Last Updated on December 1, 2025 by Bilal Hasdemir

Understanding brain tumors is essential for effective treatment.

A brain tumor is an abnormal growth of cells in the brain. These tumors can be benign, meaning non-cancerous, or malignant, meaning cancerous. The four main types of brain tumors are classified based on their origin and behavior. Our essential guide to the main types of brain tumors. Learn the critical, awful differences between gliomas, meningiomas, and more.

Key Takeaways

• Brain tumors can be benign or malignant.
• The classification of brain tumors is based on their origin and behavior.
• Understanding the type of tumor is critical for treatment.
• There are four main types of brain tumors.
• Diagnosis and treatment vary based on the tumor type.

Understanding Brain Tumors: An Overview

A brain tumor is an abnormal mass of tissue in the brain. It can be benign or malignant. Understanding brain tumors is essential for effective treatment. Brain tumors can really affect a person’s life, so it’s important to understand them well.

Definition and Basic Concepts

A brain tumor is when cells in the brain grow out of control. This growth can be benign, or non-cancerous, or malignant, or cancerous. Benign tumors usually don’t spread, but malignant ones can.

 Knowing the basics is the first step to learning more about them.

Prevalence and Statistics in the United States

Brain tumors are not common, making up about 1% of all cancers in the U.S. 

There’s a big need for more research on brain tumors. The

“National Cancer Institute’s data show brain tumor rates have stayed the same for years. But there’s a lot we don’t know about them.”

Looking at brain tumor stats helps us understand the issue better. For example, the Central Brain Tumor Registry of the United States (CBTRUS) gives us important data. This data helps us see how brain tumors affect health.

Benign vs. Malignant Brain Tumors

It’s important to know the difference between benign and malignant brain tumors. This helps decide the best treatment. Both types can affect a person’s health and life quality.

Characteristics of Benign Tumors

Benign brain tumors grow slowly and are not cancerous. They don’t spread to other brain areas, making them easier to remove. But, they can press on nearby parts.

Benign brain tumors have a few key traits:

• Slow growth rate
• Clear boundaries
• Non-invasive nature

Characteristics of Malignant Tumors

Malignant brain tumors grow fast and are cancerous. They can spread to other brain areas, making treatment hard. These tumors can start in the brain or come from other places.

Here are some main traits of malignant brain tumors:

• Rapid growth rate
• Invasive nature
• Potential to spread to other parts of the brain or central nervous system

Understanding brain tumors is essential for effective treatment.

Primary vs. Secondary Brain Tumors

Brain tumors are either primary or secondary. This depends on where they start. Knowing this helps doctors understand the tumor better and choose the right treatment.

Originating in the Brain

Primary brain tumors start in the brain. They can come from different types of cells. These tumors can be either benign or malignant. They grow at different rates and can cause various levels of harm.

The National Cancer Institute says primary brain tumors are rare. They make up about 2% of all new cancer cases in adults.

The most common primary brain tumors are gliomas, meningiomas, and pituitary tumors. Gliomas are the most common type. They can be low-grade or high-grade. Meningiomas are usually benign and come from the meninges, which protect the brain and spinal cord.

Metastasized from Other Organs

Secondary brain tumors, or metastatic brain tumors, spread to the brain from other cancers. Common cancers that spread to the brain include lung, breast, melanoma, colon, and kidney cancers. These tumors are malignant and can greatly affect a patient’s outlook.

When a brain tumor is secondary, it usually means the cancer is advanced. Treating these tumors often involves surgery, radiation, and chemotherapy. The treatment plan is made based on the patient’s condition and the type of cancer.

It’s important to know if a brain tumor is primary or secondary. This helps doctors choose the best treatment. It also gives patients accurate information about their chances of recovery.

The Four Main Types of Brain Tumors

It’s key to know the different types of brain tumors for diagnosis and treatment. These tumors fall into four main categories based on their features and where they start.

Classification Systems

Classification systems for brain tumors help doctors figure out what kind of tumor it is. They look at how aggressive the tumor is and its characteristics. The most common system uses the tumor’s look under a microscope and its genes.

