Ewing’s sarcoma is actually several types of sarcomas known as the Ewing’s Family of tumours. In Ireland, there are approximately 20 cases diagnosed a year, generally in children and young adults under the age of 30. It can be found in any bone, but is most common in the bones of the lower body such as the pelvis, tibia (shin), fibula (shin), and femur (thigh).
Chondrosarcoma is a cancer that develops from the cells that produce cartilage. A little less than one-third of bone sarcomas are chondrosarcomas. While the disease can affect people of any age, unlike most other forms of bone cancer, it is more common among older people than among children. Also unlike the other bone cancers chondrosarcoma is more often found in the spine and pelvis than in legs or arms.
Osteosarcoma is a cancerous bone tumour that mainly occurs in adolescents and young adults. The bones most frequently involved are the large bones of the upper arm (humerus) and the leg (femur and tibia). In children and adolescents, 80% of these tumours arise from the bones around the knee. It is slightly more common in males than females. Although osteosarcoma is a common malignant bone tumour, it is still rare with less than 30 new cases each year in Ireland.
Parosteal osteosarcoma is a slow growing (low grade) tumour that grows on the surface of the bone. It more typically occurs in adults between the ages of 20 and 40. It is most commonly found on the upper leg, behind the knee.
Like parosteal osteosarcoma, periosteal osteosarcoma is an uncommon tumour that grows on the surface of the bone, most commonly the lower leg. It is a faster growing (high grade) tumour. It occurs in a younger age group.
Multifocal sclerosing osteosarcoma is an extremely rare form of osteosarcoma. It tends to occur in children less than 10 years old.
Osteosarcoma of the jaw and skull are rare. They typically occur in patients between the ages of 20 and 40. The bones most commonly affected are the mandible (jaw bone) and the maxilla (cheek bone).
Paget’s disease is an uncommon non-cancerous condition. It usually occurs in people over the age of 60. Approximately 1 in a 100 patients with Paget’s disease develop primary bone sarcoma. The tumours usually start in the pelvis, femur or humerus.
Radiation Induced Osteosarcoma is a rare form of osteosarcoma which occurs in people who have undergone radiation therapy treatments for other cancers. The average length of time before these tumours appear is 10 years following radiation. Post-irradiation osteosarcomas are most commonly found in the spine, pelvis, hips and shoulders.
Some types of bone cancer can develop away from the bone. They are called extra-osseous and are usually found in the muscle or skin. There are three types of extra-osseous tumours. They are giant cell tumours, osteosarcomas and Ewing’s sarcoma.
More information on the different types of sarcoma may be found in the Links section.