Malignant Rhabdoid Tumor in Children

There is no clear cause of malignant rhabdoid tumor. Researchers have discovered that a gene called SMARCB1 (this gene also goes by the names INI1, SNF5, and BAF47) is mutated in nearly all rhabdoid tumors, including malignant rhabdoid tumor and atypical teratoid rhabdoid tumor (ATRT). Mutations in this gene can also sometimes occur in a patient’s normal, non-tumor cells, increasing their risk of developing additional rhabdoid tumors. 

Often the first sign that a child has a malignant rhabdoid tumor is the discovery of a lump or mass in the child's abdomen. Because malignant rhabdoid tumor occurs most frequently in infants, the child may not show any signs of pain or discomfort beyond fussiness. Some children with malignant rhabdoid tumor may have difficulty urinating or blood in the urine.

Diagnostic procedures for malignant rhabdoid tumor are used to determine the exact type of tumor your child has and whether the tumor has spread. Your child’s doctor will perform a complete medical and physical examination. In addition, your child’s physician may order some of the following diagnostic tests for malignant rhabdoid tumor:

• Biopsy or tissue sample from the tumor to provide definitive information about the type of tumor; this is usually collected by a radiologist using a minimally invasive approach but can sometimes require surgery
• Computerized tomography scan (also called a CT or CAT scan), bone scan, and magnetic resonance imaging (MRI) to determine whether the tumor has spread

If a biopsy is taken, the sample will be tested for mutations in a gene called SMARCB1 (this gene also goes by the names INI1, SNF5, and BAF47), which is turned off in nearly all rhabdoid tumors.

If a mutation is found, your child's doctor may recommend additional tests to see if the mutation is what is called a germline mutation—the kind that is present throughout the body and could potentially be passed within families. Should those results be positive, your child's doctor may then recommend testing you and other members of your family for the mutation, along with genetic counseling.

The treatment of malignant rhabdoid tumor involves a combination of therapies including surgery, radiation, and chemotherapy. However, because this tumor is rare and aggressive, there is no defined standard of care, and treatment options may be tailored to your child's situation. Your child's doctor and other members of your care team will discuss the options with you in depth. Prompt medical attention and aggressive therapy are important for the best prognosis.

At Dana-Farber/Boston Children's, we treat children with malignant rhabdoid tumor through the Kidney Tumor Program within our Solid Tumor Center.

Surgery for malignant rhabdoid tumor

In most cases, the first step in treating malignant rhabdoid tumor is surgery. Often a surgeon will try to remove the whole tumor at the time of biopsy. Depending on the size and location of the tumor, the surgeon may remove only part of the kidney or the whole kidney.

Chemotherapy for malignant rhabdoid tumor 

After surgery, children with malignant rhabdoid tumor are treated with a very aggressive course of chemotherapy, a group of drugs that interfere with the cancer cell’s ability to grow or reproduce.

• Different groups of chemotherapy drugs work in varied ways to fight cancer cells and shrink tumors.
• Often, a combination of chemotherapy drugs is used.
• Certain chemotherapy drugs may be given in a specific order depending on the type of cancer it is being used to treat.

Does chemotherapy cause side effects? 

While chemotherapy can be quite effective in treating certain cancers, the drugs cannot tell the difference between normal, healthy cells and cancer cells. Because of this, your child may experience adverse side effects during treatment. Understanding these side effects can help you, your child, and your care team prepare for, and, in some cases, prevent these symptoms from occurring.

Chemotherapy is systemic treatment, meaning it is introduced to the bloodstream and travels throughout the body to kill cancer cells. Children with malignant rhabdoid tumor receive chemotherapy:

• Intramuscularly (or IM), as an injection into the muscle or fat tissue
• Intravenously (or IV), directly to the bloodstream

Radiation therapy for malignant rhabdoid tumor 

Children with malignant rhabdoid tumor who are more than six months old also may receive radiation therapy as part of their treatment.

Stem cell transplantation for malignant rhabdoid tumor 

The treatment of malignant rhabdoid tumor can be so intense as to affect the body's ability to produce normal blood and immune cells. For that reason, your child's doctor may recommend that your child undergo an autologous stem cell transplant. This involves temporarily removing some of a child’s healthy blood cells and giving her very high doses of chemotherapy and, in some cases, radiation therapy to overwhelm and destroy the malignant rhabdoid tumor. The child is then given back her own stored healthy blood cells to promote normal body and organ function once treatment is done.

Supportive care

Supportive care is treatment to prevent and treat infections, side effects of treatments, and complications. The goal is to keep your child comfortable during treatment. It also is an important part of preventing short- and long-term complications of the disease and treatment.

Your child’s prognosis (chance of recovery) and treatment options depend on a number of different factors:

• The extent of the disease
• The size and location of the tumor
• The tumor's characteristics when examined under a microscope
• The presence or absence of metastasis
• The tumor's response to therapy
• Your child age and overall health
• Your child's tolerance of specific medications, procedures, or therapies
• New developments in treatment

In general, malignant rhabdoid tumors are very aggressive and difficult to treat. Patients often initially respond well to treatment, but relapse either during or shortly after treatment remains a risk. Children with germline mutations to SMARCB1 also have a high risk of developing second tumors. Prompt medical attention and appropriate therapy are important for the best prognosis.

Survivorship comes with numerous complex issues: the long-term effects of treatment and the risk of second cancers, as well as social and psychological concerns. Children treated for malignant rhabdoid tumor should visit a survivorship clinic every year to:

• Manage disease complications
• Screen for early recurrence of cancer
• Manage late effects of treatment

A typical follow-up visit may include some or all of the following:

• A physical exam
• Laboratory testing
• Imaging scans

Since 1993, physicians, nurses, researchers, and psychologists at the David B. Perini Jr. Quality of Life Clinic at Dana-Farber Cancer Institute have helped thousands of survivors of pediatric cancers, treated at the institute and at other hospitals, to manage these long-term consequences. Learn more about our cancer survivorship programs.

Researchers at Dana-Farber/Boston Children's are global leaders in the basic and translational study of rhabdoid tumors, including malignant rhabdoid tumor and atypical teratoid/rhabdoid tumor. Their goal: to understand the biological basis of rhabdoid tumors, including the role(s) of mutations in the gene SMARCB1, and to develop more effective treatment methods for children with these tumors.

In addition, we have a phase I clinical trial open for children with refractory or relapsed malignant rhabdoid tumor, as well as access to any malignant rhabdoid tumor trials available through the Children's Oncology Group.

Learn more about clinical trials

For many children with rare or hard-to-treat conditions, clinical trials provide new options.

• Get answers to common questions about clinical trials for cancer and blood disorders.
• Contact us: For more information on our clinical trials, email us at clinicaltrials@danafarberbostonchildrens.org.