Age / Sex : 28 / F

Chief complaint: shoulder pain
              ESRD patient (underwent hemodialys for 3 years) 
                         

Brown tumor with secondary aneurysmal bone cyst

Discussion

Findings:

Plain film 

Geographic osteolytic bone tumor without sclerotic rim

Destructed cortical margin on medial side

relatively sharp margin, no prominent periosteal reaction

MR

   Multiloculated cystic bone tumor with enhanced wall

   Fluid-fluid level

   Destructed cortical margin

Differential Diagnosis:

1. brown tumor with aneurysmal bone cystic change
2. Giant cell tumor with aneurysmal bone cystic change

3. Telangiectatic osteosarcoma.

Diagnosis:  brown tumor with ABC change

Discussion:

Skeletal brown tumors in CRF patients: 1.5-13%

More common in young female with longevity of HD

Often in pelvis, ribs, clavicle, mandible, extremities

Usually soft, painless, minimally tender (if without fracture)

Not a true neoplasm, reactive lytic bone lesion in untreated primary or secondary hyperparathyroidism

Increased osteoclastic activity -> osteopenia,subperiosteal bone resorption -> reactive osteoblastic activity -> ingrowth of fibrovascular tissue

Histology : multinuclear osteoclasts, mononuclear cells, fibroblasts, hemosiderin

Difficult to DDx. with other giant-cell lesions

Clinical diagnosis is based on the association with hormone therapy

Imaging findings

Well-defined purely lytic lesions, little reactive bone formation

Cortex may be thinned, expanded (not often penetrated)

Solid components; intermediate-low SI on T1- and T2WI

Foci of increased SI with cystic and hemorrhage, may have fluid-fluid levels

References:

1. RadioGraphics 2013; 33: 197-211.

2. RadioGraphics 2009; 29: 380-383.

3. RadioGraphics 1993; 13: 357-379.

4. Skeletal Radiol 2011;40: 205–213.