Atypical teratoid rhabdoid tumor

What is an atypical teratoid rhabdoid tumor?

An atypical teratoid rhabdoid tumor, often called AT/RT, is a very rare and fast-growing tumor of the central nervous system. If your child has been diagnosed with an ependymoma, there are a number of things that you should know:

• AT/RT’s are part of a larger group of malignant tumors called rhabdoid tumors, which can occur outside of the brain in the kidneys, liver or other locations.
• In most cases, AT/RT is associated with a specific genetic mutation (INI1) that can occur spontaneously or be inherited.
• AT/RT can occur anywhere in the brain but are most commonly found in cerebellum (base of the brain) and brain stem (the part of the brain that controls basic body functions).
   

What causes atypical teratoid rhabdoid tumor?

As a parent, you undoubtedly want to know what may have caused your child’s tumor. More than 90 percent of cases of AT/RT are associated with a genetic defect. However, the cause of this abnormality is not known.

• This genetic mutation (INI1) may be inherited, in which case tumors may also occur in the kidneys and other parts of the body.
• This defect may also occur spontaneously.

It’s important to understand that these and other brain tumors most often occur with no known cause. There’s nothing that you could have done or avoided doing that would have prevented the tumor from developing.
 

What are the symptoms of atypical teratoid rhabdoid tumor?

AT/RT grows very rapidly and, as a result, symptoms can develop quickly over days or weeks. Common symptoms of AT/RT include:

• headache (especially upon waking in the morning)
• nausea and vomiting
• fatigue and lethargy
• trouble with balance and coordination
• increased head size in infants (hydrocephalus)
   

Your child’s symptoms may vary based on his age and the location of the tumor.

The symptoms of a brain tumor may resemble other, more common conditions or medical problems. Always consult your child's physician for a diagnosis.
 

How are atypical teratoid rhabdoid tumors classified?

For many tumors, we use a system of classification called “staging,” that physicians use to evaluate cancers. However, there is currently no standardized classification system for AT/RT. The tumor may be:

• localized, occurring in only one location in the brain
• disseminated, spread to multiple locations in the brain, central nervous system or body
   

In addition, these tumors are classified as:

• newly diagnosed
• recurrent (returning after initial treatment)
   

Using a variety of diagnostic tests, your child’s physician will gather as much information as possible about your child’s tumor and will discuss treatment options with you and your family.