Rhabdomyosarcoma (RMS) is a rare type of cancer that forms in soft tissue — specifically skeletal muscle tissue or sometimes hollow organs such as the bladder or uterus. RMS can occur at any age, but it most often affects children.
Although RMS can arise anywhere in the body, it's more likely to start in the:
- Head and neck area
- Urinary system, such as the bladder
- Reproductive system, such as the vagina, uterus and testes
- Arms and legs
The outlook (prognosis) and treatment decisions depend on the type of rhabdomyosarcoma, where it starts, tumor size and whether the cancer has spread. Treatment is usually with a combination of surgery, chemotherapy and radiation therapy.
Major advancements in the treatment of rhabdomyosarcoma have significantly improved outcomes. After completion of treatment, people need lifelong monitoring for potential late effects of intense chemotherapy and radiation.
Signs and symptoms of rhabdomyosarcoma depend on where the cancer is located.
For example, if the cancer is in the head or neck area, signs and symptoms may include, among others:
- Bulging or swelling of the eyes
- Bleeding in the nose, throat or ears
If the cancer is in the urinary or reproductive system, signs and symptoms may include, among others:
- Trouble urinating and blood in the urine
- Difficulty with bowel movements
- A mass or bleeding in the vagina or rectum
If the cancer is in the arms or legs, signs and symptoms may include, among others:
- Swelling or a lump in the arm or leg
- Pain in the affected area, though sometimes there is no pain
It's not clear what causes rhabdomyosarcoma.
Doctors know that rhabdomyosarcoma begins when a cell develops changes in its DNA. A cell's DNA contains the instructions that tell a cell what to do. The changes tell the cell to multiply quickly and to go on living when healthy cells would normally die. The result is a mass (tumor) of abnormal cells that can invade and destroy healthy body tissue. The abnormal cells can break away and spread (metastasize) throughout the body.
Factors that may increase the risk of rhabdomyosarcoma include:
- Family history of cancer. The risk of rhabdomyosarcoma is higher in children with a blood relative, such as a parent or sibling, who has had cancer, particularly if that cancer occurred at a young age. But most children with rhabdomyosarcoma have no family history of cancer.
- Genetic syndromes that increase the risk of cancer. In rare instances, rhabdomyosarcoma has been linked to genetic syndromes that are passed from parents to children, including neurofibromatosis 1, Noonan syndrome, Li-Fraumeni syndrome, Beckwith-Wiedemann syndrome and Costello syndrome.
Complications of rhabdomyosarcoma and its treatment include:
- Cancer that spreads (metastasizes). Rhabdomyosarcoma can spread from where it started to other areas, making treatment and recovery more difficult. Rhabdomyosarcoma most often spreads to the lungs, lymph nodes and bones.
- Long-term treatment side effects. The aggressive treatments needed to control rhabdomyosarcoma can cause substantial side effects, in both the short and the long terms. Your health care team can help you manage the side effects that happen during treatment and provide you with a list of side effects to watch for in the years after treatment.