| • Science | • People | • Locations | • Timeline |
| Contents | ||
|
Ewing's Sarcoma is the result of a translocation between chromosomes 11 and 22, which fuses the EWS gene of chromosome 22 to the FLI1 gene of chromosome 11.
Ewing's sarcoma usually presents in childhood or early adulthood, with a peak between 10 and 20 years of age, although it can occur in younger children and older adults. It can occur anywhere in the body, but most commonly in the pelvis and proximal long tubular bones. The metaphysis and diaphysis of the femur are the most common sites, followed by the tibia and the humerus. Thirty percent are overtly metastatic at presentation.
The most common clinical findings are pain and swelling.
On conventional radiographsRadiography is the creation of radiographs, photographs made by exposing a photographic film or other image receptor to X-rays. Since X-rays penetrate solid objects, but are attenuated by them in a way that depends on the density of the objects, the pictu, the most common osseous presentation is a permeative lytic lesion with periostealPeriosteum is the connective tissue surrounding bone. As opposed to bone itself, it has nosiceptive nerve endings, making it very sensitive to manipulation. reaction. The classic description of lamellated or "onion skin" type periostealPeriosteum is the connective tissue surrounding bone. As opposed to bone itself, it has nosiceptive nerve endings, making it very sensitive to manipulation. reaction is often associated with this lesion. Plain films add valuable information in the initial evaluation or screening. The wide zone of transition (e.g. permeative) is the most useful plain film characteristic in differention of benign versus aggressive or malignant lytic lesions.
MRI should be routinely used in the work-up of malignant tumors. MRI will show the full bony and soft tissue extent and relate the tumor to other nearby anatomic structures (e.g. vessels). GadoliniumGadolinium is a chemical element in the periodic table that has the symbol Gd and atomic number 64. Notable characteristics Gadolinium is a silvery white, malleable and ductile rare earth metal with a metallic luster. It crystalizes in hexagonal, close-pa contrast is not necessary as it does not give additional information over noncontrast studies. CT can also be used to define the extraosseous extent of the tumor, especially in the skull, spine, ribs and pelvis. Both CT and MRI can be used to follow response to radiation and/or chemotherapy.Bone scintigraphy can also be used to follow tumor response to therapy.