One Ewing's sarcoma and one neuroblastoma taken at relapse expressed FGFR3IIIS but not FGFR3IIIc; FGFR3IIIS and FGFR3IIIc were not detected in a neuroblastoma taken post-treatment (although the RNA was successfully amplified for β2-microglobulin). This evidence concerns the gene HLA-G and Ewing sarcoma.