Frozen shoulder or something else?

Case ID Number: 
20110223FZ
Image Modality: 
path image
Benign/Malignant: 
Malignant
Body Region: 
shoulder, humerus, upper arm
Bone Name: 
scapula
Periosteal Reaction: 
absent
Tumor Behavior: 
aggressive
Tumor Density: 
lytic