Monitoring And Evaluation The Effect Of Neoadjuvant Chemotherapy Of Patients With Osteosarcoma

Background: Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. Years ago, all patients with osteosarcoma were treated by amputation but the cure rate was under 10% and almost all patients died within a year from diagnosis. Today, for localized osteosarcoma at onset treated in specialized bone tumour centres with pre- and postoperative chemotherapy associated with surgery, the percentage of patients cured varies between 60% and 70%. Surgery is conservative (limb salvage) in more than 90% of patients. Prognosis is more severe (cure rate about 30%) for tumours located in the axial skeleton and in patients with metastasis at onset and in patients with recurrent disease. Presurgical chemotherapy has been advocated for these patients because of putative improvement in event free survival (EFS). The advantages of systemic chemotherapy include early administration of systemic chemotherapy, shrinkage of primary tumor, and pathologic identification of risk groups. The theoretic disadvantage is that it exposes a large tumor burden to marginally effective chemotherapy. Thus, how to distinguish poor responders from good responders before the end of chemotherapy is very important. This research contribute to monitoring and evaluation the effect of chemotherapy in patients with osteosarcoma.Objective:To determine the prognostic factors that influence survival of patients with nonmetastatic, high-grade, osteosarcoma of the extremities in China. Materials and Methods:A homogeneous group of 72 patients treated at Peking University People's Hospital Muscularskeletal tumor center between June 2003 and June 2007, were retrospectively evaluated in relation to gender, age, height, tumor site and size, blood type, serum levels of alkaline phosphatase, X-ray and MRI changes, histological response to preoperative treatment.Results:Upon Univariate analysis, tumor necrosis was significantly related to gender, tumor volume change, tumor margin and T2 signal intensity of the extraosseous component of bone sarcomas. Multivariate analysis, tumor necrosis was only related to tumor volume change. Upon multivariate analysis, good histological response to treatment maintained independent prognostic values on the outcome of patients with nonmetastatic osteosarcoma of the extremities.Conclusion:Event free survival (EFS) was related to the tumor necrosis, the level of alkaline phosphatase (AKP) and the change of T2 signal of the extraosseous component. Tumor necrosis was related to the volume change after preoperative chemotherapy. These factors must be considered when deciding risk-adapted treatments for osteosarcoma patients.