Age / Sex : 17 / M

Adamantinoma

Discussion

Findings:

 Multilobulated, elongated shaped, eccentrically located, cortical based bone lesion with intramedullary extension along the right tibial diaphysis.

Associated localized cortical breakthrough with extraosseous extension of the lesion.

Satellite lesion at the lateral aspect of distal tibial metaphysis and medial aspect of distal fibular diaphysis and metaphysis

Differential Diagnosis:

 Osteofibrous dysplasia

Diagnosis: 

Adamantinoma
 

Discussion:

Primary low-grade, malignant bone tumor

Rare tumor (only 0.1-0.5% of all primary bone tumors)

Median age: 25-35 years (2-86 years)

Predominantly located in mid-portion of tibia and sometimes simultaneously in tibia and adjacent fibula or in fibula without tibial lesion

Locally aggressive tumor and extremely slow growing with potential to metastasize.

[Radiologic findings]

Central or eccentric, multilocular slightly expansile, sharply or poorly delineated ostelytic lesion.

Diaphyseal location, may metaphyseal extension

Well-circumscribed lesion involving anterior tibial cortex, with septations and peripheral sclerosis

Soap-bubble appearance

Commonly intra-cortical, may destroy cortex and invade extracortical soft tissues

Difficult to distinguish from osteofibrous dysplasia, which located in cortex without involvement of medullary bone and without soft tissue involvement
 

References: 

1.     Bethapudi S, Ritchie D.A., Macduff E, Straiton J. Imaging in osteofibrous dysplasia, osteofibrous dysplasia-like adamantinoma, and classic adamantinoma. Clin Radiology 2014;69: 200-208.

2.     Van der Woude HJ, Hazelbag HM, Bloem JL, Taminiau AH, Hogendoorn PC. MRI of adamantinoma of long bones in correlation with histopathology. AJR 2004;183:1737-1744.