We report here a 4-month-old child with a large, solid enhancing mass involving predominantly the suprasellar and diencephalic regions, with extension of both hemispheres. The patient underwent partial resection of the mass by right temporal craniotomy. Histological diagnosis was of a low-grade glioma consistent with pilomyxoid astrocytoma. Cytogenetic analyses revealed an insertion on chromosome 17 that involved disruption of the BCR gene. This finding suggests a possible rearrangement of this gene that could act in a similar way to chronic myeloid leukemia with formation of a chimeric tyrosine kinase protein. This study may suggest the use of inhibitors of tyrosine kinase proteins as an alternative treatment approach in cases of refractory or disseminated pilocytic astrocytomas.