Ewing's Sarcoma Health Article

Definition

Ewing's sarcoma is a cancer that affects children, teens, and less often, young adults. It begins in developing bone cells. Ewing's sarcoma cells grow uncontrollably and form masses or lumps called tumors. They can start in any bone in the body but about half of all cases involve flat bones such as the pelvic bones and the long bones in the leg—the tibia, fibula, and femur.

Description

Ewing's sarcoma is the second most common bone tumor among children and teens. It accounts for about 1% of all childhood cancers. This cancer is named for James Ewing, the researcher who first described the tumor in 1921. There are some rare cases of Ewing's sarcoma that do not begin in bones. These tumors are thought to start in nerve or other soft tissues.

Demographics

Ewing's sarcoma occurs most frequently in children ages 11 to 15 years old. Slightly more males than females develop Ewing's sarcomas, and like osteosarcoma, the most common bone cancer found in children, it is more often diagnosed in taller teens. The disease is rarely diagnosed in children younger than 5 or adults older than 30. It affects primarily Caucasians, and rarely occurs in African Americans and native Chinese.

Causes and symptoms

The causes of Ewing's sarcoma are not known. It is possible that certain inherited conditions increase the risk of developing this cancer.

About two-thirds of patients with Ewing's sarcoma have a painful swelling or lump that can be felt in the affected bone. Along with tenderness, the area of swelling may be hot. The symptoms depend on the site of the tumor and whether it has spread. For example, a tumor on a rib may cause painful breathing. When Ewing's sarcoma has spread, patients may have other symptoms such as fatigue, weight loss, and fever.

Diagnosis

Most patients who have Ewing's sarcomas go to the doctor because they have discovered a lump or mass or swelling on or near a bone. Others have symptoms related to the part of the body that is affected by the tumor, such as pressure on the bladder from a tumor on a pelvic bone.

The patient's doctor will take a detailed medical history to find out about the symptoms. The history is followed by a complete physical examination with special attention to the suspicious symptom or body part.

Depending on the location of the tumor (mass or lump), the doctor will order imaging studies such as x ray, computed tomography (CT) scans and magnetic resonance imaging (MRI) to help determine the size, shape and exact location of the tumor. The doctor will also order a chest x ray to find out if the tumor has spread to the lungs, and bone scans to determine if the tumor has spread to bones. Blood tests will be done and an examination of the bone marrow will be performed to see if the marrow is involved.

A biopsy of the tumor is necessary to make a diagnosis of Ewing's sarcoma. During a biopsy, some tissue from the tumor is removed. The tissue sample is examined by a pathologist, a doctor who specializes in the study of diseased tissue.

Types of biopsy

The type of biopsy done depends on the location of the tumor. For some small tumors, such as those on the arm or leg, the doctor may perform an excisional biopsy, removing the entire tumor and a margin of surrounding normal tissue. Most often, the doctor will perform an incisional biopsy, a procedure that involves cutting out only a piece of the tumor. This biopsy provides a core of tissue from the tumor that is used to confirm the diagnosis of Ewing's sarcoma.

Treatment team

Like other cancer patients, teens and young adults with Ewing's sarcoma are usually cared for by a multidisciplinary team of health professionals. The patient's pediatrician, family physician, or primary care doctor may refer the patient to other physician specialists, such as surgeons and oncologists (doctors who specialize in cancer medicine). Radiologic technicians perform x ray, CT and MRI scans and nurses and laboratory technicians may obtain samples of blood, urine and other laboratory tests.

Before and after any surgical procedures, including biopsies, specially trained nurses will explain the procedures and help to prepare patients and families. Depending on the tumor location and treatment plan, patients may also benefit from rehabilitation therapy with physical therapists and nutritional counseling from dieticians.