OSTEOFIBROUS DYSPLASIA LIKE-ADAMANTINOMA Figure 10-11 OSTEOFIBROUS DYSPLASIA LIKE-ADAMANTINOMA Left: Based on current criteria, the distinction of osteofibrous dysplasia from osteofibrous dysplasia-like adamantinoma is the presence of epithelial nests (clusters of three or more cells). Right: Wh... More

CLASSIC ADAMANTINOMA Figure 10-22 CLASSIC ADAMANTINOMA In addition to keratin AE1/AE3, the epithelial cells in adamantinoma are positive for p63 (left) and TLE1 (right). More

CLASSIC ADAMANTINOMA Figure 10-21 CLASSIC ADAMANTINOMA A,B: Typical biphasic appearance, with tubular differentiation in the epithelial component. C,D: The epithelial component in adamantinoma is positive for cytokeratin 14 (C) and p63 (D). More

OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA Figure 10-10 OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA Left: Osteoclast-like giant cells in osteofibrous dysplasia-like adamantinoma are close to the woven bone trabeculae. Right: High-power view shows small nests of epithelial cells. More

OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA Figure 10-7 OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA A: Lateral radiograph of the leg in a patient with osteofibrous dysplasia-like adamantinoma shows a lytic lesion in the anterior tibia, which involves the anterior cortex with extension into the medullar... More

CLASSIC ADAMANTINOMA Figure 10-16 CLASSIC ADAMANTINOMA Large epithelial islands are obvious at low-power magnification. More

OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA Figure 10-8 OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA The cortex and medullary cavity are involved by tumor. More

CLASSIC ADAMANTINOMA Figure 10-17 CLASSIC ADAMANTINOMA Epithelial elements have a tubular appearance (left), and epithelial cells can form interconnecting tubular structures (right). More

CLASSIC ADAMANTINOMA Figure 10-20 CLASSIC ADAMANTINOMA Left: There is a basaloid pattern with nuclear palisading, combined with squamous differentiation. Right: Though rare, squamous differentiation can be prominent. More

DEDIFFERENTIATED ADAMANTINOMA Figure 10-24 DEDIFFERENTIATED ADAMANTINOMA Left: Osteoid deposition and clear cell change can be seen. Right: Expression of keratin AE1/AE3 is largely retained in these areas. More

CLASSIC ADAMANTINOMA Figure 10-14 CLASSIC ADAMANTINOMA Left: Frontal radiograph of the leg demon strates a cortically based lytic and sclerotic lesion in the distal tibial diaphysis. Right: Resection shows a tan, fleshy intramedullary tumor scalloping the cortices. More

CLASSIC ADAMANTINOMA Figure 10-15 CLASSIC ADAMANTINOMA Left: The epithelial component is easily recognized and has a basaloid appearance, with some spindle cell changes. Right: Keratin AE1/AE3 staining highlights epithelial islands of variable size and shape. More

CLASSIC ADAMANTINOMA Figure 10-12 CLASSIC ADAMANTINOMA Left: Frontal radiograph shows a lobulated lytic lesion in the anterior cortex of the tibial diaphysis. Cortical destruction is present (arrow). Above: Axial CT of the lobulated lytic lesion with areas of cortical destruction (arrows). More

DEDIFFERENTIATED ADAMANTINOMA Figure 10-23 DEDIFFERENTIATED ADAMANTINOMA Left: The original characteristic epithelial differentiation is lost, and instead, areas of large pleomorphic epithelioid cells are seen, with a high mitotic rate. Right: Expression of keratin AE1/AE3 is retained in these l... More

CLASSIC ADAMANTINOMA Figure 10-19 CLASSIC ADAMANTINOMA Left: The spindle cells have a herringbone pattern. If the spindle cells predominate, especially in a biopsy specimen, the differential diagnosis is broad and includes synovial sarcoma. Right: Transitional areas are seen toward areas in whic... More

CLASSIC ADAMANTINOMA Figure 10-18 CLASSIC ADAMANTINOMA Different patterns may be seen within one tumor. In this lesion, a tubular and spindle cell pattern coexist. A: A transition pattern can be seen. B: The spindle cell component is highly cellular and monomorphic, morphologically resembling s... More

OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA Figure 10-9 OSTEOFIBROUS DYSPLASIA-LIKE ADAMANTINOMA Left: At low power morphology is very similar to that of osteofibrous dysplasia, with irregular woven bone lined by well-defined osteoblasts in a background of fibrous stroma. Distinction should be made ... More

CLASSIC ADAMANTINOMA WITH AGGRESSIVE FEATURES Figure 10-13 CLASSIC ADAMANTINOMA WITH AGGRESSIVE FEATURES Left: Frontal radiograph of the leg shows a large lytic lesion with cortical and medullary involvement. Cortical destruction is present. Right: The corresponding gross specimen in which the p... More

TIBIAL BONE TUMORS Figure 3-9 TIBIAL BONE TUMORS Adamantinoma (left) and osteofibrous dysplasia (right) (arrows). More