A 15-year-old boy feels pain in the region of the left knee joint. Objectively: the soft tissues in the affected region are infiltrated, the joint function is limited. Radiography reveals a focus of bone destruction in the distal metaepiphysial segment of the left femur. The destruction is accompanied by periosteal detachment and a defect formed within cortex of Codman triangle bone. X-ray of chest shows multiple microfocal metastases. What is the most likely pathology?