• Atypical Teratoid Rhabdoid Tumor (ATRT)

    What is an Atypical Teratoid Rhabdoid Tumor (ATRT)?

    Atypical teratoid rhabdoid tumors (ATRT) are very rare, aggressive tumors of the central nervous system, occurring mostly in the cerebellum (the part of the brain that controls movement and balance) or the brain stem (the part of the brain that controls basic body functions).

    • ATRTs usually occur by age 3, but occasionally arise in older children.
    • ATRTs represent only 1 to 2 percent of childhood brain tumors.
    • These tumors are part of a larger group of malignant tumors called rhabdoid tumors, which can occur outside the brain (such as rhabdoid tumor of the kidney).
    • ATRTs may be localized to one part of the brain. They can also spread to other locations in the brain, spine or body.

    ATRT Treatment at Dana-Farber/Boston Children's

    Children with ATRT are treated at Dana-Farber/Boston Children's through our Brain Tumor Center, a world leader in treating this rare disease. Our brain tumor specialists have extensive expertise in treating all types of neural tumors, including ATRT. At Dana-Farber/Boston Children’s, your child will:

    • receive care from neuro-oncologists, neurosurgeons, neurologists, and pediatric subspecialists.
    • have access to technological advances such as the intra-operative MRI, which allows pediatric neurosurgeons to see the tumor as they operate and remove as much of it as possible.
    • receive expert diagnosis by neuropathologists who use advanced molecular diagnostic testing.

    How is ATRT classified?

    Successfully treating your child’s ATRT depends on where the tumor is located and whether the tumor has spread.

    For many tumors, we use a system of classification called “staging” to evaluate cancers. However, there is currently no standardized classification system for atypical teratoid rhabdoid tumors. An ATRT may be:

    • localized, occurring in only one location in the brain
    • disseminated, spread to multiple locations in the brain, spinal cord or body

    What are ATRT symptoms and causes?

    Atypical teratoid rhabdoid tumors can cause a variety of symptoms in children depending on their size and location. Keep in mind that the symptoms may resemble other more common conditions or medical problems. It is important to consult your child's physician if you have concerns.

    ATRT symptoms can come on quickly, in a matter of days or weeks, due to the fast-growing nature of these tumors. ATRT symptoms include:

    • Headache, generally upon awakening in the morning
    • Hydrocephalus, where there is a buildup of fluid in the brain which can result increased head size in infants or headaches and vomiting in older children.
    • Nausea and vomiting. These symptoms are often worse in the morning and improve throughout the day
    • Lethargy and fatigue
    • Trouble with balance and coordination

    As a parent, you undoubtedly want to know what may have caused your child’s tumor. It’s important to remember that nothing you could have done or avoided doing would have prevented the tumor from developing.

    In most cases, atypical teratoid rhabdoid tumors are associated with a specific mutation (INI1) that can occur spontaneously or be inherited. More than 90 percent of cases of ATRT are associated with this mutation and are not inherited. However, the cause of this abnormality is not known.

    If this mutation (INI1) has been inherited, your child may be at increased risk of developing other tumors.

    How is ATRT diagnosed?

    The first step in treating your child's ATRT is forming an accurate and complete diagnosis. ATRT is most commonly diagnosed from imaging studies and biopsy. Your child's doctor will likely conduct tests including:

    • A physical exam and complete medical history. A neurological function test of reflexes, muscle strength, eye and facial movement, coordination and alertness.
    • Magnetic resonance imaging (MRI), a diagnostic procedure that produces detailed images of the structures within the brain and spine. An MRI uses a combination of large magnets, radiofrequencies and a computer to analyze organs and structures within the body. No x-rays or radiation are used.
    • Computerized tomography scan (also called a CT or CAT scan), a diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images, often called slices, of the body from horizontal and vertical perspectives. CT scans are more detailed than general x-rays.
    • Biopsy, a tissue sample from the tumor during a surgical procedure.
    • Lumbar puncture, (spinal tap) to remove a small sample of cerebrospinal fluid (CSF). This can determine if any tumor cells have spread. This procedure can safely be performed under sedation.
    • Ultrasound, a diagnostic imaging procedure that does not use x-rays, but sound waves to evaluate organs in the body. It is good at looking at organs in the abdomen such as the kidney. This test can usually be done without any sedation.
    • Genetic testing, to look for a specific genetic defect often associated with ATRT and to insure that you are not at increased risk of developing other tumors.

