A Quick Guide to Understanding Brain Tumors

The world of brain tumors is anything but simple, starting with the fact that there are about 100 different types of primary brain tumors. And each type of brain tumor can come with its own set of symptoms.

While this makes it hard to describe brain tumors in a single blog, board-certified neurologist Dr. Paul Gill and our team at Gill Neuroscience present a few key points that provide a good introduction to the complex world of brain tumors.

What are brain tumors?

First, we want to narrow this discussion to primary benign and malignant brain tumors and not secondary tumors, which are often metastases of other cancers that have spread. 

Primary brain tumors, like other cancers and benign growths, are abnormal masses due to cells that multiply excessively. If these cells are cancerous, the tumor is malignant. If they’re just abnormal growths without the presence of cancerous cells, we classify them as benign.

Thankfully, nearly three-quarters of primary brain tumors are benign, or noncancerous.

As we mentioned, there are more than 100 different types of brain tumors, including:

• Meningiomas, accounting for 30% of brain tumors and develop in outer brain tissues
• Pituitary adenomas, which develop in the pituitary gland
• Craniopharyngiomas, which often develop near the pituitary gland
• Acoustic neuromas, which grow in the nerves that connect your ears to your brain
• Hemangioblastomas, which grow on blood vessels in your brain

Again, there are plenty others, but these represent some of the more common types of brain tumors. 

Brain tumors are relatively rare

In 2026, experts predict that slightly more than 108,000 Americans will develop a primary brain tumor, which includes nearly 25,000 malignant brain and spinal cord tumors.

According to the American Cancer Society, brain and spinal cord tumors account for only 1% of cancers diagnosed in the United States, and the lifetime risk for this type of cancer is also 1%.

Brain tumors affect adults most often

While kids can have brain tumors, 90% of brain tumors are found in adults. The average age of diagnosis is in the early 60s.

Signs of a potential brain tumor

It’s challenging to provide a list of symptoms of brain tumors, as symptoms can vary widely depending on which area of the brain it’s impacting. That said, there are often some crossover symptoms, which include:

• Headaches that show no sign of improving or going away
• Dizziness
• Nausea and vomiting
• Vision issues, such as blurry vision
• Seizures
• Problems with balance
• Fatigue and sleepiness
• Behavior changes (you’re not behaving “normally”)
• Personality changes

It’s safe to say that if you're experiencing any of the symptoms above for no apparent reason, we want to see you for an evaluation.

Evaluating brain tumors

To figure out what’s causing your symptoms, we review them in detail, and then we figure out the next step, which typically involves an MRI. With an MRI, we get a glimpse inside your head to see whether there’s a tumor and, if so, the location and extent of the growth.

If we find a growth, we also typically arrange for a biopsy so we can see what sort of cells we’re dealing with and whether the tumor is benign or malignant.

From there, treatment depends entirely on what we find, your symptoms, and your medical history, but we’re getting ahead of ourselves here.

Let’s step back and point out that if you’re experiencing strange symptoms or you have more questions about brain tumors, call our Houston, Texas, office at 832-912-7777, or use our online form to request an appointment.