In contrast, high nuclear Survivin expression has been shown to be an independent indicator of a favourable prognosis in osteosarcoma, breast cancer, and gastric carcinomas (Okada et al, 2001; Kennedy et al, 2003; Trieb et al, 2003) and, moreover, it has been associated with a less-progressive cytologic grade in pediatric ependymomas and choroid plexus tumours of the brain (Altura et al, 2003). This evidence concerns the gene BIRC5 and ependymoma.