Osteosarcoma in Paget Disease of Bone

Comments:
Fibroblastic Osteosarcoma arising in the setting of Paget disease of bone (PDB): Higher magnification of the previous image showing pagetic bone on the left and highly atypical spindle cell proliferation with osteoid production on the right.

Treatment & Prognosis: Paget sarcomas are high-grade tumors occurring in older patients that generally don't respond well to chemotherapy. Their prognosis is worse than conventional osteosarcomas. About 30% of patients have metastasis at presentation. The 2-year survival rate is 25% and 5-year survival is about 8%.