Rare Brain Tumors: Gangliocytoma & Pineocytoma


What are gangliocytomas and pineocytomas?

Gangliocytoma and pineocytoma are rare, benign brain tumors. Gangliocytoma tumors affect parts of your central nervous system (CNS). Pineocytoma tumors form in your pineal gland, a small organ located deep in your brain that controls sleep. These are slow-growing tumors that healthcare providers typically treat with surgery and radiation therapy.

Who’s affected by these brain tumors?

People of any age may have gangliocytoma, but this type of brain tumor develops most often in people between the ages of 10 and 30. Pineocytomas typically affect adults ages 20 to 64, and the average age at diagnosis is 38 years.

What parts of my CNS are affected by gangliocytomas?

Gangliocytomas most often form in your brain’s temporal lobes, which sit behind your ears. Your temporal lobes process sensory input, including memory, hearing and emotion. The tumor may also form in your:

  • Brainstem: This is the part of your brain that connects your cerebrum (uppermost portion), to your spinal cord and cerebellum. It sends signals to control things like breathing and heart rate.
  • Cerebellum: Located at the back of your brain, your cerebellum controls balance, movement and vision.
  • Floor of the third ventricle: This narrow cavity in the front of your brain protects it from trauma and helps transport nutrients and waste.
  • Spinal cord: Your spinal cord carries nerve signals from your brain to your body and vice versa. Nerve signals help you feel sensation and move your body.

What’s the difference between a pineal cyst and a pineocytoma?

A pineal cyst is a sac or pouch filled with fluid or air. A pineocytoma is a tumor, or mass of abnormal cells. Pineal cysts rarely grow while pineocytomas do grow, although very slowly. Pineal cysts and pineocytomas are both benign (not cancerous).

Symptoms and Causes

What are gangliocytoma and pineocytoma symptoms?

You can have a gangliocytoma without noticing any symptoms. Many times healthcare providers diagnose gangliocytomas during imaging tests to diagnose another problem. That said, gangliocytoma and pineocytoma are linked to several conditions that have a variety of symptoms. Here is more information on common conditions and symptoms.

Hydrocephalus. Both gangliocytomas and pineocytomas may cause hydrocephalus. Hydrocephalus is fluid build-up in your brain.

Balance problems.

Eye movement issues (Parinaud syndrome).


Memory issues.

Nausea and vomiting.

Sleep disruption.

Walking problems.

Increased brain pressure from gangliocytoma.


Nausea and vomiting.


Endocrine system disorders. These may be linked to pineocytoma.Feeling unusually sleepy.
Lhermitte-Duclos disease (LDD). LDD is a very rare benign tumor in your cerebellum. It may be called dysplastic gangliocytoma of the cerebellum.Symptoms related to hydrocephalus.
Ataxia. Ataxia is a group of neurological diseases affecting movement and coordination. People with LDD often have ataxia.Trouble walking, impaired balance, coordination problems.
Cowden syndrome. This is a genetic disorder linked to LDD.

Skin growths.

Increased risk for developing certain cancers.

Other gangliocytoma symptoms may include:

  • Movement changes, including loss of muscle control (tremors, paralysis and weakness).
  • Sensation changes, including numbness.
  • Speech difficulties.
  • Vision changes.
  • Seizures.

What causes these tumors?

Like most tumors, gangliocytomas and pineocytomas happen when something triggers changes in cells’ genetic instructions. Working with new instructions, cells start to multiply, eventually becoming a mass or tumor. Researchers don’t know what triggers the changes. They do know that Cowden syndrome, which is linked to Lhermitte-Duclos disease, happens when a gene called PTEN mutates. PTEN makes a protein that helps control how cells grow and divide. When the PTEN gene mutates, it stops making the protein, enabling cells to grow uncontrollably.

Diagnosis and Tests

How do healthcare providers diagnose these tumors?

