Diagnosis & staging
Diagnosis
These are tests that may used to diagnose this type of cancer.
- Physical examination.
- A chest x-ray is used to determine if the cancer has spread to the lungs.
- A computerized tomography scan (CT Scan) produces a three dimensional image of the tumour and screens for spread to the lungs if the chest X-ray was normal.
- A magnetic resonance imaging scan (MRI) produces detailed images of the tumour.
- A biopsy requires the removal of a small amount of tissue for examination under a microscope to determine if the tumour is cancerous. Biopsy should be approached with caution, and a surgical oncologist must be consulted.
- A routine bone scan is done for patients with rhabdomyosarcoma or soft tissue variants of Ewing's/ peripheral neuroectodermal tumour (PNET).
For more information on tests used to diagnose cancer, see our Recommended Websites, Diagnostic Tests section.
Types and Stages
Types of Soft Tissue Sarcomas
The tumours are divided into groups named for the tissue type that the sarcoma cells most closely mimic.
Fibrosarcomas
- Fibrosarcomas often occur around scars, muscles, nerves, tendons and around the lining of the bone.
- The cancer can spread through the bloodstream to the lungs.
- It is most frequent in older adults.
Liposarcomas
- These tumours develop in the fat tissue of the thigh, groin, buttocks area, or abdomen.
- These tumours may be large but their large size does not necessarily mean that they are fast-growing.
- They are different from and do not arise from lipomas (non-cancerous fatty tumours).
- Liposarcomas are most common in older adults.
- A very aggressive round cell variant may be treated with adjuvant chemotherapy along with surgery and radiation.
Rhabdomyosarcomas
- Rhabdomyosarcoma is the most common soft tissue sarcoma of childhood. It generally affects children between the ages of two and six.
- Rhabdomyosarcomas can spread quickly through the bloodstream to distant parts of the body.
- Rhabdomyosarcomas are divided into subtypes:
- Embryonal – occurs in the head, neck and eye
- Embryonal botryoid – occurs in the genito-urinary tract
- Alveolar – occurs in the muscles of arms and legs
- Adult pleomorphic or anaplastic - occurs in older kids and adult patients, usually in the muscles of arms and legs.
- Treatment includes surgery, radiation and chemotherapy.
Leiomyosarcomas
- Leiomyosarcomas are tumours of the smooth muscle that commonly arise in the uterus or in blood vessels.
Angiosarcomas and Lymphangiosarcomas
- Angiosarcomas arise in vascular tissue and Lymphangiosarcomas arise in the lymphatic system.
- These cancer cells easily spread into the bloodstream.
- Lymphangiosarcoma may be seen in patients with chronic lymphedema.
Synovial Cell Sarcomas
- Synovial Cell Sarcoma usually occurs in tissue next to the joints, especially in the knee, ankle and hand.
- These tumours, as with other soft tissue sarcomas, can occur anywhere in the body, even in the heart.
- Occasionally they may spread to the skin, notably the scalp.
- Spread to the lymph nodes is uncommon.
Malignant Peripheral Nerve Sheath tumour (MPNST) (previously called Neurofibrosarcoma)
- MPNST develops in the cells that surround a nerve.
- It may arise in patients with neurofibromatosis (a genetic disorder of the nervous system that effects the development of nerve cell tissues).
- As the tumour grows it may cause pain or dysfunction.
Malignant Fibrous Histiocytoma (MFH)
- Malignant Fibrous Histiocytoma is a term that describes a high grade soft tissue tumour that does not look like any specific subtype of sarcoma.
- It can be found anywhere in the body.
- In superficial sites such as the skin, it may behave like a non-cancerous tumour despite fast growing cells, but must be adequately removed with a cancer-type surgery.
- When MFH occurs deep within body cavities or muscles it may be very fast growing.
Gastrointestinal Stromal Tumour (GIST)
- GIST is one of the most common types of sarcoma with approximately 50 cases per year in BC.
- Patients may have symptoms such as a lump in their abdomen or very low red blood cells counts (anemia).
- Sometimes GISTs may be discovered when a patient is having a scan or operation for a different reason.
- Gastrointestinal Stromal Tumours were previously called leiomyosarcoma of the gastrointestinal tract, but they are now believed to be related to the cells which control normal bowel contractions.
- GIST may arise anywhere within the abdomen, but most commonly from the stomach and small bowel.
- The cells behave like normal cells and grow at a slow rate. However, it may be very hard to prevent recurrence even if the tumour has been surgically removed.
- Spreads to liver first rather than to the lungs.
- Drug treatment may be used for patients with high risk tumours and for patients who have had spread of the cancer to other sites.
Kaposi's Sarcoma
- Kaposi Sarcoma (KS) is an uncommon cancer that occurs in a classic slow-growing form and also in an AIDS-related form.
- Classic KS usually occurs in older people, usually over 70 years old, of Russian-Jewish, Italian and African origin.
- KS that is AIDS-related occurs in people who are infected with the human immunodeficiency virus (HIV) or who have developed acquired immunodeficiency syndrome (AIDS). The skin lesions of people with KS contain human herpesvirus-8 (HHV-8), also known as Kaposi sarcoma herpesvirus (KSHV). Not everyone infected with HHV-8 gets KS.
- People with HHV-8 who are most at risk include those with weakened immune systems as a result of disease, drugs, or an organ transplant.
- Men are affected over twice as much as women.
Stages
Staging describes the extent of a cancer. The TNM classification system is used as the standard around the world. In general a lower number in each category means a better prognosis. The stage of the cancer is used to plan the treatment.
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G (Grade) describes how the tumour cells look under the microscope
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T describes the site and size of the main tumour (primary)
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N describes involvement of lymph nodes
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M relates to whether the cancer has spread (presence or absence of distant metastases)
