Ewing sarcoma is a cancerous tumor that grows in bones or soft tissue near bones and usually affects adolescents.
Named after Dr. James Ewing, the American pathologist who identified the cancer in the 1920s, it can develop anywhere in the body, but most commonly affects the arms, legs, ribs, spinal column, and pelvis.
Treatment for Ewing sarcoma involves a combination of chemotherapy, surgery, and/or radiation. With early diagnosis and proper treatment, many kids who develop it have a good chance of recovery.
Signs and Symptoms
Ewing sarcoma often goes unnoticed or misdiagnosed as growing pains (due to its subtle, gradual onset) or a sports injury because symptoms often mimic those of injuries kids can get out on the field.
Soreness at the tumor site, accompanied by swelling or warmth, is common. Pain may be worse during exercise or at night, and a tender lump may develop in the affected area a few weeks after pain begins. If the tumor grows in a leg bone, the child may have an unexplained limp. A low-grade fever also can develop.
If cancer has spread, or metastasized, to other areas of the body like the lungs or bone marrow, symptoms may appear there as well. In some cases, the first sign of the disease is a broken arm or leg that occurs for no reason at all (or after a minor accident) because the cancer has weakened the bone, making it vulnerable to a break.
A child who experiences any of these symptoms should see a doctor as soon as possible. Waiting to seek treatment or assuming that symptoms will resolve on their own without treatment may lead to a more advanced form of the disease at diagnosis.
To diagnose Ewing sarcoma, a doctor will ask for your child's medical history, perform a physical examination, and order X-rays, an MRI (magnetic resolution imaging), or bone scans to detect abnormalities in bone structure. A tissue sample of the tumor (biopsy), which is later analyzed in a lab, must be performed in order for a diagnosis to be made.
Sometimes the doctor orders a needle biopsy, using a long hollow needle to take a sample of the tumor. Alternatively, the doctor may order an open biopsy, in which a portion of the tumor is removed. These are performed in the operating room by a surgeon while a child is under general anesthesia.
If a diagnosis of Ewing sarcoma is made, the doctor will order additional imaging tests to determine if the cancer has spread to any other part of the body. Other exams will make sure that vital organs, such as the heart and kidneys, are functioning normally and able to tolerate treatment.
Once treatment begins, doctors monitor the patient and order additional imaging tests to determine how well it is working and whether the cancer continues to spread.
The course of treatment for Ewing sarcoma depends on many factors, including the size and location of the tumor and whether the disease has metastasized.
Regardless of a tumor's characteristics, every patient with Ewing sarcoma undergoes chemotherapy initially to shrink the tumor (before surgical removal or radiation) and prevent the spread of cancer cells to other parts of the body. Chemotherapy is also given after a tumor is removed to help ensure that cancer cells do not come back.
A typical course of chemotherapy lasts 6 to 9 months. Children are required to stay in the hospital for a few days during treatment, which occurs every 2 to 3 weeks. Some kids may need to be hospitalized between treatments for complications or side effects, like fever or infection. Chemotherapy drugs are delivered intravenously (through a vein).
If surgery is needed, radiation may be given to shrink the tumor before surgical removal. Radiation also may be recommended in place of surgery if the tumor's location would make surgery too dangerous or difficult. During radiation, high-energy X-rays are directed at the tumor site to kill cancer cells and keep them from growing and multiplying.
Most kids who undergo radiation don't need to stay at the hospital overnight; they usually visit the hospital 5 days a week for several weeks.
After a course of chemotherapy, and possibly radiation, most tumors are removed surgically. Tissue that is removed during the procedure may need to be replaced with a live tissue graft (from the patient's own body), donor tissue (usually from a bone bank), or artificial tissue (made from metal or other synthetic material).
If a tumor has attached itself to nerves and blood vessels, amputation (removing part of a limb along with the tumor) might be the only choice. The amputated limb will be replaced with an artificial limb, usually made from metal.
Amputation carries its own short- and long-term side effects. It usually takes at least several months until a young person learns to use a prosthetic leg or arm. Learning to cope with the psychological and social aspects takes longer, but many children find they can resume favored activities in the long run.
With a tissue graft (donor or otherwise), one usually starts moving the affected body part almost immediately. Physical therapy and rehabilitation for 6 to 12 months after surgery usually helps a child recovering from Ewing sarcoma of the leg to walk, initially with a walker or crutches, and then without assistive devices.
Early complications after surgery include infection and slow healing of the surgical wound, and the metal prosthetic device or the bank bone might need to be replaced in the long term. Other late problems might include fracture of the bank bone or failure of the bank bone to heal to the child's bone, which might require more surgery. Some kids will be limited in the types of sports they can play due to the risk of breakage.
Many chemotherapy medications also carry the risk of both short- and long-term problems. Short-term effects include anemia, abnormal bleeding, and increased risk of infection due to destruction of the bone marrow, as well as kidney, liver, or heart damage. Some drugs carry a risk of bladder inflammation and bleeding into the urine. Years after chemotherapy for Ewing sarcoma, patients have an increased risk of developing other cancers and may have difficulties with fertility.
A child with Ewing sarcoma who is diagnosed early on and does not have metastatic disease has up to a 70% chance of being cured of the cancer.
When the disease has spread, successful treatment is much more difficult. However, with the potent combination of treatments currently available — and powerful new therapies on the horizon — the outlook for kids with advanced disease is improving.