An 18-year-old male presents with a distal femur lesion showing an aggressive periosteal reaction with 'sunray spicules' on X-ray, soft tissue extension, and serum alkaline phosphatase of 450 IU/L. Staging workup reveals pulmonary nodules. The MOST appropriate initial treatment is:

• A Immediate wide local excision with endoprosthesis
• B Palliative radiotherapy to the primary lesion
• C Radical amputation above the knee
• D Neoadjuvant chemotherapy (MAP protocol) followed by limb salvage surgery ✓

Explanation

This is osteosarcoma (distal femur, adolescent, elevated ALP, sunray spiculation, soft tissue extension, pulmonary metastases). The current standard of care per COG/ESMO guidelines is neoadjuvant (pre-operative) chemotherapy using the MAP protocol (Methotrexate, Adriamycin/doxorubicin, Cisplatin) for 8–10 weeks, followed by definitive surgery (limb salvage or amputation), followed by adjuvant chemotherapy. Neoadjuvant therapy allows assessment of histological response (>90% necrosis = good prognosis) and reduces tumor size for limb salvage. Immediate surgery without chemotherapy worsens outcomes. Even with metastases, multimodal therapy including resection of metastases is attempted.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

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Written and medically reviewed by the StethoPrep medical team.