[An exceptional variety of medulloblastoma: melanotic medulloblastoma]

We report a new case of melanotic medulloblastoma of the vermis in a 3 1/2 year old boy. This tumor showed a typical histological appearance with pseudoepithelial pigmented structures immunoreactive for S100 protein and vimentin. The tumor did not recur after total surgical removal and post operative radiation. However, after a 10 year follow-up, imaging demonstrated that a second tumor occurred in the left cerebellar hemisphere, which, on histological examination, was a typical glioblastoma. Hypothesis concerning the histogenesis of the second tumor, as well as a causal association with radiation therapy and possible contribution of growth hormone therapy are discussed.