Overview Rhabdomyosarcoma is a type of sarcoma. Sarcoma is cancer of soft tissue (such as muscle), connective tissue (such as tendon or cartilage), and bone. Rhabdomyosarcoma usually begins in muscles that are attached to bones and that help the body move. Rhabdomyosarcoma is the most common type of sarcoma found in the soft tissues of children. It can occur in many places in the body.
Tumor Types There are three main types of rhabdomyosarcoma:
• Embryonal: This type occurs most often in the head and neck area or in the genital or urinary organs. It is the most common type. • Alveolar: This type occurs most often in the arms or legs, chest, abdomen, or genital or anal areas. It usually occurs during the teen years. • Anaplastic: This type rarely occurs in children.
Symptoms Lumps and other symptoms may be caused by childhood rhabdomyosarcoma. The symptoms that occur depend on where the cancer forms. Other conditions may cause the same symptoms. Consult a doctor if any of the following problems occur:
• A lump or swelling that keeps getting bigger or does not go away. It may be painful. • Bulging of the eye. • Headache. • Trouble urinating or having bowel movements. • Blood in the urine. • Bleeding in the nose, throat, vagina, or rectum.
Treatment Different types of treatments are available for children with rhabdomyosarcoma. Some treatments are standard (the currently used treatment, often referred to as “standard of care”), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.
Because cancer in children is rare, taking part in a clinical trial should be considered. Some clinical trials are open only to patients who have not started treatment.
Three types of standard treatment are used:
Surgery Surgery (removing the cancer in an operation) is used to treat childhood rhabdomyosarcoma. A type of surgery called wide local excision is often done. A wide local excision is the removal of tumor and some of the normal tissue around it, including the lymph nodes. When an extra amount of normal tissue is removed from around the tumor, it is called an en bloc removal of a cuff of normal tissue. A second surgery may be needed to remove all the cancer. Whether surgery is done and the type of surgery done depends on the following:
• Where in the body the tumor started. • The effect the surgery will have on the way the child will look. • The effect the surgery will have on the child's important body functions. • How the tumor responded to chemotherapy or radiation therapy that may have been given first.
For most children with rhabdomyosarcoma, complete removal of the tumor by surgery is not possible.
Rhabdomyosarcoma can form in many different places in the body and the surgery will be different for each site. Surgery to treat rhabdomyosarcoma of the eye or genital areas is usually a biopsy. Chemotherapy, and sometimes radiation therapy, may be given before surgery to shrink large tumors.
Even if the doctor removes all the cancer that can be seen at the time of the surgery, patients will be given chemotherapy, with or without radiation therapy, after surgery to kill any cancer cells that are left. Treatment given after the surgery, to lower the risk that the cancer will come back, is called adjuvant therapy.
Radiation therapy Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or stop them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. The way the radiation therapy is given depends on the type and stage of the cancer being treated. The type and amount of radiation therapy and when it is given depend on where in the body the tumor started, how much tumor remained after surgery, and the age of the child.
Types of external radiation therapy include the following:
• Conformal radiation uses a computer to create a 3-dimensional picture of the tumor. The radiation beams are shaped to fit the tumor. • Intensity-modulated radiation therapy (IMRT) uses images created by a computer that show the size and shape of the tumor. Thin beams of radiation of different intensities are aimed at the tumor from many angles. • Fractionated stereotactic radiation therapy uses a rigid head frame attached to the skull to aim radiation directly to a tumor, causing less damage to nearby healthy tissue. The total dose of radiation is divided into several small doses given over several days. This procedure is also called stereotactic external-beam radiation therapy and stereotaxic radiation therapy. It may be used for rhabdomyosarcomas of the head and neck. • Proton-beam therapy is a type of high-energy, external radiation therapy that uses streams of protons (small, positively-charged particles of matter) to kill tumor cells.
Chemotherapy Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). Combination chemotherapy is treatment using more than one anticancer drug. The way the chemotherapy is given depends on the type and stage of the cancer being treated.