To assess survival outcome of pediatric patients with localized osteosarcoma of the extremities in Upper Egypt, identify factors of prognostic significance for survival, and to determine factors predictive of surgical methods employed in these patients, and developing a clinical model for risk prediction.

Background Osteosarcoma is the most common of all primary malignant bone tumors. Accounting for about 2.6% of all pediatric neoplasms, it predominantly occurs in the extremities, with a peak incidence in the second decade of life.

In Upper Egypt, we have a higher proportion of the population in underdeveloped communities with limited access to medical care so the patients usually seek medical advice at advanced stage leading to a higher prevalence of metastatic disease at initial presentation, as well as a greater proportion of larger tumor size that more likely to be associated with potential adverse risk criteria prior to surgery.

A previous study from Upper Egypt showed that a metastatic disease at diagnosis was independently correlated to a dismal outcome. Since the effect of many other factors of prognostic significance, such as, gender, age, tumor location and response to chemotherapy may have been mitigated by the large effect of the metastatic disease on the prognosis; So, here, we will analyze the data of 30 patients with non-metastatic osteosarcoma of the extremities, to determine prognostic factors associated with survival, and also to develop a model for a better prediction of factors correlated to that a certain surgical approach was employed in these patients based on their baseline clinical data and the tumor response to chemotherapy.

Patients & Methods We will carry out a retrospective analysis of data assembled from medical records of 30 pediatric patients with a histologically-verified non-metastatic osteosarcoma of the extremities treated at South Egypt Cancer Institute with a unified chemotherapy protocol between January 2001 and December 2015. These data will be categorized according to demographic data, clinical characteristics, tumor response to chemotherapy, and surgical methods employed in these patients. Prognostic factors will be determined using univariable and multivariable methods. A predictive model for surgical outcomes in these patients based on the baseline clinical factors, and their tumor response to chemotherapy will be developed.

Inclusion Criteria:

• Patients whose age less than 19 years.
• Patients diagnosed with verified osteosarcoma involving the extremities.

Exclusion Criteria:

• Patients whose age more than 19 years.
• Non-extremities Osteosarcoma .

30 pediatric patients with a histologically-verified non-metastatic osteosarcoma of the extremities treated at South Egypt Cancer Institute with a unified chemotherapy protocol between January 2001 and December 2015.