A , Schematic representation of the family tree of index case. Karyotype and SMARCB1/INI1 molecular evaluation (E) is reported (wt= wild type; Arg40X denotes the constitutional mutation found in index case). Present age and age of onset of clinical symptoms is given in years (y). B, Brain MRI of primary ATRT lesion. C, MRI of metastatic lesion. D, Hematoxylin eosin staining and E, SMARCB1/INI1 staining of ATRT tumor from index case, showing absence of SMARCB1/INI1 protein expression in cancer cells.