Sarcoma develops from cells exposed by malignant degeneration of connective tissue, forming the skeleton. These tumors include osteosarcoma arising from the bone cells, chondrosarcoma - of cartilage cells, malignant fibrosarcoma and fibrohistiocytoma - of fibrous connective tissue cells, as well as lymphoma and Ewing’s sarcoma with bone marrow origin. These sarcoma composed of atypical cells fusiform shape with a high rate of cell division. Carkomy differ in nature of produced product, for example, osteosarcoma producing sarcomatous, or non-mineralized, bone.

The most frequent primary malignant bone tumors are the osteosarcoma. Their frequency is approximately 1:500 000, and in the U.S. each year 450-500 cases. These tumors occur in men slightly more often than women, while the average age of patients was 18 years for men and 17 for women.