Imaging evaluation of bone tumors

Musculoskeletal "don't touch" lesions: pictorial essay

“…Up to the sixth month, the most peripheral bone tends to mature, while the central zone presents an immature matrix, the so-called zonal phenomenon, which can be well characterized on imaging. Thereafter, the lesion tends to involute ( 5 , 7 ) . An MRI scan shows the various phases of the lesion (Figure 12).…”

“…Conventional X-ray and CT are both effective methods of characterizing bone formation and the zone phenomena. The radiologist plays a central role in the evaluation of myositis ossificans, given that, in a biopsy performed in the early stages, it will be indistinguishable from a sarcoma; the responsibility for making an accurate diagnosis therefore falls on the radiologist ( 5 , 7 - 9 ) .…”

“…Therefore, it is essential that the radiologist be able to differentiate lesions with malignant or aggressive potential (i.e., those that need specific management) from those that pose no immediate risk. In his classic text, Helms referred to the latter group of lesions as "don't touch" bone lesions ( 1 - 5 ) . Such bone lesions, now more commonly referred to as "don't touch" lesions, are defined by characteristic imaging features, the identification of which precludes the need for additional diagnostic tests or biopsies, thereby avoiding unnecessary interventions.…”

"Don't touch" bone lesions: how can we contribute?

“…In some challenging situations, including uncommon presentations such as a hemophilic pseudotumor, computed tomography or magnetic resonance imaging can be used in order to characterize the lesion, thus increasing the reliability and confidence in the accuracy of the diagnosis ( 3 - 6 ) .…”