancer, it’s important to seek medical attention for back pain because it’s common for other cancers to spread to your spine.
You might also experience:
- Sciatica, or pain that radiates from your lower back, down your buttocks and back of your leg
- Numbness in your legs, arms or chest
- Difficulty walking
- Scoliosis, or curvature of the spine resulting from a spine-deforming tumor
- Impaired bladder or bowel function
If you have impaired bladder or bowel function or paralysis, seek treatment immediately.
Screening and Diagnosis
If you have symptoms of a brain or spinal tumor, getting a diagnosis is urgent. The source of the tumor, the total number of lesions and whether the tumor is malignant or benign will determine your prognosis and treatment.
To start, your doctor will take your medical history and do a physical exam. They’ll also do a neurological exam to evaluate your eye movements, hearing, sensation, motor function, swallowing, balance, and coordination.
Should you need further screening, your doctor may order:
- MRI (magnetic resonance imaging). Uses powerful magnetic fields to create 3D pictures that detect tumors with greater detail.
- CT (computed tomography). Takes data from several X-ray images and converts them into pictures on a monitor. It can show tissues and blood vessels in addition to bones.
- Lumbar puncture. May be recommended by your doctor in order to examine the cerebrospinal fluid (CSF). This fluid would be tested for the presence of viruses, bacteria, or tumor cells.
Depending on which type of tumor your doctor suspects, you might have additional tests and procedures.
- Cerebral angiogram. A minimally invasive procedure that takes a picture of the tumor’s blood vessels.
- Chest X-ray. Discovers if the tumor started elsewhere in your body.
- Bone scan. Detect tumors and bone abnormalities.
- Myelogram. An X-ray or CT scan with an injection of contrast dye to highlight your nervous system.
- Spinal tap. Draws a small amount of cerebrospinal fluid from your spine. A pathologist will examine the fluid under a microscope to look for infection, cancer cells, or other problems.
- Blood draw. Check for tumor markers that indicated a particular tumor type.
- PET scan (positron emission tomography). Uses a small amount of radioactive glucose, injected into your vein, to show where glucose is being used in your body. A scanner rotates around your body to create an overall picture. Cancer cells use more glucose than normal cells do.
- Magnetic resonance spectroscopy (MRS). Produces images depicting your brain’s chemistry and function. Your doctor will compare normal tissue to abnormal tissue. This procedure uses the same equipment as an MRI so they’re often done at the same time.
- Functional MRI. Used to determine which areas of the brain are responsible for important functions such as speech and movement. Your surgeon may request this test to give them a better understanding of where your tumor is in relation to these important parts of your brain. This will help them maximize tumor removal while preserving your function.
- Biopsy. A tissue sample taken before or during surgery to confirm diagnosis.