Neurocytoma/lipoma (neurolipocytoma) of the cerebellum.

We describe a unique tumour that was removed from the posterior fossa of a woman aged 50 years. It was characterized histologically by bland, oval cells with fibrillary cytoplasm and by small groups of lipocytes. Immunocytochemical studies demonstrated expression of synaptophysin, neuron specific enolase and PGP 9.5, but a few cells also expressed glial fibrillary acidic protein and desmin. The combination of neuroectodermal and mesodermal features in this tumour is discussed in relation to primitive neuroectodermal tumours and neurocytoma.