Which of the following is true about medulloblastoma?

The tumor occurs predominantly in children and exclusively in cerebellum (infratentorial tumor). Histopathological hallmark is Homer-Wright rosettes. Mitoses are abundant, and markers of cellular proliferation, such as Ki-67, are positive in a high percentage of the cells. Dissemination of tumor occurs through CSF giving rise to either extensive growth along the surface likened to "icing," or nodular "drop metastases," which tend to involve the cauda equina. It is a radiosensitive tumor. Radiotherapy improves the survival in children. Cranio-spinal irradiation (CSI) reduces the recurrence from CSF dissemination.