Medulloblastoma with Extensive Nodularity
The nodules are composed of a uniform population of tumor cells. The background is reticulin-free and is rich in neuropil-like tissue. Mitotic activity is not significantly increased. The cells often show streaming in parallel rows. Following chemotherapy and/or radiation therapy, this tumor may undergo further differentiation and become dominated by a population of ganglion cells. Like desmoplastic medulloblastoma, this variant also has favorable outcome as compared to the classic medulloblastoma.