Where is the lesion?
Left iliac bone
What are the radiological characteristics/findings?
Large lytic lesion with wide zone of transition, cortical destruction, and large soft tissue component.
No specific matrix.
What is the differential diagnosis of an aggressive iliac bone lesion?
* Metastasis
* Plasmacytoma: solitary plasma cell tumor expansile lytic lesion with bone destruction and soft tissue component. Usually shows low signal intensity on T2 with variable post contrast enhancement.
* Chondrosarcoma: malignant cartilage tumor destructive lytic lesion with intralesional rings and arcs calcification (chondroid matrix). High signal intensity on T2.
What is the most likely diagnosis?
Plasmacytoma
There is lytic expansile bony lesion in the left iliac bone. There is cortical break with large soft tissue component. Bulk of soft tissue mass in left gluteal region. Another smaller lytic lesion in left iliac bone noted. Features are likely suggestive of metastatic disease.