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What is Sun-ray appearance is characteristic of and explain in detail?
Osteosarcoma is the second most common, and a highly malignant primary bone tumour. Sun-ray appearance: In X-ray, as the periosteum is unable to contain the tumour, the tumour grows into the overlying soft tissues. New bone is laid down along the blood vessels within the tumour growing centrifugally, giving rise to a 'sun-ray appearance' on the X-ray. Reference: Maheshwari; Essential Ohopaedics; 9th ed Page no: 240