To help diagnose gangliocytoma and pineocytoma, your healthcare provider will ask about your symptoms and family health history. They will do a physical exam, including a neurologic exam to look at your:

  • Eye and mouth movement.
  • Muscle strength.
  • Reflexes.

Your provider may also do the following tests:

  • Magnetic resonance imaging (MRI): This painless test that uses a large magnet, radio waves and a computer to produce very clear images of organs and structures within your body. Providers may do this test to look for tumors or evaluate tumor size and location.
  • CT (computed tomography) scan: CT scans use a series of X-rays and a computer to create three-dimensional images of your soft tissues and bones. As with MRIs, providers may use this test to look for and evaluate tumors.
  • Blood test: Your provider may test your blood for unusual melatonin levels.
  • Spinal tap (lumbar puncture): This test involves obtaining a sample of your cerebrospinal fluid, which surrounds your brain and spine. Providers do this test to examine tumor cells.
  • Biopsy: Your provider removes tumor cells for testing to determine the type of tumor. They often use minimally invasive techniques such as endoscopy or stereotactic needle biopsy.

Management and Treatment

How do healthcare providers treat gangliocytoma?

If you don’t have symptoms, your provider may recommend regular check-ups so they can monitor any symptoms you may develop and/or do imaging and blood tests to see if the tumor has changed or grown.

If you do need treatment, providers do brain surgery to surgery to remove the tumor. Once removed, gangliocytomas rarely come back.

How do healthcare providers treat pineocytoma?

In some instances, they may perform brain surgery to remove all or part of the tumor. They may also use radiation therapy. During surgery, if you have hydrocephalus, they may insert a small plastic tube called a shunt. The shunt goes into your brain’s fluid cavity to help drain cerebrospinal fluid. This reduces the pressure in your head and can ease your symptoms.


Can I prevent these tumors?

No, there’s nothing you can do to prevent these tumors. They develop when cells mutate and begin to multiply uncontrollably. Researchers don’t know what causes the mutation other than if it is associated with Cowden syndrome. Cowden syndrome happens when a gene that controls cell growth mutates.

Outlook / Prognosis

What can I expect if I have one of these tumors?

If you have surgery to remove the tumor, it rarely comes back.

Living With

When should I see my healthcare provider?

Depending on your situation, your provider may schedule regular follow-up appointments to monitor your overall health. If you had surgery to remove the tumor, providers may recommend imaging tests to confirm the tumor hasn’t come back or you haven’t developed a new tumor. You should see your provider anytime your initial tumor symptoms come back or if you're concerned about new changes in your body.

A note from Cleveland Clinic

Ganglicytomas and pineocytomas are rare, slow-growing benign tumors that develop in your central nervous system and your pineal gland. While they aren’t cancerous, they can still cause medical conditions that may disrupt your life. Depending on the type of tumor you have, healthcare providers may use surgery or radiation therapy to treat these tumors. Once removed with surgery, these tumors rarely come back. If you have one of these benign tumors, ask your provider about treatment options, what you can expect after treatment and what you need know to live with these benign tumors.

Last reviewed by a Cleveland Clinic medical professional on 04/18/2022.


  • American Association of Neurological Surgeons. Brain Tumors – Classifications, Symptoms, Diagnosis and Treatments. (https://www.aans.org/en/Patients/Neurosurgical-Conditions-and-Treatments/Brain-Tumors) Accessed 4/18/2022.
  • American Brain Tumor Association. Brain Tumor Education. (https://www.abta.org/) Accessed 4/18/2022.
  • National Brain Tumor Society. Brain Tumor Types & Symptoms. (https://braintumor.org/brain-tumor-information/signs-and-symptoms/) Accessed 4/18/2022.
  • National Cancer Institute. Pineal Region Tumors Diagnosis and Treatment. (https://www.cancer.gov/rare-brain-spine-tumor/tumors/pineal-region-tumors) Accessed 4/18/2022.

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