Ewing's sarcoma

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at April 20, 2016
StartEwing's sarcoma

A fairly unusual type of cancer that mainly affects those under 20 years of age, Ewing's sarcoma involves malignant tumors on the bone or in the surrounding soft tissue, and must be treated systemically (the whole body) to make sure it cannot spread or to kill off cancer cells that may have already spread to other parts of the body.

Contents

Definition & Facts

Ewing's sarcoma is a cancer that primarily targets young people with the most common ages for developing the disease occurring between ages 10 and 20 years old. It starts either in the soft tissue around a bone or – more commonly – as a tumor on a bone, and is most commonly found in the trunk, pelvic area, ribs, spine, and thighs; occasionally, a tumor may develop on the skull.

The tumor can metastasize and spread to the lungs, bone marrow, and other bones. This cancer is more common in Caucasian children than any other ethnicity, and most often develops during periods of rapid growth, although it is not known why. If Ewing's sarcoma is detected and treated early, the prognosis is good, but even if the tumor found is tiny, the entire body must be treated with chemotherapy in case the cancer has spread through the blood. About one-third of the patients with this cancer are not diagnosed until the cancer has already spread.

Catching Ewing's sarcoma early and treating it with surgery for the primary tumor, preceded or followed by chemotherapy and radiation, is the most successful way of making sure that all the cancer has been eradicated. Even though Ewing's sarcoma is the second most common kind of bone cancer in children, it is still considered a rare cancer, seen annually in the U.S. in only about 200 children/young adults.

About 70% of Ewing's sarcoma patients are cured with early intervention and aggressive treatment, although the survival rate for patients ages 15-19 is lower, somewhere between 55 and 60%. Children in whom the cancer has spread have a 30% rate of survival, and tumors that occur in the ribs, spine or pelvic area are less likely to be cured.

Symptoms & Complaints

The most common signs of Ewing's sarcoma are pain and swelling, which are both broad problems that can be attributed to many physical issues and easily overlooked. The pain and swelling that accompanies this cancer, if left untreated, can also weaken the bones and sometimes cause bone fractures.

In young people, swelling is often present in the long bones of the legs and arms while a tumor may not cause any pain at all unless it is located on or near sensitive nerves in the pelvis or spine, in which case it may become extremely painful. Some patients develop anemia, and some experience symptoms like fatigue, unexplained weight loss, and unexplained fever. It is important to get these symptoms evaluated by a doctor since none of these symptoms necessarily indicate cancer at all.

Causes

The cause of Ewing's sarcoma is unknown, but what is known is that the cells that produce this type of blood cancer resemble early, immature cells in the body that would normally develop to become part of the central nervous system. Some researchers believe there may be a genetic factor, but this has not been proven.

Diagnosis & Tests

If the doctor suspects a bone tumor, he or she will perform a thorough medical exam including a blood test for markers that indicate increases in certain enzyme levels in the blood that are indicative of cancer. Other tests may include imaging (X-rays or MRIs), and if a tumor is found, then some tissue from the site will be removed and biopsied.

The Ewing's sarcoma cancer cells are small, round and blue, and in order to differentiate them from other similar cancer cells, further lab tests including using stains on the cells can be used in diagnosing the disease.

Treatment & Therapy

The malignant tumors can spread throughout the body easily, and because of this, there is no way that surgery – even with clear margins – can guarantee that the cancer has been eradicated. This means that the Ewing's sarcoma patient will have to be treated for possible metastasis to other parts of the body. This involves using chemotherapy, which can shrink a tumor before removal, and to destroy tumor cells that have spread. The surgery to remove the tumor may occur before other treatment or after chemo treatment has caused the tumor to shrink.

Radiation therapy is localized to the area where the tumor is or was located, and it kills cancer cells by targeting the primary tumor area and using high-dose radiation to kill any living cancer cells there. A newer, alternative method of radiation called internal radiation uses needles, seeds, or wires implanted near the site of the tumor to kill off cancer cells.

Sometimes a surgeon will have to add (graft) bone or tissue to replace the diseased tissue and/or bone that have been removed. Sometimes amputation of a limb is necessary in order to make sure the tumor is completely removed.

Prevention & Prophylaxis

Because relatively little is known about the cause of this cancer, there is no preventative or prophylactic action that can be taken to keep it from developing. Of course, the normal advice (healthy diet, regular exercise, weight maintenance) applies just as it does in any other case.

Parents and young people themselves have to pay attention and take note if there is unusual or recurring pain in the abdomen, thighs or pelvic areas. If the pain doesn’t go away in a reasonable amount of time, it should be checked out.

Or if the young person in question has an unexplained fever or feels weak, or if there is a broken bone that seems like it shouldn’t have broken, take the time to have a doctor check out the symptoms and perform some tests. Even though Ewing's sarcoma is not a common cancer, being aware that it exists and what the symptoms are can assist in early treatment.