Anaplastic medulloblastoma with granular cell change.

Granular cell change secondary to lysosomal accumulation has been described in a variety of tumors of the nervous system of presumed glial or schwannian derivation. Herein we report the case of a 15-year-old female with an anaplastic medulloblastoma which histologically demonstrated areas with granular cell change. These granular cells co-expressed neuronal immunohistochemical markers, including synaptophysin, chromogranin, and Neu-N, and demonstrated accumulation of lysosomes and dense core granules in the same cells at the ultrastructural level. This unusual finding suggests that the spectrum of granular cell change should be expanded to include tumors with primarily neuronal differentiation.