Master Ewing's Sarcoma with Picmonic for Medicine

Ewing's sarcoma is most common in boys less than 15 years of age, and is the second most common bone sarcoma in children.

There is a translocation of the EWS gene on chromosome 22 and the ETS transcription factor on chromosome 11, which causes abnormal cell proliferation and survival.

Ewing's sarcoma tends to affect the long bones, as well as the flat bones of the pelvis, scapula and the ribs.

Ewing's sarcoma tends to present in the long shaft of the bone, known as the diaphysis.

Ewing's sarcoma histologically appears as sheets of small blue cells that are slightly larger than lymphocytes and contain little cytoplasm.

Ewing's sarcoma is a malignant tumor that often metastasizes hematogenously to the lungs, bone marrow and other bones.

Ewing's sarcoma is an aggressive tumor that can invade beyond the bone into the soft tissue.

Radiographically, the tumor has an onion- skin appearance, and is observed as a periosteal reaction. A periosteal reaction is the formation of new bone in response to injury, or other stimuli of the periosteum surrounding the bone. This occurs because the body treats this tumor as a permeative lytic lesion. This characteristic onion-skinning is from reactive bone formation in a lamellated, concentric pattern.

Ewing's sarcoma responds very well to chemotherapy with or without surgical resection.