Supratentorial recurrences in medulloblastoma.

Four children with medulloblastoma had massive supratentorial recurrences in the region of the cribriform plate after adequate craniospinal irradiation. The pathogenesis of these recurrences is probably related to underdosage to this region by shielding of the eyes. This hypothesis was corroborated by autopsy findings in two other patients in whom subfrontal implants were histologically different from recurrences elsewhere. Two possible solutions to avoid this problem in the future are suggested.