What is soft tissue sarcoma?
Soft tissue sarcoma is a type of cancer that forms in the soft tissues of the body. Cancer starts when cells begin to grow out of control.
Soft tissue refers to all the supporting tissues in the body, apart from the bones. They include fat, muscle, nerves, tendons, deep skin tissue, lymph vessels, blood vessels and tissue around joints. A soft tissue sarcoma is a rare type of cancer that generally forms as a painless lump (tumour) in any one of these soft tissues. It can develop anywhere in the body, but most commonly in the thigh, shoulder, arm, pelvis and abdomen.
There are more than 70 types of soft tissue sarcoma. The most common type in adults is undifferentiated pleomorphic sarcoma (UPS), which is made u p of many abnormal spindle-shaped cells.
Soft tissue sarcoma is rare. It is estimated that 2035 new cases will be diagnosed in Australia in 2021. It is more likely to be found in people over 55 years of age.
Soft tissue sarcoma symptoms
Soft tissue sarcoma usually doesn’t cause symptoms in its early stages. A painless lump may develop over a period of months as the cancer grows. You may develop pain as the lump grows and presses on muscles and nerves. Other symptoms may develop depending on where in the body the sarcoma is.
Causes of soft tissue sarcoma
The causes of most sarcomas are not known. However, there are several risk factors:
Radiation therapy – there is a very small risk for people who have had radiation therapy to treat other types of cancer
Genetic factors – some rare, inherited conditions can increase the risk of being diagnosed with soft tissue sarcoma.
Chemicals – some sarcomas may be linked to being exposed to chemicals including vinyl chloride (used to make plastic) and some high-dose herbicides (weedkillers).
Other – long-term lymphoedema in the body, for example in the legs or arms (swelling from a build-up of lymph fluid) has been linked with angiosarcoma.
Diagnosis of soft tissue sarcoma
If your doctor thinks that you may have a soft tissue sarcoma, they will take your medical history, perform a physical examination (including feeling any lumps) and carry out certain tests.
If the results suggest that you may have sarcoma, your doctor will refer you to a specialist who will carry out more tests. These may include:
This will include a full blood count to measure your white blood cells, red blood cells and platelets.
This is a painless scan of your chest to check your lungs for signs of cancer.
Special machines are used to scan and create pictures of the inside of your body. You may have an injection of dye into your veins before the scan which makes the pictures clearer. During the scan you will lie on a table which moves in and out of the scanner. A CT scan takes about 10-30 minutes.
An MRI scan produces detailed cross-sectional pictures of your body and can show the extent of any tumours. You will lie on a table which slides into a large metal tube that is open at both ends. An MRI scan takes about 30-90 minutes.
Before having the PET scan you will be injected with a small amount of radioactive solutions. You will be asked to sit for 30-90 minutes so the solution can mover around your body. Many cancer cells will show up brighter on the scan. The scan takes around 30 minutes.
A biopsy is the removal of some tissue from the affected area for examination under a microscope. A biopsy is the only sure way to diagnose a soft tissue sarcoma.
Treatment for soft tissue sarcoma
Discussion with your doctor will help you decide on the best treatment for your sarcoma depending on the type of sarcoma you have; where it is in your body; whether or not the cancer has spread; your age, fitness and general health and your preferences.
The main treatments include surgery, chemotherapy and radiation therapy. These can be given alone or in combination. This is called multi-modality treatment.
Surgery is the main treatment for most types of soft tissue sarcoma. Surgery usually involves removing the cancer and some healthy tissue around the cancer. This is called a wide local excision.
The type of operation you have will depend on where the sarcoma is. Most sarcomas are found in the arm or leg. This usually means having limb-sparing surgery. Amputation is less common with soft tissue sarcoma. If the sarcoma is in another part of the body, for example the chest or abdomen, surgery will depend on where the cancer is and how big it is. Your surgeon will discuss the type of operation you may need.
Radiation therapy (radiotherapy)
Radiation therapy (also known as radiotherapy) uses high energy rays to destroy cancer cells. Sarcoma is known to be very sensitive to radiation therapy. It may be used:
- before surgery, to destroy the cancer cells and create a ‘rind’ around the cancer, which helps the surgeon to perform good surgery
- f the cancer is too big to remove with surgery
- if the cancer has spread to other parts of the body
- after surgery, to destroy any remaining cancer cells and stop the cancer coming back
- if the cancer is in a place in the body that is too hard to reach using surgery.
Chemotherapy is the use of drugs to kill or slow the growth of cancer cells. You may have one chemotherapy drug, or a combination of drugs. Your treatment will depend on your situation and the type of sarcoma you have. It may also be used to help stop a sarcoma coming back after surgery. Your medical oncologist will discuss options with you.
Targeted therapy is a cancer treatment that uses drugs to target specific genes and proteins that are involved in the growth and survival of cancer cells.
The drugs used in targeted therapy work in a different way to chemotherapy drugs. While chemotherapy affects all rapidly dividing cells and works by killing cancerous cells (cytotoxic), targeted therapy attacks specific molecules within cells and often works by blocking cell growth (cytostatic).
In some cases of soft tissue sarcoma, your medical team may talk to you about palliative care. Palliative care aims to improve your quality of life by alleviating symptoms of cancer without trying to cure the disease.
As well as slowing the spread of soft tissue sarcoma, palliative treatment can relieve pain and help manage other symptoms. Treatment may include radiotherapy, chemotherapy or other drug therapies.
Treatment TeamDepending on your treatment, your treatment team may consist of a number of different health professionals, such as:
- GP (General Practitioner)- looks after your general health and works with your specialists to coordinate treatment.
- Radiation oncologist- prescribes and coordinates radiation therapy treatment.
- Medical oncologist- prescribes and coordinates the course of chemotherapy.
- Paediatric oncologist - <br>
- Cancer nurses- assist with treatment and provide information and support throughout your treatment.
- Physiotherapist/occupational therapist- help with physical and practical problems such as restoring movement and mobility after treatment.
- Dietitian- recommends an eating plan to follow while you are in treatment and recovery.
- Other allied health professionals- such as social workers, pharmacists and counsellors..
Screening for soft tissue sarcoma
There is currently no national screening program for soft tissue sarcoma available in Australia.
Preventing soft tissue sarcoma
As the causes of most soft tissue sarcomas are not known there is no specific prevention. However, avoiding exposure to certain chemicals such as vinyl chloride or some high-dose herbicides, may reduce your risk.
Prognosis of soft tissue sarcoma
It is not possible for a doctor to predict the exact course of a disease, as it will depend on each person's individual circumstances. However, your doctor may give you a prognosis, the likely outcome of the disease, based on the type of breast cancer you have, the test results, the rate of tumour growth, as well as your age, fitness and medical history.
Understanding Soft Tissue Sarcoma. Cancer Council Australia ©2021. Last medical review of the source fact sheet: February 2021.
Australian Institute of Health and Welfare (AIHW), Australian Cancer Incidence and Mortality (ACIM) books: Soft tissue sarcomas, AIHW, Canberra, 2018.
This web-based resource was made possible by the Cancer Australia Supporting people with cancer Grant initiative, funded by the Australian Government.