Ewing sarcoma is a type of bone cancer. However, it can also begin outside of the bones in the body’s soft tissues.

Ewing sarcoma is a rare type of cancer that usually develops in bone cells, but it may also form in soft tissues.

Ewing sarcoma is part of a group of tumors that doctors call the Ewing family of tumors.

This article looks at what Ewing sarcoma is, its prevalence, its outlook, and more.

A doctor walking with a child with Ewing sarcoma, a type of bone cancer.Share on Pinterest
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Ewing sarcoma is a rare type of bone cancer. It is a type of tumor that usually starts to develop in the bone. It is more common in children and young adults and may first appear during the teenage years.

In some cases, Ewing sarcoma may begin in the soft tissues and muscles rather than the bones. Doctors refer to this as extraosseous Ewing sarcoma.

The cause of Ewing sarcoma is unclear, but changes in the DNA of cells may cause bone cells to become cancerous.

People with Ewing sarcoma may have changes on chromosome 22 involving the EWSR1 gene. Individuals do not inherit these genetic changes, but they may occur after a child is born.

These changes cause the EWSR1 gene to “activate” constantly, causing cells to grow more than they would typically. This may cause Ewing sarcoma.

Bone cancer is an uncommon type of cancer that begins in the bones. The disease starts when cells in the bone begin to grow uncontrollably.

Primary bone cancer is cancer that begins in bone cells. These types of bone cancers, or bone sarcomas, include:

Secondary bone cancers are cancers that start in a different organ of the body and spread, or metastasize, to the bone.

Benign tumors can also occur in the bone — these are noncancerous. These include osteomas, osteoblastomas, and osteochondromas.

Ewing sarcoma can affect any part of the skeleton but usually occurs in the following areas:

  • the femur, or thighbone
  • the tibia, or shinbone
  • the humerus, or upper arm bone
  • pelvic or hip bones
  • bones in the chest area, such as the shoulder blades and ribs
  • spinal bones

Ewing sarcoma can also form in soft tissues. Doctors call this extraosseous Ewing sarcoma.

Soft tissues are present all around the body and include:

  • muscle
  • fat
  • blood vessels
  • nerves

Ewing sarcoma most commonly affects teenagers and young adults through to the age of mid-20s.

According to the American Cancer Society (ACS), it is rare for people over 30 years of age to get Ewing sarcoma.

Ewing sarcoma is the second most common form of primary bone cancer that affects children, teenagers, and young adults. Overall, it is the third most common form of bone cancer.

Ewing sarcoma most commonly occurs in white people and is rare in African Americans or Asian Americans.

The National Organization for Rare Disorders (NORD) offers the following facts around Ewing sarcoma:

  • accounts for roughly 2% of all childhood cancers
  • accounts for roughly 70% of tumors in the Ewing family of tumors group
  • is more common in males than females
  • is most common in people between the ages of 10–20 years
  • may occur in 2.93 children per 1,000,000 each year
  • in the United States, around 200–250 children and adolescents may have a diagnosis of an Ewing family tumor each year
  • two-thirds of people with an Ewing family tumor will survive long-term, for more than 5 years
  • extraosseous Ewing sarcoma is more common in people over the age of 35 years or under 5 years

This section answers some frequently asked questions about Ewing sarcoma.

Is sarcoma always bone cancer?

A sarcoma is not always a type of bone cancer.

The two main types of sarcomas are bone sarcomas and soft tissue sarcomas. However, sarcomas can occur anywhere in the body.

Sarcomas can start developing in:

  • bone
  • fibrous tissues
  • muscle
  • blood vessels
  • fat

How is Ewing sarcoma different from osteosarcoma?

Osteosarcoma is the most common type of bone cancer. It usually affects long bones in the arms and legs. It is more common in children, adolescents, and males.

Osteosarcoma mostly occurs around the knee. In contrast, Ewing sarcoma usually affects the lower leg, thigh, pelvis, upper arm, or rib. Both conditions may cause pain and swelling in the affected area.

How serious is Ewing’s sarcoma?

The outlook for Ewing’s sarcoma has significantly improved over time due to advances in diagnostic tests and improvements in treatments.

A person’s outlook may vary depending on the stage of the tumor. The 5-year relative survival rate for Ewing’s sarcoma is 62% for all stages combined.

This means that people with Ewing’s sarcoma are, on average, about 62% as likely to live for at least 5 years after their diagnosis as those without cancer.

Those with a localized Ewing tumor — one that has not spread to other areas — may have a 5-year survival rate as high as 82%.

Ewing sarcoma is a rare type of cancer that begins in the bones. In some cases, it may also start outside the bones in soft tissues.

Ewing sarcoma may cause pain and swelling in the affected area. It usually occurs in the legs, upper arms, pelvis, or ribs. Ewing sarcoma is more common in children and adolescents.

Treatments for Ewing sarcoma may include surgery, chemotherapy, and radiation therapy.