Atypical Teratoid/Rhabdoid Tumor (ATRT): Symptoms, Causes, Diagnosis & Treatment — Complete Guide

Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026

Quick Answer

Atypical teratoid/rhabdoid tumor (ATRT) is a very rare, fast-growing cancer of the brain or spinal cord, classified as a grade 4 tumor. It mainly affects very young children, usually under age 3. Because symptoms such as morning headaches, vomiting and balance trouble can mimic common childhood illnesses, contact a care team promptly. Treatment usually combines surgery, chemotherapy and sometimes radiation.

What the research says

• A dedicated high-intensity regimen sharply improved survival compared with older treatments. In the Children's Oncology Group trial ACNS0333, 65 evaluable patients from birth to 22 years of age (54 of them younger than 36 months) received surgery, multiagent chemotherapy, high-dose chemotherapy with stem cell rescue, and involved-field radiation. Events such as relapse were significantly reduced versus a historical cohort in children under 36 months (hazard rate 0.43, 95% CI 0.28–0.66); four-year event-free survival for the whole group was 37% (95% CI 25–49%) and overall survival 43% (95% CI 31–55%). 91% of relapses happened within 2 years of enrollment, and 4 patients died of treatment-related causes. (Reddy et al., J Clin Oncol, 2020) [3]

• ATRT is now defined by its gene changes, and lab testing separates it into three molecular subgroups. A 2025 review explains that ATRT covers central nervous system tumors with SMARCB1 (INI-1) or SMARCA4 (BRG-1) alterations, and that combining immunohistochemistry with DNA methylation profiling and sequencing identifies three subgroups — TYR, SHH, and MYC. It cautions that diagnosis can be difficult in adolescents and adults, so a combined histologic, immunophenotypic, and molecular approach is essential. (Smith et al., Cancers, 2025) [4]

• Almost all ATRTs trace back to loss of one gene, and up to a third are linked to an inherited predisposition. A review of the field reported that inactivation of SMARCB1 is the near-universal key genetic event in ATRT, with SMARCA4 rarely affected. Up to a third of patients have rhabdoid tumor predisposition syndrome (germline SMARCB1 or SMARCA4 changes), which raises the risk of rhabdoid tumors outside the brain. Intensive multimodal treatment has improved survival, though with significant toxicity. (Huang & Margol, Adv Cancer Res, 2025) [9]

• High-dose chemotherapy with stem cell rescue and radiotherapy at first line were linked to better survival. A pooled analysis of 332 children and adolescents with newly diagnosed ATRT from 12 studies (median age 37 months) found that high-dose chemotherapy with stem cell rescue (hazard ratio for death 0.388; 95% CI 0.214 to 0.704) and first-line radiotherapy (hazard ratio 0.393; 95% CI 0.216 to 0.712) were each associated with improved overall survival. Intrathecal chemotherapy and complete surgical removal were not significantly associated with survival in the multivariate analysis. (Schrey et al., J Neurooncol, 2015) [10]

• Outcomes remain limited when the tumor has already spread. In a meta-analysis of 96 patients with disseminated ATRT from 25 studies, overall survival was 63.8% at 2 years and 45.7% at 4 years. A good response to chemotherapy before radiation and complete surgical removal were linked to better survival. (Aridgides et al., Pediatr Blood Cancer, 2023) [11]

At a Glance: ATRT Summary

What Is Atypical Teratoid/Rhabdoid Tumor (ATRT)?

Atypical teratoid/rhabdoid tumor (ATRT) is a very rare, fast-growing cancer that starts in the brain or spinal cord. Cancerous tumors are also called malignant tumors.

The World Health Organization (WHO) classifies ATRT as a grade 4 tumor, meaning it is aggressive and tends to grow and spread quickly.

ATRT happens mainly in very young children, usually under age 3. It also can occur in older children and teenagers and, very rarely, in adults. It can form in different parts of the central nervous system. Common areas include:

• The cerebellum, which helps with balance

• The brain stem, which controls breathing and heart rate

• The spinal cord

Around half of all ATRT cases start in the cerebellum or brainstem [5] [6] [8].

Treatment usually includes surgery to take out as much of the tumor as is safely possible, followed by medicine called chemotherapy. Depending on age and whether the tumor has spread, radiation therapy may be added.

