This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Unknown
Premalignant bone lesion among the following is - 
Select and explain. 
A. Pagets disease, B. Osteoid osteoma, C. Osteochondroma, D. Enchondroma
A: Pagets disease
Answer: A: Pagets disease 
Explanation: Ans. is 'a' i.e., Pagets disease Paget's disease o Paget s disease is characterized by increased bone turnover and enlargement and thickening of the bone the internal architecture is abnormal and the bone is usually brittle, o Primary defect is in osteolastic. o It is marked by regions of furious osteolastic bone resorption which is followed by a period of hectis bone formation. The net effect is gain in bone mass. o It has the following three stages Initial osteocytic stage Mixed osteoclast osteoblastic stage Burned out quiescent osteosclerotic stage o Following complications can occur in Paget's Increased risk of development of sarcomas (osteosarcoma chondrosarcoma) Fractures in weight bearing bones Osteoarthritis High output cardiac failure Cranial nerve compression Otoscleosis