Ewing sarcoma is a rare type of cancer. It can affect a person of any age, but it's most common between ages 10 and 20. It often grows in bone, but it can also grow in soft tissue that's connected to the bone. This may include tendons, ligaments, cartilage, or muscles.

Ewing sarcoma most often grows in:

• Bones of the legs, arms, hips (pelvis), chest (such as the ribs or shoulder blades), spine, or skull
• Soft tissue of the torso, arms, legs, neck, or head

The exact cause of Ewing sarcoma isn't known. The cancer is caused by changes in the DNA of the cells. These genetic changes aren't passed on from parents to children. They happen by chance.

Symptoms can vary in each child. They can include:

• Pain in the bone or around the site of the tumor that may come and go but gets worse over time and with activity
• Swelling, stiffness, or tenderness in the bone or around the site of the tumor
• A lump (mass)
• A bone breaks for no known reason
• Fever
• Weight loss
• Feeling tired

The symptoms of Ewing sarcoma can be like other, more common health conditions. Make sure your child sees a doctor for a diagnosis.

Your child's doctor will ask about your child's health history and symptoms. They will examine your child. Your child may be referred to a specialist. This may be a bone specialist (orthopedic surgeon) or a bone cancer specialist (orthopedic oncologist). Your child may have tests, such as:

• X-ray. An X-ray uses a small amount of radiation to take pictures of bones and other body tissues.
• Blood tests. The blood may be tested to look for signs of Ewing sarcoma. They also help get an idea of your child's overall health.
• CT (computed tomography) scan. This test uses a series of X-rays taken from different angles and a computer to make detailed images of the inside of the body.
• MRI (magnetic resonance imaging). Large powerful magnets, radio waves, and a computer are used to make detailed images of the inside of the body.
• Bone scan. A small amount of radioactive tracer is put into your child's blood through a vein. The whole body is then scanned. The radioactive tracer shows up in areas of bone where there may be cancer.
• Positron emission tomography (PET) scan. For this test, a small amount of radioactive sugar is put into the blood. Cancer cells use more of the sugar than normal cells, so it collects in cancer cells. A special camera is used to see where the radioactive sugar is in the body. A PET scan can sometimes find cancer cells in other parts of the body, even when they can't be seen by other tests. This test is often combined with a CT scan. This is called a PET/CT scan.
• Bone marrow aspiration or biopsy. Bone marrow is the spongy center of some bones. It's where blood cells are made. A small amount of bone marrow may be taken out with a needle. This is called aspiration. Or a solid core bone marrow tissue may be taken. This is called a core biopsy. Bone marrow is most often taken from the hip bone. This test may be done to see if cancer cells have spread into the bone marrow. Talk with your child's doctor about the type of anesthesia that will be used to reduce or block the pain of the procedure.
• Tumor biopsy. A biopsy is done by taking out a small piece (sample) of the tumor. It might be done with a needle or by a surgical cut (incision). The sample is sent to a lab and tested for cancer cells. A biopsy is needed to diagnose Ewing sarcomas. Special tests may be done on the biopsy sample to check for genetic changes and biomarkers.

After a diagnosis of Ewing sarcoma, your child may need other tests. These help the doctors learn more about the cancer. They can show how much and how far the cancer has spread (metastasized) in your child's body. A stage grouping is then assigned.

More commonly, doctors classify Ewing tumor as localized or metastatic.

• Localized tumors are in only the bone where they started and maybe in nearby tissues like muscles or tendons.
• Metastatic Ewing sarcoma has clearly spread when looking at imaging scans. Most of the time, it spreads to other bones, the lungs, or the bone marrow. Less often, it can spread to the liver or lymph nodes.

Bone cancers are staged according to the American Joint Committee on Cancer staging system, which includes four key pieces of information:

• T describes the size of the tumor and whether it appears in different areas of the bone.
• N describes the extent of spread to nearby lymph nodes.
• M indicates whether the cancer has metastasized (spread) to other organs of the body.
• G stands for the grade of the tumor, which describes how the cells from biopsy samples look.

Once the T, N, M, and G information is obtained, Ewing sarcoma is assigned an overall stage. Stage groupings can have a value of 1 to 4. They are written as Roman numerals I, II, III, and IV. The higher the number, the more cancer there is and the more it has spread from where it first started. Letters and numbers can be used after the Roman numeral to give more details.

The stage of a cancer is one of the most important things to know when deciding how to treat it. Be sure to ask your child's doctor to explain the stage of your child's cancer in a way you can understand.

