Rhabdomyosarcoma (RMS) is a rare type of soft tissue sarcoma. Sarcomas are cancers that develop from cells in the supporting or connective tissues of the body, such as muscle, fat, nerves, blood vessels, bone and cartilage. Rhabdomyosarcomas grow in the voluntary muscles of the body. These are muscles that we have control over, such as the muscles we use to move our arms or legs. Voluntary muscles are also called skeletal or striated muscles.
The most common parts of the body for rhabdomyosarcoma to develop are the:
- head and neck
- arms and legs
- central part of the body (trunk).
Very rarely, rhabdomyosarcoma can also be found in other areas, such as in the prostate gland, middle ear and bile duct system.
Rhabdomyosarcoma is more common in children and teenagers than in adults. For unknown reasons, slightly more men than women are diagnosed with rhabdomyosarcoma.
This type of rhabdomyosarcoma is usually diagnosed in middle-aged people. It often develops in the arms and legs.
This type of rhabdomyosarcoma is usually diagnosed in older children, teenagers and young adults. It often develops in the large muscles of the arms and legs. It can also develop in the chest or tummy (abdomen), pelvis, and head and neck area.
This type of rhabdomyosarcoma is most common in young children, usually under the age of 6. It often develops in the head and neck area, especially in the tissues around the eye (orbital rhabdomyosarcoma).
Another common area for embryonal rhabdomyosarcoma to develop is the genitourinary system. This includes the bladder, vagina and the area around the prostate gland and testicles.
You can read more about rhabdomyosarcoma in children at Children's Cancer and Leukaemia Group.
Rhabdomyosarcoma can start in any part of the body. The symptoms depend on the part of the body that is affected and the age of the person. Symptoms may include:
- a lump that you can see or feel – it may or may not be painful
- a blockage and discharge from the nose
- changes in swallowing or hearing
- a swollen eye, where the eye seems to be pushed forward
- pain in the tummy (abdomen)
- difficulty pooing (constipation)
- blood in your pee (urine) or difficulty peeing
- needing to pee more frequently (in men or boys)
- vaginal discharge (in women or girls).
If you notice any of these symptoms, you should contact your GP. Remember these symptoms can also be caused by conditions other than cancer.
The causes of rhabdomyosarcoma are unknown, but research is trying to find out more.
Most rhabdomyosarcomas are not caused by an inherited faulty gene that can be passed on to other family members. But rhabdomyosarcoma is slightly more common in children with the genetic disorders:
- Li-Fraumeni syndrome
- Beckwith-Wiedemann syndrome
- Costello syndrome.
Soft tissue sarcomas may occur in an area that has previously been treated with radiotherapy for another type of cancer.
The sarcoma does not usually develop until at least 5 to 10 years after the radiotherapy treatment.
Exposure to some types of chemical may be linked to the development of some sarcomas. The chemicals include:
- vinyl chloride – this is used for making plastics
- some types of weed killer (herbicide)
- dioxins – these are waste products made during the manufacture of chemicals and fertilisers.
Tests and diagnosis
If you have symptoms, you usually start by seeing your GP, who will examine you. If your GP is not sure what the problem is, or thinks your symptoms could be caused by cancer, they will refer you to a specialist doctor at the hospital.
You may also have blood tests to check your general health and the number of cells in your blood (blood count).
At the hospital, the specialist doctor will ask you about your symptoms and your general health. They will also examine you and arrange some of the following tests.
The tests you have will depend on the part of the body being investigated.
A biopsy means the doctor takes a sample of cells from the area to be checked for cancer under the microscope. We have more information about having a biopsy in our information about diagnosing soft tissue sarcoma. Your doctor or specialist nurse will give you more information.
Our cancer support specialists or your specialist doctor or nurse can give you information about any tests we do not explain here.
Waiting for test results can be a difficult time, we have more information that can help.
Tests may be done to check the exact size of the tumour and to find out if it has spread to any other part of the body. These may include:
- bone marrow tests
A small sample of bone marrow is taken from the back of the hip bone (pelvis) or occasionally the breast bone (sternum). This is looked at to see if there are any abnormal cells.
- a lumbar puncture
A lumbar puncture is when a hollow needle is inserted between the bones of the lower back. It is done to take a sample of the fluid that surrounds the brain and spinal cord.
The stage of a cancer describes its size and whether it has spread beyond its original site. Your doctors use information about the stage of rhabdomyosarcoma to put you into a risk group, ranging from low risk to very high risk. This helps your doctors plan the best treatment for you.
