BIRC5 and chondrosarcoma: The three most common survivin isoforms, wild type (wt) survivin, survivin 2b and survivin Δex3, were all expressed significantly higher in high-grade chondrosarcomas (grade II and III) compared with low-grade chondrosarcomas (P⩽0.001 for wt survivin, P⩽0.01 for survivin 2b and P⩽0.05 for survivin Δex3) (Figures 4a–c).