Sarcomas are a group of rare cancers that begin in the bones and connective tissue such as muscles and fatty tissue. These cancers consist of more than 70 types. However, in this article we will discuss soft tissue sarcoma which begins in the soft tissue (connective tissue).
Soft tissue sarcoma starts in the tissues that connect, support and surround body structures. Soft tissue tumours consist of several types but not all of them are cancerous. However, when the word sarcoma is associated with a soft tissue tumour then it means it the tumour is malignant (cancerous). When a soft tissue tumour has both cancer and non-cancer properties, it known as an intermediate soft tissue tumour.
Causes of Soft Tissue Sarcoma
Just as is the case in most cancers, the clear cause of soft tissue sarcoma is unknown. Cancer occurs as a result of mutations in the DNA which lead to the rapid and uncontrollable growth of cells which can cause the formation of a tumour.
What determines the type of soft tissue sarcoma one develops is the type of cell affected. Types of soft tissue sarcomas include epithelioid sarcoma, Kaposi sarcoma, angiosarcoma and liposarcoma, among others.
Even though the exact cause of soft tissue sarcoma is unknown, there are certain factors that increase its risk, and these include:
- Radiation exposure: People who have previously had radiation therapy for other cancers are at an increased risk of developing sarcoma than people who have not.
- Inherited genetic syndromes: Certain inherited diseases such as neurofibromatosis, retinoblastoma and tuberous sclerosis increase the risk of developing soft tissue sarcoma.
- Exposure to chemicals: Being exposed to chemicals such as arsenic and herbicides can increase soft tissue sarcoma risk.
- Immune System abnormalities: Certain conditions such as HIV, cancers like leukaemia, and other autoimmune conditions like lupus weaken the immune system making it difficult to fight infections, thereby, increasing the risk of other conditions, in this case soft tissue sarcoma.
- Lymphedema: With damage to lymph nodes lymph fluid can build up and cause swelling, which is referred to as lymphedema. People who have lymph nodes removed have a risk of developing soft tissue sarcoma in the same areas.
Symptoms caused by Soft Tissue Sarcomas
In the early stages, soft tissue sarcomas may not cause any symptoms but as the disease progresses a person may experience:
- A new lump or one that is continuing to grow
- Blood in the stool
- Vomiting blood
- Abdominal pain that gets worse
- Limited mobility which occurs if the lump is pressing against a nerve or muscle
- Skin lesion when the lump breaks through the skin
If you experience any of these symptoms, see a doctor even though having these symptoms does not necessarily mean that you have cancer.
How is Soft Tissue Sarcoma Diagnosed?
After finding out what symptoms you have, examining you and reviewing your medical history, tests can be done to determine whether you have soft tissue sarcoma. These tests include:
- Imaging tests: These could be x-rays, ultrasound, computerised tomography (CT) scan or other more advanced imaging tests like magnetic resonance imaging (MRI) and positron emission tomography (PET) scan to give images of the inside of the body, particularly where the cancer is suspected to be.
- Biopsy: It involves taking a tissue sample with a needle or through a minor surgery, from the growth or tumour and examining the sample under a microscope to determine whether it is cancerous or not.
- Molecular testing: Laboratory tests are done on a tissue sample to check for specific proteins, genes and other factors that are unique to the tumour which helps in deciding on the treatment to use.
Treating Soft Tissue Sarcomas
Treatment depends on the type of soft tissue sarcoma, where it is located as well as its stage. It is advisable to discuss with your doctor or specialist the best option and your preference. Treatment options include:
- Surgery: This is usually the first option in most cases, after which additional treatment can be given, if necessary.
- Chemotherapy: It involves administering anti-cancer drugs to destroy cancer cells or stop their growth and spread. This treatment can be used together with other treatments like radiotherapy and surgery.
- Radiotherapy: This treatment uses high energy beams to kill cancer cells and in most cases this treatment is given after surgery in which case it is known as adjuvant treatment (to kill remaining cancer cells after surgery). When radiotherapy is done before surgery, it is known as neoadjuvant treatment (to shrink a tumour and make it easier to remove surgically).
- Targeted therapy: This treatment is a type of chemotherapy that is used to target specific proteins and genes that provide a conducive environment for cancer to grow and spread, by blocking the action of protein in kinases cells preventing the growth and spread of cancer cells.
- Immunotherapy: Also known as biological therapy, this treatment option is designed to boost the body’s immunity, making it aware of the presence of cancer cells in the body and enabling it to fight them.
Can you prevent Soft Tissue Sarcomas?
There is no exact way to prevent this cancer; however, you can reduce your risk of these cancers by:
- Avoiding radiation exposure,
- Avoiding exposure to harmful chemical like arsenic which increase sarcoma risk,
- Preventing yourself from contracting infections like HIV that weaken the immune system and make you vulnerable to diseases like cancer, and
- Getting tested regularly if you are at a high risk of developing this cancer, especially due to genetic syndromes like neurofibromatosis.