Treatment of Ewing Tumors by Stage

Treatment of a Ewing tumor (Ewing sarcoma) is based mainly on where it is in the body and how far it has spread when it's first found.

Localized Ewing tumors

A localized Ewing tumor is one that still appears to be confined to the area where it started (and maybe also to nearby tissues such as muscle or tendons), based on imaging test and biopsy results. But even people with localized Ewing tumors often still have small areas of cancer in other parts of the body that can't be seen with imaging tests. If these people don't get chemotherapy (chemo) as part of their treatment, these small areas of cancer cells would eventually become larger tumors. This is why chemo, which can reach all parts of the body, is an important part of treatment for localized Ewing tumors.

Once the Ewing tumor has been diagnosed and staged, the first treatment is chemotherapy. It's called neoadjuvant chemotherapy because it's given before any surgery or radiation therapy. In the United States, patients are given a chemo regimen known as VDC/IE (or 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 9 weeks of chemo, imaging tests such as CT, MRI, PET, or bone scans are done to see if the tumor is shrinking (or at least isn't growing) and if it can be surgically removed. If so, surgery is done at this point. The surgery specimen is then sent to a lab to be looked at by a doctor called a pathologist.

• If cancer cells are found at or near 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 can be used without radiation therapy.

If surgery is not an option after the initial chemotherapy (because of the tumor location or some other reason), but the tumor is not growing, radiation therapy (along with chemotherapy) is usually the next treatment given. In some cases this might shrink the tumor enough so that surgery can then be done. This would then be followed by more chemotherapy, possibly with more radiation as well. 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 clearly have metastatic disease when they are first diagnosed are harder to treat than patients with localized disease. The outlook tends to be better when the cancer has only spread to the lungs, as opposed to when the cancer has spread to other bones or to the bone marrow.

Treating metastatic disease is similar in many ways to treating localized disease. Chemotherapy is the first treatment, but it often requires 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 remains in only a few small areas after chemo, the main (primary) tumor and all known areas of metastases may be removed with surgery at this point. Other approaches, such as surgery plus radiation therapy (before and/or after surgery) or just radiation therapy to all known metastatic sites, might also be options. 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.

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 now than in the past, but it can happen. If the tumor does come back, treatment depends on a number of factors, including:

• The size and location of the tumor
• If 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 usefulness of high-dose chemotherapy followed by a stem cell transplant, as well as targeted drugs and immune therapies. These tumors can be hard to treat, so clinical trials of newer treatments may be a good option.