This page was reviewed under our medical and editorial policy by
Maurie Markman, MD, President, Medicine & Science
This page was updated on June 6, 2022.
Soft tissue sarcoma affects the tissues that support, connect or surround other organs and structures. The condition, therefore, often affects a wide variety of body areas, potentially making soft tissue sarcoma symptoms challenging to identify.
As with many forms of cancer, symptoms may appear at a more advanced stage of soft tissue sarcoma—or the patient may not notice any symptoms at all. If they are present, symptoms will also vary depending on the type of sarcoma and its location.
Since soft tissue sarcomas may start in any type of soft tissue—including fat, muscle, nerves and more—these cancers may grow almost anywhere in the body. However, most (60 percent) start in the arms or legs, according to the American Society of Clinical Oncology. Other common areas where a sarcoma may develop include the torso or abdomen (where 30 percent of soft tissue sarcomas occur) and the head or neck (10 percent). Soft tissue sarcomas affecting the abdomen are called retroperitoneal sarcomas.
Soft tissue sarcomas may spread, or metastasize, beyond where the cancer starts. Metastasis occurs when cancer cells travel through the bloodstream or lymph system and reach other parts of the body.
When soft tissue sarcomas metastasize, the lungs are the most common site of spread. About 83 percent of metastatic soft tissue sarcomas affect the lungs, according to a 2018 review in Pharmacy and Therapeutics. Certain types of soft tissue sarcomas may be more likely to spread to other places. Myxoid liposarcomas may spread to the pelvis or abdomen, while angiosarcomas or alveolar soft part sarcomas may spread to the brain.
Symptoms of soft tissue sarcoma include:
A lump or mass is the most common soft tissue sarcoma symptom. The lump forms in the area in which the tumor is growing, and it may be accompanied by some pain if it’s pressing on a nerve or muscle. Even if the lump isn’t painful, if it continues to grow, or if it’s located deep within an extremity or body cavity, consult a doctor. Sarcomas that grow in tissue near the skin's surface may easily move when touched, while those embedded deeper under the skin may be more fixed in place. They’re typically larger than the size of a golf ball, which is around 4 cm across. Whether or not the lump is painful is generally not considered an important factor in distinguishing a sarcoma from something else.
Uncomfortable swelling, especially when it’s located in the arms and leg, may be a sign of soft tissue sarcoma.
Limited mobility may result from a tumor that restricts motion (such as those found in the hips, knees, shoulders or hands).
Skin lesions may occur when a sarcoma tumor breaks through the skin.
Because a sarcoma tumor may form almost anywhere in the body, symptoms may vary. For example, sarcomas in the abdomen may cause abdominal pain, vomiting or constipation, while sarcomas in the uterus may cause vaginal bleeding and/or abdominal pain. With gastrointestinal stromal tumors (GISTs), the patient may feel full after eating very small meals, or you may vomit blood or have dark bowel movements. Sarcomas that begin in the lungs or heart may lead to symptoms such as chest pain and breathing problems.
Signs that should lead the patient to see a doctor immediately include:
Soft-tissue sarcoma may be difficult to spot, and many of the symptoms associated with this cancer are often caused by something more common than a sarcoma. However, patients who are experiencing symptoms associated with this cancer should visit a doctor to find out the cause.
To diagnose a soft tissue sarcoma, a doctor may start by conducting a physical exam to feel for lumps suspected to be a sarcoma. Imaging tests may be the next step, such as an X-ray or ultrasound, to take a deeper look at potential areas of cancer in the body. More detailed scans, such as a computed tomography (CT) scan or magnetic resonance imaging (MRI), may also be used.
Imaging tests help indicate whether the patient has a sarcoma, but a biopsy is typically needed to confirm the diagnosis and determine the type of sarcoma.
According to the American Cancer Society, there are more than 50 distinct soft tissue sarcoma types, so it’s important to see a doctor who is knowledgeable about sarcomas.