Chondroblastic osteosarcoma as defined by WHO is a histological entity characterized by predominant presence of chondroid matrix, which tends to exhibit a high degree of hyaline cartilage and is intimately associated with the nonchondroid element (osteoid or bone matrix).

Is Chondroblastic osteosarcoma cancer?

1 Introduction. Chondroblastic osteosarcoma (COS) is a rare tumor, and is a common subtype of osteosarcoma with percentage of 11% to 50%. The age at diagnosis of COS appears to be variable in various studies, mainly with a peak at about twenty years old.

What is Chondroblastic?

Chondroblastic osteosarcomas (COS) are defined as high-grade bone tumours with a substantial volume of tumour tissue having a chondrosarcomatous phenotype next to osteoid-forming areas. ^2,3. Treatment of OS relies on a combination of chemotherapy and surgery; radiotherapy has a limited role.