Limb-Salvage Surgery for Pediatric Osteosarcoma

This study was approved by the Ethics Committee of Affiliated Tumor Hospital of Xinjiang Medical University and informed consent was obtained from all patients. Inclusion criteria: primary malignant tumor of bone near the knee joint; neoadjuvant chemotherapy is effective; the tumor did not invade the epiphyseal plate; the tumor did not invade important blood vessels and nerves; no infection. Exclusion criteria: pathological fracture; no limb preservation conditions; tumor invading epiphysis. There were 3 male and 2 female patients, the age range was from 8 to 14 years, with an average of 11.6 years. Distal femoral lesions were observed in 2 cases and proximal tibial lesions in 3 cases. All patients underwent X-ray, computed tomography, magnetic resonance imaging, and emission computed tomography examination, and a biopsy was performed after the examination. All cases were common osteosarcomas with no distant metastasis. According to the Enneking staging system, all cases were classified as stage IIB. The distance between the epiphyseal plate and the tumor was >1 cm in all cases. The magnetic resonance imaging image San Julian classification^{[5 (link)]} was applied to classify the lesions. Type I lesions are defined as a distance from the edge of the tumor to the epiphyseal plate >2 cm; for Type II the distance from the edge of the tumor to the epiphyseal plate <2 cm or adjacent; for Type III the epiphyseal plate is partially in contact with the tumor or invaded epiphysis. All cases were classified as San Julian I or San Julian II and the epiphysis could be preserved. All the patients were treated with preoperative neoadjuvant chemotherapy, surgery, and postoperative adjuvant chemotherapy. All lesions were sensitive to preoperative neoadjuvant chemotherapy, and no pathological fractures occurred during chemotherapy. The chemotherapy regimen consisted of cisplatin 100 mg/m², adriamycin 80 mg/m², methotrexate 12 g/m², and ifosfamide 12 g/m².