Soft Tissue Sarcomas

  • What are soft tissue sarcomas?

    Soft tissue sarcomas are malignant tumors that begin in soft tissue, such as muscle, fibrous tissues, tendons, fat, nerves, joint tissues and blood vessels.

    These tumors are rare and can form anywhere in the body. Usually, only about 900 cases of soft tissue sarcomas are reported in children each year in the United States.

    Often painless, soft tissue sarcomas can be present in the body for a long period of time before they are discovered.

    There are several types of soft tissue sarcomas that involve joints, bones and nerves. They include:

    • Rhabdomyosarcoma — a tumor of skeletal muscles and the most common soft tissue sarcoma
    • Infantile fibrosarcoma — found in tissue that forms tendons and ligaments
    • Malignant fibrous histiocytoma — found in the fibrous tissue in the legs (Histiocyte cells are part of the immune system which fights infection.)
    • Peripheral nerve sheath tumor — found in cells that surround nerves
    • Synovial cell sarcoma — found in tissue around joints, usually the knee

    A few soft tissue sarcomas do not involve bones or joints. These include:

    • Leiomyosarcoma — usually found in the stomach, bowels, uterus and blood vessels
    • Liposarcoma — found in the fat tissue of the stomach

    Studies have identified a connection between soft tissue sarcomas and other cancers. Certain conditions, such as inherited diseases like Li-Fraumeni syndrome or neurofibromatosis, as well as the infectious virus Epstein-Barr, have been linked to an increased risk of developing soft tissue sarcomas.

  • Causes

    The cause of soft tissue sarcomas is unknown, but there may be a genetic reason for their formation.

  • Signs and symptoms

    Symptoms of soft tissue sarcomas can include:

    • Painless swelling or a lump
    • Pain or soreness due to the tumor compressing nerves or muscles
    • A limp, or difficulties moving legs or arms 
  • Testing and diagnosis

    Symptoms of soft tissue sarcomas can be difficult to identify in children, so regular check-ups are extremely important. Prompt diagnosis and identification of cancer as early as possible is crucial to overall treatment.

    Diagnostic evaluation begins with a thorough medical history and physical examination of your child. A detailed neurological assessment may also be performed.

    At The Children’s Hospital of Philadelphia, clinical experts use a variety of diagnostic tests to diagnose tumors, including:

    • X-rays, which produce images of bones.
    • Magnetic resonance imaging (MRI), which uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body.
    • Computed tomography (CT) scan, which uses a combination of X-rays and computer technology to produce cross-sectional images ("slices") of the body.
    • Radioisotope bone scan, which can help locate areas of abnormal growth.
    • Blood tests, which can help determine drug usage and effectiveness, biochemical diseases and organ function.
    • Biopsy, which is a surgical procedure to take a sample of the growth, may be necessary to confirm any findings.
    • EOS imaging, an imaging technology that creates 3-dimensional models from two planar images. Unlike a CT scan, EOS images are taken while the child is in an upright or standing position, enabling improved diagnosis due to weight-bearing positioning.
  • Treatments

    Treatment for soft tissue sarcomas varies, depending on the location and size of the tumor. 


    Surgical treatment for soft tissue tumors may be used alone or in conjunction with chemotherapy or radiation therapy. 

    Surgeries performed are typically:

    • Wide resection with margins
    • Resection and reconstruction

    In a wide resection with margins, the tumor is surgically removed, as well as some of the healthy tissue that surrounded the tumor — the margins of the tumor. In some cases, the child will need reconstructive surgery after the tumor has been cut out.

    Reconstructive surgery

    Reconstruction can include:

    • Endoprosthetics, which can be expanded as the child grows
    • Free vascularized fibular grafting, which includes moving one bone from your child's lower leg to replace a diseased thigh bone
    • Amputation of a limb 
    • Other

    Surgical safety

    Though surgery for soft tissue tumors is highly effective, we understand that any surgery can be a stressful experience for your child and family. At CHOP, we offer a wealth of resources about how to prepare your child for surgery and what to expect during surgery. Download CHOP's Having Surgery booklet. (PDF)

    Additionally, we employ numerous best practices before, during and after surgery to decrease the risk of infection and increase positive outcomes. For more details about safety protocols at The Children's Hospital of Philadelphia, see safety in surgery


    Chemotherapy refers to medicines that help fight cancer. They are given to your child orally (by mouth) or injected into a vein, muscle or under the skin. Intrathecal chemotherapy is chemotherapy that is injected into the spinal fluid to prevent or treat a malignant tumor in the brain and spinal cord.

    Radiation therapy

    Radiation therapy uses high-energy waves such as X-rays to kill or shrink cancer cells. It is sometimes used to treat cancer in the central nervous system or other places such as the eye or the testes.

  • Follow-up care

    Most children are able to go home shortly after surgery. They may require pain medications until the surgical site heals or ongoing physical therapy, but most are encouraged to resume their regular daily activities, like school, social events and play.

    Your child will see the orthopedic surgeon about one to two weeks after surgery, then again at three and six months post-surgery. Annual monitoring by trained clinicians is strongly encouraged to monitor for possible reoccurrence of the growth.

    Malignant tumors can reoccur — even after being successfully treated — so it is important for your child to see a physician regularly, especially if any symptoms reoccur.

    During follow-up visits, X-rays and other diagnostic testing of the tumor site are recommended to closely monitor your child’s health and ensure there are no side effects from surgery, chemotherapy or radiation therapy.

    Follow-up care and ongoing support and services are available at our Main Campus and throughout our CHOP Care Network. Our team is committed to partnering with parents and referring physicians to provide the most current, comprehensive and specialized care possible for your child.

  • Outlook

    As with any cancer, survival depends on the type of cancer, the age of your child, how much the tumor has grown and how well your child tolerated treatment.

    However, studies have shown that the younger your child is when diagnosed, the better the outcomes.

Reviewed by Jason L. Katz, PA-C, MHS, ATC-R on May 20, 2014