Juvenile pilocytic astrocytoma 'pilomyxoid variant' with spinal metastases.

We report a case of juvenile pilocytic astrocytoma of the hypothalamic/chiasmatic region with cerebrospinal fluid dissemination in a 16-month old girl. The tumour in this case had unusual histological features including the abundance of myxoid background, the absence of Rosenthal fibres and the presence of an angiocentric pattern. These features are consistent with the recently described "variant" named pilomyxoid astrocytoma. It remains unclear whether pilomyxoid astrocytoma represents an aggressive variant of classical juvenile pilocytic astrocytoma, or an entirely distinct clinico-pathological entity. Larger series and new molecular techniques may answer this question in the future.