User:Mr. Ibrahem/Osteosarcoma

Osteosarcoma (OS) is a type of bone cancer of the osteogenic type. The most common initial symptom is bone pain, which often gets worse with exercise. In children more than half of cases occur in the long bones around the knee. Spread of the cancer often occurs. Other complications may include a pathologic fracture.

The cause is often unclear. Some cases occur secondary to Paget disease of bone, electrical burns, trauma, exposure to beryllium, alkylating agents, osteochondromatosis, enchondromatosis, fibrous dysplasia, prosthetics, or bone infections. A number of genetic syndrome increase the risk including Li-Fraumeni syndrome, Bloom syndrome, or Werner syndrome. It starts from primitive bone-forming mesenchymal cells. Diagnosis is by biopsy.

Treatment may include surgery, chemotherapy, and radiation therapy. Ongoing follow up is required to look for re-occurrence. The 5-year survival rate in those under 15 is about 76%. Outcomes are worse in adults.

About 4.4 cases per million per year occur in those under the age of 25. It is most common in those 10 to 14 years old and those over the age of 65. It represents about 5% of cancer in children and about 20% of tumors that start within bone. The term "osteosarcoma" was introduced in 1805 by Alexis Boyer.