Rhabdomyosarcoma is a fast-growing cancer that can develop in soft tissues (such as muscle) almost anywhere in the body.

• Rhabdomyosarcomas can develop anywhere, but the head and neck, genital or urinary tract, and limbs are the most common.
• Symptoms depend on where rhabdomyosarcomas develop.
• Diagnosis involves an imaging test and a biopsy.
• Treatment consists of surgery, chemotherapy, and sometimes radiation.

Rhabdomyosarcomas account for 3 to 4% of cancers in children. Two thirds of these cancers are diagnosed in children younger than 7 years. The cancer is slightly more common among boys than girls and is more common among whites than blacks, mainly because it is less common among black girls.

This cancer develops from cells that would normally develop into muscle cells. The cause is unknown.

Although rhabdomyosarcoma can occur almost anywhere, it tends to occur in the following:

• Head and neck (in 35 to 40% of cases), most common among school-aged children
• Genital or urinary tract, usually in the bladder, prostate, or vagina (in 25%), typically occurring in infants and toddlers
• Limbs (in 20%), most common among adolescents

Rhabdomyosarcoma can spread (metastasize) to other parts of the body. But it is usually diagnosed before the cancer has spread.

Symptoms

In most children, the first evidence of the cancer is a firm lump or problems related to an organ affected by the cancer, such as the following:

• Eyes: Tearing, eye pain, or a bulging eye
• Nose and throat: Nasal congestion, a change in the voice, or a nasal discharge that contains mucus and pus
• Genital or urinary tract: Abdominal pain, a lump in the abdomen that can be felt, difficulty urinating, and blood in the urine
• Limbs: Firm lumps on the arms or legs

Limb cancers frequently spread, especially to the lungs, bone marrow, and lymph nodes. Usually, this spread does not cause symptoms.

Diagnosis

If a lump is detected, computed tomography (CT) or sometimes magnetic resonance imaging (MRI) is done. The diagnosis is confirmed by taking a sample from the lump and examining it under a microscope (biopsy). Sometimes the entire lump is removed.

To determine whether the cancer has spread, CT of the chest and a bone scan (radionuclide scanning of bones—see Common Imaging Tests: Radionuclide Scanning) are done, and a sample of bone marrow is removed and examined.

Treatment

Treatment consists of surgery, chemotherapy, and sometimes radiation. The entire cancer is removed if possible. All children are treated with chemotherapy (most commonly, vincristine, actinomycinSome Trade Names
See Dactinomycin
D, cyclophosphamideSome Trade Names
LYOPHILIZED CYTOXAN
, doxorubicinSome Trade Names
DOXIL
, ifosfamideSome Trade Names
IFEX
, and etoposideSome Trade Names
VEPESID
).

Radiation therapy is typically used if some cancer remains after surgery or if the cancer is considered high risk. Risk (and likelihood of a good outcome) depends on the following:

• Where the cancer is
• How much of the cancer can be removed
• Whether it has spread
• How old the child is
• What the cancer cells and tissue look like when examined under a microscope

Last full review/revision January 2009 by David N. Korones, MD