A bone biopsy from a patient with Paget's disease is examined histologically. The characteristic finding is:
- A Sheets of plasma cells with Russell bodies and monoclonal immunoglobulin
- B Non-caseating granulomas with multinucleated giant cells and epithelioid histiocytes
- C Mosaic pattern of lamellar bone with irregular jigsaw-puzzle cement lines and disorganized collagen ✓
- D Excessive unmineralized osteoid with widened seams and absent tetracycline uptake
Correct answer: C. Mosaic pattern of lamellar bone with irregular jigsaw-puzzle cement lines and disorganized collagen
Explanation
Paget's disease shows a characteristic mosaic (jigsaw puzzle) pattern of lamellar bone with irregular cement lines reflecting chaotic bone remodeling. The collagen fibers are disorganized rather than the normal parallel arrangement. Option A describes multiple myeloma. Option B describes sarcoidosis or tuberculosis. Option D describes osteomalacia.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.