Soft tissue sarcomas occur in connective tissues throughout the body. These connective tissues include muscle, cartilage, tendons, fat, nerves, joint tissues and blood vessels.
Malignant soft tissue sarcoma can spread to other parts of the body. These tumors can grow back even after they have been removed or treated with other therapies.
What Causes Soft Tissue Sarcoma?
Experts do not know what causes soft tissue sarcoma. Most soft tissue sarcomas are not linked with hereditary factors. But people with certain genetic diseases may be at a higher risk of developing soft tissue sarcoma. These diseases include:
- Li-Fraumeni syndrome
- Tuberous Sclerosis
- Werner Syndrome
- Familial Adenomatous Polyposis
Prior radiation treatment may put people at a higher risk for soft tissue sarcoma as well.
What Are the Signs and Symptoms of Soft Tissue Sarcoma?
Connective tissue is soft and flexible and can “hide” the presence of soft tissue sarcoma. The cancer may be there for a long time before it is found.
Symptoms that may point to soft tissue sarcoma include:
- A lump or swelling that may or may not be painful
- Other symptoms may vary widely depending on the location and size of the mass.
How Common Is Soft Tissue Sarcoma?
Soft tissue sarcomas are relatively common. Each year, about 12,000 people in the United States are diagnosed with soft tissue sarcoma. About 1,000 of those are children.
How Are Soft Tissue Sarcomas Diagnosed?
The first step in diagnosing soft tissue sarcoma is for the doctor to take a detailed medical history of the patient and their family. Next, the patient has a physical exam and other types of tests, which may include:
- Magnetic resonance imaging (MRI)
- Computed tomography (CT)
- Positron emission tomography (PET), which measures important body functions and also can show whether the cancer has spread
- Bone scans
- Blood tests
- A needle biopsy or surgical procedure. A specialist examines the tissue under a microscope to confirm the diagnosis of soft tissue sarcoma.
These tests allow the doctor to see where the tumor is located, its size, and if it has spread to other parts of the body. The team uses all this information to create a personalized treatment plan.
What Are the Types of Soft Tissue Sarcomas?
There are two types of sarcoma: bone and soft tissue. There are over 50 types of soft tissue sarcomas. Sarcoma experts classify soft tissue sarcoma based on where the cancer is located in the body.
The most common types of soft tissue sarcomas include:
- Rhabdomyosarcoma − found in the muscles
- Synovial sarcoma − found in tissue around joints and other connective tissue
- Desmoplastic small round cell tumors (DSRCT) − usually found in the abdomen or pelvis
- Epithelioid sarcoma − most commonly found in the extremities
- Infantile fibrosarcoma − found in connective tissue
- Malignant fibrous histiocytoma − found in connective tissues
- Malignant peripheral nerve sheath tumor − found in the tissue that surrounds nerves
- Desmoid tumor (also called aggressive fibromatosis) − found in connective tissues is not a cancer
What Are the Stages of Soft Tissue Sarcoma?
Staging of soft tissue sarcoma is based on the size of the tumor and whether it has spread to lymph nodes or distant sites in the body. If the tumor has not spread, it is considered to be localized. Metastatic soft tissue means the tumor has spread past nearby tissues to lungs or other organs.
How Do Doctors Treat Soft Tissue Sarcoma?
Treatment for soft tissue sarcoma can include surgery, chemotherapy and/or radiation therapy.
The patient may have a procedure, called a wide resection with margins, to remove the tumor and some tissue around the tumor. If the doctor is concerned that the cancer has also spread to nearby lymph nodes, they may also be removed.
Patients may have radiation treatment before surgery to make the tumor smaller. After surgery, additional radiation therapy can help kill any tumor cells left in the body.
The doctor will make a plan for radiation based on the treatment goals and the location of the tumor.
Two types of radiation are used, regular radiation or proton radiation. Proton radiation has less side effects because it kills the tumor but does not hurt organs and healthy tissue. This means fewer short-term side effects and long-term complications from radiation. Cincinnati Children’s is one of the few pediatric hospitals in the country that offers proton therapy.
If the tumor is large or cannot be removed, the doctor may recommend chemotherapy or other types of drugs to help kill the cancer cells.
Clinical Research Trials
Soft tissue sarcoma can be challenging to treat. In some situations, the doctor may recommend participating in a clinical trial for children or adolescents and young adults at Cincinnati Children's.
Follow-up imaging tests can help monitor how the cancer is responding to treatment.
What Is the Long-Term Outlook for People with Soft Tissue Sarcoma?
Many factors affect the long-term outlook for patients with soft tissue sarcoma. These include:
- The size of the tumor
- Location of the tumor
- When it was discovered
- Whether it has spread
Patients are more likely to fully recover from a soft tissue sarcoma that is localized and is completely removed through surgery. Tumors that are large or have spread are generally associated with a less favorable outlook.
Prompt diagnosis and treatment are important for people diagnosed with soft tissue sarcoma. That is why it is very important for patients to receive specialized multidisciplinary care at a hospital such as Cincinnati Children’s.
Our sarcoma team has experience in diagnosing and treating this rare type of cancer. Pediatric oncologists, cancer surgeons, radiation oncologists, pathologists and radiologists at Cincinnati Children’s work together to develop comprehensive treatment plans for each patient. The entire sarcoma team monitors the progress of each patient and adjusts the therapy plan as needed.
People who are treated for soft tissue sarcoma will need regular follow-up care. This can include check-ups with the oncologist, imaging tests, blood work and other measures to evaluate their health and recovery.