Causes and Risk Factors of Brain Cancer

Brain cancer happens when cells that should not be there grow in your brain. Tumors are made by cancer cells, and depending on the type of tumor, they can grow slowly or quickly.

This blog will provide an overview of brain cancer and the many causes and risk factors associated with the disease.

What is Brain Cancer?

Primary brain cancer, which is also just called “brain cancer,” is when too many cells grow in your brain and form lumps called “tumors.” This is different from secondary, or metastasized brain cancer, which starts in another part of your body and spreads to your brain. 

Some types of cancerous brain tumors can grow very quickly, and the way your body works can be interrupted by these cancerous tumors. Brain tumors can be dangerous and should be treated as soon as they are found. Brain cancer is quite uncommon; the American Cancer Society says that people have a less than 1% chance of getting a cancerous brain tumor in their lifetime.

What are the Symptoms of Brain Cancer?

The signs and symptoms of brain cancer depend on how big the brain tumor is and where it is. In its early stages, brain cancer has many of the same symptoms as many less serious conditions.

Many of these signs are very common and probably don’t mean you have brain cancer. But if you’ve had any of these symptoms for more than a week, if they came on suddenly, if over-the-counter pain medications don’t help, or if you’re worried about any of them, you should see your doctor. Common brain cancer symptoms include:

  • Headaches that are usually worse in the morning
  • Nausea
  • Vomiting
  • A lack of coordination
  • A lack of balance
  • Difficulty walking
  • Memory lapses
  • Difficulty thinking
  • Trouble with speech
  • Trouble with vision
  • Personality changes
  • Abnormal eye movements
  • Muscle jerking
  • Muscle twitching
  • Unexplained passing out, or syncope
  • Drowsiness
  • Numbness or tingling in the arms or legs
  • Seizures

Brain Tumor vs. Brain Cancer

All brain cancers are tumors, but not all brain tumors are cancerous. Noncancerous brain tumors are called benign brain tumors.

Most benign brain tumors grow slowly, have clear edges, and don’t spread. Even benign tumors can be harmful as they can hurt and squeeze parts of the brain, which can lead to severe problems. If a benign brain tumor grows in an important part of the brain, it can be fatal. A benign tumor rarely turns into a cancerous one. Meningioma, vestibular schwannoma, and pituitary adenoma are all examples of tumors that are benign.

Malignant brain tumors are cancerous. Most of the time, they grow quickly and take over healthy brain structures nearby. Brain cancer can be life-threatening because it changes the brain’s most important parts, and malignant tumors can start in or near the brain. Some examples are medulloblastoma, chondrosarcoma, and olfactory neuroblastoma.

Types of Brain Tumors

Brain tumors are named based on the location in the brain or upper spine they are in. Tumors are also given a grade where the grade of a tumor shows how quickly it is likely to grow. The grades range from 1 to 4, with 1 being the slowest and 4 being the fastest.

Some of the most common primary types of brain tumors include:

  • Glioma – Gliomas are brain tumors that originate in the glial cells, and account for about 3 out of 10 cases of brain cancer
  • Astrocytoma – Astrocytomas are a type of glioma that include glioblastomas, the fast-growing type of brain tumor
  • Meningioma – Often benign and slow-growing, meningioma tumors grow in the tissue that surrounds your brain and spinal cord and are the most common type of brain tumor in adults
  • Ganglioglioma – Gangliogliomas are slow-growing tumors found in the neurons and glial cells that can normally be treated with surgery
  • Craniopharyngiomas – Craniopharyngiomas are slow-growing tumors that form between the pituitary gland and the brain and often press on optic nerves, resulting in vision difficulties
  • Schwannomas – Schwannomas are slow-growing tumors that form around the cranial nerves and are almost always benign
  • Medulloblastoma – Medulloblastomas are fast-growing tumors that form on the brain’s nerve cells and are more common in children

In adults, secondary brain tumors are far more common than primary brain tumors. Any cancer can spread to the brain, but common types include:

  • Breast cancer
  • Colon cancer
  • Kidney cancer
  • Lung cancer
  • Melanoma

Causes and Risk Factors for Brain Cancer

No one knows for sure what causes primary brain cancer, but studies have shown that high doses of ionizing radiation increase the risk of brain cancer. Most ionizing radiation comes from medical imaging tests like CT scans and X-rays, radiation therapy treatments, and possible exposure in the workplace.

Several risk factors can make a person more likely to get brain or spinal cord tumors. Some things that put people at risk for brain cancer are:

  • Radiation exposure
  • Genetics
  • Weakened immune system 
  • Weakened immune system 
  • Exposure to pesticides, herbicides, and fertilizer
  • Exposure to things like lead, plastic, rubber, oil, and some types of fabrics
  • A history of brain tumors in the family

That doesn’t mean that people with one or more of these traits will get cancer and many people have more than one of these traits and are perfectly healthy. Also, people who have no known risk factors for brain tumors can still get them. Most of the time, risk factors are used to figure out who should keep a close eye on their health and tell a doctor about any possible signs of brain cancer.

Secondary brain cancer, the type of brain cancer that occurs when cancer that began in another part of your body spreads to your brain, is more likely to be caused by some types of cancer than others.


Here at Clearview Cancer Institute, our specialists are here to support you in whatever you need. Click here to view our locations page to find our nearest location to you. Call us at 888-374-1015 to set up your consultation with us.