Outcomes vary by age, stage, and treatment plan. Survival tends to be better for children age 3 or older when the tumor has not spread and aggressive therapy is possible, and lower for babies and when there is spread at diagnosis.

ATRT has a generally poor outcome because it spreads quickly and can be hard to remove, but a cure is possible if surgeons can completely remove the tumor [5]. The outlook also depends on genetic inheritance and how much of the tumor can safely be removed during surgery [5] [8]. In the United States, one study estimated that 470 people are living with ATRT [5] [7]. About 73 people receive this diagnosis each year, and only about 4 of them are adults [5].

The Three Molecular Types of ATRT

Researchers have found that ATRT is not a single disease. There are three main molecular types based on gene activity — and this helps researchers study which treatments work best for each type:

In the future, this information may help guide care and improve survival.

What are the symptoms of atypical teratoid/rhabdoid tumor (ATRT)?

Symptoms of ATRT depend on the tumor's size and where it forms in the brain or spinal cord. Because ATRT grows quickly, symptoms often appear suddenly and worsen over days or weeks.

Common signs include:

• Headaches that are often worse in the morning

• Nausea or vomiting

• Trouble with balance, walking, or coordination

• Changes in behavior or activity level

• Unusual sleepiness or irritability

• Seizures

• Weakness or loss of movement in part of the body

Morning headaches often ease after vomiting [6].

When ATRT affects the spinal cord, it can cause back pain, weakness in the legs, or changes in bladder or bowel function.

Symptoms in Babies

In babies, symptoms can be harder to see. Because babies cannot describe pain or headaches, physical signs are important clues. Parents may notice:

• Rapid head growth

• A bulging soft spot on top of the head

• Becoming unusually sleepy or fussy

• Not having much appetite

• Vomiting or poor head control

• Sudden eye or limb movements

Symptoms in Older Infants and Children

In older infants and young children, ATRT often causes changes in mood or coordination. A child may become clumsier, lose balance, or have new trouble walking or using one side of the body. Headaches, nausea, and vomiting are also common.

Some children develop vision changes, facial weakness, or crossed eyes if the tumor presses on the nerves that control eye or face muscles. Others may develop seizures or loss of appetite.

Can ATRT Be Detected Early?

ATRT is difficult to detect early because it grows fast and symptoms often resemble common childhood illnesses. There is no routine screening test for ATRT. Most tumors are found after children show signs and have imaging such as MRI.

Families with a known SMARCB1 or SMARCA4 gene change may have regular checkups or imaging as part of genetic counseling or surveillance plans.

When should you seek care for ATRT symptoms?

Because ATRT grows quickly, contact your child's care team as soon as symptoms appear or change. Seek medical attention right away if a child has:

• Persistent headaches, vomiting, or trouble with balance, walking, or coordination

• A head that grows faster than expected or a soft spot that bulges

• New seizures, sleepiness that is not typical, or weakness on one side of the body

These symptoms can have many causes, but sudden or worsening changes need a prompt exam. If ATRT or another serious condition is suspected, imaging such as an MRI can help find the cause and guide next steps.

What gene changes cause ATRT?

ATRT develops when certain genes that control how cells grow and divide stop working. When these control signals break down, cells in the brain or spinal cord can grow out of control and form a tumor.

The genes most often affected are SMARCB1 and SMARCA4. They help cells make a protein that keeps growth in check. When one of these genes is missing or damaged, the protein is not made correctly — then cells divide too fast and become cancerous.

SMARCB1 and SMARCA4 are tumor suppressor genes [5] [8].

Some people are born with a change in one of these genes in all their cells. This raises the chance of rhabdoid tumors and is called rhabdoid tumor predisposition syndrome.

Most of these gene changes happen by chance after birth and are not passed down from parents. But in some people, the change is inherited and present in every cell of the body — that inherited form increases the risk of ATRT and other rhabdoid tumors.

Experts do not know why these gene changes occur in most people with ATRT. The tumors are not caused by injury, diet, or environmental factors. Nothing a parent did or did not do causes the tumor to form.

Who is at risk of ATRT?

ATRT can affect anyone, but it happens most often in very young children:

• Age. Most tumors occur before age 3. ATRT is rare in older children and extremely rare in adults.

