What radiographic sign is most closely associated with osteosarcoma?

• A. Onion skinning
• B. Codman's triangle
• C. Sunburst pattern
• D. Sclerotic borders

Answer: (B)

The sign most closely associated with osteosarcoma is Codman's triangle. This radiographic finding occurs when a tumor lifts the periosteum away from the bone, leading to the formation of a triangular area of new bone at the edge of the lesion. This is a characteristic response to aggressive bone lesions, particularly malignant ones like osteosarcoma.

Codman's triangle indicates periosteal reaction that is often seen in high-grade tumors, demonstrating the aggressive nature of osteosarcoma as it invades surrounding tissues. This sign, combined with other imaging features, can help differentiate osteosarcoma from other types of bone lesions.

In contrast, onion skinning is more commonly associated with conditions such as Ewing's sarcoma, representing a different type of periosteal reaction. The sunburst pattern may appear in osteosarcoma and shows aggressive periosteal behavior but is not as specific as Codman's triangle for this condition. Sclerotic borders are typically seen in benign lesions and do not align with the characteristics of osteosarcoma, which usually presents with more aggressive and less defined borders.