Renal Ewing sarcoma treated with apatinib.

Renal Ewing sarcoma (RES) is an extremely rare disease. The standard treatment for this disease is lacking, and clinical experience needs to be accumulated. Here, we report a case of RES that rapidly developed to metastatic disease and was refractory to radiotherapy and chemotherapy; however, the case obtained a partial response based on Choi criteria by orally taking antiangiogenic drug apatinib. Our case suggests that apatinib may be a therapeutic option for RES.