The efficacy and safety of apatinib in Ewing's sarcoma: a retrospective analysis in one institution.

backgroundEwing's sarcoma (ES) is a highly aggressive and metastatic neoplasm occurring mainly in children and young adults. The standard treatment of localized ES requires a combination of surgery, chemotherapy, and radiotherapy. Although the 5-year survival rate for local ES has improved, the survival rate and prognosis are still very poor for metastatic or recurrent ES patients. The aim of this study was to investigate the efficacy and safety of apatinib, a specific vascular endothelial growth factor receptor 2 inhibitor, in ES patients.

methodsThis retrospective analysis involved eleven patients with ES not amenable to curative treatment. All patients suffered poor responses to two cycles of chemotherapy (vincristine, doxorubicin, and cyclophosphamide). Apatinib 500 mg (or 250 mg) was given daily. Tumor responses were assessed according to the Response Evaluation Criteria in Solid Tumors 1.1. Survival analysis was performed by the Kaplan-Meier test. The safety profile was also recorded.

resultsThe mean age of the patients was 18 (range, 10-31) years. The 12-month overall survival and progression-free survival rates were 90% and 72%, respectively. Four patients achieved partial response, and four patients achieved stable disease, with objective response rate of 40%. The median follow-up in our study was 16 months (range, 3-26 months). The most common adverse events included hand-foot skin reaction (n=5; 45%), oral ulcers (n=4; 36%), and gastrointestinal discomfort (n=4; 36%).

conclusionApatinib may provide as second- or first-line treatment options for ES patients, particularly in chemoresistant cases. Further studies with more cases and longer follow-up will be necessary to determine the clinical efficacy and safety of apatinib in ES patients.