Soft Tissue Sarcoma

January 22, 2026

This page was reviewed under our medical and editorial policy by Lee Cranmer, M.D., Ph.D., professor, Department of Medical Oncology & Therapeutics Research, City of Hope^® Cancer Center Duarte.

Soft tissue sarcomas are cancers that develop in the soft connective tissues in the body, such as muscles, fat, or blood vessels. Soft tissue sarcoma is the most common type of sarcoma, accounting for nearly 14,000 new cases in the United States every year. It affects children and adults of all ages.

What Is Soft Tissue Sarcoma?

Soft tissue sarcoma may affect almost any part of the body, since it forms in the body’s connective tissues. These tissues, which make up most of our bodies, include:

• Muscles and tendons
• Bones and cartilage
• Tissue around the joints
• Fat and deep skin tissue
• Blood or lymph vessels
• Nerves

While soft tissue sarcoma may develop anywhere in the body, it is most common in the torso, head and neck.

Soft Tissue Sarcoma Symptoms

People with soft tissue sarcoma may experience different symptoms, depending on what type they have and where the tumor is located. In general, some common signs include:

• A painless lump on the surface of the skin
• Pain or tenderness in a specific spot, if a tumor has grown in size
• Trouble breathing, if a tumor is in the abdomen and is large enough to press on the lungs or other organs

Some soft tissue carcinomas do not cause any symptoms or only minor symptoms until they are relatively large.

Causes and Risk Factors

Doctors and scientists do not yet know the exact causes of soft tissue sarcoma. But research has revealed some risk factors that may make it more likely someone will develop the condition.

Radiation: Exposure to radiation, usually during treatment for another cancer, may slightly increase the risk for developing soft tissue sarcoma. The most likely time to develop sarcoma is around 10 years after the initial radiation therapy treatment.

Gene mutations: Certain rare inherited gene mutations, such as those that cause neurofibromatosis, Gardner’s syndrome or Li-Fraumeni syndrome, may be linked to higher rates of soft tissue sarcoma.

Some specific risk factors are also associated with certain types of soft tissue sarcoma. For example, people who have long-standing lymphedema (a condition that causes a build-up of lymphatic fluid in the lymph nodes) are slightly more likely to develop sarcoma in the lymph nodes.

Types of Soft Tissue Sarcoma

Because soft tissue carcinoma may develop in almost any part of the body, there are many different types of the disease, including:

• Angiosarcoma, a rare form of sarcoma, which occurs in the blood vessels or lymph vessels
• Soft tissue Ewing sarcoma, predominantly found in children and teens, which develops in the tissue near or surrounding a bone
• GIST (gastrointestinal stromal) tumors, which are a rare type of soft tissue sarcoma that occurs in the digestive tract
• Kaposi sarcoma, which starts in the lining of the blood or lymph vessels and may cause lesions on the skin or the body’s organs
• Leiomyosarcoma, which develops in the smooth muscles, mostly found inside the body’s organs
• Liposarcoma, which occurs in the body’s fatty tissues, such as the belly, arms and legs, or buttocks
• Retroperitoneal sarcoma, which is found inside the body on the back of the abdomen
• Rhabdomyosarcoma, a cancer that starts in muscle tissue, and is more common among children and teens
• Synovial sarcoma, which affects muscles, ligaments or tendons, most often in the arms or legs
• Uterine sarcoma, which occurs in the soft tissue of the uterus

Diagnosis and Testing

Soft tissue sarcoma is usually diagnosed by cancer specialists using some combination of a physical examination, imaging tests and biopsy.

A physical exam: This may sometimes be able to locate and identify a tumor, if it is close to the surface of the skin. During the exam, doctors will discuss a patient’s medical history and symptoms.

Imaging tests: X-ray, magnetic resonance imaging (MRI), or computed tomography (CT) and positron emission tomography (PET) scans may be used to get a better idea of the size and location of a soft tissue sarcoma and whether the cancer has spread.

A biopsy: For this procedure, a small sample is taken from a suspected tumor and the cells are examined under a microscope to look for signs of cancer. Most often, doctors recommend a fine needle aspiration biopsy or core biopsy, which are less invasive than an open biopsy. Biopsies are the primary way that all cancers, including soft tissue sarcomas, are diagnosed.

Soft Tissue Sarcoma Stages

Staging is the process by which the extent of a cancer is determined. This then allows decisions to be made regarding appropriate treatment. For example, if cancer is identified in only one location within a patient’s body, surgery would often be considered the main treatment in an attempt to cure the patient of that cancer. In contrast, if the cancer has metastasized, it is in different parts of the body and surgery may not be useful to treat the condition. In those circumstances, other treatments, such as chemotherapy, may be the primary treatment. Determining the extent or stage of the cancer may help guide this decision-making. This is true for soft tissue sarcoma, as it is for other types of cancer.

Soft tissue sarcoma is usually staged using the TNM staging system, which takes into account:

• T, which stands for main tumor size and location
• N, which stands for cancer spreading to the lymph nodes
• M, which stands for metastasis to other parts of the body

If a sample is taken during a biopsy, the tumor may also be assessed as grade 1, 2 or 3. Whereas stage refers to the size of the tumor and whether it has spread, grade describes what the cancer cells look like. Grade 1 cancers have cells that look most similar to normal cells, while grade 3 cancers look the most abnormal.

The TNM system, combined with the grading system, results in a stage numbered 1, 2, 3 or 4. In general, higher stage and higher grade tumors are more aggressive and/or more widespread. However, different types of soft tissue sarcoma may be staged differently, depending on where the cancer is found in the body.

Soft Tissue Sarcoma Treatment

There are multiple treatment options for soft tissue sarcoma. Determining which treatment may be the most effective depends on a variety of factors, including the location and stage of the cancer and a patient’s overall health and medical history. The most common treatments for soft tissue sarcoma are listed below.

Surgery: This procedure aims to remove a tumor. This may be particularly effective for lower stage cancers that are easily accessible in the arms, legs or torso.

Radiation therapy: This treatment may be recommended before surgery to shrink a tumor and make it easier to remove surgically. It may also be an option for tumors that are in hard-to-reach locations. Radiation therapy may also be used after surgery to lower the risk that the cancer will come back.

Chemotherapy: This involves an intravenous or oral medication that kills cancer cells. It may be used before or after surgery, or in combination with radiation therapy.

Immunotherapy: This refers to a range of medications that are designed to boost a patient’s own immune system so that it more effectively attacks and destroys cancer cells.

Targeted therapy: This term refers to treatments that interrupt cancer’s ability to grow and divide.

Not every treatment option is appropriate for every subtype of soft tissue sarcoma. A patient’s multidisciplinary cancer care team may help create a personalized treatment plan based on their unique diagnosis.

Soft Tissue Sarcoma Survival Rate

Although survival rates for specific subtypes of soft tissue sarcoma differ, the overall five-year relative survival rate for people with this disease is 66%. This means that people with soft tissue sarcoma are 66% as likely to survive more than five years after their diagnosis compared to people without this cancer type.

Survival statistics are further broken down by how far the cancer has spread, as follows.

Localized soft tissue sarcoma: This means the cancer has not spread outside the primary location, and has a five-year relative survival rate of 83.1%

Regional soft tissue sarcoma: This means the cancer has spread to regional lymph nodes, and has a five-year relative survival rate of 59.7%

Distant soft tissue sarcoma: This means the cancer has spread to locations farther away from the primary site, and has a five-year relative survival rate of 16.8%