Rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is a rare type of cancer known as a soft tissue sarcoma. It develops in your skeletal muscles. It can affect anyone regardless of age, but it’s most common in children and teens. About 350 to 400 children in the U.S. receive this diagnosis each year. 

Tumors can form in any place with soft tissue, but most start in the:

• Head and neck
• Arms and legs
• Chest or belly
• Urinary tract
• Genitals

There are different types of rhabdomyosarcomas, some of which are aggressive and difficult to treat. Others are curable. Your healthcare provider will explain what to expect if you or your child has this rare sarcoma.

Types of this condition

There are several types of RMS:

• Embryonal rhabdomyosarcoma: This is the most common type. It occurs most often in children under 10 years old. It typically develops in the head, neck or genitals. Subtypes like botryoid rhabdomyosarcoma may form in hollow organs like the bladder or vagina.
• Alveolar rhabdomyosarcoma: This type is most common in older children, teens and young adults. It typically develops in the arms, legs or torso. It often spreads fast. It’s sometimes called “fusion positive rhabdomyosarcoma.”
• Spindle cell/sclerosing rhabdomyosarcoma: This type affects people of all ages and usually starts in the head and neck or chest wall.
• Pleomorphic rhabdomyosarcoma: This type usually affects adults over 50. It can develop anywhere but mostly affects the legs. 

Symptoms of rhabdomyosarcoma

Symptoms vary depending on the tumor’s location. For example, a tumor in your child’s ear may cause an earache. A tumor behind their eye may make it swell or bulge. Other symptoms, by tumor location, include:

• Arm or leg muscle: Mass, lump or swelling that may hurt
• Belly (abdomen): Belly pain, constipation or vomiting
• Bladder and urinary tract: Blood in urine or trouble peeing
• Nasal cavity: Nosebleed or sinus infection symptoms
• Genitals: Mass or lump growing in the vagina or testicles

Many conditions can cause symptoms like these, and most aren’t as serious as cancer. It’s important not to jump to conclusions and worry. Still, you should contact a healthcare provider if you or your child has symptoms that don’t go away or seem to be getting worse.

Rhabdomyosarcoma causes

RMS happens when immature muscle cells change (mutate) into cancer cells. Certain genetic mutations cause this to occur. One of the most well-known with this cancer type is the fusion gene PAX/FOX01 in alveolar rhabdomyosarcoma. When PAX and FOX01 come together (fuse), they create a new cancer-specific gene.

Experts don’t know what causes the change. It’s not inherited or related to known cancer-causing substances in the environment.

Risk factors

Most people diagnosed are children under 10. Nearly 2 out of 3 are younger than 6 years old. It’s slightly more common in males.

People with certain inherited disorders have an increased risk of rhabdomyosarcoma. These conditions include:

• Li Fraumeni syndrome
• Beckwith Wiedemann syndrome
• Neurofibromatosis
• Costello syndrome
• DICER1 syndrome
• Cardiofaciocutaneous syndrome
• Noonan syndrome

How doctors diagnose this condition

A healthcare provider will ask about symptoms and family medical history. They’ll check for lumps or growths. Providers may use the following tests to diagnose RMS:

• Blood tests
• Imaging tests, like a CT scan, MRI, bone scan or PET scan
• Tests to check for cancer cells, like a lumbar puncture, bone marrow aspiration or bone marrow biopsy

Risk group classifications

Cancer doctors (oncologists) who care for children with rhabdomyosarcoma classify the condition by risk group. This helps your child’s provider plan treatment and establish a prognosis. A prognosis is your child’s outlook, or what results to expect after treatment. The risk may be:

• Low: The prognosis is excellent or very good.
• Intermediate: The prognosis is good. Most diagnoses fall into this group.
• High: The cancer will likely come back after treatment and become fatal.

Oncologists consider lots of factors to determine the risk group, including:

• The size and location of the tumor
• Whether the cancer has spread (metastases), the extent of the spread and the location of metastases
• How much of the tumor was removed during surgery
• The types of gene changes, like the presence of the PAX/FOX01 gene

How is rhabdomyosarcoma treated?

Treatment depends on the risk group. Oncologists call this risk-adapted therapy. The most common treatments are:

• Surgery: Surgeons try to remove as much of the tumor as they can. Success depends on the tumor’s location.
• Radiation therapy: Your child may need radiation therapy before surgery to shrink a tumor or afterward to destroy any microscopic cancer cells that may remain. Sometimes, radiation is the main treatment when surgery isn’t an option. Radiation can be very precise.
• Chemotherapy: This treatment uses drugs to destroy cancer cells throughout your child’s body. Chemotherapy can shrink tumors before surgery and destroy microscopic disease that surgery may have missed.

A clinical trial may also be an option. These studies test the safety and effectiveness of new treatments. Experts are studying new therapies for RMS, including treatments that target weaknesses in cancer cells.

​Complications of treatment

Survivors of childhood cancers often have to manage long-term side effects of treatment. Of course, the immediate goal is to get rid of the cancer for good. But depending on their cancer treatment, your child may have side effects in certain areas of their body that need treatment. These may include:

• Vision problems
• Incontinence
• Issues with teeth
• Problems with growth and development
• Heart problems

Cancer treatments may increase your child’s risk of developing a different type of cancer in the future.

Everyone’s situation is different. This is why your child’s healthcare provider is the best resource for explaining how your child’s RMS diagnosis and treatment may impact their health.

When should I contact my oncologist?

Contact your oncologist if treatment side effects are stronger than expected. Depending on the situation, they may have guidance on symptoms that could mean rhabdomyosarcoma is spreading or coming back.

In the meantime, make sure to attend all follow-up visits. Most oncologists continue to monitor people even after RMS goes into remission. Remission means that you don’t have symptoms and tests don’t detect signs of cancer. Frequent checkups can detect signs that the cancer has come back. If it does, your oncologist can start treatment ASAP.

What is the prognosis for rhabdomyosarcoma?

Sometimes, treatment can send rhabdomyosarcoma into remission or even cure it. In general, children are more likely to be cured than adults.

Prognosis depends on lots of factors that your cancer care team will discuss with you. These include:

• Age
• Type of rhabdomyosarcoma
• Type of gene changes
• Risk group classification
• Whether the cancer has come back after remission

Children 1 to 9 years old tend to have a better outlook than babies, older children or adults.

​How long do people with rhabdomyosarcoma live?

There’s no data on how long someone with rhabdomyosarcoma can expect to live. Researchers do track how many people are alive five years after receiving a diagnosis. When RMS comes back, it usually does so within five years. Remaining cancer-free at the five-year milestone increases the likelihood of being rid of RMS for good.

Here are the five-year survival rates for rhabdomyosarcoma in children, based on risk:

• Low risk: 80% to 95% (Around 9 out of 10 children are still alive.)
• Intermediate risk: 50% to 70%
• High risk: 20% to 30%

It’s important to remember that survival rates are estimates based on the experiences of other people. Each case is unique. Your oncology team is your best source of information on what to expect.

Is there anything I can do to feel better?

If you or your child has RMS, it’s normal to feel overwhelmed and under stress. Here are some suggestions that may help:

• Consider palliative care. This treatment focuses on improving quality of life, from easing symptoms to finding mental health support.
• Talk to a child life specialist. Child life specialists are specially trained healthcare providers who help children cope with medical experiences.
• Get some rest. If you’re receiving treatment, try to rest whenever you need to. If you’re caring for a child with RMS, talk to your healthcare provider about programs and services that provide respite care.
• Consider cancer survivorship. If you’re worried cancer will come back, ask your provider about cancer survivorship support.