Cancer

Cancer is a group of diseases characterized by uncontrolled growth of tissue cells in the body and the invasion by these cells into nearby tissue and migration to distant sites. Cells are the building blocks of living things.
Cancer grows out of normal cells in the body. Normal cells multiply when the body needs them, and die when the body doesn't need them. Cancer appears to occur when the growth of cells in the body is out of control and cells divide too quickly. It can also occur when cells forget how to die.
There are many different kinds of cancers. Cancer can develop in almost any organ or tissue, such as the lung, colon, breast, skin, bones, or nerve tissue.

Soft tissue sarcoma

Soft tissue sarcomas are cancerous (malignant) tumors that originate in the soft tissues of your body. Soft tissues connect, support and surround other body structures. The soft tissues include muscle, fat, blood vessels, nerves, tendons and the lining of your joints (synovial tissues). A large variety of soft tissue sarcomas can occur in these areas.
Soft tissue sarcomas aren't common. But soft tissue sarcomas are very serious, especially if diagnosed when the disease is more advanced.
Although there are various types of soft tissue sarcoma, they generally share similar characteristics, produce similar symptoms and are treated in similar ways.