Classification Criteria:

• Tumor origin
• Histological features
• Genetic characteristics
• Growth patterns

World Health Organization (WHO) Grading System

The WHO grading system is a key way to rate brain tumors by how aggressive they are. Tumors are ranked from I to IV. Grade I is the least aggressive, and Grade IV is the most aggressive.

WHO Grade	Description	Characteristics
I	Low-grade, benign	Slow-growing, less aggressive
II	Low-grade, potentially malignant	More cellular than Grade I, potentially invasive
III	High-grade, malignant	More aggressive, mitotically active, and potentially anaplastic
IV	High-grade, highly malignant	Highly aggressive, necrotic, and microvascular proliferation

The WHO grading system helps doctors and researchers talk about brain tumors in a clear way. It makes it easier to understand the tumor’s characteristics and what to expect.

Type 1: Gliomas

Gliomas start from glial cells and are a big part of primary brain tumors. They come in many types, depending on the glial cell they begin with.

Astrocytomas

Astrocytomas start from astrocytes, a certain glial cell. They can be low-grade (less aggressive) or high-grade (more aggressive). Low-grade astrocytomas grow slowly and might just need regular checks. High-grade astrocytomas grow fast and need quick treatment.

Oligodendrogliomas

Oligodendrogliomas come from oligodendrocytes, another glial cell type. They’re rare but often have a better outlook than astrocytomas. Treatment usually includes surgery, and sometimes chemo or radiation.

Ependymomas

Ependymomas start from ependymal cells in the brain’s ventricles and spinal cord. They can happen at any age and vary in how aggressive they are. Treatment often means surgery, and sometimes radiation.

Glioblastoma Multiforme (GBM)

Glioblastoma multiforme is the most aggressive glioma. It grows fast and often comes back. Treatment usually combines surgery, radiation, and chemo.

The table below shows the main features of different gliomas:

Type of Glioma	Cell of Origin	Aggressiveness	Typical Treatment
Astrocytoma	Astrocyte	Low to High	Surgery, Radiation, Chemotherapy
Oligodendroglioma	Oligodendrocyte	Low to Moderate	Surgery, Chemotherapy, Radiation
Ependymoma	Ependymal cell	Variable	Surgery, Radiation
Glioblastoma Multiforme	Astrocyte	High	Surgery, Radiation, Chemotherapy

Knowing the different gliomas is key to finding the right treatment. Each type has its own traits and outlook, and treatment plans are made to fit.

Type 2: Meningiomas

Meningiomas are tumors that grow from the meninges. These are protective membranes around the brain and spinal cord. Most meningiomas are not cancerous and can affect people differently.

Characteristics and Location

Meningiomas usually start near the brain’s surface. They can grow in many places, like around the brain’s outer parts or the spinal canal. Where a meningioma grows affects its symptoms and how hard it is to remove surgically.

Symptoms can vary a lot. They might include headaches, seizures, or problems with brain function. This depends on the tumor’s size and where it is.

Subtypes and Grades

Meningiomas are divided into subtypes and grades. The World Health Organization (WHO) grading system is used. It has three grades: Grade I (benign), Grade II (atypical), and Grade III (anaplastic or malignant).

Most meningiomas are Grade I, which means they are less likely to come back. But, higher-grade tumors are more aggressive and might need more treatment.

There are different types of meningiomas, like meningothelial, fibrous, and transitional. Knowing the exact type and grade helps doctors choose the best treatment. This might include surgery, radiation, or watching the tumor closely.

Type3: Pituitary Tumors

Pituitary adenomas are tumors in the pituitary gland. This gland controls many body functions through hormones. These tumors can change hormone levels, affecting health.

Functioning vs. Non-functioning Pituitary Adenomas

Pituitary adenomas are divided into two types: functioning and non-functioning. Functioning adenomas make too much hormone, causing health problems. For example, too much prolactin can disrupt menstrual cycles in women and cause erectile dysfunction in men.

Non-functioning adenomas don’t make hormones but can press on nerves and other parts of the gland. This can cause symptoms.

