Secondary osteosarcoma in Paget disease

: The incidence of Paget's disease in Germany is about 3%. Up to 10% of all affected individuals develop secondary osteosarcomas in the affected bone areas. Compared to primary osteosarcoma patients with Paget's sarcoma differ in regard to age, tumor localisation, therapy, prognosis and radiological symptoms. The following case report describes clinical features, therapy and the typical radiological findings.