What is a pineal tumor?

A pineal tumor is a tumor or mass that forms in the pineal gland. This small gland is in the middle of your head. It's surrounded by your brain. It makes a hormone called melatonin that affects your sleep-wake cycles. Pineal tumors are very rare. They're found in children more often than adults.  

There are different types of pineal tumors. Sometimes a single tumor can be a mix of several different types. Pineal tumors can be slow growing or fast growing.

The World Health Organization (WHO) has a grading system for brain tumors. It uses grades I (1), II (2), III (3), and IV (4). Grade I is the slowest growing. Grade IV is the most aggressive and grows and spreads faster. The kinds of tumors that form in the pineal gland are most commonly these types and grades: 

• Pineocytoma. These are slow-growing (grade I). These tumors usually appear between ages 20 and 60. But they can happen to a person at any age. People with pineocytomas tend to have a good outcome after the tumor is removed.  

• Pineal parenchymaltumor with intermediate differentiation (PPTID). These are intermediate-grade (grade II or III). They can happen at any age, but tend to be found in middle-aged adults (20 to 70 years old). 

• Papillary pineal tumor. These are intermediate-grade (grade II or III). They may happen at any age, but are most often found in middle age. 

• Pineoblastoma. These are very aggressive and fast-growing (grade IV). They're almost always cancer. They've often spread into nearby tissues by the time they're diagnosed. These tumors are most often found in young children. 

• Mixed pineal tumor. These are a mix of slow- and fast-growing cell types. 

Pineal tumors are not always cancer. But they still cause problems as they grow because they press against the brain and can block the normal flow of cerebral spinal fluid (CSF). CSF is the fluid that surrounds and cushions the brain. Blocking CSF flow raises intracranial pressure (ICP), the pressure inside your skull.

What causes a pineal tumor?

Researchers don't know what causes pineal tumors. Your genes and your environment may play a role. In some cases, exposure to radiation or gene problems may increase the risk.

What are the symptoms of a pineal tumor?

Fast-growing tumors may cause symptoms that worsen quickly. Some of the common signs and symptoms of a pineal tumor include: 

• Headaches (common) 

• Nausea and vomiting 

• Vision changes 

• Trouble with eye movements 

• Tiredness 

• Memory problems  

• Trouble walking

• Balance or coordination problems

• Growth and development delays in infants and children

Many of the symptoms of a pineal tumor can be caused by other health problems. Still, it's important to see a healthcare provider for a diagnosis.

How is a pineal tumor diagnosed?

Your healthcare provider will talk with you about your personal and family health history and the symptoms you've been having. A physical exam that includes a neurologic exam will be done. Your provider may test your reflexes, muscle strength, and eye and mouth movement and coordination.  

If a provider thinks you may have a pineal tumor, you may need tests, such as: 

• MRI. This imaging test uses radio waves, magnets, and a computer to make detailed 3-D images of the brain and spinal cord. A contrast dye might be put into a vein in your hand or arm before this scan. It helps get even clearer images of the inside of your body.  

• Biopsy. Tumor cells are taken out and sent to a lab for testing. This is done to find out the type and grade of the tumor.  

• Spinal tap (lumbar puncture). The provider puts a thin needle between the bones of your lower spine to take out a small amount of CSF. The CSF sample is tested for tumor cells and other substances. 

• Blood tests. These can be used to measure levels of melatonin, certain proteins, and other substances in your blood.

You may first see your primary care provider. You may then be referred to a provider who specializes in brain problems. This may be a neurologist, neurosurgeon, or neuro-oncologist.

How is a pineal tumor treated?

These tumors are very rare. It may be hard to find a provider with experience in treating them. If you've been diagnosed with a pineal tumor, you may want to see another provider to get a second opinion. This may help you better understand your treatment options and feel good about the treatment choices you make.

The treatment for your pineal tumor will depend on how big it is, where it is (if it has spread), the type, and the grade of the tumor. It will also depend on your age and whether the tumor is causing problems by pressing on your brain.

Surgery is often needed to remove a pineal tumor. Sometimes radiation therapy or chemotherapy is needed after surgery. These treatments might also be used instead of surgery. You'll work with your medical team to decide on the best treatment plan for you.

You may need to have a small plastic tube (called a shunt) put into your skull. It's used to drain CSF from your head. This helps lower the pressure inside your head (intracranial pressure) and ease symptoms. 

Pineal tumors may be hard to remove with surgery because they're so deep in the center of the brain. In some cases, healthcare providers use a computer to help them focus high-powered radiation on the exact area of the tumor. This is called a stereotactic radiosurgery, but no cutting is involved.

After treatment, you'll likely need to have regular follow-up MRIs to watch for signs that the tumor has come back.

Key points about pineal tumor

• A pineal tumor is a rare tumor that starts in the pineal gland in the center of your head. The pineal gland makes melatonin, a substance that regulates your sleep-wake cycle.  

• Pineal tumors can happen at any age, but they're more common in children and young adults. 

• The cause is unknown. 

• Pineal tumors can be slow-growing or fast-growing. 

• These tumors may cause problems by pressing against other parts of the brain. 

• Pineal tumors may block the normal flow of CSF. This causes increased pressure inside the head. 

• These tumors are diagnosed with blood tests, biopsy, and imaging tests.

• You may need surgery, radiation, chemotherapy, or a combination for a pineal tumor.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

• Know the reason for your visit and what you want to happen.

• Before your visit, write down questions you want answered.

• Bring someone with you to help you ask questions and remember what your provider tells you.

• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.

• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.

• Ask if your condition can be treated in other ways.

• Know why a test or procedure is recommended and what the results could mean.

• Know what to expect if you do not take the medicine or have the test or procedure.

• If you have a follow-up appointment, write down the date, time, and purpose for that visit.

• Know how you can contact your provider if you have questions.