It’s important to know the difference for treatment. Functioning adenomas show symptoms of hormonal imbalance. Non-functioning adenomas might not show symptoms until they grow big enough to affect nerves.

Impact on Hormonal Balance

Pituitary adenomas can greatly affect hormone levels. Functioning adenomas can lead to too much of certain hormones. This can cause symptoms like excessive growth in acromegaly or weight gain in Cushing’s disease.

Type of Adenoma	Hormone Produced	Symptoms
Prolactinoma	Prolactin	Irregular menstrual periods, erectile dysfunction, galactorrhea
Growth Hormone-Secreting Adenoma	Growth Hormone	Acromegaly (excessive growth of hands, feet, and facial features)
ACTH-Secreting Adenoma	ACTH	Cushing’s disease (weight gain, high blood pressure, mood changes)

Treatment for pituitary adenomas depends on their type, size, and health impact. Knowing about these tumors helps in making good treatment plans.

Type4: Schwannomas (Acoustic Neuromas)

Acoustic neuromas, or schwannomas, are non-cancerous tumors. They come from Schwann cells, which keep the nerve sheath healthy. These tumors are usually benign and grow slowly. They often affect balance and hearing.

Development and Growth Patterns

Schwannomas usually grow on the vestibular nerve, which helps with balance. Their growth can vary. Some grow slowly and may not cause problems for years. Others grow faster and can press on nerves, leading to symptoms.

The exact cause of schwannomas is not known. But they are linked to genetic conditions like Neurofibromatosis Type 2 (NF2). Scientists are working to understand how these tumors develop.

Impact on Hearing and Balance

As schwannomas grow, they can harm nearby nerves. This can cause hearing loss, tinnitus (ringing in the ears), and balance problems. The severity of these symptoms depends on the tumor’s size and location.

In some cases, schwannomas can severely impair hearing or balance. This can make daily activities hard. It’s important to catch these tumors early and monitor them closely.

Treatment for schwannomas includes watching them with MRI scans, surgery, or radiation therapy. The choice depends on the tumor’s size, growth rate, and the patient’s health.

Less Common Types of Brain Tumors

Brain tumors like medulloblastomas and craniopharyngiomas are not as common. They are challenging to diagnose and treat. These tumors affect patients’ lives and add complexity to medical care.

Medulloblastomas

Medulloblastomas are aggressive tumors found mainly in children. They spread through the cerebrospinal fluid. Treatment includes surgery, radiation, and chemotherapy.

Characteristics of Medulloblastomas:

• Most commonly found in the cerebellum
• High propensity to disseminate through the CSF
• Often require multimodal treatment approaches

Craniopharyngiomas

Craniopharyngiomas are benign tumors near the pituitary gland and hypothalamus. They can cause serious problems because of their location. This can affect hormones and brain function.

Management of Craniopharyngiomas:

Treatment Approach	Description	Outcomes
Surgical Resection	Primary treatment aiming for total removal	Can be curative if total resection is achieved
Radiation Therapy	Used for residual or recurrent tumors	Effective in controlling tumor growth
Combination Therapy	Mix of surgery and radiation	Offers optimal outcomes in complex cases

Lymphomas of the Brain

Lymphomas of the brain are rare and can be primary or secondary. They are more common in people with weakened immune systems. Treatment includes chemotherapy and radiation.

Key Features of Brain Lymphomas:

• Often associated with Epstein-Barr virus in immunocompromised patients
• Can present with non-specific symptoms like headache and confusion
• Require prompt diagnosis and treatment

Common Symptoms of Brain Tumors

It’s important to know the symptoms of brain tumors early. This helps in getting the right treatment. Brain tumors can show different symptoms based on their type, size, and where they are in the brain.

General Symptoms

Common symptoms include headaches, seizures, and changes in thinking. Morning headaches are often worse and can make you feel sick. Seizures happen when the tumor presses on the brain. Thinking problems, like memory loss, can also occur.

Headaches are common in brain tumor patients, affecting about 50%. “The headache is typically worse in the morning and may improve throughout the day.” Thinking changes can make simple tasks hard.

