What is osteosarcoma?

Osteosarcoma is a type of bone cancer that begins in the cells that form bones. Osteosarcoma is most often found in the long bones — more often the legs, but sometimes the arms — but it can start in any bone. In very rare instances, it occurs in soft tissue outside the bone.

What chemotherapy is used to treat osteosarcoma?

Chemotherapy is also sometimes used after surgery. In this case, the aim is to kill off any local cancer cells which remain in the area of the tumour. The main types of chemotherapy used to treat osteosarcoma are doxorubicin, cisplatin, high-dose methotrexate and ifosfamide.

What is extraskeletal osteosarcoma?

Extraskeletal osteosarcoma is a very infrequently diagnosed soft-tissue sarcoma subtype which has identical histological features to bone osteosarcoma. However, its demographics, presentation, radiology and treatment strategy differ from those of osteosarcoma.

Is periosteal osteosarcoma visible on radiographs?

Periosteal osteosarcoma (PIOS) has a matrix component that is mainly cartilaginous and less common than parosteal. PIOS tends to arise between the cortex and the cambium layer of the periosteum, and therefore a periosteal reaction is usually visible on radiographs [33].

What are the genetics of osteosarcoma?

The genetic factors that contribute to the development of osteosarcomas are heterogeneous; this means that there are different genetic abnormalities or mechanisms that result in susceptibility to disease. Although mutations in genes like RB1 or p53 lead to a higher risk of osteosarcoma, most affected individuals do not have changes in these genes.

What are the histologic subtypes of osteosarcomas?

Conventional osteosarcomas can be further divided by histological subtype: Osteosarcomas are bulky tumors where a heterogeneous cut surface demonstrates areas of hemorrhage, fibrosis, and cystic degeneration. Their extension within the medullary cavity is often much more extensive than the bulky part of the tumor would suggest.

Is osteosarcoma a heterogeneous disease?

A variation in the WWOX gene is also seen in increased frequency in individuals with osteosarcoma. The genetic factors that contribute to the development of osteosarcomas are heterogeneous; this means that there are different genetic abnormalities or mechanisms that result in susceptibility to disease.