What is Cancer
Cancer Type

Soft Tissue cancer

What is soft tissue sarcoma?
Soft tissue is the name for all the supporting tissues in the body, apart from the bones. They include fat, muscle, nerves, deep skin tissue, blood vessels and the tissue that surrounds joints (synovial tissue). These tissues support and connect all the organs and structures of the body. They are known as connective tissue. A soft tissue sarcoma is a rare type of cancer that forms as a painless lump (tumour) in any one of these soft tissues. They most commonly develop in the thigh, shoulder and pelvis. Sometimes they can grow in the abdomen or chest (trunk).
Types of soft tissue sarcoma
There are over 70 types. They are named after the abnormal cells that make up the sarcoma. The most common type is malignant fibrous histiocytoma (MFH), which is made up of many abnormal spindle-shaped cells. Liposarcoma is the next most common type of soft tissue sarcoma. It is made up of many abnormal fat cells.
 
Other types of soft tissue sarcoma include:
  • leiomyosarcoma and rhabdomyosarcoma, from muscle tissues
  • angiosarcoma, from blood vessels
  • ewing sarcoma and primitive neuroectodermal tumour (PNET)
  • malignant peripheral nerve sheath tumour (MPNST or PNST)
  • gastrointestinal stromal sarcoma (GIST) (this is treated differently from other types of soft tissue sarcoma)
  • stromal sarcoma from supporting tissues
  • kaposi sarcoma of the skin
  • synovial sarcoma.
How common is it?
Soft tissue sarcoma is not common. The National Cancer Registry (2007) reports 7 registered cases of malignant fibrous histiocytoma in Malaysia.
 
Soft tissue sarcoma can develop at any age. Although it's more likely to happen in people over the age of 55, young adults may also be affected. There's almost an equal risk for males and females.
Causes
The causes of most sarcomas are not known. However, there are several risk factors. 
  1. Radiotherapy
    There is a very small risk for people who have had radiotherapy. The risk is higher for people who had high doses of radiotherapy at a very young age. Most people who have had radiotherapy in the past will not develop a sarcoma.
  2. Genetic factors
    Some rare, inherited conditions can put people at more risk of soft tissue sarcoma. These are:
    • Von Recklinghausen disease (neurofibromatosis): non-cancerous lumps that develop in the nerves under the skin and over time can turn into sarcoma
    • Li–Fraumeni syndrome: a genetic condition that increases the risk of many cancers in one family, including soft tissue sarcoma
    • Retinoblastoma: a rare type of eye cancer mainly found in children. Most people know if one of these very rare conditions runs in their family, and if so, that they may pass it to their children. A small number of people develop sarcoma due to genetic changes that happen during their lifetime, rather than inheriting a faulty gene.
Symptoms
Sarcoma usually doesn’t cause symptoms in its early stages. As it grows over a period of months, you may develop a painless lump. You may begin to have pain as the lump grows and presses on nerves and muscles. Other symptoms will depend on where in the body the sarcoma is. Sometimes a soft tissue sarcoma may be mistaken for a benign fatty lump (lipoma) or bruise (haematoma). This can delay tests that would help make the right diagnosis. Most people who develop a painless lump do not have a sarcoma. It is much more likely to be a less serious condition. However, if you have symptoms for more than two weeks, you should see your doctor.
Diagnosis
If your doctor thinks that you may have a soft tissue sarcoma, they will carry out blood tests, x-rays and scans. These tests are needed to rule out other conditions. If the results suggest that you may have sarcoma, your doctor will refer you to a specialist centre.
 
You may need to have a biopsy. This is the only sure way to diagnose a soft tissue sarcoma. A biopsy means taking a sample of cells from the lump and examining them under a microscope. Your doctor will use a fine needle to do this. You will have local anaesthetic to numb the area before the needle is put into the lump. A tissue biopsy should only be carried out by a specialist who does them regularly and has special expertise in this area. It is important that the biopsy is done properly, to reduce the chance of the cancer spreading. It could also affect the type of treatment that you may be able to have.
Treatment
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 (its stage)
  • your age, fitness and general health
  • what you want.  
Treatment may include surgery, chemotherapy and radiotherapy. They can be given alone or in combination.
 
Surgery
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. Doctors call this a wide local excision. The healthy tissue is removed to help reduce the risk of the cancer coming back in that area. The type of operation depends on where the sarcoma is. Most sarcomas are in the arm or leg. This usually means having limb-sparing surgery; amputation is less common. But sarcoma can develop in other parts of the body, for example the chest or abdomen. Surgery to these areas will depend on where the cancer is and how big it is. Your surgeon will discuss the type of operation you may need.
 
The most important thing is that you have your surgery done by an experienced surgeon working in a specialist centre for sarcoma. Plastic surgeons are sometimes asked to work with surgeons to help restore parts of the body affected by surgery. This would be part of your main operation. The type of surgery you have will depend on where the sarcoma is and how much tissue needs to be removed. Before you make any decision about treatment, your surgeon will discuss all your options.
 
Limb-sparing surgery
This means taking out the cancer and a margin of healthy tissue while still keeping your limb. If necessary, bones may be rebuilt using a metal implant (prosthesis) or a bone graft. A graft means taking a piece of healthy bone from somewhere else in your body, or from a ‘bone bank’. Any other gaps in the tissue are usually reconstructed using plastic surgery.
 
After surgery, a physiotherapist will help you plan an exercise program so you can get strength and function back in your limb. There will be some changes in the way the limb looks, feels or functions. The aim is for your limb to be as normal as possible.
 
This complex surgery needs to be done by a surgeon with a lot of experience in treating sarcoma. This may mean that you have to travel to a treatment centre that has a team of experts. Surgery done well may decrease the risk of the cancer cells spreading to nearby areas or other parts of the body.
 
Amputation
Sometimes it is not possible to remove all of the cancer without badly affecting the arm or leg. The doctor may advise that the only effective treatment will be to remove the limb (amputation). Amputation can be very distressing emotionally and physically. Most people will need a lot of support at this time.
 
Amputation is likely to have a huge effect on you and the people who share your life. After surgery you will have a carefully planned rehabilitation program. This will include seeing a specialist who makes false (prosthetic) limbs. A physiotherapist will help you become as independent and mobile as possible. It can take time to recover from major surgery. You may be hoping that your life will return to normal as soon as possible. However, you may need to allow yourself time to create a ‘new normal’ after losing a limb. Try not to expect too much all at once. Accept support from those close to you as much as possible.
 
Other types of support are also useful. You may find it helps to speak with a social worker or counsellor, or the Helpline may be able to put you in contact with someone else who has had the same operation. They may be able to offer advice on ways to cope and what to expect.