Medulloblastomas present generally a-specifically as a fast-evolving posterior fossa tumor. Medical literature is poor concerning clinical features of medulloblastomas and their potential significance. In the present study, we reviewed 91 pediatric observations of medulloblastomas treated in Lille between 1997 and 2017. Clinical and epidemiological variables were collected and intercorrelated. They were also compared with anatomical and pathological findings, and outcome, with the aim of defining clinical-pathological entities. We also compared the group with 32 cases of posterior fossa ependymoma and 130 cases of cerebellar astrocytoma treated during the same period. We found that in medulloblastomas, the M/F ratio was higher and diagnostic delay was shorter than in astrocytomas. Also, the mean age was older than in ependymomas. Intracranial hypertension was constant; we further observed that altered general status was common (16.5%) and correlated with a metastatic tumor. We delineated two clusters: the “nodular” cluster, which associates young age, cerebello-pontine angle tumor, herniation, desmoplastic tumor, and tumor predisposition syndrome; and the “metastatic” cluster, which associates altered status, initial metastases, hydrocephalus, and diagnostic delay. Meticulous collection of clinical data at the initial phase is integral part of the oncological evaluation, with a search for genetic and prognostic risk factors, which then permits us to define clinical-pathological entities.