Presentation
Patient with history of trauma. X-rays of the knee showed a lesion in the distal femur.
Patient Data
Multilobular juxtacortical well-defined lytic lesion in distal metaphysis/diaphysis of left femur. It measures 47 x 34 x 18 mm and has a surrounding sclerotic rim. The soft tissues are preserved. Findings are compatible with non-ossifying fibroma.
Pathology Report
Macroscopic findings:
- Bone tumor of distal femur was received, multiple fragments of bone tissue in 6 milliliter volume. Representative sample was included
Microscopic findings:
- Non-ossifying fibroma
Case Discussion
Some authors believe that the radiological characteristics of non-ossifying fibroma are pathognomonic and diagnosis does not require any histopathological proof. However, in this case, despite the CT findings, the surgeons decided to pursue invasive biopsy which confirmed a non-ossifying fibroma.