• Gender. The condition affects all genders in similar numbers. There is no known link to lifestyle, environment, or family habits.

• Inherited gene change. People born with a change in the SMARCB1 or SMARCA4 gene have an increased risk — called rhabdoid tumor predisposition syndrome.

ATRT in Adults

Adult cases are extremely rare and make up only a small fraction of all ATRT diagnoses. When ATRT appears in adults, it often develops in the upper part of the brain and causes headache, seizures, or weakness. Treatment follows the same general approach as in children: surgery, chemotherapy, and radiation.

What are the complications of ATRT?

ATRT can cause serious complications because it grows quickly and can spread through the fluid that surrounds the brain and spinal cord. This spread, called metastasis, makes treatment more complex and can lower survival rates.

Other complications include:

• Increased pressure inside the skull, leading to headaches, vomiting, or changes in alertness

• Hydrocephalus — a buildup of fluid in the brain — if the tumor blocks the typical flow of cerebrospinal fluid; this may require surgery to relieve pressure

• Recurrence — ATRT can come back even after successful treatment, often within the first few years, so regular follow-up imaging is important

• Late effects of treatment — surgery, chemotherapy, and radiation can affect thinking, growth, or hormone function, especially in very young children; these side effects may appear months or years after treatment ends

Can ATRT be prevented?

There is no known way to prevent ATRT. Most tumors happen without any warning or family history.

Because ATRT is linked to changes in the SMARCB1 or SMARCA4 genes, some families may choose genetic counseling. This can identify whether a child or relative carries a gene change that increases the chance of developing a rhabdoid tumor. If a gene change is found, regular checkups and imaging may help detect any tumors early — these steps cannot prevent ATRT, but they can allow care teams to start treatment sooner.

Remember: ATRT is not caused by injury, diet, or environmental exposures. Nothing a parent did or did not do causes this tumor to form.

How Is ATRT Diagnosed?

Diagnosis uses exams, imaging, and lab tests that look for changes in the tumor's cells and genes. Because this tumor grows quickly, getting an accurate diagnosis early is important. It usually begins with a medical history and a neurological examination that checks vision, hearing, balance, coordination, reflexes, and strength.

Because imaging results for ATRT can look like other brain tumors, professionals often use pathology — studying a small tissue sample under a microscope with special tests — to make a clear diagnosis. Once ATRT is confirmed, the care team stages the tumor and discusses treatment options.

What is the step-by-step treatment plan for ATRT?

Treatment for ATRT usually includes several steps. The plan depends on the child's age, tumor location, and whether the cancer has spread. Because ATRT grows quickly, treatment often starts soon after diagnosis.

Children with ATRT are often treated at specialty centers experienced in pediatric brain tumors. Care teams often include experts in neurosurgery, oncology, radiation therapy, rehabilitation, and genetics.

The care team may also include pediatricians or primary care physicians, neurologists and genetic counselors [5].

Step 1: Surgery

Brain tumor surgery is usually the first step. The goal is to take out as much tumor as safely possible without harming nearby brain tissue. Most children have a craniotomy for tumor removal. Complete removal may not always be possible if the tumor is near vital areas that control breathing, movement, or vision.

Step 2: MRI After Surgery — and a Shunt if Needed

After surgery, imaging (usually an MRI) shows how much of the tumor remains. If there is fluid buildup on the brain (hydrocephalus), a temporary or permanent brain shunt may be placed. A shunt is a small tube that helps move fluid from the brain to another part of the body where it can be absorbed.

Even with surgery, most children need more treatments to destroy remaining tumor cells and reduce the risk of recurrence (the cancer coming back).

Step 3: Chemotherapy

Most children receive chemotherapy after surgery. Chemotherapy uses strong medicines that travel through the bloodstream to kill cancer cells or stop them from growing — reaching cells surgery cannot take out.

Many plans use several medicines together in cycles. Common medicines include cisplatin, cyclophosphamide, etoposide, and vincristine.

Special approaches for some children include:

• High-dose chemotherapy followed by stem cell rescue, especially for infants, to delay or reduce the need for radiation

• Intrathecal chemotherapy, which delivers medicines directly into the fluid around the brain and spinal cord to target cells that have spread through that fluid

Chemotherapy can cause side effects such as tiredness, nausea, and low blood counts. Care teams monitor children closely and adjust doses to protect healthy cells.

