The most important prognostic factor for survival in osteosarcoma following neoadjuvant chemotherapy and limb salvage surgery is:

• A Preoperative tumor size
• B Histological response to chemotherapy (percentage tumor necrosis) ✓
• C Surgical margin width
• D Patient age at diagnosis

Explanation

The histological response to neoadjuvant chemotherapy, measured as percentage tumor necrosis in the resected specimen, is the strongest prognostic factor in osteosarcoma. A good response (≥90% necrosis, Huvos Grade III/IV) correlates with significantly improved overall survival (~70–80%) compared to poor responders (<90%). Rosen's classification and Huvos grading both use necrosis to guide post-operative chemotherapy selection. Margin and size are important but secondary to necrosis response.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.