At the time of diagnosis of a high-grade osteosarcoma of the distal femur, which investigation is essential to stage the most common site of metastatic disease?

• A Technetium-99m bone scan of the axial skeleton
• B Magnetic resonance imaging of the brain
• C Positron emission tomography of the abdomen
• D Computed tomography of the chest ✓

Explanation

The lung is the most common site of metastasis in osteosarcoma, so contrast-enhanced CT of the chest is part of standard baseline staging and guides both prognosis and the plan for resection of pulmonary nodules. Bone scan detects skeletal skip lesions and other bony metastases but does not image the dominant metastatic site. Abdominal PET and brain MRI are not routine for classical osteosarcoma staging.

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.