Introduction
- Occurs in a small percentage of patients with Paget’s disease
- Age range of patients is 46-91 years
- M:F = 2:1.
- High-grade osteosarcoma most common malignancy arising in Pagetoid bone
- Chondrosarcoma, fibrosarcoma, and MFH may also occur
- Patients will have elevated serum alkaline phosphatase; sudden jump in usual level observed should raise suspicion of malignant change
Plain films
Site
Sites most commonly involved are pelvis, humerus, and femur
h5 Tumor effect on bone
Frank bone destruction common
Tumor response to bone
- Often little reaction to tumor
- Margins ill defined
- Periosteal new bone formation is rare
Soft tissue mass
May develop
Complications
High incidence of pathologic fracture
Clinical outcome
Prognosis worse than in conventional osteosarcoma
- Generally large size and axial location of tumors
- Occurrence in older patients usually precludes aggressive chemotherapy