A 65-year-old male with Paget's disease of bone develops bone pain, deformity, and elevated alkaline phosphatase (ALP). The most feared malignant complication of Paget's disease is:
- A Osteosarcoma arising in pagetic bone (Pagetic osteosarcoma) ✓
- B Chondrosarcoma transformation of pagetic cartilage
- C Multiple myeloma developing from pagetic bone marrow
- D Fibrosarcoma of the periosteum
Explanation
Paget's disease is complicated by malignant transformation to osteosarcoma in approximately 1% of cases, which carries an extremely poor prognosis (median survival <12 months despite treatment). Pagetic osteosarcoma arises most commonly in the femur, humerus, and skull. It presents with sudden increase in pain and rapidly rising ALP and LDH. Histologically it is similar to conventional osteosarcoma but tends to be more pleomorphic. While chondrosarcoma and fibrosarcoma can occasionally occur in Paget's disease, osteosarcoma is by far the most frequent and the most clinically tested complication. Bisphosphonate therapy for Paget's does not clearly prevent sarcomatous transformation.
Reference: Maheshwari Essential Orthopaedics, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.