Step 4: Radiation Therapy

Radiation uses high-energy beams to destroy tumor cells. Older children and teens may receive radiation to the tumor site or, if the cancer has spread, to the brain and spinal cord. Because radiation can affect the developing brain, care teams may delay or avoid it in babies and toddlers.

Many specialized centers use proton beam therapy, which focuses radiation more precisely on the tumor and limits exposure to nearby healthy tissue. This can reduce long-term effects on thinking, learning, and growth. Proton therapy is available only at specialized centers.

Step 5: Rehabilitation Therapy

Rehabilitation may help children recover strength, balance, and coordination after surgery or radiation. Physical, occupational, and speech therapy support recovery and improve daily functioning.

Step 6: Supportive Therapies

Children often receive supportive therapies during and after treatment. These may include nutritional support, hearing checks, hormone testing, and cognitive evaluations to monitor for late effects. Emotional and social support also are key parts of care.

Treatment can also include palliative care for comfort [5].

Potential Future Treatments

Researchers are studying new medicines that target the genes and cell pathways involved in ATRT. Other studies are testing new chemotherapy combinations, immune-based treatments, and drugs that target the genetic drivers of ATRT.

Researchers also are testing immunotherapy — such as checkpoint inhibitors and CAR-T cell therapy — and virus-based treatments in clinical trials. These approaches are experimental and available only through studies.

Can alternative medicine treat ATRT?

There are no alternative medicines proved to treat or cure ATRT. Families who want to try natural or home remedies should talk with their care teams before starting, because some products and supplements can interfere with cancer medicines or cause side effects.

Complementary and integrative therapies may help children and families cope — and work best when used with, not instead of, medical care. They can reduce stress, improve mood, and support overall well-being. Examples include:

• Music or art therapy to help children express feelings or lessen anxiety

• Relaxation or breathing exercises to improve sleep and ease tension

• Massage or gentle movement therapy for comfort, if approved by the care team

• Nutritional support — working with a dietitian to plan meals or use special drinks or feeding formulas when eating is difficult

Families should always tell the care team about any vitamins, herbs, or supplements they plan to use.

How can families support a child with ATRT at home?

ATRT has no home treatments, but families can support recovery at home through healthy routines, emotional support and regular follow-up care.

1. Healthy routines. Offer small, nutritious meals and snacks to keep up energy. Encourage rest and gentle activity as advised by the care team, take medicines as directed, and follow all care instructions at home.

2. Emotional support. Children may feel scared or frustrated during treatment — reading, art, and music can provide comfort. Parents and caregivers also may benefit from counseling or support groups.

3. Follow-up care. Regular appointments, imaging, and lab tests are important even after treatment ends. Contact the care team with any new symptoms, side effects, or emotional concerns.

Many hospitals offer survivorship programs, rehabilitation, or counseling to help families adjust after treatment and support long-term recovery.

How can families cope with ATRT and find support?

An ATRT diagnosis affects the whole family, so families benefit from staying connected with the care team and seeking emotional and practical support. Treatment can be stressful, and it's common to feel anxious, sad, or overwhelmed. Support from the care team and from others who understand can make a difference:

• Stay connected with your care team. Ask all of your questions, and write down new questions between visits. Understanding the plan helps families feel more in control.

• Seek emotional and practical support. Many cancer centers have child life specialists, social workers, and counselors for emotional needs, daily stress, or financial concerns. Support groups — online and in person — connect families with others facing similar experiences.

• Take care of yourself. Parents and caregivers need rest, healthy food, and breaks. Accepting help from friends, family, or community resources makes long treatment periods easier.

• Use supportive programs. Art, music, or relaxation therapy can help children cope with hospital stays and treatment routines.

Living with ATRT may feel difficult, but support, communication, and connection can help you find strength and hope throughout treatment and recovery.

How should you prepare for an ATRT appointment?

See your child's doctor if your child has any symptoms that worry you. If ATRT is suspected, ask for a referral to an experienced specialist in pediatric brain tumors. Consider taking a family member or friend along to help remember all the information provided.

