Age / Sex : 20 / M

Classic adamantinoma

Discussion

Findings:

Eccentric geographic, cortically located lobulated lesion in the tibia anterior cortex diaphysis

with thickened anterior cortical bone

and focal cortical breakthrough and medullary extension

Mass shows T2 heterogeneous high signal intensity with contrast enhancement

Differential Diagnosis:

osteofibrous dysplasia, osteofibrous dysplasia-like adamantinoma, adamantinoma

Diagnosis:  

Classic adamantinoma

Discussion:

1. A rare malignant tumor, almost exclusively seen in the diaphysis of the tibia


2. Slow progression, with potential to metastasize


3. Radiographic findings

- cortically based lesion (usually anterior tibia), eccentric & expansile

- extends along length of bone and may extend into the marrow cavity

- “Soap-bubble” appearance

- presence of satellite lesions

- MRI:  assessment of the extent and invasiveness of the lesion

4. Differential diagnosis

- OFD, OFD like adamantinoma

- adamantinoma : larger size, higher incidence of medullary cavity involvement, ill-defined margin, extraosseous spread
 

References:

1. Clinical Radiology 2014;69:200-208


2. AJR 2004;183:1737-1744