Desmoid Tumor

Desmoid tumor is a rare type of cancer that develops in the tissues that form tendons and ligaments, usually in the arms, legs or abdomen and sometimes in the chest. These tumors, also called aggressive fibromatosis, are considered benign because they typically don't spread to other parts of the body. They may invade nearby tissues and organs, however, and can be difficult to control.

Although the cause of these tumors is not known, researchers have found that they tend to occur in children who have a family history of polyposis coli, a hereditary colon cancer. Treatment options include surgery, chemotherapy and radiation, depending on the location of the tumor and your child's age.

A Desmoid tumor may exist for some time before being discovered. That's because they develop in flexible tissue such as tendons and ligaments, which are pushed aside to make room as the tumors grow. Symptoms vary with each child, but common symptoms include:

  • Painless swelling or lump
  • Obstruction of the bowels, when tumors form in the abdomen
  • Pain or soreness caused by compressed nerves or muscles
  • Limping when the tumors occur in the legs

Desmoid tumors vary greatly depending on size and location of the tumor, the extent to which it has invaded surrounding tissues and your child's age.

The most conclusive diagnostic procedure for Desmoid tumor is a biopsy, a tissue sample from the tumor taken through a simple surgical procedure. Magnetic resonance imaging (MRI), computed tomorgraphy (CT) scans and X-rays also are used in the diagnosis and may be performed after your child has had a completed medical examination.

Treatment options include surgery, radiation, chemotherapy and hormone therapy.


Surgery to remove the tumor is the primary treatment for a Desmoid tumor. Because these tumors rarely spread or metastasize, surgery alone often is the only necessary treatment. However, Desmoid tumors have a high recurrence rate, meaning they return after treatment, if they aren't completely removed. Frequently, more than one surgery is needed.

Radiation therapy

Radiation therapy uses high-energy radiation from X-rays or other sources to kill cells and shrink tumors. Radiation may be used alone or in conjunction with surgery.

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Reviewed by health care specialists at UCSF Benioff Children's Hospital.

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