Treatment of Ewing tumors by stage

Treatment of a Ewing tumor is based mainly on the location and extent of the tumor at the time it is first found.

Localized Ewing tumors

As mentioned earlier, many children with localized Ewing tumors may still have spread of the cancer to other parts of the body that is too small to be seen with imaging tests. If these children do not get chemotherapy, these small metastases would eventually become larger tumors. This is why chemotherapy, which can reach all parts of the body, is an important part of treatment for localized Ewing tumors.

After the Ewing tumor is diagnosed, the first treatment is chemotherapy. It is called neoadjuvant chemotherapy because it is given before any surgery or radiation therapy. Treatment is usually a regimen known as VAC/IE, which is a combination of vincristine, doxorubicin (Adriamycin), and cyclophosphamide, alternated with ifosfamide and etoposide, although other combinations of the same drugs are also effective.

After at least 12 weeks of chemotherapy, imaging tests such as CT, MRI, PET, or bone scans are done to see if the tumor is shrinking and can be surgically removed.

If so, surgery is done at this point. If cancer cells are found at the edges of the surgery specimen (meaning cancer cells may have been left behind), radiation therapy and chemotherapy (for several months) are used. If there are no cancer cells at or near the edges of the surgery specimen, chemotherapy may be used without radiation therapy.

If the tumor is not growing but surgery is not an option after the initial chemotherapy, radiation therapy (along with chemotherapy) is usually the next treatment given. In some cases this may shrink the tumor enough so that surgery can then be done. This would then be followed by more radiation and chemotherapy. In other cases where surgery is still not an option, radiation therapy and chemotherapy are the main treatments.

If the Ewing tumor continues to grow despite the initial chemotherapy, a second type of chemotherapy (using different drugs) may be tried. Surgery or radiation therapy may also be tried to help keep the tumor under control. This may be followed by more chemotherapy.

Metastatic Ewing tumors

Patients who have metastatic disease when they are first diagnosed are harder to treat than patients with localized disease. The prognosis is better when the spread of cancer is limited to the lungs, as opposed to when the cancer has spread to other bones or to the bone marrow.

Treatment for metastatic disease is similar in many ways to the treatment for localized disease, but it may be more intense. Chemotherapy is the first treatment, often using a more intense regimen than would be used if the cancer was localized. After a few months, tests such as CT or MRI scans, bone or PET scans, and/or bone marrow biopsies are done to see how the cancer has responded to treatment.

If the cancer has only spread to a few small areas, the main (primary) tumor and all known areas of metastases may be removed with surgery at this point. Other options, such as surgery plus radiation therapy or radiation therapy alone to all known metastatic sites, including the lungs, might also be tried. During and after these treatments, chemotherapy is given for several months as well.

Doctors at several cancer centers are now studying giving very intensive chemotherapy followed by a stem cell transplant to try to improve the outcome for these patients. For more information on this procedure, see the "High-dose chemotherapy and stem cell transplant" section of this document.

Because these tumors can be hard to treat, clinical trials of newer treatments may be a good option in many cases.

Ewing tumors that recur (come back) after treatment

Recurrence of Ewing tumors after treatment is less likely than in the past, but it can happen. If the tumor does recur, treatment may depend on a number of factors, including

• The size and location of the tumor
• Whether it has spread to different parts of the body
• What types of treatment were used before
• How long it has been since treatment

Chemotherapy, surgery, radiation therapy, or some combination of these may be used to treat recurrent tumors, depending on the situation. Doctors are also studying the use of high-dose chemotherapy followed by a stem cell transplant and the use of targeted drugs called monoclonal antibodies, but it is not yet clear how useful these are. Treating these tumors can be difficult, so clinical trials of newer treatments may be a good option.