Recently, studies have demonstrated the expression of LGR5 in several tumors including colorectal, gastric carcinoma, esophageal adenocarcinoma (8,9,15), liver (16), ovarian carcinoma (12) and Ewing sarcoma (22) and have shown that the overexpression of LGR5 is associated with poor prognosis. This evidence concerns the gene LGR5 and Ewing sarcoma.