Establishment of a Risk Factor and Clinical Prediction Model for Distal Metastasis and Prognosis of Ewing Sarcoma: A SEER-Based Study

Abstract Background: the purpose of this study was to establish and validate a clinical predictive model for predicting the risk of metastasis and survival of patients with Ewing sarcoma. Methods: the data of patients diagnosed with Ewing' sarcoma (ES) from 2004 to 2015 were collected from the Surveillance, Epidemiology and final results Database (The Surveillance, Epidemiology, and End Results, SEER). By excluding vacancy data and random number method, the screened data were divided into training set (nasty 2520) and verification set (nasty 1076). Logistic regression analysis was used to analyze the risk factors related to tumor metastasis, and Kaplan-Meier curve and Cox proportional hazard model were used to explore the related risk factors affecting patient survival. A visual line chart (Nomogram) based on the above analysis was developed to predict ES tumor metastasis and patient's 3-and 5-year survival probability, and to verify it. Results: in the analysis of tumor metastasis, it was found that age over 60 years old, operation, tumor volume, radiotherapy and chemotherapy were the high risk factors of tumor metastasis. The establishment of Nomogram, to predict the risk of tumor metastasis and the use of ROC curve showed that the predictive model had better predictive ability (AUC=0.744,95%CI0.721-0.768), which could predict the existence of tumor metastasis. In the survival analysis of the training set, age (20-29, 30-60, > 60), location of tumor (axial, bone, facial bone), mode of operation (local excision, radical resection), number of primary tumor (multiple), tumor stage M (M 1,), Stage Group (II,III,IV,UNK stage), tumor volume (5 cm 10 cm, greater than 10cm), spread range (local metastasis). Distal metastasis), radiotherapy and chemotherapy are independent prognostic factors of patients. The Nomogram, established to predict 3 years and 5 years of patients is verified by the verification set, which shows a good consistency (c index = 0.747, 95% CI, 0.696-0.797).Conclusion: Nomogram with good predictive ability is developed to predict the risk of tumor metastasis and the 3-and 5-year survival rate of patients with ES. External data validation is still needed in future clinical applications, especially outside the United States.