What You Can Do

Before your child's appointment, make a list of:

1. Symptoms, including any that do not seem related to the reason for the appointment

2. All medicines your child is taking — including vitamins, herbs, and over-the-counter medicines and their dosages

3. Key personal information, such as major stresses or recent changes in your child's life

4. Questions for the healthcare team to make the most of your time

Questions to Ask Your Doctor

• Where is the brain tumor located? How large is it?

• How aggressive is the brain tumor?

• Is the brain tumor cancerous?

• Will my child need additional tests?

• What are the treatment options?

• What are the benefits and risks of each treatment?

• Can any treatments cure my child's brain tumor?

• Is there one treatment you feel is best for my child?

• Should my child see other specialists? What will that cost, and will my insurance cover it?

• Are there brochures or other printed material I can have? What websites do you recommend?

What to Expect From Your Doctor

Be prepared to answer questions about your child's medical history and symptoms:

• When did your child first begin experiencing symptoms?

• Do the symptoms happen all the time or do they come and go?

• How severe are the symptoms?

• What, if anything, seems to make your child's symptoms better?

• What, if anything, appears to worsen the symptoms?

Frequently Asked Questions About ATRT

What is atypical teratoid/rhabdoid tumor (ATRT)?

ATRT is a very rare, fast-growing, malignant (cancerous) brain or spinal cord tumor. The World Health Organization classifies it as a grade 4 tumor, meaning it is aggressive and tends to grow and spread quickly.

Who gets ATRT?

ATRT happens mainly in very young children, usually under age 3. It can also occur in older children and teenagers and, very rarely, in adults. The condition affects all genders in similar numbers.

What causes ATRT?

ATRT develops when the SMARCB1 (also called INI1) or SMARCA4 genes — which normally make a protein that keeps cell growth in check — stop working. Most of these gene changes happen by chance after birth, though an inherited form called rhabdoid tumor predisposition syndrome also exists. Nothing a parent did or did not do causes this tumor.

What are the symptoms of ATRT?

Symptoms often appear suddenly and worsen over days or weeks, and include morning-worse headaches, vomiting, trouble with balance and coordination, behavior changes, unusual sleepiness, seizures, and one-sided weakness. In babies, watch for rapid head growth, a bulging soft spot, unusual sleepiness or fussiness, and poor head control.

How is ATRT diagnosed?

Diagnosis typically involves a neurological examination, brain MRI (or CT), a biopsy with molecular testing to confirm the tumor type and grade, and a lumbar puncture after diagnosis to check whether the tumor has spread through the cerebrospinal fluid.

How is ATRT treated?

Treatment usually starts with surgery to remove as much of the tumor as safely possible, followed by chemotherapy (sometimes high-dose with stem cell rescue in infants). Radiation may be added for older children, often using precise proton beam therapy, with rehabilitation and supportive care throughout.

Can ATRT be prevented?

There is no known way to prevent ATRT, and most tumors happen without warning or family history. Families with a known SMARCB1 or SMARCA4 gene change may use genetic counseling and regular checkups to detect tumors early, but the tumor is not caused by injury, diet, or environmental exposures.

What is the outlook for a child with ATRT?

ATRT is a serious, fast-growing cancer, but the outlook varies. It depends on the child's age, how much of the tumor can be removed, whether it has spread and its molecular type, and your care team can explain what to expect.

Should our family have genetic testing after an ATRT diagnosis?

Genetic counseling and testing are usually recommended. Some children carry a SMARCB1 or SMARCA4 gene change from birth, and knowing this helps guide care and checkups for siblings and future pregnancies.

Is radiation safe for very young children with ATRT?

Radiation can affect the developing brain, so care teams weigh its benefits carefully in very young children. They may delay it or use highly precise methods, such as proton therapy, to protect healthy tissue.

Conclusion

ATRT is a rare and frightening diagnosis, but understanding it is the first step toward acting quickly and finding the best care. Three lessons stand out:

• Speed matters — trust sudden changes. ATRT grows fast and mimics common childhood illnesses. Morning headaches, vomiting, balance trouble, unusual sleepiness, or a baby's rapidly growing head all deserve a prompt medical exam, not a wait-and-see approach.

• It's genetic, not anyone's fault. ATRT comes from SMARCB1 or SMARCA4 gene changes that usually happen by chance after birth — nothing a parent did or didn't do causes this tumor.

