A 65-year-old man with Paget's disease presents with progressive bowing of the left femur and recent increase in pain. ALP is massively elevated (1800 U/L). X-ray shows coarsened trabeculae, cortical thickening, and advancing 'blade of grass' or 'flame-shaped' lytic front in the femoral shaft. The most feared complication of Paget's disease that requires urgent monitoring is:
- A High-output cardiac failure due to AV shunting in Pagetoid bone
- B Hypercalcemia of Paget's disease
- C Sarcomatous transformation (Paget's sarcoma — osteosarcoma) ✓
- D Hearing loss from skull base involvement
Explanation
Paget's sarcoma (malignant transformation to osteosarcoma or fibrosarcoma) occurs in approximately 1% of patients with Paget's disease, rising to ~5–10% in patients with polyostotic disease. It carries an extremely poor prognosis (5-year survival <5%). Clinical clues include rapidly increasing pain in a known Paget's lesion, new soft tissue mass, or sudden rise in ALP. Histologically it is most commonly osteosarcoma. High-output cardiac failure and hearing loss are recognized complications but not the 'most feared' compared to sarcomatous change. Hypercalcemia occurs only in immobilized patients with Paget's disease.
Reference: Maheshwari Essential Orthopaedics, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.