[The neuroblastoma of the cerebellum].

A report is given demonstrating the maturation of a neuroblastoma of the cerebellum and its transformation into a ganglioglioma. In a male infant statomotor retardation was diagnosed at the age of 6 months. 9 months later, he developed symptoms indicating a cerebellar neoplasm. Craniotomy showed a vermian tumor which was classified histologically as a neuroblastoma. 51/2 years after the first operation, a control CT scan revealed a recurrence which showed light and electron microscopically the structure of a ganglioglioma. The child is now 8 years old and develops relatively well. On the basis of this observation and of the limited data published in the literature, it is suggested that, with the aid of light microscopy, it is possible to distinguish neuroblastomas from common medulloblastomas what is of practical importance because neuroblastomas seem to have a better prognosis. However, differential diagnostic criteria need further precision. Problems of the nosological placement of neuroblastomas and their histogenetic relationship to medulloblastomas are discussed. The statement of the WHO Classification of Tumors of the CNS that neuroblastomas correspond to grade IV cannot be accepted generally.