Ewing sarcoma develops due to genetic causes that include changes to a person’s DNA and chromosomes. It more often affects teenagers and young adults, males, and white people.

The exact cause of Ewing sarcoma is unknown, but researchers have discovered a link between genetics and the disease. The genetic changes happen once a person is born but do not appear to be inherited.

DNA, which plays a role in the cause of Ewing sarcoma.Share on Pinterest
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Researchers do not fully understand the causes of Ewing sarcoma. However, they have established links between Ewing sarcoma and genetic causes, including DNA changes and changes to chromosomes.

Chromosomes are structures located inside the nuclei of cells. A person typically has 23 pairs of chromosomes, each consisting of protein and a molecule of DNA. DNA carries each person’s genetic information. Genes instruct the cells in the body how to function, and some control when the cells grow, divide, and die.

Ewing sarcoma can develop due to chromosomal changes that happen in a single cell once a person is born. The reason for this change is unknown, but researchers have confirmed that it is not inherited.

The American Cancer Society (ACS) states that most Ewing tumor cells have genetic changes involving the EWSR1 gene, which is found on chromosome 22. The change usually involves the swapping of DNA between chromosomes 22 and 11. This is called chromosomal translocation.

When the chromosomal translocation occurs, a piece of chromosome 11 moves next to the EWSR1 gene on chromosome 22. This causes the EWSR1 gene to be activated constantly, resulting in cell overgrowth and the development of an Ewing sarcoma tumor.

Although the most common chromosomal translocation affects chromosomes 11 and 22, Ewing sarcoma can also develop when chromosomes 22 and 21 are affected. Rarely the swap can affect chromosome 22 and another chromosome.

Risk factors increase a person’s chance of developing a condition. It is important to remember that having a risk factor does not mean that a person will develop Ewing sarcoma.

Risk factors for Ewing sarcoma include:

  • Age: Although anyone can develop Ewing sarcoma, the National Library of Medicine (NIH) notes that Ewing sarcoma most commonly affects children and adolescents, often between the ages of 10 and 15. The article states that 30% of cases develop in children under the age of 10, and 30% of cases develop in adults over 20.
  • Sex: Ewing sarcoma more commonly affects males.
  • Race and ethnicity: Ewing sarcoma most commonly affects white people. However, the reason for this is unclear.

Can environmental and lifestyle factors increase the risk of Ewing sarcoma?

There does not appear to be an association between Ewing sarcoma and environmental or lifestyle factors. The NIH states that there does not appear to be a well-established association between the cancer and the following:

  • environmental risk factors
  • drug exposure
  • a family history of cancer
  • a history of radiation

Can other medical conditions increase the risk of Ewing sarcoma?

There does not appear to be an established connection between Ewing sarcoma and other medical conditions. The cause of Ewing sarcoma is genetic, and risk factors include age, sex, and race.

There is no known way to prevent Ewing sarcoma from developing.

For other cancers, a person may be able to lower the risk of developing the disease by making certain lifestyle changes. However, the known risk factors for Ewing sarcoma are age, sex, and race.

What are the most common sites where Ewing sarcoma develops?

Although Ewing sarcoma can develop in nearly any bone or soft tissue, it most commonly affects the:

  • pelvis
  • thigh bone (femur)
  • central part of the skeleton (axial skeleton)

How common is Ewing sarcoma?

Ewing sarcoma is uncommon. The ACS states that Ewing sarcoma accounts for 1% of all childhood cancers, and 200 children and teenagers receive a diagnosis of Ewing sarcoma each year in the United States.

Ewing sarcoma makes up 10% to 15% of all bone sarcomas.

The exact cause of Ewing sarcoma is unknown. However, researchers have established a link between the development of Ewing sarcoma, genetic changes, and chromosomes.

The most common DNA change that causes Ewing sarcoma is the swapping of DNA between chromosomes 22 and 11. The piece of chromosome 11 moves next to the EWSR1 gene on chromosome 22, resulting in cell overgrowth, which causes the development of the tumor.

It typically affects teenagers and young adults and appears to be more common in white people and males.