Ewing's sarcoma other imaging findings


 * Assistant Editor(s)-In-Chief: Michael Maddaleni, B.S.

Radiograph
On conventional radiographs, the most common osseous presentation is a permeative lytic lesion with periosteal reaction. The classic description of lamellated or "onion skin" type periosteal reaction is often associated with this lesion.

There have been several different types of periosteal reactions observed
 * An 'onion-peel' appearance refers to a multi-layered reaction
 * A perpendicular reaction is referred to as a 'spiculae' or 'sunburst'. The sunburst is less common in Ewing's sarcoma patients. It is more common to see the onion peel appearance.
 * A triangular lifting from the bone at the site of detachment is referred to as 'Codman's triangle'

Plain film
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 differentiation of benign versus aggressive or malignant lytic lesions.

Scintigraphy
Bone scintigraphy can also be used to follow tumor response to therapy.