Soft Tissue Cancer (Sarcoma)
A soft tissue sarcoma is a cancer that begins in the muscle, fat, fibrous tissue, nerves, blood vessels, lymph vessels, tissues around joints, deep skin tissue or other supporting tissue in the body.
Sarcomas form when the cells in the soft tissues of the body begin growing abnormally and don’t die off.
Although there are about 50 different types of sarcomas, they are not common tumors.
Common Soft Tissue Sarcomas
In adults, the most common types of sarcomas are
- Malignant Fibrous Histiocytomas (Fibrous Tissue) (MFHs)
- Liposarcomas (Fat Tissue)
- Leiomyosarcomas (Smooth Muscle)
Certain types are more common in certain areas of the body than others. For example, malignant fibrous histiocytomas and liposarcomas are more common in the legs, while leiomyosarcomas are more common in the abdomen.
Uncertain Tissue Type Tumors
Some sarcomas are more challenging to classify. In these cases, doctors will look at the tumor tissue under a microscope and perform other tests.
Although they can usually classify most sarcomas, doctors have not been able to determine the link between all sarcomas and the soft tissue from which they originated.
Malignant Fibrous Histiocytomas (Fibrous Tissue) (MFHs) or Pleomorphic Undifferentiated Sarcomas
MFHs are formed from fibrous tissue, Although the exact tissue type of MFHs is uncertain, they are formed from fibrous tissue, which is found in tendons, in ligaments and in the covering on bones as well as other body organs.
Malignant fibrous histiocytomas are most often found in the arms or legs, although they can start inside the back of the abdomen. Tending to grow locally, MFHs can spread to distant sites if not treated.
Fat Tissue Tumors
These malignant tumors form in fat tissue and can develop anywhere in the body. Liposarcomas most often develop in the thigh, behind the knee and inside the back of the abdomen.
Muscle Tissue Tumors
Muscle tissue tumors form in two types of muscle tissue: smooth and skeletal.
Smooth muscle is found in internal organs such as the stomach, intestines, blood vessels or uterus (womb). It causes these organs to contract involuntarily, which means we don’t control the muscle movement.
- Leiomyosarcomas: These malignant tumors of smooth muscle can grow almost anywhere in the body, but they are most often found in the retroperitoneum (area in back of the abdominal cavity), the internal organs and blood vessels.
Skeletal muscle (striated muscle) lets us move our arms, legs and other body parts when we want to move them, which is called voluntary movement.