Location-Specific Symptoms

The brain area affected by a tumor can change symptoms. Tumors in the frontal lobe can affect personality and decision-making. Tumors in the cerebellum can cause balance issues.

A study found that

“Tumors located in the frontal lobe can result in significant cognitive and behavioral changes.”

Knowing where the tumor is can help doctors diagnose it.

Symptoms by Tumor Type

Different tumors have unique symptoms. For example, gliomas can cause various symptoms based on their grade and location. Meningiomas can cause headaches and seizures if they grow big enough.

When to Seek Medical Attention

If you have symptoms that could be from a brain tumor, see a doctor. Early treatment can greatly improve your chances of recovery.

If you have new or worsening headaches, seizures, or thinking changes, see a doctor. They can check you and suggest tests.

Diagnosis and Imaging Techniques

Diagnosing brain tumors is a detailed process. It uses neurological exams and advanced imaging. Getting the diagnosis right is key to choosing the right treatment and improving patient care.

Neurological Examination

A neurological exam is often the first step. It checks how well the brain works. Doctors look for signs like muscle weakness and vision changes.

Magnetic Resonance Imaging (MRI)

MRI is a top choice for finding brain tumors. It shows the brain’s details, helping doctors see where the tumor is and how big it is. MRI also helps tell different tumors apart.

Computed Tomography (CT) Scans

CT scans are also used to find brain tumors. They show the brain in slices, helping doctors see tumors and how they affect the brain. CT scans are great in emergencies.

Biopsy Procedures

A biopsy takes a piece of the tumor for testing. It’s key to confirm the diagnosis and know the tumor’s type and grade. The biopsy results help decide treatment and give insight into the future.

Diagnostic Technique	Description	Key Benefits
Neurological Examination	Assessment of neurological functions	Identifies signs of neurological impairment
MRI	Detailed imaging of brain structures	Provides detailed images of tumor location and characteristics
CT Scans	Cross-sectional imaging of the brain	Useful in emergency situations, quick assessment
Biopsy	Removal of tumor tissue for examination	Confirms diagnosis, determines tumor type and grade

Using these methods together makes diagnosing brain tumors more accurate. This helps doctors create treatment plans that fit each patient’s needs.

Treatment Options for Brain Tumors

There are many ways to treat brain tumors. Each treatment is chosen based on the tumor’s type, size, and where it is. The patient’s health also plays a big role.

Surgical Approaches

Surgery is often the first step in treating brain tumors. The goal is to remove as much of the tumor as possible. Advances in surgical techniques have made surgery safer and more effective.

In some cases, surgery might not be possible. This could be because of where the tumor is or the patient’s health. Then, other treatments are considered.

Radiation Therapy

Radiation therapy is used for many brain tumors. It’s often chosen when surgery isn’t an option. External beam radiation therapy is the most common type. Stereotactic radiosurgery is used for small, well-defined tumors.

Chemotherapy

Chemotherapy uses drugs to kill tumor cells. It can be taken by mouth or through an IV. Temozolomide is a common chemotherapy drug for certain brain tumors, like glioblastoma.

Targeted Therapy

Targeted therapy is a newer method. It uses drugs that target specific molecules in tumor cells. Bevacizumab is a targeted therapy drug used for glioblastoma that comes back.

Brain tumor treatment often combines different approaches. This is tailored to each patient’s needs. New medical technologies and research are always improving treatment options for brain tumors.

Conclusion

Brain tumors are complex and varied. They come in different types, each with its own challenges and characteristics. The main types include gliomas, meningiomas, pituitary tumors, and schwannomas.

Gliomas start in the brain and can range from low-grade to very aggressive. Meningiomas are usually benign and might need surgery or just watching. Pituitary tumors can mess with hormones, and schwannomas can affect hearing and balance.

Understanding brain tumors is essential for effective treatment.

In short, dealing with brain tumors needs a detailed approach. By understanding the various types, people can better manage their care and options.

FAQ

References

National Center for Biotechnology Information. Evidence-Based Medical Insight. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8328013/