<aside> 📋
Adamantinoma is a rare, low-grade malignant bone tumor of epithelial origin, most commonly affecting the tibia.
</aside>
| Parameter | Description |
|---|---|
| Age group | 10–50 years (peak: 2nd–4th decades) |
| Sex | Slight male predominance |
| Location | 85% in tibial diaphysis, also fibula, humerus, radius, ulna |
| Incidence | Extremely rare (<1% of primary bone tumors) |
<aside> 📋
From a radiological standpoint, adamantinoma should be suspected in young adults presenting with an expansile, multilocular, lytic lesion in the anterior tibial cortex, especially if there’s a slow progression and lack of periosteal reaction.
</aside>
| Modality | Imaging features |
|---|---|
| XR | • Eccentric, expansile, multilocular, lytic lesion |
| • Predilection for anterior tibial cortex | |
| • May have cortical breach or soft tissue extension | |
| • Well-defined margins, with or without sclerosis | |
| CT | • Better delineates cortical destruction, multilocularity |
| • May show matrix calcifications (though usually absent) | |
| MR | • T1: Intermediate to low signal |
| • T2: Heterogeneous high signal with cystic/hemorrhagic areas | |
| • Post-contrast: Variable enhancement | |
| • Helpful in assessing medullary extension and soft tissue involvement |
(A) Frontal radiograph of the left tibia and fibula: an expansile osteolytic lesion with incomplete sclerotic rim and thinning of adjacent cortex, as well as pathological fracture (arrow) in the upper segment of left tibia. Soft tissue window (B), bone window (C), MPR (D) and 3D reconstruction (E) of the left tibia and fibula: an expansive bone destruction accompanied with pathological fracture (arrow) was detected in the upper segment of the left tibia. The CT attenuation was about 52 HU. Incomplete sclerotic rim, and multiple cystic and honeycomb-like changes were found on multiplanar reformation images. The medial cortex showed ridge-like changes (triangle). Axial (F) T1-weighted, axial (G) and coronal (H) T2FS-weighted MR images of the left tibia and fibula: a low T1, high T2 signal marrow infiltrating neoplasm involving the upper tibial shaft accompanied by edema (arrow) of surrounding soft tissue. (I, J) Histological specimen: there were many glandular tubular structures (arrow) among fibrous tissues under the microscope. (K) Radiograph for postoperative review.
Chen J, Zhang J. Adamantinoma filling the medullary space of the tibia: A case report. Radiology Case Reports. 2019;14(11):1330-1333. doi:https://doi.org/10.1016/j.radcr.2019.08.013
| Diagnosis | Key Features |
|---|---|
| ‣ | Benign, diaphyseal lesion in children, lacks epithelial cells |
| ‣ | No epithelial cells, usually metaphyseal, not cortical |
| ‣ | Malignant, aggressive periosteal reaction, soft tissue mass |
| ‣ | Diaphyseal or metaphyseal lesions, typically in younger children |