Bone Tumors — MCQs

A 16-year-old boy presents with a 3-month history of progressively worsening pain and swelling around the distal right femur. Plain radiograph shows a permeative lytic lesion with Codman's triangle and a sunburst periosteal reaction. A core needle biopsy is performed and the histopathological specimen is shown in Image 1. Following staging workup, imaging confirms the lesion is confined to the bone with no skip lesions and no distant metastases. What is the most appropriate next step in management?