Treatment depends on the stage and other factors. Ewing sarcoma can be treated with any of these. Many times, more than one treatment is used:

• Surgery. Surgery may be done to remove the tumor and some normal tissue that's around the tumor (margin). Surgery methods used are often able to save an arm or leg so that it doesn't need to be amputated. This is called limb-salvage or limb-sparing surgery.
• Chemotherapy (chemo). This treatment uses strong medicines that kill cancer cells. Chemo is often given before surgery to shrink the tumor. It may also be given after surgery. Chemo is given in cycles with periods of rest. Often, more than one chemo medicine is given in combination.
• Radiation therapy. These are high-energy X-rays or other types of radiation. Radiation is used to kill cancer cells or stop them from growing. It may be used when it's hard to take out all of the tumor with surgery.
• High-dose chemotherapy with a stem cell transplant. Young blood cells (stem cells) are taken from the child or from someone else. Then high doses of chemotherapy are given. This damages the bone marrow. After the chemo, the stem cells are replaced. This treatment may be used when there's a high risk of cancer coming back.
• Clinical trials. Ask your child's doctor if there are any treatments being tested that may work well for your child. Most children with cancer are treated as part of a clinical trial. This allows them to get the best treatment available, along with treatments that are thought to be even better.

With any cancer, how well a child is expected to recover (prognosis) varies. Keep in mind:

• Getting medical treatment right away is important for the best prognosis. Cancer that has spread is harder to treat.
• Ongoing follow-up care during and after treatment is needed.
• New treatments are being tested to improve outcomes and to reduce side effects.

Your child may receive additional low-dose I.V. chemo or oral medicines after the completion of standard therapy in order to keep the Ewing sarcoma from coming back. This is called maintenance therapy.

A child may have complications from Ewing sarcoma or from treatment, such as:

• Infection
• Bleeding
• Loose or broken grafts or rods from limb-salvage surgery
• Amputation of an affected limb if limb-salvage surgery is unsuccessful
• Hair loss, mouth sores, nausea, vomiting, diarrhea, increased infections, easy bruising and bleeding, and feeling tired from chemotherapy
• Burns, hair loss, nausea, diarrhea, poor bone growth, organ damage, and new cancers from radiation therapy
• Emotional and physical challenges from dealing with cancer, surgery, or other needed treatments
• Heart and lung problems
• Problems with growth and development
• Learning problems
• Changes in sexual development
• Problems having children in the future (infertility)
• The cancer comes back
• Growth of other cancers later in life

A child with Ewing sarcoma needs ongoing care. Your child will be seen by oncologists and other doctors to treat any late effects of treatment and watch for signs or symptoms of the tumor returning. Your child will be checked with imaging tests and other tests. And your child may see other doctors for problems from the tumor or from treatment. For instance, your child may need therapy to help with movement and muscle strength. This may be done by physical and occupational therapists.

You can help your child manage treatment in many ways. For instance:

• Your child may have trouble eating. A dietitian may be able to help.
• Your child may be very tired. They will need to balance rest and activity. Encourage your child to get some exercise. This is good for overall health. And it may help to reduce tiredness.
• Get emotional support for your child. A counselor, psychologist, or child support group can help.
• Make sure your child attends all follow-up appointments.

Contact the doctor if your child has:

• Symptoms that get worse or don't get better with treatment.
• New symptoms.
• Side effects from treatment.
• Signs of infection, such as fever or chills.
• Shortness of breath.
• Changes in how their urine looks or smells.

Your child's treatment team will talk with you about what you should look for and when to call them. Be sure you know how to get help if you have problems or questions after office hours or on weekends or holidays.

• Ewing sarcoma is a rare group of cancers that often start in the bone but can also start in soft tissue.
• X-ray and other imaging tests may be used to diagnose Ewing sarcoma. A biopsy is needed to make a definite diagnosis.
• Ewing sarcoma is often treated with chemotherapy followed by surgery or radiation therapy. High-dose chemotherapy and stem cell transplant may be used in some children.
• Ongoing follow-up care during and after treatment is needed.
• Many complications can result from the cancer and from the treatment. These may be short-term or long-term problems.

Tips to help you get the most from a visit to your child's doctor:

• Know the reason for the visit and what you want to happen.
• Before your visit, write down questions you want answered.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you for your child.
• Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are and when they should be reported.
• Ask if your child's condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if your child does not take the medicine or have the test or procedure.
• If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your child's doctor after office hours and on weekends and holidays. This is important if your child becomes ill and you have questions or need advice.