An immunohistological study of 15 chordomas, six chondrosarcomas, four liposarcomas and seven carcinomas on paraffin embedded samples using anti-cytokeratin, anti-epithelial membrane antigen (EMA), anti-S100 protein, anti-vimentin and anti-neurofilaments showed that chordomas has a characteristic immuno-staining, i.e. positive for cytokeratin, EMA, S100 protein and vimentin; and negative for neurofilaments. This immuno-staining allows a clear distinction of chordomas from other tumours.