• Treatment is intensive and team-based. Surgery, chemotherapy (sometimes with stem cell rescue), precise radiation, rehabilitation, and family support work together at specialty pediatric centers — and research into molecular-targeted and immune therapies keeps expanding the options.

From the three molecular types through every warning sign, diagnosis step, and treatment stage, this guide gives families a complete picture of ATRT. For more in-depth guides on related topics, explore the rinnit.com health library — including our complete guide on astrocytoma and other brain tumor types.

Disclaimer: This article is for general informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for diagnosis and treatment.

Related Reading

Childhood Brain Tumors: Types, Symptoms, and Treatment Explained explains the main types of brain tumors in children.

Hydrocephalus: Symptoms, Causes & Treatment — What You Need to Know explains fluid buildup in the brain, a common ATRT complication.

Autologous Stem Cell Transplant: Procedure, Benefits, and Recovery explains stem cell rescue used after high-dose chemotherapy.

Brain MRI: Why It's Done, How to Prepare and What to Expect explains the brain scan used to find and track brain tumors.

References

1. Mayo Clinic. Atypical teratoid rhabdoid tumor (ATRT) — Symptoms & causes. Accessed October 12, 2026. https://www.mayoclinic.org/diseases-conditions/atypical-teratoid-rhabdoid-brain-tumor/symptoms-causes/syc-20593005

2. Mayo Clinic. Atypical teratoid rhabdoid tumor (ATRT) — Diagnosis & treatment. Accessed October 12, 2026. https://www.mayoclinic.org/diseases-conditions/atypical-teratoid-rhabdoid-brain-tumor/diagnosis-treatment/drc-20593006

3. Reddy AT, Strother DR, Judkins AR, et al. Efficacy of high-dose chemotherapy and three-dimensional conformal radiation for atypical teratoid/rhabdoid tumor: a report from the Children's Oncology Group trial ACNS0333. J Clin Oncol. 2020;38(11):1175-1185. PMID 32105509. https://doi.org/10.1200/JCO.19.01776

4. Smith HL, Aouad P, Wadhwani NR. Atypical teratoid rhabdoid tumor: how tumor diagnostic methods in the laboratory have evolved over the past 40 years. Cancers (Basel). 2025;17(23):3768. PMID 41374972. https://doi.org/10.3390/cancers17233768

5. Cleveland Clinic. Atypical Teratoid/Rhabdoid Tumor (AT/RT). Cleveland Clinic. Last updated September 27, 2024. https://my.clevelandclinic.org/health/diseases/atrt-cancer

6. American Brain Tumor Association. Atypical Teratoid Rhabdoid Tumor (ATRT). American Brain Tumor Association. Content last reviewed April 2022. https://www.abta.org/tumor_types/atypical-teratoid-rhaboid-tumor-atrt/

7. National Cancer Institute. Atypical Teratoid/Rhabdoid Tumor (AT/RT): Diagnosis and Treatment. National Cancer Institute. Updated August 20, 2024. https://www.cancer.gov/rare-brain-spine-tumor/tumors/atrt

8. National Cancer Institute. Childhood Central Nervous System Atypical Teratoid/Rhabdoid Tumor Treatment (PDQ®)–Patient Version. National Cancer Institute. Updated December 19, 2024. https://www.cancer.gov/types/brain/patient/child-cns-atrt-treatment-pdq

9. Huang MA, et al. Current advances in the management of atypical teratoid rhabdoid tumors (ATRT). Adv Cancer Res. 2025;167:185-241. PMID 41198337. https://doi.org/10.1016/bs.acr.2025.08.007

10. Schrey D, et al. Multimodal therapy in children and adolescents with newly diagnosed atypical teratoid rhabdoid tumor: individual pooled data analysis and review of the literature. J Neurooncol. 2015;126(1):81-90. PMID 26608522. https://doi.org/10.1007/s11060-015-1904-0

11. Aridgides PD, et al. Focal versus craniospinal radiation for disseminated atypical teratoid/rhabdoid tumor following favorable response to systemic therapy. Pediatr Blood Cancer. 2023;70(7):e30351. PMID 37073482. https://doi.org/10.1002/pbc.30351