Osteosarcoma

Osteosarcoma is the most common malignant bone tumor. It arises from primitive bone-forming cells, and histologic trademark is the production of malignant osteoid. May be present and other cell populations derived from pluripotent mesenchymal cells.Osteosarcoma is a deadly form of cancer that causes death of musculoskeletal disease patients with lung metastases. Most are solitary osteosarcoma and grow in areas with rapid growth of long bones in children. Areas most affected are the distal femur, proximal tibia and proximal humerus, but virtually any bone can be affected. Not all are solitary osteosarcoma, and after a period of six months of evolution several regions of the body may be affected bone-synchronous osteosarcoma. This type of osteosarcoma is rare, but when there affects children under 10.
Symptoms are present a few months before the patient is diagnosed. Pain symptom onset, especially exaggerated in the activity. Patients may be worried about arthritis. Often there is a history of trauma, but still vague role in pathogenesis. Fractures are not common pathological condition. Clinic patient may or may not accuse local swelling depending on the size and location of the tumor. Tumor that has spread to lungs and respiratory distress rarely shows such indicating extreme damage lungs. Metastases are rare elsewhere.
Chemotherapy is critical for patients with osteosarcoma. This not only facilitates tumor reduction but decreases the risk of metastasis. Patients who had a good histologic response to chemotherapy, destroyed over 90% of tumor have a better prognosis than those of coror tumors do not respond.Osteosarcoma is resistant to radiation, so it is not included in standard therapy regimens. Based therapy is surgical removal of malignant lesions. Limb preservation is most commonly used to treat these patients. Chemotherapy is also required to treat metastatic disease, which is present at diagnosis but often undetectable. Because osteosarcoma unresponsive to radiotherapy, surgery is the only option for permanent and total tumor removal. May order partial or total joint prosthesis or bone reconstruction.
Anatomy and physiology of bone:Bone is a living structure of the complex. There are several types of cells in bone:Osteoblasts form bone matrix, connective-tissue and minerals that I have bone hardness d-Osteclastele prevent excessive accumulation of bone matrix and helps to maintain bone-modeling appropriate form, and removes these minerals from bone storesAdipocyte-containing bone marrow and blood-forming cells.There are two main types of bone: the flat and long ones. Flat bones help protect the brain and organs in the chest, abdomen and pelvis. Sternum, skull and bones are flat bones. Long bones of legs and arms support. The muscles that move the limbs are attached to long bones.
Osteosarcoma - PathogenesisOsteosarcoma is a bone tumor that can occur anywhere on the bone, usually the extremities of long bones near growth plates metaphyses. The most common localizations are the femur, tibia and humerus. Other important locations include the skull, pelvis and jaw. There are a number of variants of osteosarcoma, including conventional types: osteoblasts, chondroblasts and fibroblasts, and then types teleangieactic, multifocal, and periosteal paraosteal.Osteosarcoma is a malignant mesenchymal sarcoma characterized by direct formation of bone or osteoid by tumor cells.It is subclassified according to histologic characteristics of the cells. When most cells produce osteoid tumor is called the osteoblast. When production is predominant tumor condroida matrix is ​​called chondroblasts. When cells are mostly spindle and form some use the term fibroblast matrix.
Causes and risk factors for osteosarcomaThe exact cause of osteosarcoma is unknown. The rapid growth of bone appears to be a predisposing factor for osteosarcoma, suggested the incidence of tumors in adolescence and typical location in the area adjacent metaphyses of long bone growth. The only known risk factor is external radiation exposure.Osteosarcoma is a form of radiation induced secondary. The genetic predisposition is present in patients who have personal or family history of medical diseases such as Paget disease, fibrous dysplasia, endocromatoza, and hereditary multiple exostoze retinoblastoma.