Patients ages 6 months-21 years with ATRT, other INI1- or SMARCA4-deficient primary CNS malignant tumors, malignant rhabdoid tumor, rhabdoid tumor of the kidney, epitheloid sarcoma, chordoma, other INI1-negative or SMARCA4-deficient malignant tumors. Here, SMARCA4 is linked to chordoma.