Retroperitoneal sarcomas occur in the retroperitoneum. This is an area behind the peritoneum, the lining of the abdominal space that covers the abdominal organs. The retroperitoneum is deep in the abdomen and pelvis, behind the abdominal lining, where organs such as the major blood vessels, kidneys, pancreas and bladder are located.
Rhabdomyosarcoma develops in the skeletal or voluntary muscles of the body – the muscles we can control ourselves. It is most commonly found in the head and neck but it also occurs in the abdomen. This is a rare type of sarcoma that affects more children than adults.
Ewing’s sarcoma usually affects the bone; however, this type develops in the soft tissue around the bone. It is sometimes called extra osseous sarcoma – extra means outside, osseous means bone. They are found in the trunk, limbs and the brain.
Soft tissue sarcomas develop in supporting or connective tissue such as the muscle, nerves, tendons, blood vessels and fatty and fibrous tissues.
Synovial sarcoma develops in cells around joints and tendons. Synovial sarcoma can occur anywhere throughout the body but often near the knee. Synovial sarcoma is most commonly associated with young adults.