The staging and risk groups for rhabdomyosarcoma are complicated. Your doctor or specialist nurse will give you information and can answer any questions you may have.
How doctors decide on risk groups
To help your doctor put you into a risk group, they need to know:
- the type of rhabdomyosarcoma you have
- your age
- the size of the tumour and whether the cancer has spread to the lymph nodes or other parts of the body – this is called the TNM stage
- whether the cancer can be completely removed with surgery – this is called the post-surgical stage
- where in the body the tumour started – this is called the site.
TNM stands for Tumour, Node and Metastasis.
- T describes the size of the tumour.
- N describes whether the cancer has spread to the lymph nodes.
- M describes whether the cancer has spread to another part of the body, such as the liver or lungs (known as metastatic or secondary cancer).
Doctors put numbers after the T, N, and M that give more details about the size and spread of the cancer.
This is based on the size of the tumour and whether it can be completely removed.
During the operation, the surgeon removes a border (margin) of healthy tissue around the tumour. The margin is examined to see if it contains any cancer cells.
There is more information about the margin in the section about surgery.
There are four post-surgical groups:
- Group I – the tumour has been completely removed.
- Group II – the tumour has been removed, but there are cancer cells in the margin or the lymph nodes.
- Group III – the tumour could not be completely removed.
- Group IV – the cancer has spread to other parts of the body.
Some tumour sites are described as favourable. Treatment to these areas may be more successful. This includes:
- the area around the eye (orbit)
- the tubes that drain bile from the liver to the small bowel (bile ducts)
- some parts of the head and neck
- parts of the urinary system, but not the bladder or prostate gland.
Other tumour sites are unfavourable. Treatment to these areas may not be as successful. This includes:
- the bladder and prostate
- an arm or leg
- parts of the head or neck that are close to the membranes covering the brain (parameningeal sites), such as the middle ear, nasal passages and sinuses.
The risk groups
When your doctors have put all the staging information together, they can decide on your risk group. There are four risk groups:
- low risk
- standard risk
- high risk
- very high risk.
Your doctor or nurse will give you more information about your individual risk group and what it means for your treatment plan.
The treatment for rhabdomyosarcoma depends on a number of things, including your general health and your risk group.
The results of your tests help your doctor decide on the best treatment for you. They will then discuss this with you. You may be offered some treatments as part of a clinical trial.
Because sarcomas are rare cancers, you should be referred to a specialist unit for treatment. This may mean you need to travel further to have your treatment.
Chemotherapy for rhabdomyosarcoma
Treatment often begins with chemotherapy. Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy the cancer cells.
It can be given:
- before surgery, to shrink the tumour (neo-adjuvant chemotherapy)
- after surgery, to reduce the risk of the cancer coming back (adjuvant chemotherapy).
Usually a combination of chemotherapy drugs is used. The drugs used and the length of treatment depends on the type and risk group of the rhabdomyosarcoma.
Surgery for rhabdomyosarcoma
Surgery is used if the tumour can be removed without causing too much damage to nearby structures, or without affecting your appearance too much.
The type of surgery will depend on where in the body the rhabdomyosarcoma is. Your surgeon will discuss the operation with you and explain how it may affect you.
The aim is to remove all of the tumour, along with an area (margin) of normal tissue. After the operation, the pathologist examines the tissue from the margin.
If there are cancerous cells in the margin, you may need another operation to remove more tissue. Making sure the margins are clear reduces the risk of the cancer coming back.
We have more general information about surgery.
Radiotherapy for rhabdomyosarcoma
Radiotherapy uses high-energy rays to destroy cancer cells. It can be given:
- before an operation, to shrink the tumour and make it easier to remove
- if the tumour cannot be completely removed with surgery – this could be because of its size or position in the body
- if there is a possibility of cancer cells being left behind after surgery.
Sometimes chemotherapy is given at the same time as radiotherapy (chemoradiation).
Proton beam therapy
Proton beam therapy is a type of radiotherapy sometimes used to treat rhabdomyosarcoma. It uses proton radiation rather than x-rays.
Proton beams can be made to stop when they reach the area being treated. This is different to standard radiotherapy beams, which travel through the area and then continue through the body.
Using proton beam radiotherapy may help reduce damage to surrounding healthy tissues.
Everyone has their own way of dealing with illness and the different emotions they experience. You may find it helpful to talk things over with family and friends or your doctor or nurse.
Macmillan can offer emotional, practical and financial help and support. You can call us on 0808 808 00 00.
Sarcoma UK offers support and information to anyone affected by sarcoma.