Sarcomas are rare types of cancer that develop in the supporting tissues of the body. There are two main types: Bone Sarcomas and Soft Tissue Sarcomas.
Ewing’s sarcoma is a bone cancer (although it can also very rarely develop in the soft tissue) and is the second most common primary sarcoma that can develop in children, comprising 10-15% of childhood bone cancers.
The Ewing’s family of tumours:
- Ewing’s sarcoma of bone
- Extraosseous Ewing’s – a tumour outside of the bone
- Primitive Neuroectodermal Tumour (PNET)
- Askin’s Tumour (PNET of the chest wall).
Ewing’s sarcoma occurs most commonly in the ribs, pelvis, chest, long bones of the legs and arms, skull, and vertebral column (spine). Extraosseous Ewing Sarcoma appears in the soft tissue of the arms, legs, trunk, head, neck, abdominal cavity, or other areas.
Ewing’s sarcoma is not very common in younger children; it occurs mostly in the teenage years and is slightly more prevalent in boys.
Osteosarcoma is a bone cancer which makes up about 5% of Childhood Cancers. Malignant Fibrous Histiocytoma (MFH) of the bone is a rare tumour of the bone, and is treated in the same way as osteosarcoma.
Osteosarcoma (also called osteogenic sarcoma) is the most common type of bone cancer and starts in the osteoblasts, which are the bone cells at the end of the long bones where new bone tissue forms as a young person grows.
Types of Osteosarcoma:
- Periosteal Osteosarcoma
- Parosteal sarcoma of bone
- Telangiectatic Osteogenic Sarcoma
- Small Cell Osteosarcoma
Osteosarcoma is most prevalent in teenagers, and most often forms in the bones near the knees of children and teenagers or in the bones surrounding the shoulder joints. Most osteosarcomas occur in the centre of the bone.
Rhabdomyosarcoma is a soft tissue cancer that develops in the soft tissue of striated muscles, which are the muscles that are attached to bones and help the body to move. Rhabdomyosarcoma accounts for about 50% of soft tissue sarcomas in children and can begin in various places in the body.
The 3 Main Types of Rhabdomyosarcoma:
- Embryonal: This is the most common type and occurs most often in the head and neck area, or in the urinary or genital or organs. Usually occurs in children under the age of 15
- Alveolar: This is an aggressive tumour which usually occurs during the teen years, and most often in the arms, legs, chest, abdomen, genital organs, or anal area.
- Anaplastic: This type rarely occurs in children
Rhabdomyosarcoma is mostly found in children under the age of 10 and occurs in more boys than girls. If the tumour occurs in the head or neck area it may spread to the brain or the fluid surrounding the spinal cord.