SMARCB1 and atypical teratoid rhabdoid tumor: MRTs of the brain, known as Atypical Teratoid Rhabdoid Tumor (ATRT), were initially considered as a medulloblastoma subgroup with poor prognosis and have been suggested as a separate entity since 1996 [7,8], but only recently systematic SMARCB1/INI1 immunohistochemistry and mutational screening in newly diagnosed pediatric brain tumors [9-11] has allowed the definition of the incidence, clinical, pathologic and molecular features of ATRT [11].