    There may be other diagnostic tests that your doctor will discuss with you depending on your child's individual situation. After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. Then we will be able to discuss the results and outline the best possible treatment options.

    What are ATRT treatments?

    Your child's physician will determine a specific course of ATRT treatment based on several factors, including your child's age, overall health and medical history, the type, location, and size of the tumor and the extent of the disease.

    ATRT treatments include:

    • Neurosurgery: Surgery is usually performed first in order to remove as much of the tumor as possible.
    • Radiation: High-energy waves from a specialized machine damage or shrink tumors. Precisely targeted and dosed radiation therapy is used to kill cancer cells left behind after surgery. Because ATRT occurs in children under 3, reduced intensity, limited field radiation therapy is used or radiation is avoided altogether; children over 3 generally receive radiation therapy as standard treatment.
    • Chemotherapy:Chemotherapy are drugs that interfere with the cancer cells' ability to grow or reproduce. Chemotherapy can be given in several different ways, but intrathecal chemotherapy is an important part of treatment as it allows medicine to be delivered directly to the spinal fluid and the central nervous system to treat the tumor.
    • Stem cell transplant: This allows children with aggressive ATRT to receive high doses of chemotherapy. This treatment aims to transfuse healthy bone marrow cells into your child after his marrow has been damaged by the intensive chemotherapy.
    There is no standard treatment for recurrent ATRT. Children with recurrent disease are often referred to clinical trials for the latest experimental therapies.

    What is the latest ATRT research?

    Because ATRT is so rare, these tumors are difficult to study. As a result, our researchers collaborate with other institutions around the country to improve our current understanding of this condition and offer new treatments to children with ATRT. Currently, researchers at Dana Farber/Boston Children’s are working with the Children’s Hospital of Philadelphia and the Broad Institute of MIT and Harvard to learn more about the molecular characteristics of atypical teratoid rhabdoid tumors.

    In addition, researchers in our Brain Tumor Center are collaborating with physicians and researchers that treat other types of rhabdoid tumors in order to study the effectiveness of current treatments and to establish new, more standardized treatments for all types of rhabdoid tumors.

    Through clinical trials, our researchers are testing new, targeted treatments that may help improve the survival rate for ATRT.

    Most children with a diagnosis of ATRT will be treated as part of a brain tumor clinical trial. In addition to launching our own clinical trials, we also offer trials available through collaborative groups such as the Children's Oncology Group (COG) and the Pacific Neuro-oncology group (PNOC). We are also the New England Phase I Center of the Children's Oncology Group. If your child has progressive or recurrent tumor, she may be eligible for a number of experimental therapies available through these groups, or from one of our independent clinical investigators.

    Clinical Trials

    Participation in any clinical trial is completely voluntary. We will take care to fully explain all elements of the treatment plan prior to the start of the trial, and you may remove your child from the medical study at any time.

    What is the long-term outlook for children with ATRT?

    ATRT is a very difficult tumor to cure and, unfortunately, the outcomes remain poor. In general, older children with ATRT tend to do better than young children. Through the studies done at Dana-Farber we have been able to improve the cure rates from 10 percent to 50%.

    After ATRT treatment is completed we will continue to follow your child to monitor for disease recurrence. After 2 years from completion of therapy we also recommend that children treated for an ATRT should visit a survivorship clinic yearly to manage disease complications, screen for recurrence and manage late treatment side effects. A typical follow-up visit is likely to include a physical exam, laboratory testing and imaging scans.

    Through our Stop & Shop Family Pediatric Neuro-Oncology Outcomes Clinic, children are able to meet with their neurosurgeon, radiation oncologist, pediatric neuro-oncologist and neurologists at the same follow-up visit. Our multidisciplinary approach and depth of expertise will give your child on-site access to endocrinologists, neuro-psychologists and alternative/complementary therapy specialists. School liaison and psychosocial personnel from the pediatric brain tumor team are also available. In addition, children needing rehabilitation may meet with speech, physical, and occupational therapists during and after their visit.