Tumours in Iceland. 15. Ependymoma. A clinicopathological and immunohistological study

Thirteen ependymomas reported to the Icelandic Cancer Registry during a 32-year period (1955-1986) were histologically reviewed and reclassified according to the WHO Histological Typing of Tumours of the Central Nervous System. The annual incidence rate of ependymoma was 0.20/100.000. Clinical observations and data on biological behaviour and immunohistochemistry are presented. Four tumours were supratentorial, six infratentorial and three intraspinal. There were ten males and three females with a mean age of 32 years (range 2.5-68). The mean postoperative survival of nine surgically treated patients was 35.5 months. Histologically, eight tumours were classical ependymomas, three anaplastic and two myxopapillary. Of 11 tumours stained for GFAP, nine were positive. Nine of 10 tumours tested were positive for vimentin, five for NSE and four for S-100. None of the 10 tumours showed reactivity with AFP, CEA, chromogranin, desmin, factor VIII, keratin or neurofilament.